Citation
An environmental impact assessment of chemicals used in hydraulic fracturing operations for a selection of oil and gas wells compared to coal bed methane wells in Colorado

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Title:
An environmental impact assessment of chemicals used in hydraulic fracturing operations for a selection of oil and gas wells compared to coal bed methane wells in Colorado
Creator:
Zelinka, David Lawrence ( author )
Place of Publication:
Denver, Colo.
Publisher:
University of Colorado Denver
Publication Date:
Language:
English
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1 electronic file (82 pages) : ;

Thesis/Dissertation Information

Degree:
Master's ( Master of science)
Degree Grantor:
University of Colorado Denver
Degree Divisions:
Department of Civil Engineering, CU Denver
Degree Disciplines:
Civil engineering

Subjects

Subjects / Keywords:
Coalbed methane -- Environmental aspects ( lcsh )
Hydraulic fracturing -- Environmental aspects ( lcsh )
Genre:
bibliography ( marcgt )
theses ( marcgt )
non-fiction ( marcgt )

Notes

Review:
This study estimates the environmental impact of chemicals used for hydraulic-fracturing (HF) operations for oil and gas (O & G) and coal-bed methane (CBM) wells in Colorado in an effort to devise a standardized methodology to analyze the ecotoxicity and human health impact of chemicals. The chemicals constituents of HF fluids were analyzed for 40 O & G and 10 CBM wells for Weld and Las Animas counties, respectively, by extracting their well-specific HF fluid composition from the FracFocus HF chemical registry website. Using the USEtox human and ecotoxicological impact model we assessed all 184 detected chemicals, generated their categorization factors, and calculated their environmental impact per average well in each county in terms of the USEtox units of PDF.m3.day/MJ (potentially disappeared fraction of species at the endpoint level integrated over the freshwater volume (m3) and the duration of 1 day per megajoule (MJ)). We found that CBM HF wells (0.00546 PDF.m3.day/MJ) on average produced 12.6% greater impact from their chemicals than O & G wells (0.00485 PDF.m3.day/MJ). Impact was highly-sensitive to the fraction of HF fluid that returns to the surface as flowback, which average 17.5% for wells in Weld County and 61% for wells in Las Animas County.
Bibliography:
Includes bibliographical references.
System Details:
System requirements: Adobe Reader.
Statement of Responsibility:
by David Lawrence Zelinka.

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University of Colorado Denver Collections
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Auraria Library
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All applicable rights reserved by the source institution and holding location.
Resource Identifier:
985410477 ( OCLC )
ocn985410477
Classification:
LD1193.E53 2016m Z46 ( lcc )

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Full Text
AN ENVIRONMENTAL IMPACT ASSESSMENT OF CHEMICALS USED IN HYDRAULIC
FRACTURING OPERATIONS FOR A SELECTION OF OIL AND GAS WELLS COMPARED TO COALBED METHANE WELLS IN COLORADO by
DAVID LAWRENCE ZELINKA B.S., Purdue University, 2013
A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Masters of Science Civil Engineering
2016


This thesis for the Master of Science degree by David Lawrence Zelinka has been approved for the Civil Engineering Program By
Bruce Janson, Chair Arunprakash Karunanithi Azadeh Bolhari
Date: 22 July 2016


Zelinka, David Lawrence (M.S., Civil Engineering)
An Environmental Impact Assessment of Chemicals used in Hydraulic Fracturing Operations for A Selection of Oil and Gas Wells Compared to Coal-Bed Methane Wells in Colorado
Thesis directed by Associate Professor Arunprakash Karunanithi
ABSTRACT
This study estimates the environmental impact of chemicals used for hydraulic-fracturing (HF) operations for oil and gas (O&G) and coal-bed methane (CBM) wells in Colorado in an effort to devise a standardized methodology to analyze the ecotoxicity and human health impact of chemicals. The chemicals constituents of HF fluids were analyzed for 40 O&G and 10 CBM wells for Weld and Las Animas counties, respectively, by extracting their well-specific HF fluid composition from the FracFocus HF chemical registry website. Using the USEtox human and ecotoxicological impact model we assessed all 184 detected chemicals, generated their categorization factors, and calculated their environmental impact per average well in each county in terms of the USEtox units of PDF.m3.day/MJ (potentially disappeared fraction of species at the endpoint level integrated over the freshwater volume (m3) and the duration of 1 day per megajoule (MJ)). We found that CBM HF wells (0.00546 PDF.m3.day/MJ) on average produced 12.6% greater impact from their chemicals than O&G wells (0.00485 PDF.m3.day/MJ). Impact was highly-sensitive to the fraction of HF fluid that returns to the surface as flowback, which average 17.5% for wells in Weld County and 61% for wells in Las Animas County.
The form and consent of this abstract are approved. I recommend its publication.
Approved: Arunprakash Karunanithi


IV
CONTENTS
Chapter
1 Introduction and Background..............................................................1
1.1 Hydraulic Fracturing and Well Operations.............................................2
1.1.1 Denver-Julesburg Basin...........................................................2
1.1.2 Raton Basin......................................................................4
1.3 Goals of this research...............................................................4
2 Methodology..............................................................................7
2.1 Procedure for generating chemical categorization factors by data availability.......7
2.2 Acquiring chemical property data.....................................................9
2.2.1 Physio-chemical properties required for USEtox...................................9
2.2.2 Physio-chemical properties not required for USEtox..............................11
2.2.3 Environmental partitioning......................................................12
2.3 Determining the duration of the injection phase.....................................12
2.4 Determining flowback fraction.......................................................13
2.5 Calculating residence time..........................................................14
2.6 Calculating aqueous-based and evaporative masses....................................16
3 Functional Unit.........................................................................19
4 Hydraulic Fracturing Fluid Analysis.....................................................20
4.1 Traditional oil & gas wells in Weld County..........................................20


V
4.2 Coal-bed methane wells in Las Animas County.......................................22
5 Oil, Gas, and Water Production.........................................................24
5.1 Projection model...................................................................24
5.2 Energy produced by source..........................................................25
5.2.1 Weld County....................................................................25
5.2.2 Las Animas County..............................................................26
5.3 Produced water analysis............................................................27
5.3.1 Weld County....................................................................27
5.3.2 Las Animas County..............................................................28
6 Results and Discussion.................................................................30
6.1 Energy and produced water comparison...............................................30
6.2 Categorization factors.............................................................31
6.3 Environmental impact assessment....................................................41
7 Conclusions and Future Work............................................................54
References...............................................................................56
Appendix
A Annual Oil and Gas Production per Well..................................................59
B Annual Production Water.................................................................65
C Identified Chemicals
69


VI
FIGURES
Figure 1 Categorization factors methodology flowchart
7


vii
TABLES
Table
1 Assigned rate constants associated with BioWin3........................................10
2 Residence times and assumptions by county..............................................16
3 County-specific variables for calculating the evaporative mass per chemical............17
4 Average hydraulic fracturing fluid for a sample set of 40 traditional oil and gas wells in Weld
County....................................................................................21
5 Average hydraulic fracturing for a sample set of 10 coal-bed methane wells in Las Animas, County 22
6 Total natural gas and oil production per well in Weld County in MJ's....................25
7 Total natural gas production per well in Las Animas County in MJ's......................26
8 Total produced water generated in gallons per well in Weld County......................27
9 Total produced water generated in gallons per well in Las Animas County................28
10 Raw categorization factors for ecotoxicity............................................33
11 Environmental impact for Las Animas County by chemical................................42
12 Environmental impact for Weld County by chemical......................................48
13 Summary of impact for each county.....................................................52
14 Annual oil production values for wells in Weld County.................................59
15 Annual gas production values for wells in Weld County..................................61
16 Annual production values for wells in Las Animas County (natural gas only).............64
17 Annual produced water generated for wells in Weld County..............................65
18 Annual produced water generated per well in Las Animas County.........................68
19 All 184 chemicals detected in all 50 wells............................................69


EQUATIONS
viii
Air-water partitioning, Kaw...................................................................11
Average Impact per Well per Unit Energy (PDF.m3.day)/MJ.......................................46
Bioaccumulation factor in fish, BAFfish.......................................................10
Bio-transfer factor for meat, BTFmeat.........................................................10
Bio-transfer factor for milk, BTFmiik.........................................................10
Calculation of residence time.................................................................14
Chemical Evaporation Rate.....................................................................15
Chemical mass that remained in the pit, W,mass................................................17
Degradation rate in air, kdegA.................................................................9
Degradation rate in sediment, kdegsd..........................................................10
Degradation rate in soil, kdegsi..............................................................10
Degradation rate in water, kdegw (1/s)........................................................10
Dissipation rates in above-ground plant tissues, kdiSSp.......................................11
Flenry's constant, kH..........................................................................8
Organic carbon partitioning, Koc..............................................................11
Partitioning coefficient between dissolved organic carbon and water, Kdoc.....................10
Soil-water partitioning, Kd
11


1
1 Introduction and Background
Hydraulic fracturing is a process to create fractures in subterranean rocks by injecting water, a proppant, and chemicals under high-pressure to stimulate the flow of oil and/or gas. Directional drilling is similar to vertical (traditional) drilling except the drilling is capable of turning up to 90 degrees (horizontal); this enables an individual well to make viable previously unreachable deposits of oil and/or gas. The increased output and efficiency of wells using fracking and directional drilling are largely responsible for the natural gas boom since 20001.
According to FracFocus.org, which is the website of the national hydraulic fracturing (HF) chemical registry that discloses the chemicals and volumes of those chemicals for most wells in the United States, there are over 105,000 registered wells that use HF; only wells using HF are listed2. The total count for new oil and gas wells is estimated to be approximately 250,000 for the decade between 2000 and 2010, averaging 25,000 new wells a year; this figure does not include the wells drilled from 1947 to 2000. The beginning of the 2000's saw about 10% of the wells using horizontal drilling technologies, while the close of the decade saw that number climb to 60% indicating the widespread application of the technology. Similarly, HF became much more widespread: with 57% of all wells hydraulically fractured in 2005, a number that climbs to 78% to 99% in 2012, although exact figures are unknown3. Taking into account the global natural gas and oil industry, it is estimated that 90% of all new wells are hydraulically fractured4.
Colorado alone has in excess of 90,000 active wells of which a large fraction was estimated to be hydraulically fractured and/or horizontally drilled. 37% of all wells in Colorado are found in Weld County, but 50% of all producing wells, making it the most productive county in Colorado regardless of the indicator employed, which is why it was chosen as the county to be assessed5. The next most productive county is Garfield County at 17% of all Colorado wells. Some wells can be


2
fractured again to re-stimulate the flow of oil and/or natural gas after a well has already been fractured, following a production phase, with another production phase, but this process occurs on only wells that are assessed to be profitable with extra proven resources. The Denver-Julesburg (DJ) Basin underlying Weld County has the country's highest re-fracturing rate at 14% compared to 1% for the national average, but only one well was refractured in Las Animas out of the 50 wells in our assessment6.
In addition to traditional oil and gas wells, coal-bed methane (CBM) wells also, although not necessarily, use hydraulic fracturing. CBM is methane produced from trapped gas that is adsorbed into coal deposits7. Colorado produced more natural gas from CBM than any other state from the years of 2011-2014 (data is not available for later)8, and had more proven reserves than any other state with 32.5% (5,103 bcf) of the entire country's proven reserves9. There are far fewer wells for coal-bed methane than for traditional wells like in Weld County, but overall production is much lower as well. CBM occurs in the southern portion of Colorado in the Raton Basin, specifically in Las Animas County where the focus of our CBM research is located. Of the 211 CBM wells on the FracFocus Chemical Disclosure Database in Las Animas, Pioneer Natural Resources owned 140 of them, making them the largest operator by any measurement in that county and also the sole operator we used in our assessments. Weld County had 7,131 wells spread over dozens of operators2.
1.1 Hydraulic Fracturing and Well Operations
1.1.1 Denver-Julesburg Basin
Hydraulic fracturing is only one phase of the oil and gas well life cycle, and it has been used since 1947 in vertically-drilled wells in conventional oil and gas deposits. The advent of directional drilling (frequently referred to as just horizontal drilling) saw HF use increase greatly, and it now constitutes the vast majority of wells drilled today. Directional drilling and HF, when used in


3
conjunction, enables previously unreachable (unconventional) oil and gas deposits to be exploited, which has been the main source of the natural gas boom since 2000. Directional drilling enables well operators to exploit deposits that are otherwise impossible to reach, like deposits under large structures, on an angle, or otherwise located in areas not economically viable. HF fluids are composed of a base fluid, almost always water (80-98%), a proppant, almost always sand (5-20%), and a mixture of chemicals (1-2%)3.
The first stage in this oil and gas life cycle is the site assessment and preparation. Following site preparation, construction materials are brought to the site and the well and all associated roads, pits, and equipment are constructed and set up for the future phases. Wells are drilled vertically first, and when they reach the depth of the formation the drill head is turned to an angle, which can be up to 90 degrees, and direction that maximizes the contact with the oil and gas.
After the borehole is drilled at the well site, the hydraulic fracturing fluid is injected downhole. As the production phase starts, signified by the oil and gas extraction, the hydraulic fracturing fluid injection stops and the oil and gas begins to flow to the surface3 along with naturally-occurring radioactive materials (NORM's), inorganic ions, dissolved solids (TDS's), and other underground water with high pH, alkalinity, and other parameters10,11. This production phases lasts for the majority of the lifetime of the well, which ranges from five to 15 years, with 60 at the extreme end, but is much closer to the former value3. After the first year of production the annual recovery typically drops by 50-75%12, so that after about 10 years (less for many) most well production becomes negligable13. Following the useful economic life of the well, the site is closed, the well hole is plugged, and the site is returned to its original state as much as possible depending on the laws in the area3.
In addition to the aforementioned constituent's, large volumes of water that originated
underground return, which is classified as produced water. Water that returns originating during


4
the hydraulic fracturing injection phase above ground is called flowback water. These definitions are what will be used for this paper, but in the industry they are often used interchangeably or have slightly different definitions. A summary of these definitions can be found compiled by the EPA3.
1.1.2 Raton Basin
Hydraulic fracturing is often used for coal-bed methane (CBM), although it is not a requirement. The CBM layer is usually much shallower (0.8-1.2 km) than traditional oil and gas wells (2.0-2.3 km)3. CBM gas, unlike traditional hydraulically-fractured oil and gas wells, is not physically trapped within the fractures in the coal, but it is adsorbed within the coal7. In CBM, fractures might already exist within the coal, but HF is used to increase the fracture size; if the fractures do not exist HF creates them3. The HF fluid volume is less in CBM due to the shallower depth and less rigid geological formation in CBM areas. Additionally, a smaller variety of chemicals, generally, are required in lower volumes to stimulate these wells.
At this point, operations differ between the two basins. Under the high pressures, the gas remains adsorbed in the coal. Naturally occurring underground water is pumped out reducing the pressure in the coal, along with some of the injection chemicals. As the pressure decreases the methane desorbs from the coal and is pumped to the surface. Produced water is larger than in conventional hydraulically-fractured wells, like in the DJ Basin. In the DJ Basin produced water falls off proportionally to the oil and gas produced, but in CBM deposits produced water is inversely-proportional to gas production7.
1.3 Goals of this research
Determining the human health and ecotoxicity impacts requires the use of USEtox14-17, which is a life cycle impact model based on scientific consensus for generating midpoint categorization factors for human and ecotoxicological impacts15. Most chemicals have not been previously assessed, so these had to be customized and manually generated; this was one of the


5
main goals of this research. Data acquired for each chemical was inputted into USEtox to generate the impacts. The output was applied to known chemical masses found in the 50 wells. Due to the lack of data regarding the human toxicity, it was decided to omit human toxicity and just generated the ecotoxicity values.
Most research does not focus on the impacts of the unknown chemicals; they primarily look at the entire life cycle of and oil and gas well while focusing on water, energy, and emissions. Of the papers that have looked at the chemicals most use only the chemicals that are known, while other look at chemicals that have already been identified, while ignoring chemicals with unknown properties18. Various entities, especially the United States Environmental Protection Agency (EPA)3, the United States House of Representatives19, and FracFocus.org20, have identified well over 1,000 different chemicals commonly used in hydraulic fracturing operations, although many chemicals are unknown because they are used relatively infrequently; their combined impacts when summed over all wells merit analysis. Some studies use these lists as the main source for the chemicals in their analysis, but they do not identify chemicals themselves and rely on external sources, as was the case in Impact of Shale Gas Development on Water Resources A Case Study in Northern Poland18. Out of the chemicals identified by the EPA only 37 of the nearly 184 (21%) chemical were found in use in the 40 wells in Weld County. Relying on these external sources is a good starting point, but they do not represent a complete list the chemicals found in hydraulically-fractured wells. Absent chemicals are generally uncommon and these lists usually focus on chemicals common to HF and from locations other than Colorado, primarily the Marcellus Shale. As a result, many of the assessments are high-level and not well-specific.
We made our assessments by focusing on specific wells to acquire high resolution data that can be applied to less-studied locations, like Weld County for our research. Many of these
uncommon chemicals are lacking physio-chemical property data, and even more are lacking toxicity


6
and human health data3, and very few papers have had the main goal to find these data18,21. Chemicals that have not been analyzed in detail, representing the majority of our chemicals, require prediction software or empirical studies that come with their own problems. Prediction software are best guesses and studies per chemical are costly and time-consuming, but they are the only two ways to acquire the information to generate the categorization factors, or at the least, bring about understanding of the chemical. Our standardized methodology could be applied by other researchers to expand the knowledge of chemicals and HF impacts on local levels (well or site specific).
The Niobrara and Raton basin's both produced natural gas and use hydraulic fracturing in Colorado; the only difference is that the Niobrara Basin produced oil and gas from traditional hydraulic fractured wells while the Raton Basin produced coal and almost exclusively gas from coal deposits.


7
2 Methodology
2.1 Procedure for generating chemical categorization factors by data availability
Figure 1 Categorization factors methodology flowchart Due to the varied mixture of constituent chemicals in each individual well's hydraulic
fracturing fluid, compounds were found that had all degrees of available data, ranging from nothing
and unknown chemicals to the exact TRACI categorization factors necessary to run an analysis. That databases used to acquire the experimental values were Chemicalize22, PubChem23, and ToxNet24, shown as green boxes in Figure 1. Various models were used to fill in data gaps USEtox1415, US


8
EPA Estimation Program Interface (EPISuite)25, and ECOIogical Structure Activity Relationships (ECOSAR)26'27 when experimental data did not exist, which can be seen in Figure 1 as orange boxes.
From the original inventory of 184 identified chemicals, three unique groups of substances were recognized, when organized by data availability.
I. 44 chemicals had their categorization factors complete in TRACI, so nothing extra was required.
II. Five chemicals were not in TRACI, but were in USEtox, so calculating the categorization factors was straight-forward and involved only running the USEtox model.
III. 135 chemicals were not in neither TRACI or USEtox, so their chemical properties and toxicity data had to be manually located and inputted into the USEtox model to generate their categorization factors.
In order to generate the remaining 135 categorization factors, the remaining chemicals were further reduced to three subgroups.
I. 81 chemicals were able to have their factors generated, as their properties were available through experimental data or through the EPI Suite and ECOSAR prediction models.
II. 21 chemicals of these were very close or identical to other known chemicals. The substitute chemical data was applied to these chemicals.
III. The remaining 33 were ambiguously-named chemicals (surfactant, nonhazardous, inorganic base, proprietary, etc.), were lacking a CAS number, or were otherwise not able to be identified. For these chemicals the average categorization factors were applied from all the chemicals that could be identified. This categorization factors for these 33 were all the same as a result of applying the average.
To maintain a standard procedure for each chemical all chemicals were run through the USEtox
model. Chemicals that existed in the USEtox database and in our database were chosen at random


9
and then their categorization factors were generated. These values were checked against the USEtox database for validity, and if they were close to the values found in the database, it was assumed that all chemicals would yield close factors.
2.2 Acquiring chemical property data
In addition to the specific format and units USEtox requires for input, there are many formulae recommended to further fill in data gaps in a fashion that standardizes the generation of categorization factors28,29. Standardized formulae and methodologies aid in reducing possible outliers and variability in preliminary values with data that is already inherently inexact or missing due to large assumptions and data prediction from the lack of experimental data. All formulae, methodologies, and assumptions were compiled to have a standardized algorithm for acquiring missing data. In all cases, experimental data is preferred before using prediction software and formulaic assumptions. The assumptions below are to be used only if experimental data cannot be found.
2.2.1 Physio-chemical properties required for USEtox
Molecular weight, MW (g/mole): can be found by summing the molecular weight of all atoms Octanol-water partitioning, Kow (dimensionless): predict using the Fragment method in EPISuite Henry's constant, kH (Pa-m3/mole): if left blank USEtox automatically calculates internally using the formula. The additional conversion factors are added only to show that the units are not the same, but coincidentally the numbers cancel out, so the formula will work without the conversions.
Vapor pressure, vp (Pa): predict using EPISuite; for solids the Modified Grain method should be used, and for liquids and gases either the Antoine or the Modified Grain methods could be used
(1)


10
Water solubility, S0I25 (mg/L) predict using EPISuite which requires K0w and melting points; USEtox does not calculate water solubility and must be user entered; rearranging the Henry's constant formula can be used to find the water solubility, but care should be used to avoid circle logic; only if experimental data can be found or if EPISuite has a reasonable result should the rearranged Henry's
constant formula be employed
Degradation rate in air, kdegA (1/s): predict using the OVERALL OH Rate Constant (kOH) under AopWin in EPISuite, which is multiplied by the constant 1.5 x 10s.
k
degA
= [OH] x kOH
cm
molecules s
kdegA = I 1-5 X 106
molecules
L- / / t
x kOH
em
molecules s
k,
degA
= 1.5 x 106 x kOH (s_1)
(2a)
(2b)
(2c)
Degradation of water, sediment, and soil: find the Biowin3 (Ultimate Survey Model) and, neglecting the values, use the time range to match the assigned rate constant in Table 1.
Table 1 Assigned rate constants associated with BioWin3
BIOWIN3 OUTPUT ASSIGNED RATE ___________________CONSTANT (S'1)
HOURS 4.7 x 10'5
HOURS TO DAYS 6.4 x 10 s
DAYS 3.4 x 10 s
DAYS TO WEEKS 9.3 x 10'7
WEEKS 5.3 x 10'7
WEEKS TO MONTHS 2.1 x 10'7
MONTHS 1.3 x 10'7
RECALCITRANT 4.5 x 10 s
Once the rate constant has been identified the formulae below were used to find the degradation rates for each environmental compartment Degradation rate in water, kdegw (1/s)
kdegw = Assigned Rate Constant (3)
Degradation rate in soil, kdegsi (1/s)
kdegsi = Assigned Rate Constant/2
(4)


11
Degradation rate in sediment, kdegsd (1/s)
kdegsd = Assigned Rate Constant/9 (5)
2.2.2 Physio-chemical properties not required for USEtox
The following assumptions are for data that are not required to generated USEtox categorization factors, but do enhance the validity of the output, especially for chemicals lacking experimental data. For any data not shown, QSAR values are preferred, but can be left blank if no experimental data exists.
Partitioning coefficient between dissolved organic carbon and water, Kdoc (L/kg): if left blank USEtox automatically calculates internally using the formula
^doc ~ 0.08Kow; for
Kow < 7 5 (6)
Bio-transfer factor for meat, BTFmeat (day/kg meat): if left blank USEtox automatically calculates internally using the formula30
BTFmeat = io-7-735+1-0331gO Bio-transfer factor for milk, BTFmiik (day/kg milk): if left blank USEtox automatically calculates internally using the formula30
BTFmilk = io-81+1g(W) (8)
Bioaccumulation factor in fish, BAFfiSh (L/kg fish): if left blank USEtox automatically calculates internally using the formula
BAFfish = 0.05Kow;for Kow < 9 (9)
Dissipation rates in above-ground plant tissues, kdiSSp (1/s): if left blank USEtox automatically calculates internally using the formula
kdiSSP ~ ^AkdggSi (10)


12
2.2.3 Environmental partitioning
Organic carbon partitioning, Koc (kg/L): predict using the Molecular Connectivity Index (MCI) in EPISuite, or if it is left blank USEtox automatically calculates internally using the formula
Koc = 1-26 Kow + 0.81 (11)
Soil-water partitioning, Kd (kg/L): if experimental data does not exist than the following formula is to be used; foc is the fraction of organic carbon and is assumed to be 0.02
Kd = Kocfoc = 0.02 Koc (12)
Air-water partitioning, Kaw (dimensionless): if experimental data does not exist than the following formula is to be used
KfJAAJ
Kh Pa m3 mol
R m3 Pa mol K Tenv [K]
0.1203Kh
(13)
2.3 Determining the duration of the injection phase
The time when the hydraulic fracturing injection phase ends and the production phase begins is not a discrete point. For a similar reason that differentiating flowback from produced water is difficult, so is the point at which the two phases separate. The two phases are fundamentally interconnected so no one distinct definition exists to delineate the two31. Multiple ways to determine when the injection phase turns into the production phase are used: the time required to injected all the hydraulic fracturing fluid; the time until produced water is greater than flowback water; the point at which oil and gas collection starts3,31.
The duration of the injection phase is the point when the hydraulic fracturing begins to be pumped underground to when the production phase starts, using one of the previous definitions. This information was not available per well and is at best difficult to find per deposit, so generic
industry values were used. 14 days is the most cited in literature, so we used this value whenever


13
injection phase duration was needed for shale, specifically for calculating disposal pit residence times3,31'32. The only available data for injection duration for CBM was analyzed for a 19-day period, so this value was used for CBM wells7.
2.4 Determining flowback fraction
Although the fraction of injected hydraulic fracturing fluid that returns as flowback water can be highly variable, this amount his correlated to the deposit in which the a well is drilled. In a selection of nine deposits the EPA has shown a list of low and high estimates for flowback water for an average well located on each of these deposits. Values range from 6-11% on the low end and 5-48% on the high end. More specifically, Niobrara, above which Weld County sits, is listed as having a range between 8 and 27%, with an average at 17.5%. This value is used through this paper as a the constant flowback fraction since a well-specific data to calculate flowback fraction is currently not possible to ascertain3. Most wells will have a flowback ratio much closer to the low estimate, which in the case of the Niobrara would most likely be 10%, but there is not enough data so we went with the average. Produced water is subject to even higher variations then flowback water. By definition flowback water can't exceed the amount that enters the well, but produced water can range from 10 to 300% of the infected water volume depending on the life of the well31.
Data for flowback rates for the Raton Basin and coalbed methane, in general, are sparse. A 2004 EPA study on CBM7 finds one paper, Palmer et at., 1991, that has specific flowback values dating back to 1991. Fortunately, the EPA does a literature review, which corroborates the validity of data from that study. We concluded the values from that paper will suffice for our analysis due to low data availability. The flowback rate was calculated for a duration of 19 days, generating a recovery rate of 61%33. The 19-day value is related to the injection duration of the fracking fluids, t; in the residence time calculation in Section 2.5 Calculating residence time. The flowback rate
depends on the duration the fluid is recovered a higher duration will yield a higher flowback rate -


14
and Palmer et al. states that flowback recovery rates were predicted to be as high as 82% for longer recovery periods. We assumed the injection duration and the recovery duration to be the same, but the study differentiates the two. An injection duration of 14 days, which is on par with our assumed injection duration for the wells in Weld County, if applied to CBM wells, would have a lower flowback volume. Ideally we would calculate the flowback fraction based on 14 days, but there were not sufficient data points to extrapolate a flowback ratio for a 14-day injection duration. Our residence time calculation does take into account the duration of injection, but the limited data is the main crux to our calculations.
2.5 Calculating residence time
Residence time (t, days') refers to the average duration that a chemical is likely to remain in the storage ponds until it is removed. The residence time is assumed to be constant for all chemicals in the same pond. It is used to determine how long the chemicals are in contact with the environment; the longer a chemical is in the environment the greater its potential impact.
Additionally, it was assumed that the pits were always full, implying that the flow rate entering the pit equals the flow rate leaving the pit. Companies will want to maximize their profits, and a pit that is not filled to capacity was not minimizing its expenses, thereby reducing the company's profits. This assumption simplified the calculations. The general residence time formula is governed by the flow rate out of the pit, which is further reduced to four separate flow rates: evaporation, percolation, truck removal, and pipeline removal. Determining these flow rates required data that was either difficult to get, required too many assumptions, or did not exist. Since the flow rates in and out were assumed to be equal, we could rely solely on the flow rate into the pit.
Information regarding the disposal pits is required for generating the residence time. Data for pits in each county with sufficient production and volume information were extracted. The


15
length, width, and depth were used to determine volumes (Vp in m3), which was the key piece of information required from the pits.
Calculating residence time (r in days) required [1] the volume of the storage pits (Vp in m3), discussed in; [2] the duration of that injection (t; in days), discussed in 2.3 Determining the duration of the injection phase ; [3] the fraction of the hydraulic fracturing fluid that returned to the surface (/ is dimensionless), discussed in 2.4 Determining flowback fraction; and [4] the injection volume of the hydraulic fracturing fluid (VHFF in m3). Equation 14a shows the flow rate in based residence time formula, which is the ideal equation to use but information on operations and
specific data was not available. The variables in the equation, Qtruck = which should be
used when all the data for the flow rate out of the pit, represents the average capacity (C in gallons) of the trucks that take away the used fracking fluid and the rate constant (k in days-1). Equation 14b show the flow rate out based residence time formula used for our calculation of residence time.

Vn
t =
Vv
Qout Qevav ~b Qperc "h Qtruck "h Qpipe Qevap "h Qperc "h + Q
cpipe
T =
Vp Vptj
(14a)
(14b)
Qin f VhFF
Table 2 shows the specific variables from Equation 14b that were used for the calculation of residence time. The largest sources of variability came from the injection duration (tj) and the flowback fraction (/), especially for Las Animas County. Residence time is proportional to the pit volume and injection duration and is inversely proportional to the flowback fraction and the hydraulic fracturing fluid volume (VHFF).


16
Table 2 Residence times and assumptions by county
Weld County Las Animas County
Vp (m3) 2775.03 389.95
tj (days) 14 19
/(-) 0.175 0.61
I/HFF(m3) 7332.79 295.09
r (days) 30.3 41.2
2.6 Calculating aqueous-based and evaporative masses
For calculating environmental impact, it is important to know which the fraction of each chemical that ends up in each compartment. Traditional environmental engineering dictates the use of a two film model to determine the rate at which each volatilizes into the air, the mass that remains in the pit, and the mass that absorbs into the soil. This calculation requires computing or determining: the concentrations in the air, water, and soil compartments; the gas and liquid phase mass transfer coefficients; the air-water partition coefficient; the thickness of the film on the surface of the pond; and the diffusion coefficients of each chemical in the air and water phases. Each variable requires other input variables augmenting the complexity of the calculations. With greater complexity propagation of errors could start to become a potential problem; with more input variables and assumptions, data accuracy and multiple unknowns could affect the precision of the final values. With 184 chemicals these calculations can take a lot of time, effort, and the calculations lend themselves to generating too many errors from low precision and unknowns.
It was decided to try and simplify this process. In Correlation of Chemical Evaporation Rate with Vapor Pressure a simple and appropriate method to calculate the mass that evaporates from liquid pools was found. Equation 15a shows the original equation from the paper34. Equation 15b


17
(with units 7^) is equivalent to Equation 15a (with unitsbut with the coefficient altered
V m^dayj \ m^sj
to reflect the appropriate units.
kg
m2s
kg
= 4.07 X 107 pv MW = 3.52 X 10~spvMW
(15a)
(15b)
mass [m2day\
At this point the equations differ by county due to the differences in the average disposal pits used within each county. From data extracted from the Colorado Oil and Gas Conservation Commission (COGCC) website35 we found that the average surface area for storage pits in Weld County (designated by subscript W) is 1041.2 m2 and is 212.2 m2 for Las Animas County (designated by subscript LA). The surface area was found by dividing the volume of the pits (Vp) by their depth, which were both readily available. From Section 2.5 Calculating residence time we know that the residences times are 30.3 and 41.2 days for Weld County and Las Animas County, respectively, shown in Table 3.
Table 3 County-specific variables for calculating the evaporative mass per chemical
Weld County Las Animas County
(m3) 1041.2 212.2
r(days) 30.3 41.2
Pv (Pa) chemical dependent
MW ( 3) chemical dependent
Equation 15c is the generic equation that can be applied to any chemical in any location. Inserting the values from Table 3 into Equation 15c generates the county-specific formulae in Equation 15d and Equation 15e, where subscript i denotes the county.
Time is assumed to be the residence time for the injection phase, since all the chemicals
being assessed are injected and most comes out in that time.


18
Units are important as the coefficients are unit dependent: vapor pressure (pv) is in pascals
(Pa); molecular weight (MW) is in grams per mole surface area (zls) is in meters squared
(m2); and residence time (t) is in days.
Emassikg] = 3.67 X 10-5 pv MW As>i Tt (15c)
Emass,w[kg] 1.11 pv x MWX (15d)
Emass,LA[kg] 0.31 pvx MWX (15e)
Equation 15d and Equation 15e were then applied to each chemical for their respective counties to calculate the mass of a given chemical that volatilizes into the atmosphere. Once evaporative masses were found for each chemical (designated by subscript x), that value was subtracted from the entire mass that flowed out of the pit (/mx) the pit to find the chemical mass that remained in the pit, shown in Equation 16 and Equation 16b for their respective counties.
Wmass.w [kg] = fmx 1.11 pViX MWX (16a)
^'mass,LA [^P1] f^-x 0.31 pvx MWX
(16b)


19
3 Functional Unit
A typical hydraulically fractured well will have a base fluid (water 93% of the time3), proppant, and at least a dozen chemicals. Exact chemicals and quantities of each vary greatly between individual wells depending on specific features of the local geology, depth of the deposit, and a host of other minor factors. The chemicals are delineated between functional categories to serve the various function required by the geology. Additionally, the composition of the injection fluids for regular oil and gas wells will differ from coal-bed methane (CBM) wells in various ways, analyzed in section three. In order to facilitated a comparative analysis between traditional oil and gas wells and CBM wells a functional unit is required. Since the goal of these wells is to produce a fuel, the chosen functional unit was the megajoule (MJ).
Wells in Weld County, produced oil and gas, but wells in Las Animas county only produced gas. All volumes of oil and gas were converted to their energy equivalents in terms of MJ. From here each well could be reduced to MJ output. The environmental impact from chemicals and produced water generated were divided by the total energy, or total projected energy, produced from the wells.
The environmental impact from chemicals had their own functional units. Their masses were multiplied by their endpoint ecotoxicity characterization factors to determine their base impact in units of PDF m3 day, which USEtox reduces to comparative toxicity units (CTUs). The summation of all chemical impacts over the quantity of wells yields the total impact. Finally, this impact was divided by the average energy output of the wells in each county to ascertain the
^ ... T| . ^ / PDF-m3-day CTU\ ... ...
comparative impact per MJ. The impact per unit energy (^-----= would show which
source was better for the environment in terms of chemicals.


20
4 Hydraulic Fracturing Fluid Analysis
4.1 Traditional oil & gas wells in Weld County
This analysis focuses on the chemicals, which range from 14 to 51 separate chemicals per well, according to our findings. These functions are grouped into about 18 categories of which a chemical could fall into multiple categories, but generally does not. Of the 184 chemicals we identified only 24 chemicals were used in multiple groups, while the rest only had one function.
The base fluid is used to suspend the chemicals and the proppant, which holds open the fractures in the rock to facilitate the flow of oil and gas to the surface. Acids help dissolve rock and initiate cracks to start the oil and gas production. Corrosion inhibitors protects the pipe from corroding due to other chemicals in the fluid. Crosslinkers increase viscosity as temperature increases and assist with proppant transport downhole. Biocides kill bacteria which can corrode and damage the pipe. Breakers delay the breakdown of gels when needed, reverse crosslinking, reduce viscosity, and remove polymers from new fractures to more easily allow the production gas to flow. Crosslinkers and breakers worked against each other, but depending on phase of the well different properties are desired in the fluid. Friction reducers help to increase the fluid flow rate, increasing pump efficiency. Gels thicken water to suspend the proppant and increases the viscosity of the entire fluid. Iron controllers prevent precipitation of iron oxide compounds. Surfactants reduce surface tension of the fluid and improve the fluid recovery once the hydraulic fracturing phase is complete. pH reducing agents/buffers maintain the effectiveness of other chemical categories, specifically crosslinkers. Clay/shale stabilizers/controllers prevent the clay/shale from swelling into the fluid and coming to the surface and/or reducing the efficiency of the entire process. Most of these categories are used for every HF job, but not necessarily20,36.


21
The categories we identified are not verbatim the exact categories listed on fracfocus.org and other sources, due to semantics employed by these various sources, but the functions remain the same. Fluids for each well differ by chemicals, chemical masses, categories due to chemical availability, geological formation, and other related factors. The average fluid of the 40 oil and gas wells in Weld County can be seen \nTable 4 Average hydraulic fracturing fluid for a sample set of 40 traditional oil and gas wells in Weld County Table 4, which is corroborated by the values mentioned in the literature. The chemicals by mass, represent 1.065% of the total mass of the hydro-fracking fluid.
Table 4 Average hydraulic fracturing fluid for a sample set of 40 traditional oil and gas wells in Weld County
CATEGORY MASS, TOTAL (KG) MASS, AVERAGE PER WELL (KG) MASS, TOTAL (%)
BASE FLUID 293,271,739 7,331,793.5 92.436%
PROPPANT 20,618,054 515,451.3 6.499%
FRICTION REDUCER 1,004,824 25,120.6 0.317%
GEL 947,943 23,698.6 0.299%
ACID/SOLVENT 383,821 9,595.5 0.121%
BUFFER 200,912 5,022.8 0.063%
SURFACTANT 153,485 3,837.1 0.048%
CLAY STABILIZER 141,192 3,529.8 0.045%
BREAKER 140,926 3,523.1 0.044%
ADDITIVE 108,856 2,721.4 0.034%
CROSSLINKER 100,564 2,514.1 0.032%
PROPRIETARY OR UNKNOWN 69,448 1,736.2 0.022%
EMULSIFIER 48,033 1,200.8 0.015%
BIOCIDE 30,464 761.6 0.010%
CORROSION INHIBITOR 23,442 586.1 0.007%
ACTIVATOR 18,349 458.7 0.006%
CONCENTRATE 5,264 131.6 0.002%
NON-EMULSIFIER 2,066 51.6 0.001%
IRON CONTROL 256 6.4 <0.001%
There is a wide range of chemicals used in the hydraulic fracturing phase including acids, alcohols, and aromatic hydrocarbons, which is not an exhaustive list, that are known carcinogens (cancer causing among humans) and environmental contaminants exhibiting high ecotoxicity values.
Additionally, a large selection of the detected chemicals has ecosystem or human health effects that


22
are completely unknown because the chemicals have never been empirically studied; many of those chemicals have at least some physio-chemical properties that are also unknown. This implies that the chemicals being injected underground are unstudied and not analyzed for danger prior to being used. The majority of the HF fluid remains underground; little research is done on the impact of chemicals that remain underground, and they are also outside of the scope of this assessment.
The fraction of fluid that does not come to the surface various by geological formation, but common figures range from 5 to 75% of that which is initially injected that returns; the DJ Basin recovers between 8 and 27%3. The explosive growth of HF has brought hundreds of chemicals to commercial use that were previously rarely used, if at all. These chemicals require research into their impact on the ecosystem and human health. We identified 184 chemicals used in only 50 wells (there are over 30,000 wells in Weld County alone)5, of which only a quarter have had complete assessments undertaken; the remaining chemicals have not been extensively studied.
4.2 Coal-bed methane wells in Las Animas County
The average hydraulic fracturing fluid for coal-bed methane wells differ noticeably from those of traditional oil and gas wells. The main differences are the inclusion of the foaming category and the relatively smaller contributions from the base fluid and chemicals. The foaming agent could be either a carbon dioxide or nitrogen based foam, with negligible other chemicals. In the case of Las Animas County, all wells employed a nitrogen foaming agent, which constituted 99.74% of all the chemicals by mass in the foam category.
Table 5 Average hydraulic fracturing for a sample set of 10 coal-bed methane wells in Las Animas, County
CATEGORY MASS, TOTAL (KG) MASS, AVERAGE (KG) MASS, TOTAL (%)
BASE FLUID 2,950,906.554 295,090.655 60.27667%
PROPPANT 1,223,623.485 122,362.348 24.99434%
FOAMING AGENT 712,914.388 16,579.404 14.56234%
GEL 4,457.891 445.789 0.09106%
ACID 2,949.507 226.885 0.06025%


23
CATEGORY MASS, TOTAL (KG) MASS, AVERAGE (KG) MASS, TOTAL (%)
PROPRIETARY OR UNKNOWN 563.149 33.126 0.01150%
BREAKER 176.921 7.372 0.00361%
CORROSION INHIBITOR 4.384 0.548 0.00009%
SCALE INHIBITOR 3.306 0.301 0.00007%
IRON CONTROL 3.262 1.631 0.00007%


24
5 Oil, Gas, and Water Production
With the condition that they were already hydraulically fractured, wells were chosen at random, which meant that they were at various stages of production. Of the wells in Weld County, nine (22.5%) of the 40 were completed, while the remainder were currently producing. Las Animas County had only one (10.0%) well that was no longer producing of the 10. Production data was extracted for all wells between the years of 1999 and 2015, inclusively.
5.1 Projection model
The 50 wells used for this paper are at various levels of production: some are no longer producing; some have just begun to produce; and one well was refractured. Incomplete wells needed to have the lifetime production estimated to increase the accuracy of the assessment. In order to do this our procedure began with standardizing the annual production by production year not actual calendar year. Regardless of the year a well began producing year (PY) 1 for each well was the first year it began producing. For example, the well with API designation 05-71-08280 began producing in 2005, and the well with API designation 05-71-09885 began producing in 2012. They will both have their production data for 2005 and 2012, respectively, begin in the same column, production year 1. Once the data was organized by production year, we found the average growth per production year was found by dividing the averaging available data from the previous year by the average available data for the current year. This growth rate was applied to each year with missing data, thereby filling the data gaps. The lifetime of each well was assumed to be the lifetime of the longest producing well in the data 17 years for Weld County and 11 years for Las Animas County. The following charts will show the total output, while the supplementary data will show all the year's data. The Model Reliance depict the ratio of MJ's that come from empirical data
over the MJ's that came from the projected values; a value of 0.0% means that all values for that


25
well came from the data and not from the projections. Values in red are derived from the model; all others are from the data.
5.2 Energy produced by source
5.2.1 Weld County
Table 6 Total natural gas and oil production per well in Weld County in MJ's
well API Natural Gas Oil Total
Total, Empirical Total, Model Model Reliance Total, Empirical Total, Model Model Reliance
12459 558.597E+6 558.597E+6 0.0% 143.526E+6 143.526E+6 0.0% 7.02E+08
12629 215.020E+6 215.020E+6 0.0% 104.934E+6 104.934E+6 0.0% 3.20E+08
19794 199.915E+6 204.445E+6 2.2% 256.493E+6 258.832E+6 0.9% 4.63E+08
20613 72.478E+6 110.830E+6 34.6% 118.730E+6 147.489E+6 19.5% 2.58E+08
21028 379.533E+6 426.617E+6 11.0% 91.811E+6 115.059E+6 20.2% 5.42E+08
21514 150.285E+6 251.671E+6 40.3% 78.346E+6 103.228E+6 24.1% 3.55E+08
24914 189.506E+6 190.495E+6 0.5% 161.335E+6 161.440E+6 0.1% 3.52E+08
25988 110.400E+6 118.475E+6 6.8% 110.410E+6 111.769E+6 1.2% 2.30E+08
29021 74.581E+6 204.070E+6 63.5% 99.495E+6 252.167E+6 60.5% 4.56E+08
29022 63.050E+6 157.910E+6 60.1% 79.294E+6 172.670E+6 54.1% 3.31E+08
30906 4.628E+6 10.117E+6 54.3% 20.207E+6 34.072E+6 40.7% 4.42E+07
31642 103.731E+6 205.561E+6 49.5% 410.744E+6 736.471E+6 44.2% 9.42E+08
32368 21.656E+6 93.059E+6 76.7% 307.602E+6 465.909E+6 34.0% 5.59E+08
32457 161.579E+6 388.886E+6 58.5% 365.410E+6 703.404E+6 48.1% 1.09E+09
32795 92.187E+6 313.080E+6 70.6% 69.053E+6 162.013E+6 57.4% 4.75E+08
33361 133.826E+6 436.662E+6 69.4% 323.203E+6 687.864E+6 53.0% 1.12E+09
34060 123.556E+6 379.899E+6 67.5% 33.905E+6 117.415E+6 71.1% 4.97E+08
34062 97.856E+6 277.620E+6 64.8% 129.186E+6 208.004E+6 37.9% 4.86E+08
34066 86.789E+6 285.815E+6 69.6% 26.234E+6 71.809E+6 63.5% 3.58E+08
34068 99.381E+6 291.256E+6 65.9% 37.760E+6 94.863E+6 60.2% 3.86E+08
34509 76.525E+6 274.293E+6 72.1% 79.618E+6 179.884E+6 55.7% 4.54E+08
36279 147.655E+6 400.241E+6 63.1% 290.594E+6 420.949E+6 31.0% 8.21E+08
36468 93.574E+6 248.438E+6 62.3% 239.736E+6 358.444E+6 33.1% 6.07E+08
36853 497.120E+6 1.885E+9 73.6% 598.875E+6 962.191E+6 37.8% 2.85E+09
36855 455.698E+6 1.470E+9 69.0% 786.279E+6 1.307E+9 39.9% 2.78E+09
36856 336.630E+6 1.028E+9 67.3% 596.202E+6 1.031E+9 42.2% 2.06E+09
37401 127.077E+6 359.218E+6 64.6% 381.604E+6 712.523E+6 46.4% 1.07E+09
37728 238.715E+6 778.178E+6 69.3% 530.612E+6 937.102E+6 43.4% 1.72E+09
37790 100.476E+6 287.224E+6 65.0% 294.497E+6 460.504E+6 36.0% 7.48E+08
38169 85.260E+6 264.176E+6 67.7% 321.618E+6 523.673E+6 38.6% 7.88E+08
38415 335.736E+6 1.130E+9 70.3% 630.780E+6 1.015E+9 37.9% 2.15E+09


26
Natural Gas Oil
Well API Total, Total, Model Total, Total, Model Total
Empirical Model Reliance Empirical Model Reliance
38416 610.800E+6 2.456E+9 75.1% 1.186E+9 2.217E+9 46.5% 4.67E+09
39006 169.136E+6 489.230E+6 65.4% 347.179E+6 530.227E+6 34.5% 1.02E+09
39008 182.190E+6 608.387E+6 70.1% 313.524E+6 522.001E+6 39.9% 1.13E+09
39009 176.609E+6 477.886E+6 63.0% 315.512E+6 490.432E+6 35.7% 9.68E+08
39010 146.611E+6 431.788E+6 66.0% 262.005E+6 428.621E+6 38.9% 8.60E+08
39088 52.197E+6 499.597E+6 89.6% 151.816E+6 556.777E+6 72.7% 1.06E+09
39603 192.787E+6 1.845E+9 89.6% 187.128E+6 686.284E+6 72.7% 2.53E+09
40388 125.738E+6 1.203E+9 89.6% 141.892E+6 520.384E+6 72.7% 1.72E+09
40503 83.665E+6 800.784E+6 89.6% 170.127E+6 623.931E+6 72.7% 1.42E+09
Average Empirical Total 1.793E+08 1.079E+10 269.831E+6 10.793E+9 1.03E+09 4.14E+10
Average Annual Change 107.98% 94.11%
. Average Model 5.514E+08 483.432E+6 1,034,841,937
Total 2.206E+10 19.337E+9 41,393,677,463
Average Annual Change 109.60% 95.03%
Average Model Reliance
5.2.2 Las Animas County
Table 7 Total natural gas production per well in Las Animas County in MJ's
Well API Total, Empirical Total, Model Model Reliance
08280 1.3E+9 1.3E+9 0.0%
08908 416.8E+6 493.4E+6 15.5%
09386 229.2E+6 417.8E+6 45.1%
09490 126.4E+6 703.1E+6 82.0%
09782 15.9E+6 52.1E+6 69.5%
09871 459.6E+6 2.4E+9 80.5%
09874 596.0E+6 3.5E+9 82.9%
09878 59.5E+6 195.3E+6 69.5%
09885 457.5E+6 1.2E+9 61.0%
09898 1.1E+9 4.7E+9 75.8%
Average Empirical Total 484.7E+6 4.8E+9
Average Annual Change 138.4%
Average Model Total 1,493,937,492 14,939,374,916
Average Annual Change 140.0%
Average Model Reliance 67.56%


27
5.3 Produced water analysis
5.3.1 Weld County
Table 8 Total produced water generated in gallons per well in Weld County
Well API Total, Empirical Total, Model Model Reliance
12459 374.850E+3 374.850E+3 0.0%
12629 239.274E+3 239.274E+3 0.0%
19794 11.718E+3 55.993E+3 79.1%
20613 112.476E+3 179.921E+3 37.5%
21028 347.130E+3 491.858E+3 29.4%
21514 140.364E+3 185.039E+3 24.1%
24914 42.294E+3 42.294E+3 0.0%
25988 52.416E+3 226.670E+3 76.9%
29021 35.574E+3 93.391E+3 61.9%
29022 45.570E+3 45.570E+3 0.0%
30906 11.760E+3 153.587E+3 92.3%
31642 2.122E+6 4.328E+6 51.0%
32368 1.519E+6 2.063E+6 26.4%
32457 781.158E+3 2.593E+6 69.9%
32795 83.622E+3 118.247E+3 29.3%
33361 480.354E+3 1.106E+6 56.6%
34060 80.304E+3 221.529E+3 63.8%
34062 388.122E+3 437.196E+3 11.2%
34066 78.498E+3 171.194E+3 54.1%
34068 143.976E+3 214.861E+3 33.0%
34509 247.968E+3 342.300E+3 27.6%
36279 517.482E+3 628.387E+3 17.6%
36468 861.294E+3 1.565E+6 45.0%
36853 2.881E+6 3.341E+6 13.8%
36855 3.820E+6 4.453E+6 14.2%
36856 2.990E+6 3.498E+6 14.5%
37401 1.297E+6 2.110E+6 38.6%
37728 966.840E+3 1.278E+6 24.4%
37790 422.730E+3 483.025E+3 12.5%
38169 473.424E+3 551.632E+3 14.2%
38415 91.728E+3 154.808E+3 40.7%
38416 140.238E+3 234.173E+3 40.1%
39006 1.025E+6 1.309E+6 21.7%
39008 1.116E+6 1.418E+6 21.3%


28
Well API Total, Total, Model
Empirical Model Reliance
39009 1.017E+6 1.278E+6 20.4%
39010 922.026E+3 1.173E+6 21.4%
39088 1.044E+6 2.968E+6 64.8%
39603 865.998E+3 2.462E+6 64.8%
40388 717.444E+3 2.040E+6 64.8%
40503 517.818E+3 1.472E+6 64.8%
Empirical Average Total 725.630E+3 29.025E+6
Average Annual Change 100.52%
Model Average Total 1,152,521 46,100,851
Average Annual Change 102.38%
Average Model Reliance 37.04%
5.3.2 Las Animas County
Table 9 Total produced water generated in gallons per well in Las Animas County
Well API Total, Total, Model
Empirical Model Reliance
08280 8,305,080 8,305,080 0.0%
08908 12,221,244 13,334,379 8.3%
09386 51,169,650 51,391,546 0.4%
09490 50,002,386 52,106,716 4.0%
09782 17,527,440 17,527,440 0.0%
09871 5,439,588 12,173,292 55.3%
09874 5,173,140 13,870,217 62.7%
09878 1,281,042 2,315,005 44.7%
09885 567,336 786,336 27.9%
09898 34,202,700 75,383,558 54.6%
Empirical Average Total 18,588,961 185,889,606
Average Annual Change 107.9%
Model Average Total 24,719,357 247,193,569
Average Annual Change 102.3%
Average Model Reliance 24.80%
Coal-bed methane wells produced only natural gas, but output 44.4% more energy than
regular oil and gas wells. This could be due to any number of factors: CBM wells in our study relied


29
on the model more than oil and gas wells possibly skewing CBM wells to a higher output; technical difficulties in capturing both oil and gas versus just capturing gas; or the shallower depth in CBM wells might reduce the amount of gas lost as it comes to the surface. Regardless of the reason, the relatively significant difference will have implications when assessing their comparative environmental impacts. Since energy output in MJ's is the functional unit, the larger output in CBM wells will reduced the overall impact generated by their chemicals.


30
6 Results and Discussion
The result depicted were for our specific case, but the most influential aspect of the environmental impact resulted from the large variability the flowback fractions for each well. This fraction was responsible for governing the range of environmental impacts. The flowback fraction was highly variable even between similar wells sharing a geological formation, and values were left up to low resolution data or only one data point and assumptions. Shale flowback fraction was accurate only for the entire Niobrara shale as a whole, not each well, and CBM wells had only one value to use.
The flowback fraction is functionally proportional to environmental impact, so a doubling in flowback would double the environmental impact. The differences in flowback fraction 17.5% for shale and 61% for CBM was deemed to be largely responsible for the environmental impact from CBM being 12.6% larger than shale. Our hypothesis going in to this research was the other way around, with shale having a larger impact than CBM. If the flowback fractions were the same for shale and CBM than shale would indeed have a larger impact. Increasing the flowback fraction for shale to 19.7% or reducing it to 54.2% for CBM, while leaving the other flowback value constant would equate the two impacts. Both of these values are within the possible ranges of values, telling us that the shale and CBM are similar in terms of environmental impact for chemicals relative to the functional output. An assessment on the environmental impact of the other phases of the life cycle are needed to determine the overall impacts for the entire operation.
6.1 Energy and produced water comparison
The literature states that coal-bed methane wells will generate much higher quantities of produced water compared to regular oil and gas wells employing hydraulic fracturing37. Once the average energy and produced water output per well for Weld County and Las Animas were


31
calculated, produced water was divided by the functional unit (energy in MJ's) yielding the average produced water (gallons) per unit energy (MJ).
Weld County averaged 1,152,521 and Las Animas averaged 24,719,357 gallons per well of produced water, a ratio of 21.5 times more produced water was generated for CBM wells than regular oil and gas wells. Weld County wells generated an average of 1,034,841,937 MJ of energy; Las Animas wells generated 1,493,937,492, a ratio of 1.44 greater. These findings were on par with the literature Weld County has a rate of 0.0011 gal/MJ compared to 0.0165 gal/MJ for Las Animas. Las Animas generates 14.9 times more produced water for the same energy output.
6.2 Categorization factors
Of the 184 chemicals detected and analyzed, categorization factors (CFs) were generated for 128, with the remaining 56 chemicals having no factors generated. These 56 chemicals included the subset of 33 chemicals that had no CAS number, were ambiguously-named, had generic names, were proprietary, or were just identified by their category (i.e. surfactant), so we knew we would not be able to generate any reliable CF's anyway. There were 36 inorganics chemicals, as well, for which USEtox is not specifically designed. For inorganic compounds, many chemical properties are assumed to be a specific value Henry's constant (kH), vapor pressure (pv), the degradation rates in air, water, sediment, and soil are all 1 X 10-20. Many of the properties used within USEtox have equations that can be further used to estimate other properties. Once these equations are applied most of the required properties are known; the only exception is the octanol-water coefficient, which is the main physio-chemical property used to estimate most other properties. Inorganic compounds relied heavily on experimental data because EPI Suite cannot be applied to inorganic compounds with any accuracy. USEtox requires a certain set of chemical properties to generate the CF's, which is detailed in Section 2.2.1 Physio-chemical properties required for USEtox, so if any one of these chemicals property data is missing no factors are able to be created. The remaining 23


32
chemicals for which we could not generate CF's were only missing one or two pieces of data, so with relatively few additions to the data CF's should be able to be generated for these 56 chemicals. In most cases the octanol-water (Kow) or vapor pressure were missing since they are fundamental properties and cannot be calculated or estimated within USEtox. If their empirical values could not be found or predicted via modeling software than there were relatively few options to finding a viable value. CF's were generated using the North American landscape, with a OECD countries average household indoor environment with Industry, OECD as the industrial indoor environment. Table 10 shows all the categorization factors for every chemical assessed.


33
Table 10 Raw categorization factors for ecotoxicity
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil
Average of all known chemicals 1.98E+04 2.21E+04 2.36E+04 1.61E+04 6.08E+05 2.09E+02 4.30E+03 4.30E+03
3rd Party Additive n/a n/a n/a n/a n/a n/a n/a n/a
l-(benzyl)quinolinium chloride 15619-48-4 4.41E-02 4.41E-02 4.41E-02 4.41E-02 1.30E-01 3.12E-10 6.52E-02 6.52E-02
1,2,3-trimethylbenzene 526-73-8 4.02E+02 4.26E+02 4.42E+02 3.62E+02 7.03E+03 1.47E+02 3.29E+02 3.29E+02
1,2,4-trimethylbenzene 95-63-6 5.03E+01 5.33E+01 5.53E+01 4.54E+01 8.73E+02 1.83E+01 4.16E+01 4.16E+01
2,2-dibromo-3-nitrilopropionamide 10222-01-2 5.08E+03 5.09E+03 5.10E+03 5.07E+03 1.71E+04 5.31E-02 7.43E+03 7.43E+03
2,3-Dihydroxypropyl-trimethylammonium chloride 34004-36-0 6.47E-03 6.48E-03 6.49E-03 6.45E-03 2.22E-02 1.85E-16 9.33E-03 9.33E-03
2-amine-2-methyl-propanol 124-68-5 1.43E+00 1.60E+00 1.71E+00 1.16E+00 4.48E+01 7.91E-06 2.16E-01 2.16E-01
2-bromo-3-nitrilopropionamide 1113-55-9 6.19E-01 6.20E-01 6.21E-01 6.16E-01 2.21E+00 2.28E-09 9.00E-01 9.00E-01
2-butoxyethanol 111-76-2 8.48E-01 8.57E-01 8.63E-01 8.32E-01 4.81E+00 1.69E-06 1.14E+00 1.14E+00
2-ethylhexanol 104-76-7 2.82E+01 2.89E+01 2.93E+01 2.71E+01 2.50E+02 9.96E-01 3.48E+01 3.48E+01
3,4,4-trimethyloxazolidine 75673-43-7 2.94E+02 2.95E+02 2.96E+02 2.93E+02 1.09E+03 4.82E+00 4.34E+02 4.34E+02
3-chloro-2-hydroxypropyl- trimethylazanium;chloride 3327-22-8 1.15E+02 1.15E+02 1.15E+02 1.15E+02 3.95E+02 3.06E-11 1.66E+02 1.66E+02
4,4-dimethyloxazolidine 51200-87-4 5.24E+00 5.86E+00 6.26E+00 4.22E+00 1.65E+02 8.41E-03 7.39E-01 8.43E-01
4-nonylphenyl 127087-87-0 4.07E+04 4.21E+04 4.30E+04 3.84E+04 4.59E+05 3.24E-06 4.54E+04 4.54E+04
Acetic acid 64-19-7 9.91E-01 1.09E+00 1.15E+00 8.27E-01 2.68E+01 2.53E-05 3.37E-01 3.37E-01
Acetic anhydride 108-24-7 6.57E+00 6.60E+00 6.62E+00 6.53E+00 2.64E+01 1.18E-01 9.54E+00 9.54E+00
Alcohol amine 2.28E+00 2.29E+00 2.29E+00 2.27E+00 8.07E+00 4.88E-09 3.28E+00 3.28E+00
Aldehyde 2.79E+02 2.80E+02 2.81E+02 2.77E+02 1.07E+03 4.81E-06 3.98E+02 3.98E+02
Alkoxylated amine 1.25E+06 1.41E+06 1.52E+06 9.72E+05 4.35E+07 7.01E-05 8.72E+03 8.72E+03
Alkyl amine surfactant n/a n/a n/a n/a n/a n/a n/a n/a
Alkyl dimethyl benzyl ammonium chloride 68424-85-1 1.01E+02 1.09E+02 1.14E+02 8.80E+01 2.19E+03 6.18E-06 6.22E+01 6.22E+01
Alkyl pyridine benzyl quaternary ammonium chloride 68909-18-2 5.73E-02 5.73E-02 5.73E-02 5.73E-02 1.71E-01 1.39E-10 8.46E-02 8.46E-02


34
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Alkylene oxide block polymer n/a n/a n/a n/a n/a n/a n/a n/a
Aluminum oxide 1344-28-1 n/a n/a n/a n/a n/a n/a n/a n/a
Amide 1.11E+02 1.22E+02 1.29E+02 9.38E+01 2.88E+03 2.04E-02 4.48E+01 4.48E+01
Amine salts n/a n/a n/a n/a n/a n/a n/a n/a
Amines, coco alkyl, ethoxylated 61791-14-8 1.34E+03 1.37E+03 1.40E+03 1.27E+03 1.30E+04 2.94E-09 1.55E+03 1.55E+03
Amines, tallow alkyl, ethoxylated 61791-26-2 1.27E+02 1.41E+02 1.51E+02 1.02E+02 3.93E+03 1.28E-09 2.01E+01 2.01E+01
Ammonium acetate 631-61-8 5.34E+01 5.35E+01 5.36E+01 5.32E+01 1.89E+02 2.57E-06 7.68E+01 7.68E+01
Ammonium chloride 12125-02-9 3.03E+03 3.03E+03 3.02E+03 3.03E+03 8.33E+03 8.09E-12 4.80E+03 4.80E+03
Ammonium dihydrogen phosphate 7722-76-1 n/a n/a n/a n/a n/a n/a n/a n/a
Ammonium hydroxide 1336-21-6 n/a n/a n/a n/a n/a n/a n/a n/a
Ammonium persulfate 7727-54-0 4.80E+02 4.80E+02 4.79E+02 4.81E+02 1.32E+03 7.88E-13 7.61E+02 7.61E+02
Ammonium phosphite 13446-12-3 1.07E+02 1.07E+02 1.07E+02 1.08E+02 2.96E+02 2.36E-13 1.70E+02 1.70E+02
Ammonium salt n/a n/a n/a n/a n/a n/a n/a n/a
Amphoteric surfacta nt n/a n/a n/a n/a n/a n/a n/a n/a
Antifoam n/a n/a n/a n/a n/a n/a n/a n/a
Apatite 64476-38-6 n/a n/a n/a n/a n/a n/a n/a n/a
Aromatic aldehyde 5.17E+01 5.27E+01 5.34E+01 4.99E+01 4.10E+02 3.28E+00 6.65E+01 6.65E+01
Bentonite, benzyl(hydrogenated tallow alkyl) dimethylammonium stearate complex 121888-68-4 n/a n/a n/a n/a n/a n/a n/a n/a
Biotite 1302-27-8 n/a n/a n/a n/a n/a n/a n/a n/a
Borate 7550-67-7 n/a n/a n/a n/a n/a n/a n/a n/a
Calcite 471-34-1 n/a n/a n/a n/a n/a n/a n/a n/a
Calcium chloride 10043-52-4 n/a n/a n/a n/a n/a n/a n/a n/a
Carboxymethyl guar gum, sodium salt 39346-76-4 n/a n/a n/a n/a n/a n/a n/a n/a
Chlorous acid, sodium salt 7758-19-2 1.00E-01 1.00E-01 1.00E-01 1.00E-01 2.76E-01 2.15E-16 1.59E-01 1.59E-01
Choline chloride 67-48-1 1.32E+00 1.34E+00 1.35E+00 1.29E+00 8.36E+00 3.61E-13 1.73E+00 1.73E+00


35
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Cinnamaldehyde 104-55-2 5.47E+02 5.57E+02 5.63E+02 5.30E+02 4.06E+03 5.60E+00 7.03E+02 7.03E+02
Citric acid 77-92-9 1.64E+00 1.67E+00 1.69E+00 1.59E+00 1.17E+01 1.97E-13 2.09E+00 2.09E+00
Clay n/a n/a n/a n/a n/a n/a n/a n/a
Cobalt acetate 71-48-7 n/a n/a n/a n/a n/a n/a n/a n/a
Crystalline silica, quartz 14808-60-7 n/a n/a n/a n/a n/a n/a n/a n/a
Dibromoacetonitrile 3252-43-5 1.13E+01 1.14E+01 1.15E+01 1.12E+01 5.50E+01 9.65E-04 1.57E+01 1.57E+01
Didecyl dimethyl ammonium chloride 111-42-2 4.77E+00 5.24E+00 5.55E+00 4.00E+00 1.28E+02 2.77E-04 1.70E+00 1.70E+00
Diethylenetriamine 111-40-0 3.40E+00 3.58E+00 3.70E+00 3.09E+00 5.49E+01 5.87E-13 2.92E+00 2.92E+00
Dinonyphenyl 9014-93-1 n/a n/a n/a n/a n/a n/a n/a n/a
Disodium ethylene diaminediacetate 38011-25-5 8.02E-06 8.06E-06 8.08E-06 7.95E-06 3.37E-05 1.38E-18 1.13E-05 1.13E-05
EDTA/copper chelate 14025-15-1 2.75E+00 2.77E+00 2.78E+00 2.71E+00 1.37E+01 2.41E-22 3.78E+00 3.78E+00
Enzyme n/a n/a n/a n/a n/a n/a n/a n/a
EO-C7-9-iso, C8 rich-alcohols 78330-19-5 3.36E+02 3.36E+02 3.37E+02 3.36E+02 1.08E+03 3.18E-08 4.94E+02 4.94E+02
EO-C9-ll-iso, CIO-rich alcohols 78330-20-8 1.57E+01 1.71E+01 1.81E+01 1.33E+01 3.96E+02 2.78E+00 7.32E+00 7.32E+00
Ethanol 64-17-5 4.09E-01 4.12E-01 4.14E-01 4.04E-01 1.97E+00 4.98E-03 5.75E-01 5.75E-01
Ethoxylated alcohol 2.35E+02 2.36E+02 2.37E+02 2.33E+02 9.88E+02 9.45E-09 3.32E+02 3.32E+02
Ethoxylated amine 1.27E+02 1.41E+02 1.51E+02 1.02E+02 3.93E+03 1.28E-09 2.01E+01 2.01E+01
Ethoxylated branched C13 alcohol 78330-21-9 1.22E+02 1.33E+02 1.41E+02 1.02E+02 3.22E+03 1.87E+01 4.90E+01 4.90E+01
Ethoxylated decyl alcohol 2.61E+01 2.84E+01 2.99E+01 2.23E+01 6.35E+02 9.06E-10 1.23E+01 1.23E+01
Ethoxylated fatty acid 1.27E+02 1.41E+02 1.51E+02 1.02E+02 3.93E+03 1.28E-09 2.01E+01 2.01E+01
Ethylene glycol 107-21-1 1.84E-01 1.85E-01 1.85E-01 1.83E-01 7.44E-01 2.62E-05 2.60E-01 2.60E-01
Fatty acid tall oil amide 1.49E+04 1.67E+04 1.80E+04 1.18E+04 4.96E+05 2.46E+02 6.08E+02 6.08E+02
Fatty acids n/a n/a n/a n/a n/a n/a n/a n/a
Fatty acids, tall oil 61790-12-3 1.49E+04 1.67E+04 1.80E+04 1.18E+04 4.96E+05 2.46E+02 6.08E+02 6.08E+02
Formaldehyde amine resin 56652-26-7 1.34E+01 1.40E+01 1.45E+01 1.24E+01 1.93E+02 1.43E-03 1.26E+01 1.26E+01


36
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Formaldehyde;2- methyloxirane;(lE,3E)-4,5,5- trimethylhexa-l,3-dien-l-ol 29316-47-0 4.40E+02 4.48E+02 4.54E+02 4.27E+02 3.26E+03 4.46E-01 5.67E+02 5.67E+02
Formaldehyde;2-methyloxirane;4- nonylphenol;oxirane 63428-92-2 n/a n/a n/a n/a n/a n/a n/a n/a
Formic acid 64-18-6 9.12E-01 1.00E+00 1.06E+00 7.66E-01 2.40E+01 4.83E-06 3.44E-01 3.44E-01
Glutaraldehyde 111-30-8 2.06E+02 2.10E+02 2.13E+02 1.99E+02 1.63E+03 3.22E-01 2.57E+02 2.57E+02
Glycerine 56-81-5 2.71E-02 2.72E-02 2.73E-02 2.69E-02 1.14E-01 9.76E-07 3.81E-02 3.81E-02
Goethite 1310-14-1 n/a n/a n/a n/a n/a n/a n/a n/a
Guargum 9000-30-0 3.67E+03 3.67E+03 3.67E+03 3.68E+03 1.04E+04 5.74E-35 5.50E+03 5.50E+03
Guargum derivative 7.61E+00 7.60E+00 7.60E+00 7.62E+00 2.17E+01 7.37E-13 1.14E+01 1.14E+01
Haloalkyl heteropolycycle salt n/a n/a n/a n/a n/a n/a n/a n/a
Heavy aliphatic petroleum naphtha solvent 64742-96-7 1.40E+00 1.52E+00 1.61E+00 1.19E+00 3.45E+01 9.48E-02 7.08E-01 7.08E-01
Heavy aromatic petroleum naphtha 64742-94-5 3.09E+01 3.28E+01 3.41E+01 2.76E+01 5.70E+02 9.98E+00 2.39E+01 2.39E+01
Heavy hydrotreated petroleum naphtha 64742-48-9 1.26E+02 1.36E+02 1.43E+02 1.09E+02 2.80E+03 1.50E+01 7.80E+01 7.80E+01
Hexamethylenetetramine 100-97-0 1.69E-01 1.70E-01 1.70E-01 1.67E-01 7.22E-01 1.36E-07 2.43E-01 2.43E-01
Hydrated magnesium silicate (talc) 14807-96-6 n/a n/a n/a n/a n/a n/a n/a n/a
Hydrochloric acid 7641-01-0 2.83E+04 2.82E+04 2.82E+04 2.83E+04 7.78E+04 6.34E-11 4.48E+04 4.48E+04
Hydrotreated light petroleum distillate 64742-47-8 3.80E+02 4.10E+02 4.31E+02 3.29E+02 8.59E+03 3.84E+01 2.29E+02 2.29E+02
Hydrotreated medium petroleum distillates 64742-46-7 1.13E+06 1.25E+06 1.33E+06 9.23E+05 3.31E+07 2.19E+04 3.22E+05 3.22E+05
Inorganic base n/a n/a n/a n/a n/a n/a n/a n/a
Inorganic salt 3.99E+03 3.99E+03 3.99E+03 4.00E+03 1.10E+04 1.03E-11 6.33E+03 6.33E+03
Isopropanol 67-63-0 4.99E-02 5.26E-02 5.44E-02 4.55E-02 7.93E-01 1.19E-02 4.59E-02 4.59E-02
Isotridecanol, ethoxylated (TDA-6) 9043-30-5 4.45E+01 4.53E+01 4.58E+01 4.31E+01 3.26E+02 1.58E-08 5.73E+01 5.73E+01
Lactic acid 50-21-5 2.43E-03 2.49E-03 2.52E-03 2.34E-03 2.07E-02 2.98E-10 2.94E-03 2.94E-03
Laury alcohol ethoxylate 68551-12-2 8.74E+02 9.64E+02 1.02E+03 7.24E+02 2.45E+04 1.39E+02 2.88E+02 2.88E+02


37
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Light aromatic petroleum naphtha solvent 64742-95-6 3.97E+01 4.22E+01 4.39E+01 3.55E+01 7.32E+02 1.28E+01 3.07E+01 3.07E+01
Magnesium oxide 1309-48-4 n/a n/a n/a n/a n/a n/a n/a n/a
Magnesium peroxide 14452-57-4 n/a n/a n/a n/a n/a n/a n/a n/a
Mesitylene 108-67-8 2.15E+01 2.28E+01 2.36E+01 1.95E+01 3.64E+02 7.86E+00 1.83E+01 1.83E+01
Methanol 67-56-1 3.31E-01 3.34E-01 3.36E-01 3.27E-01 1.67E+00 4.15E-03 4.63E-01 4.63E-01
Methyl isobutyl ketone 108-10-1 4.83E-01 5.03E-01 5.17E-01 4.48E-01 6.51E+00 7.08E-02 4.95E-01 4.95E-01
Naphthalene 91-20-3 2.07E+01 2.30E+01 2.46E+01 1.67E+01 6.39E+02 8.47E-01 3.77E+00 3.77E+00
Naphthenic acid ethoxylate 68410-62-8 6.36E+01 6.37E+01 6.38E+01 6.35E+01 2.12E+02 1.63E-08 9.39E+01 9.39E+01
N-dimethyl formamide 68-12-2 4.89E-01 4.90E-01 4.91E-01 4.87E-01 1.77E+00 1.38E-04 7.03E-01 7.03E-01
Nitrilotriacetate, trisodium salt (NTA) 5064-31-3 1.23E-02 1.24E-02 1.24E-02 1.22E-02 5.59E-02 5.85E-18 1.71E-02 1.71E-02
Nitrogen 7727-37-9 4.87E+01 4.90E+01 4.91E+01 4.83E+01 2.03E+02 2.55E-20 6.88E+01 6.88E+01
No hazardous ingredients n/a n/a n/a n/a n/a n/a n/a n/a
No MSDS ingredients (Friction Reducer) n/a n/a n/a n/a n/a n/a n/a n/a
Nonhazardous n/a n/a n/a n/a n/a n/a n/a n/a
Non-ionic surfactant n/a n/a n/a n/a n/a n/a n/a n/a
N-propanol zirconate n/a n/a n/a n/a n/a n/a n/a n/a
N-propyl zirconate 23519-77-9 n/a n/a n/a n/a n/a n/a n/a n/a
Olefin 64743-02-8 3.26E+02 3.56E+02 3.77E+02 2.74E+02 8.46E+03 5.14E+01 1.42E+02 1.42E+02
Organic polyol n/a n/a n/a n/a n/a n/a n/a n/a
Organic sulfonic acid 27176-87-0 1.57E+02 1.63E+02 1.67E+02 1.47E+02 1.97E+03 1.50E-04 1.61E+02 1.61E+02
Organic sulfur compound n/a n/a n/a n/a n/a n/a n/a n/a
Oxirane, 2-methyl-, polymer with oxirane, monodecyl ether 37251-67-5 4.21E+02 4.47E+02 4.64E+02 3.78E+02 7.57E+03 1.06E-02 3.26E+02 3.26E+02
Oxyalkylated fatty acid n/a n/a n/a n/a n/a n/a n/a n/a
Phenol/formaldehyde resin 9003-35-4 1.34E+01 1.40E+01 1.45E+01 1.24E+01 1.93E+02 1.43E-03 1.26E+01 1.26E+01


38
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Poly( oxy-l,2-ethanediyl),.alpha.-tetradecyl-.omega.-hydroxy 27306-79-2 4.50E+03 5.11E+03 5.51E+03 3.50E+03 1.61E+05 1.15E+01 1.13E+01 1.13E+01
Poly(tetrafluoroethylene) 9002-84-0 3.67E-01 3.87E-01 4.00E-01 3.34E-01 5.95E+00 7.95E-02 3.32E-01 3.32E-01
Polyacrylate 79-10-7 4.96E-01 4.99E-01 5.02E-01 4.89E-01 2.43E+00 4.15E-04 6.85E-01 6.85E-01
Polyether n/a n/a n/a n/a n/a n/a n/a n/a
Polyethylene glycol 25322-68-3 2.11E+02 2.12E+02 2.12E+02 2.10E+02 7.26E+02 4.18E-09 3.04E+02 3.04E+02
Polyoxyalkylenes 68951-67-7 1.90E+03 2.10E+03 2.24E+03 1.55E+03 5.59E+04 1.97E+02 4.73E+02 4.73E+02
Polyoxyalkylenes surfactant n/a n/a n/a n/a n/a n/a n/a n/a
Polyquaternary amine n/a n/a n/a n/a n/a n/a n/a n/a
Polysaccharide 68130-15-4 2.07E-05 2.11E-05 2.14E-05 2.00E-05 1.62E-04 1.32E-32 2.56E-05 2.56E-05
Potassium carbonate 584-08-7 1.15E-02 1.15E-02 1.15E-02 1.15E-02 3.95E-02 1.08E-22 1.66E-02 1.66E-02
Potassium hydroxide 1310-58-3 7.61E-03 7.60E-03 7.60E-03 7.62E-03 2.09E-02 1.99E-17 1.21E-02 1.21E-02
Potassium persulfate 7727-21-1 1.45E+00 1.45E+00 1.45E+00 1.45E+00 3.99E+00 2.25E-15 2.30E+00 2.30E+00
Propanol 71-23-8 3.09E-01 3.14E-01 3.18E-01 3.00E-01 2.25E+00 8.14E-03 4.04E-01 4.04E-01
Propargyl alcohol 107-19-7 5.21E+02 5.25E+02 5.29E+02 5.13E+02 2.73E+03 2.43E+00 7.19E+02 7.19E+02
Proprietary component, biocide n/a n/a n/a n/a n/a n/a n/a n/a
Proprietary component, surfactant n/a n/a n/a n/a n/a n/a n/a n/a
Proprietary sesquiolate 8007-43-0 2.79E-02 2.75E-02 2.73E-02 2.84E-02 1.58E-03 2.07E-16 5.72E-08 5.72E-08
Propylene glycol 57-55-6 1.11E-01 1.11E-01 1.12E-01 1.10E-01 4.95E-01 3.21E-06 1.54E-01 1.54E-01
Quaternary amine n/a n/a n/a n/a n/a n/a n/a n/a
Quaternary ammonium compound 122-18-9 4.20E+02 4.66E+02 4.96E+02 3.44E+02 1.24E+04 4.12E-05 1.06E+02 1.06E+02
Quaternary ammonium compounds, bis(hydrogenated tallow alkyl)dimethyl, salts with montmorillonite 68911-87-5 n/a n/a n/a n/a n/a n/a n/a n/a
Quaternary ammonium compounds, bis(hydrotreated tallow alkyl)dimethyl, salts with bentonite 68953-58-2 n/a n/a n/a n/a n/a n/a n/a n/a
Quaternary ammonium salt 4.20E+02 4.66E+02 4.96E+02 3.44E+02 1.24E+04 4.12E-05 1.06E+02 1.06E+02


39
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Flousehold To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Silica, amorphous fumed 7631-86-9 1.59E+02 1.59E+02 1.59E+02 1.59E+02 4.37E+02 4.07E-13 2.52E+02 2.52E+02
Sodium bicarbonate 144-55-8 2.68E-02 2.68E-02 2.68E-02 2.67E-02 9.27E-02 5.54E-07 3.85E-02 3.88E-02
Sodium bromide 7647-15-6 1.45E+02 1.45E+02 1.45E+02 1.45E+02 3.99E+02 3.10E-13 2.30E+02 2.30E+02
Sodium chloride 7647-14-5 3.99E+03 3.99E+03 3.99E+03 4.00E+03 1.10E+04 1.03E-11 6.33E+03 6.33E+03
Sodium erythorbate 6381-77-7 1.27E+00 1.43E+00 1.54E+00 9.93E-01 4.40E+01 1.53E-21 5.88E-03 5.88E-03
Sodium hydroxide 1310-73-2 3.10E+04 3.10E+04 3.09E+04 3.10E+04 8.53E+04 9.09E-11 4.91E+04 4.91E+04
Sodium hydroxyacetate 2836-32-0 7.49E-03 7.65E-03 7.76E-03 7.22E-03 6.12E-02 2.12E-08 9.19E-03 9.19E-03
Sodium hypochlorite 7681-52-9 1.03E+01 1.03E+01 1.02E+01 1.03E+01 2.82E+01 2.30E-14 1.63E+01 1.63E+01
Sodium iodide 7681-82-5 1.63E+02 1.63E+02 1.62E+02 1.63E+02 4.48E+02 3.07E-13 2.58E+02 2.58E+02
Sodium lactate 72-17-3 5.94E-02 5.97E-02 6.00E-02 5.89E-02 2.55E-01 1.31E-05 8.35E-02 8.35E-02
Sodium perborate tetrahydrate 10486-00-7 n/a n/a n/a n/a n/a n/a n/a n/a
Sodium persulfate 7775-27-1 3.10E+00 3.10E+00 3.09E+00 3.11E+00 8.53E+00 5.02E-15 4.91E+00 4.91E+00
Sodium sulfate 7757-82-6 3.73E+00 3.72E+00 3.72E+00 3.73E+00 1.03E+01 7.12E-15 5.90E+00 5.90E+00
Sodium;prop-2-enamide;prop-2-enoate;prop-2-enoic acid 62649-23-4 3.31E+03 3.32E+03 3.32E+03 3.29E+03 1.19E+04 5.03E-06 4.75E+03 4.75E+03
Sorbitan monooleate polyoxyethylene derivative 9005-65-6 1.82E+04 1.82E+04 1.82E+04 1.83E+04 5.02E+04 2.25E-31 2.80E+04 2.80E+04
Sorbitan, mono-9-octadecenoate, (Z) 1338-43-8 3.56E+03 3.95E+03 4.22E+03 2.91E+03 1.06E+05 8.31E-06 7.79E+02 7.79E+02
Soybean oil methyl ester 67784-80-9 4.18E+04 4.67E+04 4.99E+04 3.36E+04 1.31E+06 4.46E+03 6.54E+03 6.54E+03
Styrene acrylic copolymer 25085-34-1 6.10E+00 6.28E+00 6.40E+00 5.80E+00 6.26E+01 2.72E-04 6.93E+00 6.93E+00
Sucrose 57-50-1 1.33E-02 1.33E-02 1.34E-02 1.32E-02 5.36E-02 1.35E-21 1.87E-02 1.87E-02
Surfactants 4.99E-02 5.26E-02 5.44E-02 4.55E-02 7.93E-01 1.19E-02 4.59E-02 4.59E-02
Tall oil acid diethanolamide 68155-20-4 3.04E+03 3.37E+03 3.59E+03 2.49E+03 8.92E+04 5.62E-05 7.19E+02 7.19E+02
Terpenes and terpenoids 68956-56-9 3.38E-01 3.71E-01 3.93E-01 2.83E-01 9.03E+00 2.25E-13 1.23E-01 1.23E-01
Terpenes and terpenoids, sweet orange-oil 68647-72-3 2.34E+02 2.50E+02 2.61E+02 2.06E+02 4.74E+03 4.60E+01 1.65E+02 1.65E+02
Tert-butyl hydroperoxide 75-91-2 3.83E+01 3.97E+01 4.06E+01 3.59E+01 4.57E+02 1.66E+00 4.19E+01 4.19E+01


40
Endpoint Ecotoxicity Characterization Factors [PDF.m3.day/kgemitted] (freshwater)
Chemical CAS Number To Household To Industrial To Urban Continental To Fresh To Sea To Natural To Agricultural
Air Air Air Rural Air Water Water Soil Soil
Tetramethyl ammonium chloride 75-57-0 5.31E+00 5.34E+00 5.36E+00 5.26E+00 2.29E+01 3.07E-11 7.46E+00 7.46E+00
Tetrasodium ethylenediamine tetraacetate 64-02-8 n/a n/a n/a n/a n/a n/a n/a n/a
Thiourea polymer 68527-49-1 5.79E-01 5.79E-01 5.79E-01 5.79E-01 1.71E+00 4.29E-08 8.56E-01 8.56E-01
Trade secret n/a n/a n/a n/a n/a n/a n/a n/a
Triethanolamine 102-71-6 3.30E-01 3.59E-01 3.78E-01 2.83E-01 7.92E+00 3.31E-10 1.61E-01 1.79E-01
Triethanolamine zirconate 101033-44-7 n/a n/a n/a n/a n/a n/a n/a n/a
Triethylene glycol 112-27-6 6.16E-02 6.18E-02 6.19E-02 6.14E-02 2.18E-01 4.83E-08 8.87E-02 8.87E-02
Triisopropanolamine 122-20-3 1.68E+00 1.81E+00 1.89E+00 1.47E+00 3.57E+01 1.21E-08 1.04E+00 1.14E+00
Trimethylamine 75-50-3 6.62E-01 8.13E-01 9.14E-01 4.10E-01 4.11E+01 1.83E-03 3.65E-02 3.66E-02
Trisodium ethylenediaminetriacetate 19019-43-3 3.42E-02 3.44E-02 3.45E-02 3.39E-02 1.44E-01 1.73E-18 4.80E-02 4.80E-02
Various oxides and trace elements (Fe203, CaO, and MgO) are the largest fractions n/a n/a n/a n/a n/a n/a n/a n/a
Vinylidene chloride-methyl acrylate copolymer 25038-72-6 1.53E+02 1.57E+02 1.60E+02 1.46E+02 1.46E+03 2.91E+01 1.85E+02 1.85E+02
Water 7732-18-5 n/a n/a n/a n/a n/a n/a n/a n/a
Xylene 1330-20-7 1.82E+01 1.95E+01 2.03E+01 1.62E+01 3.50E+02 3.78E+00 1.38E+01 1.38E+01
Zirconium complex n/a n/a n/a n/a n/a n/a n/a n/a
Zirconium sodium hydroxy lactate complex 113184-20-6 n/a n/a n/a n/a n/a n/a n/a n/a
Zirconium solution n/a n/a n/a n/a n/a n/a n/a n/a
Zirconium, acetate lactate oxo ammonium complexes 68909-34-2 1.58E-02 1.58E-02 1.58E-02 1.58E-02 4.66E-02 7.14E-14 2.34E-02 2.34E-02


41
The yellow and green colors in Table 10 match the chemicals that are not in either USEtox or TRACI as mentioned in Section 2.1 Procedure for generating chemical categorization factors by data availability: yellow coincides to chemicals that are completely unknown with categorization factors that could not be generated; green references chemicals that had a viable substitute chemical or the same chemical found under a similar name but could not be confirmed to be the same chemical, although it was highly likely.
6.3 Environmental impact assessment
Since our assessment focused only on the chemical mass that evaporated into the air and the mass that remained within the disposal pit water, we required only the emissions to continental rural air and to fresh water. In order to calculate the impact, the categorization factors were applied to the evaporative mass and mass the remains in the disposal pit yielding PDF.m3.day (potentially disappeared fraction of species integrated over the freshwater volume and the duration of one day38). After finding the final impact per chemical for each county the average energy output was divided to determine the impact per unit of energy delivered for each county.
For the chemicals lacking categorization factors we took the average CF for the known chemicals and applied it to the unknown chemicals. This methodology was required for 56 of the 184 chemicals, representing 30.4% of all chemicals.
Chemicals without a flowback mass, not detected in their specific county, or combined with substitute chemicals were omitted from the following tables, since they had no impact. Any impacts for omitted chemicals were accountable in their respective alternative chemicals. Additionally, water and sand were removed from the impact assessment because they were the vast majority of mass for the fracking fluid, but had no impact and are inert. The models were unable to discern
water and sand and would calculated an impact, skewing the results.


42
Table 11 Environmental impact for Las Animas County by chemical
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
l-(benzyl)quinolinium chloride 15619-48-4 38.9 0.05 38.81 2.3E-3 1.7E+0 55.8E-15 41.4E-12 1.0E-12
1,2,3-trimethyl benzene 526-73-8 5.2 5.22 0.00 1.9E+3 000.0E+0 45.6E-9 000.0E+0 1.1E-9
1,2,4-trimethyl benzene 95-63-6 1,511.4 1,511.40 0.00 68.6E+3 000.0E+0 1.7E-6 000.0E+0 41.4E-9
2,2~dibromo~3~ nitrilopropionamide 10222-01-2 982.7 653.38 329.33 3.3E+6 1.7E+6 80.0E-6 40.3 E-6 3.0E-6
2,3-Dihydroxypropyl-trimethyl ammonium chloride 34004-36-0 19.1 0.00 19.09 12.4E-9 123.2E-3 298.5E-21 3.0E-12 74.4E-15
2-amine-2-methyl-propanol 124-68-5 8.7 8.71 0.00 10.1E+0 000.0E+0 243.3E-12 000.0E+0 6.1E-12
2~bromo~3~ nitrilopropionamide 1113-55-9 1.5 0.90 0.57 553.4E-3 351.3E-3 13.4E-12 8.5E-12 546.4E-15
2-ethyl hexanol 104-76-7 11.9 11.88 0.00 321.4E+0 000.0E+0 7.8E-9 000.0E+0 194. IE-12
3,4,4-trimethyloxazolidine 75673-43-7 43.9 43.94 0.00 12.9E+3 000.0E+0 311.0E-9 000.0E+0 7.8E-9
3-chloro-2-hydroxypropyl-trimethylazanium;ch bride 3327-22-8 3.8 0.00 3.82 2.0E-3 437.9E+0 47.4E-15 10.6E-9 264.5E-12
3rd Party Additive 462.5
4,4-dimethyloxazolidine 51200-87-4 881.5 881.45 0.00 3.7E+3 000.0E+0 89.8E-9 000.0E+0 2.2E-9
4-nonylphenyl 127087-87-0 4.1 0.00 4.14 1.0E-3 159.0E+3 24.2E-15 3.8E-6 96.0E-9
Acetic acid 64-19-7 15,784.9 15,784.94 0.00 13.1E+3 000.0E+0 315.4E-9 000.0E+0 7.9E-9
Acetic anhydride 108-24-7 5.1 5.12 0.00 33.4E+0 000.0E+0 806.8E-12 000.0E+0 20.2E-12
Aldehyde 115.9 115.92 0.00 32.1E+3 000.0E+0 776.6E-9 000.0E+0 19.4E-9
Alkyl dimethyl benzyl ammonium chloride 68424-85-1 197.6 0.00 197.56 313.1E-6 17.4E+3 7.6E-15 419.8E-9 10.5E-9
Alkyl pyridine benzyl quaternary ammonium chloride 68909-18-2 35.5 0.00 35.48 2.5E-6 2.0E+0 60.6E-18 49.1E-12 1.2E-12
Alkylene oxide block polymer 471.7
Aluminum oxide 1344-28-1 574.4 0.00 574.43
Amine salts 21.7
Amines, coco alkyl, ethoxylated 61791-14-8 1.7 0.00 1.74 452.0E-6 2.2E+3 10.9E-15 53.4E-9 1.3E-9


43
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Amines, tallow alkyl, ethoxylated 61791-26-2 9,920.5 0.00 9,920.48 34.4E-9 1.0E+6 832.0E-21 24.5E-6 613.0E-9
Ammonium acetate 631-61-8 17,741.1 0.00 17,741.14 18.6E-3 944.3E+3 449.2E-15 22.8E-6 570.3E-9
Ammonium chloride 12125-02-9 11,699.0 0.00 11,699.02 48.0E-3 35.5E+6 1.2E-12 857.7E-6 21.4E-6
Ammonium dihydrogen phosphate 7722-76-1 2.8 0.00 2.83
Ammonium hydroxide 1336-21-6 1.3 0.00 1.29
Ammonium persulfate 7727-54-0 2,682.2 0.00 2,682.17 222.4E-18 1.3E+6 5.4E-27 31.2E-6 779.1E-9
Ammonium phosphite 13446-12-3 1.3 0.00 1.32 21.2E-18 141.6E+0 511.3E-30 3.4E-9 85.5E-12
Ammonium salt 6,732.3
Amphoteric surfactant 372.5
Antifoam 0.8
Apatite 64476-38-6 43.6 0.00 43.60 16.6E-15 701.9E+3 401.2E-27 17.0E-6 423.9E-9
Bentonite, benzyl (hydrogenated tallow alkyl) dimethylammonium stearate complex 121888-68-4 451.6
Biotite 1302-27-8 43.6 0.00 43.60 16.2E-15 701.9E+3 390.4E-27 17.0E-6 423.9E-9
Borate 7550-67-7 45.8 0.00 45.78 1.9E-15 737.1E+3 46.3E-27 17.8E-6 445.2E-9
Calcite 471-34-1 895.3 0.00 895.27 118.8E-9 14.4E+6 2.9E-18 348.2E-6 8.7E-6
Calcium chloride 10043-52-4 958.3 0.00 958.30 3.6E-15 15.4E+6 87.5E-27 372.7E-6 9.3E-6
Carboxymethyl guar gum, sodium salt 39346-76-4 16,503.7
Chlorous acid, sodium salt 7758-19-2 8,802.1 0.00 8,802.06 18.4E-21 884.5E+0 444.8E-33 21.4E-9 534.2E-12
Choline chloride 67-48-1 6,265.0 0.00 6,264.99 2.4E-6 8.1E+3 57.8E-18 194.8E-9 4.9E-9
Cinnamaldehyde 104-55-2 0.0 0.00 0.00 1.0E+0 000.0E+0 24.3E-12 000.0E+0 608.6E-15
Citric acid 77-92-9 2.6 0.00 2.58 3.5E-6 4.1E+0 84.5E-18 99.2E-12 2.5E-12
Clay 334.8 0.00 334.76 49.2E-15 5.4E+6 1.2E-24 130.2E-6 3.3E-6
Cobalt acetate 71-48-7 192.2 0.09 192.12 1.4E+3 3.1E+6 33.3E-9 74.7E-6 1.9E-6
Dibromoacetonitrile 3252-43-5 108.7 108.73 0.00 1.2E+3 000.0E+0 29.3 E-9 000.0E+0 733.6E-12


44
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Didecyl dimethyl ammonium chloride 111-42-2 355.2 0.42 354.74 1.7E+0 1.4E+3 40.6E-12 34.3 E-9 857.3E-12
Diethylenetriamine 111-40-0 38.7 38.66 0.00 119.5E+0 000.0E+0 2.9E-9 000.0E+0 72.2E-12
Dinonyphenyl 9014-93-1 4.1 0.27 3.88 4.3E+3 62.4E+3 103.4E-9 1.5E-6 40.3 E-9
EDTA/copper chelate 14025-15-1 1,503.8 0.00 1,503.80 2.3E-15 4.1E+3 54.5E-27 98.4E-9 2.5E-9
EO~C7~9~iso, C8 rich-alcohols 78330-19-5 4.6 0.00 4.63 44.2E-3 1.6E+3 1.1E-12 37.5E-9 937.8E-12
EO-C9-11-iso, CIO-rich alcohols 78330-20-8 4.6 4.63 0.00 61.6E+0 000.0E+0 1.5E-9 000.0E+0 37.2E-12
Ethanol 64-17-5 48,995.2 48,995.20 0.00 19.8E+3 000.0E+0 478.0E-9 000.0E+0 12.0E-9
Ethoxylated branched C13 alcohol 78330-21-9 2,266.1 160.75 2,105.38 16.4E+3 215.0E+3 396.6E-9 5.2E-6 139.8E-9
Ethylene glycol 107-21-1 2,260.7 150.91 2,109.79 27.5E+0 385.1E+0 665.4E-12 9.3 E-9 249.2E-12
Fatty acids 0.7 0.71 0.00 11.5E+3 000.0E+0 277.0E-9 000.0E+0 6.9E-9
Fatty acids, tall oil 61790-12-3 591.9 0.39 591.53 4.6E+3 7.0E+6 111.3E-9 168.3E-6 4.2E-6
Formaldehyde amine resin 56652-26-7 1.8 1.85 0.00 22.8E+0 000.0E+0 551.2E-12 000.0E+0 13.8E-12
Formic acid 64-18-6 778.0 777.98 0.00 596.1E+0 000.0E+0 14.4E-9 000.0E+0 360.0E-12
Glutaraldehyde 111-30-8 1,106.3 1,106.30 0.00 220.1E+3 000.0E+0 5.3E-6 000.0E+0 132.9E-9
Glycerine 56-81-5 199.7 0.42 199.31 11.2E-3 5.4E+0 271.5E-15 129.5E-12 3.2E-12
Goethite 1310-14-1 128.7 0.00 128.75 2.9E-15 2.1E+6 70.0E-27 50.1E-6 1.3E-6
Guar gum 9000-30-0 100,655.4 0.00 100,655.40 1.1E-3 370.3E+6 26.5E-15 8.9E-3 223.6E-6
Haloalkyl heteropolycycle salt 0.2
Fleavy aliphatic petroleum naphtha solvent 64742-96-7 15.6 15.63 0.00 18.6E+0 000.0E+0 449.4E-12 000.0E+0 11.2E-12
Fleavy aromatic petroleum naphtha 64742-94-5 3,540.3 294.32 3,245.98 8.1E+3 89.6E+3 196.2E-9 2.2E-6 59.0E-9
Fleavy hydrotreated petroleum naphtha 64742-48-9 27,128.7 15,417.98 11,710.70 1.7E+6 1.3E+6 40.8E-6 31.0E-6 1.8E-6
Flexamethylenetetramine 100-97-0 1,631.3 15.15 1,616.13 2.5E+0 270.6E+0 61.3E-12 6.5E-9 164.9E-12
Flydrated magnesium silicate (talc) 14807-96-6 12.6 0.00 12.62 12.4E-15 203.2E+3 298.9E-27 4.9E-6 122.7E-9
Flydrochloric acid 7641-01-0 39,627.4 0.00 39,627.45 2.1E-15 1.1E+9 50.5E-27 27.1E-3 677.8E-6
Flydrotreated light petroleum distillate 64742-47-8 285,745.4 621.19 285,124.17 204.1E+3 93.7E+6 4.9E-6 2.3 E-3 56.7E-6


45
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Hydrotreated medium petroleum distillates 64742-46-7 6,296.1 87.79 6,208.29 81.1E+6 5.7E+9 2.0E-3 138.5E-3 3.5E-3
Inorganic base 36.5 0.00 36.51 6.2E-15 587.9E+3 149.7E-27 14.2E-6 355.0E-9
Isopropanol 67-63-0 4,937.6 4,937.63 0.00 224.9E+0 000.0E+0 5.4E-9 000.0E+0 135.8E-12
Isotridecanol, ethoxylated (TDA-6) 9043-30-5 770.6 0.00 770.57 174.0E-6 33.2E+3 4.2E-15 803.1E-9 20.1E-9
Lactic acid 50-21-5 2,447.4 198.07 2,249.29 463.4E-3 5.3E+0 11.2E-12 127.1E-12 3.5E-12
Laury alcohol ethoxylate 68551-12-2 14,482.7 143.63 14,339.07 104.0E+3 10.4E+6 2.5E-6 250.7E-6 6.3E-6
Light aromatic petroleum naphtha solvent 64742-95-6 2.8 2.77 0.00 98.3E+0 000.0E+0 2.4E-9 000.0E+0 59.4E-12
Magnesium oxide 1309-48-4 18.1 0.00 18.15 1.3E-15 292.2E+3 31.8E-27 7.1E-6 176.5E-9
Magnesium peroxide 14452-57-4 9.1 0.00 9.06 1.8E-15 145.9E+3 44.4E-27 3.5E-6 88.1E-9
Methanol 67-56-1 2,672.3 2,672.25 0.00 872.8E+0 000.0E+0 21.1E-9 000.0E+0 527.2E-12
Methyl isobutyl ketone 108-10-1 172.6 172.63 0.00 77.3E+0 000.0E+0 1.9E-9 000.0E+0 46.7E-12
Naphthalene 91-20-3 536.3 294.30 242.02 4.9E+3 4.0E+3 118.8E-9 97.7E-9 5.4E-9
Naphthenic acid ethoxylate 68410-62-8 94.9 0.00 94.87 142.0E-6 6.0E+3 3.4E-15 145.5E-9 3.6E-9
N-dimethyl formamide 68-12-2 0.0 0.00 0.00 925.2E-6 000.0E+0 22.4E-15 000.0E+0 558.8E-18
No hazardous ingredients 4.0
No MSDS ingredients (Friction Reducer) 96.1
Nonhazardous 156.2
Non-ionic surfactant 22.3
N-propanol zirconate 30.5
N-propyl zirconate 23519-77-9 3,617.9 0.00 3,617.89 425.5E-18 58.2E+6 10.3E-27 1.4E-3 35.2E-6
Olefin 64743-02-8 0.1 0.05 0.00 14.5E+0 000.0E+0 351. IE-12 000.0E+0 8.8E-12
Organic sulfonic acid 27176-87-0 6.5 0.00 6.52 3.0E-9 956.5E+0 71.5E-21 23.1E-9 577.7E-12
Organic sulfur compound 0.0
Oxirane, 2-methyl-, polymer with oxirane, monodecyl ether 37251-67-5 157.7 0.01 157.73 5.0E+0 59.6E+3 121.3E-12 1.4E-6 36.0E-9
Phenol/formaldehyde resin 9003-35-4 16,252.3 86.60 16,165.72 1.1E+3 199.7E+3 25.8E-9 4.8E-6 121.2E-9


46
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Poly(oxy-l,2-ethanediyl),.alpha.-tetradecyl-.omega .-hydroxy 27306-79-2 786.6 0.02 786.57 54.2E+0 2.7E+6 1.3E-9 66.4E-6 1.7E-6
Poly(tetrafluoroethylene) 9002-84-0 9.4 9.38 0.00 3.1E+0 000.0E+0 75.6E-12 000.0E+0 1.9E-12
Polyethylene glycol 25322-68-3 396.4 0.01 396.43 1.1E+0 83.4E+3 27.2E-12 2.0E-6 50.4E-9
Polyoxyalkylenes 68951-67-7 318.0 30.52 287.46 47.4E+3 446.4E+3 1.1E-6 10.8E-6 298.2E-9
Polyquaterna ry a mine 48.8
Polysaccharide 68130-15-4 31,931.4 0.00 31,931.35 817.3E-27 638.4E-3 19.7E-36 15.4E-12 385.6E-15
Potassium carbonate 584-08-7 7,394.9 0.00 7,394.87 788.1E-18 84.8E+0 19.0E-27 2.0E-9 51.2E-12
Potassium hydroxide 1310-58-3 3,365.3 0.00 3,365.26 866.5E-24 25.7E+0 20.9E-33 619.7E-12 15.5E-12
Potassium persulfate 7727-21-1 0.3 0.00 0.31 795.5E-21 452.9E-3 19.2E-30 10.9E-12 273.5E-15
Propanol 71-23-8 6,509.9 6,509.93 0.00 2.0E+3 000.0E+0 47.2E-9 000.0E+0 1.2E-9
Propargyl alcohol 107-19-7 32.0 31.97 0.00 16.4E+3 000.0E+0 395.8E-9 000.0E+0 9.9E-9
Proprietary sesquiolate 8007-43-0 7.8 0.00 7.81 2.8E-18 222.2E-3 67.4E-30 5.4E-12 134.2E-15
Propylene glycol 57-55-6 14.4 14.35 0.00 1.6E+0 000.0E+0 38.0E-12 000.0E+0 950.2E-15
Quaternary amine 7,984.7
Quaternary ammonium compound 122-18-9 0.0 0.00 0.04 341.3E-6 14.7E+0 8.2E-15 356. IE-12 8.9E-12
Quaternary ammonium compounds, bis (hydrogenated tallow alkyl)dimethyl, salts with montmorillonite 68911-87-5 7.8
Quaternary ammonium compounds, bis (hydrotreated tallow alkyl)dimethyl, salts with bentonite 68953-58-2 909.1
Quaternary ammonium salt 27.3 0.00 27.27 341.3E-6 9.4E+3 8.2E-15 226.4E-9 5.7E-9
Silica, amorphous fumed 7631-86-9 105.2 0.00 105.18 19.4E-18 16.8E+3 468.3E-30 404.7 E-9 10.1 E-9
Sodium bicarbonate 144-55-8 526.1 0.00 526.05 10.4E-6 14.0E+0 250.9E-18 339.0E-12 8.5E-12
Sodium bromide 7647-15-6 108.7 0.00 108.73 30.3E-18 15.8E+3 731.5E-30 381.5E-9 9.5E-9
Sodium chloride 7647-14-5 42,603.8 0.00 42,603.77 473.7E-18 170.4E+6 11.4E-27 4.1E-3 102.9E-6


47
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Sodium erythorbate 6381-77-7 0.8 0.00 0.78 12.4E-15 776.0E-3 299.5E-27 18.7E-12 468.6E-15
Sodium hydroxide 1310-73-2 174.8 0.00 174.81 61.1E-15 5.4E+6 1.5E-24 131.1E-6 3.3E-6
Sodium hypochlorite 7681-52-9 4,825.1 0.00 4,825.09 1.6E-18 49.6E+3 37.5E-30 1.2E-6 30.0E-9
Sodium iodide 7681-82-5 2.8 0.00 2.83 49.5E-18 461.6E+0 1.2E-27 11.2E-9 278.8E-12
Sodium lactate 72-17-3 758.9 0.00 758.91 2.7E-6 44.7E+0 65.5E-18 1.1E-9 27.0E-12
Sodium perborate tetra hydrate 10486-00-7 92.1 0.00 92.13 5.0E-15 1.5E+6 121.2E-27 35.8E-6 895.8E-9
Sodium persulfate 7775-27-1 144.2 0.00 144.17 1.5E-18 447.7E+0 36.2E-30 10.8E-9 270.4E-12
Sodium sulfate 7757-82-6 0.2 0.19 0.00 699.3E-3 000.0E+0 16.9E-12 000.0E+0 422.3E-15
Sorbitan monooleate polyoxyethylene derivative 9005-65-6 175.3 0.00 175.29 9.0E-27 3.2E+6 217.0E-39 77.4E-6 1.9E-6
Sorbitan, mono-9-octadecenoate, (Z) 1338-43-8 172.6 0.00 172.57 346.7E-9 502.0E+3 8.4E-18 12.1E-6 303.2E-9
Soybean oil methyl ester 67784-80-9 1,434.7 0.03 1,434.64 982.1E+0 48.3E+6 23.7E-9 1.2E-3 29.1E-6
Styrene acrylic copolymer 25085-34-1 545.8 0.76 545.02 4.4E+0 3.2E+3 106.0E-12 76.3 E-9 1.9E-9
Sucrose 57-50-1 0.2 0.00 0.21 43.0E-15 2.8E-3 1.0E-24 66.5E-15 1.7E-15
Surfactants 1,131.8 1,131.79 0.00 51.5E+0 000.0E+0 1.2E-9 000.0E+0 31.1E-12
Tall oil acid diethanolamide 68155-20-4 106.8 0.00 106.81 14.6E-6 265.7E+3 352.7E-18 6.4E-6 160.4E-9
Terpenes and terpenoids 68956-56-9 1,346.0 1,345.97 0.00 380.9E+0 000.0E+0 9.2E-9 000.0E+0 230.1E-12
Terpenes and terpenoids, sweet orange-oil 68647-72-3 32,901.6 5,299.60 27,601.97 1.1E+6 5.7E+6 26.3E-6 137.2E-6 4.1E-6
Tert-butyl hydroperoxide 75-91-2 380.0 379.99 0.00 13.7E+3 000.0E+0 329.8E-9 000.0E+0 8.2E-9
Tetramethyl ammonium chloride 75-57-0 162.9 0.00 162.95 186.9E-6 857.2E+0 4.5E-15 20.7E-9 517.7E-12
Thiourea polymer 68527-49-1 0.7 0.25 0.47 142.7E-3 269.9E-3 3.4E-12 6.5E-12 249.2E-15
Trade secret 1,909.1
Triethanolamine 102-71-6 7,491.0 0.01 7,490.99 4.1E-3 2.1E+3 98.9E-15 51.2E-9 1.3E-9
Triethanolamine zirconate 101033-44-7 665.7 0.00 665.71
Triethylene glycol 112-27-6 529.2 5.36 523.80 328.9E-3 32.2E+0 7.9E-12 777.2E-12 19.6E-12
Triisopropanol a mine 122-20-3 1.8 0.05 1.74 74.2E-3 2.6E+0 1.8E-12 61.9E-12 1.6E-12
Trimethylamine 75-50-3 34.7 34.71 0.00 14.2E+0 000.0E+0 343.9E-12 000.0E+0 8.6E-12


48
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Various oxides and trace elements (Fe203, CaO, and MgO) are the largest fractions 13,248.3 0.00 13,248.29 5.2E-15 213.3E+6 125.8E-27 5.2E-3 128.8E-6
Vinylidene chloride-methyl acrylate copolymer 25038-72-6 72.2 72.17 0.00 10.5E+3 000.0E+0 254.4E-9 000.0E+0 6.4E-9
Xylene 1330-20-7 2.6 2.61 0.00 42.3E+0 000.0E+0 1.0E-9 000.0E+0 25.5E-12
Zirconium complex 1,162.3
Zirconium sodium hydroxy lactate complex 113184-20-6 86.3 0.00 86.29 000.0E+0 1.4E+6 000.0E+0 33.6E-6 839.1E-9
Zirconium solution 372.4
Zirconium, acetate lactate oxo ammonium complexes 68909-34-2 14,017.1 0.00 14,017.07 246.8E-9 222.0E+0 6.0E-18 5.4E-9 134.1E-12
Table 12 Environmental impact for Weld County by chemical
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
2-butoxyethanol 111-76-2 442.0 20.82 421.21 17.3E+0 350.5E+0 11.6E-9 234.6E-9 24.6E-9
Acetic acid 64-19-7 16.6 16.64 0.00 13.8E+0 000.0E+0 9.2E-9 000.0E+0 921.6E-12
Alkyl amine surfactant 0.1
Amines, tallow alkyl, ethoxylated 61791-26-2 0.1 0.00 0.05 33.3E-9 5.5E+0 22.3E-18 3.7E-9 368.3E-12
Amphoteric surfactant 335.9
Cinnamaldehyde 104-55-2 0.5 0.51 0.00 272.9E+0 000.0E+0 182.7E-9 000.0E+0 18.3E-9
Crystalline silica, quartz 14808-60-7 746,410.3 0.00 746,410.33 1.9E-15 12.0E+9 1.3E-24 8.0E+0 804.4E-3


49
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air Emissions to Fresh Water Total Air Impact per Unit Energy Total Water Impact per Unit Energy Average Impact per Well per Unit Energy
(PDF.m3.day) (PDF.m3.day) (PDF.m3.day)/MJ (PDF.m3.day)/MJ (PDF.m3.day)/MJ
Disodium ethylene diaminediacetate 38011-25-5 0.0 0.00 0.03 24.2E-12 251.9E-9 16.2E-21 168.6E-18 16.9E-18
Enzyme 0.1
Ethoxylated decyl alcohol 0.2 0.23 0.00 5.1E+0 000.0E+0 3.4E-9 000.0E+0 339.2E-12
Ethylene glycol 107-21-1 306.3 145.78 160.56 26.6E+0 29.3E+0 17.8E-9 19.6E-9 3.7E-9
Fatty acids, tall oil 61790-12-3 0.4 0.38 0.00 4.5E+3 15.2E+0 3.0E-6 10.2E-9 299.0E-9
Glycerine 56-81-5 6.7 0.40 6.33 10.9E-3 170.3 E-3 7.3E-12 114.0E-12 12.1E-12
Guar gum 9000-30-0 2,719.3 0.00 2,719.31 1.1E-3 10.0E+6 708.3E-15 6.7E-3 669.6E-6
Hydrochloric acid 7641-01-0 1,782.6 0.00 1,782.56 2.0E-15 50.5E+6 1.4E-24 33.8E-3 3.4E-3
Isopropanol 67-63-0 1.4 1.36 0.00 61.8E-3 000.0E+0 41.3E-12 000.0E+0 4. IE-12
Laury alcohol ethoxylate 68551-12-2 0.7 0.71 0.00 510.3E+0 000.0E+0 341.6E-9 000.0E+0 34.2E-9
Methanol 67-56-1 442.0 442.02 0.00 144.4E+0 000.0E+0 96.6E-9 000.0E+0 9.7E-9
Nitrilotriacetate, trisodium salt (NTA) 5064-31-3 0.1 0.00 0.09 66.0E-9 1.0E-3 44.2E-18 696.3E-15 69.6E-15
Nitrogen 7727-37-9 433,766.0 0.00 433,765.96 2.7E-18 21.0E+6 1.8E-27 14.0E-3 1.4E-3
Organic polyol 6.7
Poly(oxy-l,2-ethaned iyl),. alpha. -tetra decyl-. omega.-hydroxy 27306-79-2 0.0 0.01 0.01 52.3E+0 24.9E+0 35.0E-9 16.7E-9 5.2E-9
Polyether 0.0
Sodium chloride 7647-14-5 7.2 0.00 7.24 457.6E-18 28.9E+3 306.3E-27 19.4E-6 1.9E-6
Sodium erythorbate 6381-77-7 2.0 0.00 1.99 12.0E-15 2.0E+0 8.0E-24 1.3E-9 132.3E-12
Sodium hydroxide 1310-73-2 0.1 0.00 0.05 59.0E-15 1.7E+3 39.5E-24 1.1E-6 111.8E-9
Sodium hydroxyacetate 2836-32-0 0.1 0.12 0.00 846.5E-6 000.0E+0 566.6E-15 000.0E+0 56.7E-15
Sucrose 57-50-1 15.4 0.00 15.38 41.5E-15 202.4E-3 27.8E-24 135.5E-12 13.5E-12
Tetrasodium ethylenediamine tetraacetate 64-02-8 1.7 0.00 1.67 31.8E-3 27.0E+3 21.3E-12 18.0E-6 1.8E-6


50
Chemical CAS Number Mass Removed from Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ
Trisodium ethylenediaminetriacetate 19019-43-3 0.1 0.00 0.05 7.1E-9 1.8E-3 4.8E-18 1.2E-12 122. IE-15


51
Table 12 and Table 11 depict the environmental impact for Weld and Las Animas counties, respectively. The column descriptions are as follows:
> Mass Removed from Well (kg) | the total mass that returns to the surface as flowback: fmx
> Evaporative Mass (kg) | the total mass that evaporates from the pit into the air: Emass
> Mass in Water (kg) | the total mass that remains in the pit after evaporation: Wmass
> Emissions to Rural Air (PDF.m3.day) | the product of the evaporative mass and the rural air categorization factor: CFRuraiAirEmass
> Emissions to Fresh Water (PDF.m3.day) | the product of the mass in water and the fresh water categorization factor: CEFreshWaterWmass
> Total Air Impact per Unit Energy (PDF.m3.day)/MJ | applies the functional unit to the
CFRuraiAirEmass
emissions to rural air generating the air impact per unit energy:
MJi
> Total Water Impact per Unit Energy (PDF.m3.day)/MJ | applies the functional unit to the
CFFreshwater^mass
emissions to freshwater generating the freshwater impact per unit energy:
MJt
> Average Impact per Well per Unit Energy (PDF.m3.day)/MJ | sums the rural air and
freshwater impacts per unit energy over the total wells in the analysis generating the impact of all chemicals used per well in that county:
(YJ(CFRuralAirEmass + C FpreSflwaferWmass)\ (17)
V ZWi) x ni
The summation of all chemicals from Equation 17 will produce the environmental impact for
all chemicals per average well in each county, shown in Table 13.


52
Table 13 Summary of impact for each county
Weld County, Regular Oil Las Animas County, Coal-
and Gas Wells Bed Methane Wells Average
Ratio
Average per Average Average per Average (LA/W)
Chemical per Well Chemical per Well
Mass Removed from Well (kg) 5.7E+3 21.5E+3 15.2E+3 44.0E+3 204.24%
Evaporative Mass (kg) 854.3E+0 2.8E+3 26.2E+0 62.9E+0 2.28%
Mass in Water (kg) 5.5E+3 17.8E+3 18.3E+3 43.9E+3 246.04%
Emission to Rural Air (PDF.m3.day) 703.9E+3 2.2E+6 229.0E+0 549.5E+0 0.02%
Emissions to Freshwater (PDF.m3.day) 63.5E+6 198.4E+6 3.4E+6 8.2E+6 4.11%
Total Air Impact per Unit Energy (PDF.m3.day/MJ) 17.0E-6 53.1E-6 153.3E-9 367.8E-9 0.69%
Total Water Impact per Unit Energy (PDF.m3.day/MJ) 1.5E-3 4.8E-3 2.3E-3 5.5E-3 113.87%
Average Impact per Unit Energy (PDF.m3.day/MJ) 4.8E-3 5.5E-3 112.63%
Delivering energy from coal-bed methane wells in Las Animas county produces 12.6% more impact from chemicals to the environment as traditional oil and gas wells in Weld County per unit energy delivered for the average hydraulic fracturing well. CBM wells had negligible absolute emissions to air and low absolute emissions to water compared to oil and gas wells, but the impact increases greatly when the relative impact of energy (the functional unit) output is included. In both cases the impact in air was three to six orders of magnitude smaller than the impact in water. There were several possible reasons for this difference:
The average well in Las Animas County produced 44.4% more energy over its lifetime than the average well Weld County, which aids in reducing the impact of CBM wells.
The fraction of chemicals that return in the flowback are very different for oil and gas wells (17.5%) compared to coal-bed methane (61.0%) wells in our assessment. This variable multiplied by the mass of a chemicals originating the injection fluid governs the mass of chemicals that enter the disposal pit, which was the mass used to ascertain the impact. The value of the flowback fraction is proportional to the impact chemicals will have on the well. The flowback fractions that were used
came from sparse data, relying on many variables, yielding a large range of possible values; flowback


53
fractions can range from 1 to 83%, and even for the Niobrara formation values between 8 and 27% are often as precise as can be reliable used3.
The same flowback fraction for both sets of wells would have the impact be greatly lessened for the CBM wells. A flowback of 19.7% for wells in Weld County would generated the same environmental impact per well as for wells in Las Animas if flowback remains the same. Conversely, a flowback of 54.2% for Las Animas wells would generate the same impact compared to Weld County.
As the flowback fraction increases our calculations say that the environmental impact would increase proportionally, but a large factor not included in our assessment is the impact of chemicals that remain underground. Due to the low flowback fraction for Weld County these chemicals might have a significant impact, but there is little information regarding these chemicals, so it was decided to leave them outside the scope of this analysis.
Wells in Weld County must be drilled to a deeper depth than in Las Animas, and as a result subterranean chemicals have a larger distance to migrate before they reach the surface or an aquifer. It is not known how much these chemicals will impact the environment or if they are safely
stratified within their wells.


54
7 Conclusions and Future Work
Qualitatively, the assessment seems to yield more accurate and precise results for Las Animas, due to only one company being used. The vast majority of wells drilled are from Pioneer Natural Resources, being the reason we only used wells operated by them; Weld County has dozens of operators. The geology in which wells were drilled in Las Animas is slightly more homogenous compared to Weld County, and as a result the fracking fluids used were all very similar. Because one company was used as an operator, the fracking fluid would be more similar for the coal-bed methane wells. In short, the variations between the Las Animas wells were smaller than Weld County.
Las Animas only 212 registered wells on FracFocus.org, but Weld County has 7,1312. The well selection process was entirely randomized, which meant the chances of getting two wells with very different fluid compositions was much higher in Weld County, especially because there were many different companies operating wells compared to Las Animas County. Ideally a random subsection would statistically yield the average results, it is very possible that the selection of wells caused the results to be skewed. This was very less likely in Las Animas County. Future research would aim to have a strong methodology for well selection, or, ideally, automate the well selection process to extract information out for every single well in each county. Most data acquired for the analysis was input manually, a very tedious process that greatly reduced the quantity of wells we could analyze. Our overall methodology employed through the analysis will work regardless of the method the data was acquired; the various sheets and databases generated through this research was developed to optimize future automation. Once all the data is acquired and cleaned, the further steps to analyze the wells, chemicals, output, and impact become relatively easy


55
Although there were not many inorganic compounds relative to the total chemical inventory, there were enough to cause problems as inorganics are not able to be predicted in EPISuite and ECOSAR. Finding a better way to include inorganic compounds would further increase the accuracy of any similar assessments.
The goal of this work was to identify a standard way of assessing chemicals that could be applied throughout the industry and apply them to any selection of wells and their chemicals. Although various methodologies exist to accomplish this goal, our literature review showed that they are fragmented, with sources, techniques, and assumptions largely devised per paper and not standardized with other research. Furthermore, this data does not exist in an easily extracted form and is disjointed in multiple locations and therefore is uneven between sources. Since USEtox is a widely-used model, we conclude that standardizing the data for input into USEtox makes the most sense. Our methodology is built around that assumption and all data is optimized for input into USEtox. A database of all chemicals found in hydraulic fracturing with their properties could be created (expanded from ours), which will be beneficial as it would have all the properties easily vetted by an applicable agency, probably the EPA, easily attainable, and most importantly standardized with others performing similar research. The best case values for properties that lack experimental data should be included for chemicals without data. As better estimates and experimental data is found it will be added to the database, increasing the accuracy as time progresses. Information need only be extracted, not researched from various sources and
prediction programs.


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REFERENCES
(1) Broderick, J.; Anderson, K.; Wood, R.; Paul, G.; Sharmina, M.; Footitt, A. Shale gas an updated assessment of environmental and climate change impacts; Manchester, 2011.
(2) FracFocus.orgfracfocus.org.
(3) US Environmental Protection Agency. Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources (External Review Draft); Washington, D.C., 2015.
(4) Aminto, A.; Olson, M. S. Four-compartment partition model of hazardous components in hydraulic fracturing fluid additives.!. Nat. GasSci. Eng. 2012, 7, 16-21.
(5) Flamm, K. Colorado oil and gas wells by the numbers http://www.denverpost.com/datacenter/ci_27519246/colorado-oil-and-gas-wells-by-numbers (accessed Jan 10, 2016).
(6) Petron, G.; Karion, A.; Sweeney, C.; Miller, B. R.; Montzka, S. A.; Frost, G. J.; Trainer, M.; Tans, P.; Andrews, A.; Kofler, J.; et al. A new look at methane and nonmethane hydrocarbon emissions from oil and natural gas operations in the Colorado Denver-Julesburg Basin. J. Geophys. Res. Atmos. 2014,119 (11), 6836-6852.
(7) US Environmental Protection Agency. Evaluation of Impacts to Underground Sources of Drinking Water by Hydraulic Fracturing of Coalbed Methane Reservoirs Final; 2004.
(8) US Energy Information Administration. Coalbed Methane Production, by State http://www.eia.gov/dnav/ng/ng_prod_coalbed_sl_a.htm (accessed Feb 16, 2016).
(9) US Energy Information Administration. Coalbed Methane Proven Reserves, by State http://www.eia.gov/dnav/ng/ng_enr_coalbed_a_EPG0_R51_Bcf_a.htm (accessed Feb 16, 2016).
(10) Warner, N. R.; Christie, C. A.; Jackson, R. B.; Vengosh, A. Impacts of Shale Gas Wastewater Disposal on Water Quality in Western Pennsylvania. Environ. Sci. Technol. 2013, 47 (20), 11849-11857.
(11) Lester, Y.; Ferrer, I.; Thurman, E. M.; Sitterley, K. A.; Korak, J.; Aiken, G.; Linden, K. G. Characterization of hydraulic fracturing flowback water in Colorado: Implications for water treatment. Sci. Total Environ. 2015, 512-513, 637-644.
(12) Immig, J. Toxic Chemicals in the Exploration and Production of Gas from Unconventional Sources. Natl. Toxics Netw. 2013, No. April.


57
(13) Ziemkiewicz, P.; Quaranta, J. D.; McCawley, M. Practical measures for reducing the risk of environmental contamination in shale energy production. Environ. Sci. Process. Impacts 2014,16 (7), 1692.
(14) Hauschild, M. Z.; Huijbregts, M. A. J.; Jolliet, O.; MacLeod, M.; Margni, M.; van de Meent, D.; Rosenbaum, R. K.; McKone, T. E. Building a Model Based on Scientific Consensus for Life Cycle Impact Assessment of Chemicals: The Search for Harmony and Parsimony. Environ. Sci. Technol. 2008, 42 (19), 7032-7037.
(15) Rosenbaum, R. K.; Bachmann, T. M.; Gold, L. S.; Huijbregts, M. A. J.; Jolliet, O.; Juraske, R.; Koehler, A.; Larsen, H. F.; MacLeod, M.; Margni, M.; et al. USEtoxthe UNEP-SETAC toxicity model: recommended characterisation factors for human toxicity and freshwater ecotoxicity in life cycle impact assessment. Int. J. Life Cycle Assess. 2008,13 (7), 532-546.
(16) Rosenbaum, R. K.; Huijbregts, M. A. J.; Henderson, A. D.; Margni, M.; McKone, T. E.; van de Meent, D.; Hauschild, M. Z.; Shaked, S.; Li, D. S.; Gold, L. S.; et al. USEtox human exposure and toxicity factors for comparative assessment of toxic emissions in life cycle analysis: sensitivity to key chemical properties. Int. J. Life Cycle Assess. 2011,16 (8), 710-727.
(17) Henderson, A. D.; Hauschild, M. Z.; van de Meent, D.; Huijbregts, M. A. J.; Larsen, H. F.; Margni, M.; McKone, T. E.; Rosenbaum, R. K.; Jolliet, O. USEtox fate and ecotoxicity factors for comparative assessment of toxic emissions in life cycle analysis: sensitivity to key chemical properties. Int. J. Life Cycle Assess. 2011,16 (8), 701-709.
(18) Vandecasteele, I.; Mari Rivero, I.; Sala, S.; Baranzelli, C.; Barranco, R.; Batelaan, O.; Lavalle, C. Impact of Shale Gas Development on Water Resources A Case Study in Northern Poland. Environ. Manage. 2015, 55 (6), 1285-1299.
(19) U.S. House of Representatives Committee on Energy and Commerce. Chemicals Used in Hydraulic Fracturing; 2011.
(20) FracFocus.org. Chemical Use http://fracfocus.org/chemical-use (accessed Oct 19, 2015).
(21) Stringfellow, W. T.; Domen, J. K.; Camarillo, M. K.; Sandelin, W. L.; Borglin, S. Physical, chemical, and biological characteristics of compounds used in hydraulic fracturing. J. Hazard. Mater. 2014, 275, 37-54.
(22) Chemicalize.org http://www.chemicalize.org/.
(23) PubChem.gov https://pubchem.ncbi.nlm.nih.gov/.
(24) ToxNet.gov http://toxnet.nlm.nih.gov/.
(25) US Environmental Protection Agency. Estimation Programs Interface Suite for Microsoft


58
Windows, v4.11. United States Environmental Protection Agency. Washington, DC, USA 2016.
(26) Mayo-Bean, K.; Moran-Bruce, K.; Meyland, W. M.; Ranslow, P. ECOSAR Methodology Document. US Environmental Protection Agency. May 2012, p 46.
(27) Mayo-Bean, K.; Moran-Bruce, K.; Nabholz, J. V.; Meyland, W. M.; Howard, P. H. ECOSAR Operation Manual. US Environmental Protection Agency. 2012, p 60.
(28) Huijbregts, M. A. J.; Meent, D. van de; Margni, M.; Jolliet, O.; Resenbaum, R.; McKone, T. E.; Hauschild, M. Z. USEtox 2.0 Manual: Organic Substance (v2). USEtox.org. 2015, p 18.
(29) Huijbregts, M. A. J.; Margni, M.; Hauschild, M. Z.; Jolliet, O.; McKone, T. E.; Resenbaum, R.; Meent, D. van de. USEtox 2.0 Manual: Inorganic Substance (v2). USEtox.org. USEtox August 25, 2015, p 18.
(30) Travis, C. C.; Arms, A. D. Bioconcentration of organics in beef, milk, and vegetation. Environ. Sci. Technol. 1988, 22 (3), 271-274.
(31) Clark, C. E.; Burnham, A.; Harto, C.; Horner, R. Hydraulic fracturing and shale gas production: Technology, Impacts, and Policy; 2013.
(32) Jiang, M.; Hendrickson, C. T.; Vanbriesen, J. M. Life cycle water consumption and wastewater generation impacts of a Marcellus shale gas well. Environ. Sci. Technol. 2014, 48 (3), 1911-1920.
(33) Puri, R.; King, G. E.; Palmer, I. D. Damage to Coal Permeability During Hydraulic Fracturing. In Low Permeability Reservoirs Symposium; Society of Petroleum Engineers: Denver, 1991.
(34) Mackay, D.; van Wesenbeeck, I. Correlation of Chemical Evaporation Rate with Vapor Pressure. Environ. Sci. Technol. 2014, 48 (17), 10259-10263.
(35) Colorado Oil and Gas Conservation Commission Website http://cogcc.state.co.us/#/home.
(36) Ferrer, I.; Thurman, E. M. Chemical constituents and analytical approaches for hydraulic fracturing waters. Trends Environ. Anal. Chem. 2015, 5, 18-25.
(37) Guerra, K. L.; Dahm, K. G.; Dundorf, S. Oil and Gas Produced Water Management and Beneficial Use in the Western United States. Sci. Technol. Progr. 2011, No. 157, 129.
(38) Huijbregts, M. A. J.; Margni, M.; Hauschild, M. Z.; Jolliet, O.; McKone, T. E.; Resenbaum, R.; Meent, D. van de. USEtox 2.0 User Manual (v2). USEtox.org. 2015, p 30.


59
Appendix A Annual Oil and Gas Production per Well
Table 14 Annual oil production values for wells in Weld County
Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
12459 5.76E+ 06 3.44E+ 06 3.18E+ 06 3.70E+ 06 4.53E+ 06 2.67E+ 06 2.39E+ 06 3.18E+ 06 2.58E+ 06 3.08E+ 06 1.84E+ 06 1.21E+0 6 1.53 E+ 07 4.20E+ 07 3.00E+ 07 1.01E+ 07 8.60E+ 06
12629 5.85E+ 06 8.56E+ 06 3.29E+ 06 5.57E+ 06 6.57E+ 06 1.21E+ 07 6.21E+ 06 4.35E+ 06 3.99E+ 06 3.16E+ 06 2.77E+ 06 3.03E+0 6 8.12E+ 06 9.23E+ 06 8.63E+ 06 7.82E+ 06 5.62E+ 06
19794 2.88E+ 06 3.11E+ 07 2.25E+ 07 2.93 E+ 07 2.49 E+ 07 2.59E+ 07 2.60E+ 07 2.65E+ 07 2.14E+ 07 1.86E+ 07 1.63E+ 07 9.94E+0 6 1.77E+ 05 9.79E+ 05 1.28E+ 06 5.93 E+ 05 4.70E+ 05
20613 0.00E+ 00 3.14E+ 07 1.17E+ 07 7.06E+ 06 5.78E+ 06 3.48E+ 06 2.86E+ 06 0.00E+ 00 0.00E+ 00 0.00E+ 00 9.91E+ 05 3.04E+0 7 1.30E+ 07 1.20E+ 07 1.57E+ 07 7.30E+ 06 5.78E+ 06
21028 2.63E+ 06 6.67E+ 06 6.36E+ 06 4.95E+ 06 3.16E+ 06 2.70E+ 06 4.67E+ 06 3.14E+ 06 1.74E+ 06 2.33E+ 07 1.12E+ 07 5.52E+0 6 6.07E+ 06 9.73 E+ 06 1.27E+ 07 5.90E+ 06 4.67E+ 06
21514 3.61E+ 05 1.28E+ 07 8.54E+ 06 6.57E+ 06 6.04E+ 06 4.81E+ 06 4.17E+ 06 4.48 E+ 06 8.59E+ 06 9.29E+ 06 4.80E+ 06 4.07E+0 6 3.84E+ 06 7.34E+ 06 9.57E+ 06 4.45 E+ 06 3.53E+ 06
24914 2.72E+ 07 7.43 E+ 07 2.59E+ 07 1.60E+ 07 1.19E+ 07 6.09E+ 06 0.00E+ 00 6.12E+ 03 7.48E+ 03 1.12E+ 04 7.39E+ 03 1.06E+0 4 9.08E+ 03 1.73 E+ 04 2.26E+ 04 1.05E+ 04 8.33E+ 03
25988 2.21E+ 07 6.32E+ 07 7.73E+ 06 8.40E+ 06 6.66E+ 06 2.23E+ 06 0.00E+ 00 7.95E+ 04 9.73E+ 04 1.46E+ 05 9.61E+ 04 1.37E+0 5 1.18E+ 05 2.25E+ 05 2.94E+ 05 1.37E+ 05 1.08E+ 05
29021 2.25E+ 07 2.43 E+ 07 1.29E+ 07 9.67E+ 06 9.10E+ 06 1.09E+ 07 1.01E+ 07 8.44E+ 06 1.03 E+ 07 1.55E+ 07 1.02E+ 07 1.46E+0 7 1.25E+ 07 2.39E+ 07 3.12E+ 07 1.45 E+ 07 1.15E+ 07
29022 2.77E+ 07 1.59E+ 07 7.81E+ 06 8.68E+ 06 3.83E+ 06 9.19E+ 06 6.19E+ 06 5.16E+ 06 6.32E+ 06 9.47E+ 06 6.24E+ 06 8.92E+0 6 7.66E+ 06 1.46E+ 07 1.91E+ 07 8.87E+ 06 7.03 E+ 06
30906 0.00E+ 00 1.01E+ 07 4.78E+ 06 1.92E+ 06 2.11E+ 06 1.28E+ 06 8.61E+ 05 7.19E+ 05 8.80E+ 05 1.32E+ 06 8.68E+ 05 1.24E+0 6 1.07E+ 06 2.04E+ 06 2.66E+ 06 1.24E+ 06 9.79E+ 05
31642 2.07E+ 07 2.04E+ 08 9.03 E+ 07 3.60E+ 07 2.91E+ 07 3.00E+ 07 2.02E+ 07 1.69E+ 07 2.07E+ 07 3.10E+ 07 2.04E+ 07 2.92E+0 7 2.51E+ 07 4.79E+ 07 6.24E+ 07 2.90E+ 07 2.30E+ 07
32368 1.23E+ 08 1.05E+ 08 3.49E+ 07 2.99E+ 07 1.45 E+ 07 1.34E+ 07 9.00E+ 06 7.52E+ 06 9.19E+ 06 1.38E+ 07 9.08E+ 06 1.30E+0 7 1.12E+ 07 2.13E+ 07 2.78E+ 07 1.29E+ 07 1.02E+ 07
32457 6.65E+ 07 1.40E+ 08 8.19E+ 07 4.57E+ 07 3.09E+ 07 2.85E+ 07 1.92E+ 07 1.60E+ 07 1.96E+ 07 2.94E+ 07 1.94E+ 07 2.77E+0 7 2.38E+ 07 4.55E+ 07 5.93E+ 07 2.76E+ 07 2.18E+ 07
32795 8.19E+ 06 3.09E+ 07 1.17E+ 07 9.75E+ 06 8.49 E+ 06 7.85E+ 06 5.29E+ 06 4.41E+ 06 5.40E+ 06 8.09E+ 06 5.33E+ 06 7.63E+0 6 6.55E+ 06 1.25E+ 07 1.63E+ 07 7.59E+ 06 6.01E+ 06
33361 1.34E+ 08 9.48E+ 07 5.29E+ 07 4.16E+ 07 3.05E+ 07 2.82E+ 07 1.90E+ 07 1.59E+ 07 1.94E+ 07 2.91E+ 07 1.92E+ 07 2.74E+0 7 2.35E+ 07 4.50E+ 07 5.86E+ 07 2.73E+ 07 2.16E+ 07
34060 1.04E+ 06 1.12E+ 07 8.40E+ 06 5.67E+ 06 7.62E+ 06 7.05E+ 06 4.75E+ 06 3.97E+ 06 4.85E+ 06 7.27E+ 06 4.79E+ 06 6.85E+0 6 5.88E+ 06 1.12E+ 07 1.46E+ 07 6.81E+ 06 5.40E+ 06
34062 3.14E+ 06 8.96E+ 07 2.40E+ 07 5.24E+ 06 7.19E+ 06 6.65E+ 06 4.48 E+ 06 3.74E+ 06 4.58E+ 06 6.86E+ 06 4.52E+ 06 6.47E+0 6 5.55E+ 06 1.06E+ 07 1.38E+ 07 6.43 E+ 06 5.09E+ 06
34066 2.47E+ 06 7.70E+ 06 8.12E+ 06 3.79E+ 06 4.16E+ 06 3.85E+ 06 2.59E+ 06 2.16E+ 06 2.65E+ 06 3.97E+ 06 2.61E+ 06 3.74E+0 6 3.21E+ 06 6.13E+ 06 7.99E+ 06 3.72E+ 06 2.95E+ 06
34068 3.05E+ 06 1.93E+ 07 8.36E+ 06 1.87E+ 06 5.21E+ 06 4.82E+ 06 3.25E+ 06 2.71E+ 06 3.32E+ 06 4.97E+ 06 3.27E+ 06 4.69E+0 6 4.02E+ 06 7.69E+ 06 1.00E+ 07 4.66E+ 06 3.69E+ 06


60
Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
34509 2.27E+ 4.64E+ 1.53 E+ 6.46E+ 9.15E+ 8.47 E+ 5.70E+ 4.76E+ 5.82E+ 8.73 E+ 5.75E+ 8.23E+0 7.06E+ 1.35E+ 1.76E+ 8.18E+ 6.48 E+
06 07 07 06 06 06 06 06 06 06 06 6 06 07 07 06 06
36279 2.04E+ 8.64E+ 3.11E+ 1.02E+ 7.45E+ 6.89E+ 4.64E+ 3.87E+ 4.74E+ 7.10E+ 4.68E+ 6.70E+0 5.75E+ 1.10E+ 1.43 E+ 6.66E+ 5.27E+
08 07 07 07 06 06 06 06 06 06 06 6 06 07 07 06 06
36468 1.42E+ 6.07E+ 3.73E+ 1.22E+ 8.91E+ 8.24E+ 5.55E+ 4.64E+ 5.67E+ 8.50E+ 5.60E+ 8.01E+0 6.88E+ 1.31E+ 1.71E+ 7.97E+ 6.31E+
08 07 07 07 06 06 06 06 06 06 06 6 06 07 07 06 06
36853 2.32E+ 2.53E+ 1.14E+ 3.72E+ 2.73E+ 2.52E+ 1.70E+ 1.42E+ 1.74E+ 2.60E+ 1.71E+ 2.45E+0 2.10E+ 4.02E+ 5.24E+ 2.44E+ 1.93 E+
08 08 08 07 07 07 07 07 07 07 07 7 07 07 07 07 07
36855 2.54E+ 3.69E+ 1.64E+ 5.34E+ 3.91E+ 3.62E+ 2.44E+ 2.03 E+ 2.49 E+ 3.73E+ 2.46E+ 3.52E+0 3.02E+ 5.77E+ 7.52E+ 3.50E+ 2.77E+
08 08 08 07 07 07 07 07 07 07 07 7 07 07 07 07 07
36856 1.92E+ 2.68E+ 1.36E+ 4.46E+ 3.26E+ 3.02E+ 2.03 E+ 1.70E+ 2.08E+ 3.11E+ 2.05E+ 2.93E+0 2.52E+ 4.81E+ 6.27E+ 2.92E+ 2.31E+
08 08 08 07 07 07 07 07 07 07 07 7 07 07 07 07 07
37401 8.00E+ 1.98E+ 1.04E+ 3.39E+ 2.48E+ 2.30E+ 1.55E+ 1.29E+ 1.58E+ 2.37E+ 1.56E+ 2.23E+0 1.92E+ 3.66E+ 4.77E+ 2.22E+ 1.76E+
07 08 08 07 07 07 07 07 07 07 07 7 07 07 07 07 07
37728 1.44E+ 2.59E+ 1.28E+ 4.17E+ 3.05E+ 2.82E+ 1.90E+ 1.59E+ 1.94E+ 2.91E+ 1.92E+ 2.74E+0 2.36E+ 4.50E+ 5.86E+ 2.73E+ 2.16E+
08 08 08 07 07 07 07 07 07 07 07 7 07 07 07 07 07
37790 1.84E+ 1.10E+ 3.97E+ 1.30E+ 9.49 E+ 8.77E+ 5.91E+ 4.93E+ 6.04E+ 9.05E+ 5.96E+ 8.53E+0 7.32E+ 1.40E+ 1.82E+ 8.48E+ 6.72E+
08 08 07 07 06 06 06 06 06 06 06 6 06 07 07 06 06
38169 1.88E+ 1.34E+ 4.83 E+ 1.58E+ 1.15E+ 1.07E+ 7.19E+ 6.01E+ 7.35E+ 1.10E+ 7.25E+ 1.04E+0 8.91E+ 1.70E+ 2.22E+ 1.03 E+ 8.17E+
08 08 07 07 07 07 06 06 06 07 06 7 06 07 07 07 06
38415 3.76E+ 2.55E+ 9.19E+ 3.00E+ 2.20E+ 2.03 E+ 1.37E+ 1.14E+ 1.40E+ 2.10E+ 1.38E+ 1.98E+0 1.70E+ 3.24E+ 4.22E+ 1.96E+ 1.56E+
08 08 07 07 07 07 07 07 07 07 07 7 07 07 07 07 07
38416 5.02E+ 6.84E+ 2.46E+ 8.04E+ 5.89E+ 5.45E+ 3.67E+ 3.06E+ 3.75E+ 5.62E+ 3.70E+ 5.30E+0 4.55E+ 8.68E+ 1.13E+ 5.27E+ 4.17E+
08 08 08 07 07 07 07 07 07 07 07 7 07 07 08 07 07
39006 2.26E+ 1.21E+ 4.37E+ 1.43 E+ 1.05E+ 9.67E+ 6.52E+ 5.44E+ 6.65E+ 9.98E+ 6.57E+ 9.40E+0 8.07E+ 1.54E+ 2.01E+ 9.35E+ 7.41E+
08 08 07 07 07 06 06 06 06 06 06 6 06 07 07 06 06
39008 1.75E+ 1.38E+ 4.98E+ 1.63E+ 1.19E+ 1.10E+ 7.42E+ 6.20E+ 7.58E+ 1.14E+ 7.48E+ 1.07E+0 9.19E+ 1.76E+ 2.29E+ 1.06E+ 8.43 E+
08 08 07 07 07 07 06 06 06 07 06 7 06 07 07 07 06
39009 2.00E+ 1.16E+ 4.18E+ 1.36E+ 9.99E+ 9.24E+ 6.23E+ 5.20E+ 6.36E+ 9.53 E+ 6.28E+ 8.99E+0 7.71E+ 1.47 E+ 1.92E+ 8.93 E+ 7.08E+
08 08 07 07 06 06 06 06 06 06 06 6 06 07 07 06 06
39010 1.52E+ 1.10E+ 3.98E+ 1.30E+ 9.52E+ 8.81E+ 5.93E+ 4.95E+ 6.06E+ 9.08E+ 5.98E+ 8.56E+0 7.35E+ 1.40E+ 1.83E+ 8.51E+ 6.74E+
08 08 07 07 06 06 06 06 06 06 06 6 06 07 07 06 06
39088 1.52E+ 1.61E+ 5.82E+ 1.90E+ 1.39E+ 1.29E+ 8.67E+ 7.24E+ 8.85E+ 1.33E+ 8.74E+ 1.25E+0 1.07E+ 2.05E+ 2.67E+ 1.24E+ 9.85E+
08 08 07 07 07 07 06 06 06 07 06 7 07 07 07 07 06
39603 1.87E+ 1.99E+ 7.17E+ 2.34E+ 1.71E+ 1.59E+ 1.07E+ 8.92E+ 1.09E+ 1.64E+ 1.08E+ 1.54E+0 1.32E+ 2.53E+ 3.30E+ 1.53E+ 1.21E+
08 08 07 07 07 07 07 06 07 07 07 7 07 07 07 07 07
40388 1.42E+ 1.51E+ 5.44E+ 1.78E+ 1.30E+ 1.20E+ 8.10E+ 6.76E+ 8.27E+ 1.24E+ 8.17E+ 1.17E+0 1.00E+ 1.92E+ 2.50E+ 1.16E+ 9.21E+
08 08 07 07 07 07 06 06 06 07 06 7 07 07 07 07 06
40503 1.70E+ 1.81E+ 6.52E+ 2.13E+ 1.56E+ 1.44E+ 9.72E+ 8.11E+ 9.92E+ 1.49E+ 9.80E+ 1.40E+0 1.20E+ 2.30E+ 3.00E+ 1.39E+ 1.10E+
08 08 07 07 07 07 06 06 06 07 06 7 07 07 07 07 07
Average, 1.10E+ 1.17E+ 4.20E+ 1.37E+ 1.00E+ 9.29E+ 6.26E+ 5.22E+ 6.39E+ 9.58E+ 6.31E+ 9.03E+0 7.75E+ 1.48E+ 1.93 E+ 8.97E+ 7.11E+
Emp. 08 08 07 07 07 06 06 06 06 06 06 6 06 07 07 06 06
Total, 4.38E+ 4.19E+ 1.13E+ 2.88E+ 2.01E+ 1.11E+ 6.26E+ 4.18E+ 3.83E+ 5.75E+ 3.78E+ 5.42E+0 4.65E+ 7.40E+ 3.86E+ 1.79E+ 1.42E+
Emp. 09 09 09 08 08 08 07 07 07 07 07 7 07 07 07 07 07
Change, Emp. 106.35 % 36.03% 32.66% 73.24% 92.50% 67.36% 83.48% 122.32 % 149.90 % 65.87% 143.10 % 85.85 % 191.05 % 130.33 % 46.52% 79.21%


61
Well API PY1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY10 PY11 PY12 PY13 PY14 PY15 PY16 PY17
Average, 1.10E+ 1.22E+ 5.04E+ 2.00E+ 1.51E+ 1.42E+ 9.75E+ 8.22E+ 9.74E+ 1.46E+ 9.62E+ 1.38E+0 1.18E+ 2.24E+ 2.85E+ 1.32E+ 1.05E+
Model 08 08 07 07 07 07 06 06 06 07 06 7 07 07 07 07 07
Total, 4.38E+ 4.89E+ 2.02E+ 7.99E+ 6.05E+ 5.66E+ 3.90E+ 3.29E+ 3.90E+ 5.84E+ 3.85E+ 5.50E+0 4.72E+ 8.95E+ 1.14E+ 5.30E+ 4.20E+
Model 09 09 09 08 08 08 08 08 08 08 08 8 08 08 09 08 08
Change, Model 111.52 % 41.24% 39.64% 75.81% 93.54% 68.88% 84.29% 118.47 % 149.90 % 65.87% 143.10 % 85.85 % 189.47 % 127.18 % 46.52% 79.21%
Model Reliance 14.17% 43.76% 63.96% 66.84% 80.32% 83.96% 87.29% 90.16% 90.16% 90.16% 90.16% 90.16 % 91.73% 96.61% 96.61% 96.61%
Table 15 Annual gas production values for wells in Weld County
Well API
12459
12629
19794
20613
21028
21514
24914
25988
29021
29022 30906 31642 32368 32457
PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
1.79E+0 1.38E+0 2.01E+0 2.72E+0 3.45 E+0 2.77E+0 1.94E+0 2.76E+0 2.02E+0 2.04E+0 2.03 E+0 1.60E+0 5.79E+0 6.73 E+0 1.06E+0 3.36E+0 2.83E+0
7 7 7 7 7 7 7 7 7 7 7 7 7 7 8 7 7
4.04E+0 3.01E+0 1.39E+0 1.32E+0 1.68E+0 1.54E+0 1.28E+0 1.34E+0 1.28E+0 1.34E+0 1.43 E+0 9.21E+0 1.06E+0 1.30E+0 1.10E+0 6.24E+0 4.64E+0
6 7 7 7 7 7 7 7 7 7 7 6 7 7 7 6 6
6.16E+0 3.17E+0 2.23 E+0 1.95E+0 2.01E+0 2.13 E+0 2.04E+0 1.89E+0 1.13 E+0 1.15E+0 1.01E+0 5.62E+0 5.63E+0 9.44E+0 2.80E+0 9.48 E+0 7.84E+0
6 7 7 7 7 7 7 7 7 7 7 6 4 5 6 5 5
2.06E+0 1.47E+0 9.19E+0 7.00E+0 5.63E+0 4.44E+0 3.22E+0 4.33E+0 1.30E+0 0.00E+0 2.64E+0 9.91E+0 1.01E+0 8.00E+0 2.37E+0 8.03E+0 6.64E+0
4 7 6 6 6 6 6 3 4 0 5 6 7 6 7 6 6
3.28E+0 5.65E+0 4.55 E+0 3.40E+0 2.56E+0 2.10E+0 2.72E+0 2.08E+0 1.76E+0 3.99E+0 2.65 E+0 1.45E+0 7.80E+0 9.82E+0 2.91E+0 9.86E+0 8.15E+0
7 7 7 7 7 7 7 7 7 7 7 7 6 6 7 6 6
1.24E+0 9.56E+0 1.20E+0 1.41E+0 1.35E+0 1.42E+0 1.51E+0 9.56E+0 9.43 E+0 1.11E+0 9.94E+0 1.57E+0 1.49E+0 1.75E+0 5.18E+0 1.76E+0 1.45E+0
6 6 7 7 7 7 7 6 6 7 6 7 7 7 7 7 7
1.19E+0 7.04E+0 3.88E+0 2.95E+0 2.51E+0 1.36E+0 0.00E+0 6.06E+0 6.36E+0 8.59E+0 7.25E+0 6.31E+0 9.03E+0 1.06E+0 3.14E+0 1.06E+0 8.80E+0
7 7 7 7 7 7 0 4 4 4 4 4 4 5 5 5 4
1.08E+0 6.02E+0 1.38E+0 8.88E+0 1.12E+0 5.12E+0 0.00E+0 4.95E+0 5.19E+0 7.01E+0 5.92E+0 5.15E+0 7.37E+0 8.65E+0 2.56E+0 8.68E+0 7.18E+0
7 7 7 6 7 6 0 5 5 5 5 5 5 5 6 5 5
2.06E+0 1.57E+0 8.73E+0 7.23 E+0 5.86E+0 9.10E+0 7.30E+0 7.48 E+0 7.84E+0 1.06E+0 8.94E+0 7.79E+0 1.11E+0 1.31E+0 3.87E+0 1.31E+0 1.08 E+0
7 7 6 6 6 6 6 6 6 7 6 6 7 7 7 7 7
2.03E+0 1.28E+0 7.51E+0 6.20E+0 4.46E+0 6.42E+0 5.35E+0 5.48E+0 5.74E+0 7.76E+0 6.55E+0 5.70E+0 8.16E+0 9.57E+0 2.83E+0 9.61E+0 7.94E+0
7 7 6 6 6 6 6 6 6 6 6 6 6 6 7 6 6
5.53E+0 2.20E+0 1.09 E+0 3.52E+0 1.17E+0 3.18E+0 2.93E+0 3.00E+0 3.15E+0 4.25E+0 3.59E+0 3.12E+0 4.47E+0 5.24E+0 1.55E+0 5.26E+0 4.35E+0
5 6 6 5 5 5 5 5 5 5 5 5 5 5 6 5 5
2.49E+0 4.43 E+0 2.93E+0 1.29E+0 8.86E+0 5.91E+0 5.44E+0 5.57E+0 5.84E+0 7.88E+0 6.65E+0 5.80E+0 8.29E+0 9.72E+0 2.88E+0 9.77E+0 8.07 E+0
6 7 7 7 6 6 6 6 6 6 6 6 6 6 7 6 6
4.27E+0 5.94E+0 3.76E+0 3.38E+0 4.30E+0 3.91E+0 3.60E+0 3.69E+0 3.87E+0 5.23E+0 4.41E+0 3.84E+0 5.49 E+0 6.44E+0 1.91E+0 6.47E+0 5.35E+0
6 6 6 6 6 6 6 6 6 6 6 6 6 6 7 6 6
2.23E+0 5.28E+0 4.22E+0 3.05E+0 1.37E+0 1.25E+0 1.15E+0 1.17E+0 1.23E+0 1.66E+0 1.40E+0 1.22E+0 1.75E+0 2.05E+0 6.08E+0 2.06E+0 1.70E+0
7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7


32795
33361
34060
34062
34066
34068
34509
36279
36468
36853
36855
36856
37401
37728
37790
38169
38415
38416
39006
39008
39009
39010
39088
5.54E+0
6
4.01E+0
7
1.79E+0
7
1.54E+0
7
1.33E+0
7
1.21E+0
7
1.11E+0
7
1.14E+0
7
1.20E+0
7
1.62E+0
7
1.36E+0
7
1.19E+0
7
1.70E+0
7
1.99E+0
7
3.11E+0
7
6.02E+0
7
2.34E+0
7
1.91E+0
7
1.72E+0
7
1.57E+0
7
1.44E+0
7
1.48E+0
7
1.55E+0
7
2.09E+0
7
1.76E+0
7
1.54E+0
7
2.20E+0
7
2.58E+0
7
6.61E+0
4
6.07E+0
7
3.52E+0
7
1.21E+0
7
1.55E+0
7
1.41E+0
7
1.29E+0
7
1.32E+0
7
1.39E+0
7
1.88E+0
7
1.58E+0
7
1.38E+0
7
1.97E+0
7
2.31E+0
7
7.47E+0
4
5.30E+0
7
2.30E+0
7
1.09E+0
7
1.08E+0
7
9.86E+0
6
9.07E+0
6
9.29E+0
6
9.74E+0
6
1.32E+0
7
1.11E+0
7
9.67E+0
6
1.38E+0
7
1.62E+0
7
7.58E+0
4
3.52E+0
7
2.82E+0
7
1.13E+0
7
1.20E+0
7
1.09E+0
7
l.OOE+O
7
1.03E+0
7
1.08E+0
7
1.46E+0
7
1.23E+0
7
1.07E+0
7
1.53E+0
7
1.80E+0
7
4.30E+0
5
5.05E+0
7
2.77E+0
7
9.18E+0
6
1.16E+0
7
1.05E+0
7
9.68E+0
6
9.91E+0
6
1.04E+0
7
1.40E+0
7
1.19E+0
7
1.03 E+0 7
1.48E+0
7
1.73E+0
7
2.21E+0
5
2.14E+0
7
2.66E+0
7
1.64E+0
7
1.19E+0
7
1.08E+0
7
9.98E+0
6
1.02E+0
7
1.07E+0
7
1.45 E+0 7
1.22E+0
7
1.06E+0
7
1.52E+0
7
1.79E+0
7
8.19E+0
7
6.57E+0
7
3.65 E+0 7
1.28E+0
7
1.16E+0
7
1.05E+0
7
9.67E+0
6
9.91E+0
6
1.04E+0
7
1.40E+0
7
1.18E+0
7
1.03 E+0 7
1.47E+0
7
1.73E+0
7
4.25E+0
7
2.49 E+0 7
2.62E+0
7
9.19E+0
6
8.28E+0
6
7.53 E+0 6
6.93E+0
6
7.10E+0
6
7.44E+0
6
1.01E+0
7
8.49E+0
6
7.39E+0
6
1.06E+0
7
1.24E+0
7
7.54E+0
7
1.87E+0
8
2.34E+0
8
8.23E+0
7
7.42E+0
7
6.75E+0
7
6.21E+0
7
6.36E+0
7
6.67 E+0 7
9.01E+0
7
7.60E+0
7
6.62E+0
7
9.47E+0
7
1.11E+0
8
6.69E+0
7
2.17E+0
8
1.71E+0
8
6.02E+0
7
5.42E+0
7
4.93 E+0 7
4.54E+0
7
4.65E+0
7
4.87 E+0 7
6.58E+0
7
5.56E+0
7
4.84E+0
7
6.92E+0
7
8.12E+0
7
5.58E+0
7
1.64E+0
8
1.17E+0
8
4.10E+0
7
3.70E+0
7
3.36E+0
7
3.09E+0
7
3.17E+0
7
3.32E+0
7
4.49E+0
7
3.79E+0
7
3.30E+0
7
4.72E+0
7
5.54E+0
7
1.38E+0
7
7.41E+0
7
3.92E+0
7
1.38E+0
7
1.24E+0
7
1.13 E+0 7
1.04E+0
7
1.06E+0
7
1.12E+0
7
1.51E+0
7
1.27E+0
7
1.11E+0
7
1.58E+0
7
1.86E+0
7
4.03E+0
7
1.07E+0
8
9.11E+0
7
3.20E+0
7
2.88E+0
7
2.62E+0
7
2.41E+0
7
2.47E+0
7
2.59E+0
7
3.50E+0
7
2.96E+0
7
2.57E+0
7
3.68E+0
7
4.32E+0
7
5.19E+0
7
4.86E+0
7
2.70E+0
7
9.48E+0
6
8.54E+0
6
7.77E+0
6
7.15E+0
6
7.32E+0
6
7.68E+0
6
1.04E+0
7
8.75E+0
6
7.63 E+0 6
1.09E+0
7
1.28E+0
7
3.87E+0
7
4.66E+0
7
2.59E+0
7
9.08E+0
6
8.19E+0
6
7.45 E+0 6
6.85E+0
6
7.02E+0
6
7.36E+0
6
9.94E+0
6
8.39E+0
6
7.31E+0
6
1.04E+0
7
1.23E+0
7
1.29E+0
8
2.07E+0
8
1.15E+0
8
4.03 E+0 7
3.63E+0 7
3.30E+0
7
3.04E+0
7
3.11E+0
7
3.27E+0
7
4.41E+0
7
3.72E+0
7
3.24E+0
7
4.64E+0
7
5.44E+0
7
1.31E+0
8
4.80E+0
8
2.67 E+0 8
9.36E+0
7
8.44E+0
7
7.68E+0
7
7.06E+0
7
7.24E+0
7
7.59E+0
7
1.02E+0
8
8.65E+0
7
7.53E+0
7
1.08E+0
8
1.26E+0
8
8.58E+0
7
8.33E+0
7
4.63 E+0 7
1.62E+0
7
1.46E+0
7
1.33E+0
7
1.23 E+0 7
1.26E+0
7
1.32E+0
7
1.78E+0
7
1.50E+0
7
1.31E+0
7
1.87E+0
7
2.19E+0
7
7.13E+0
7
1.11E+0
8
6.16E+0
7
2.16E+0
7
1.95E+0
7
1.77E+0
7
1.63E+0
7
1.67E+0
7
1.75E+0
7
2.37E+0
7
2.00E+0
7
1.74E+0
7
2.49E+0
7
2.92E+0
7
9.82E+0
7
7.84E+0
7
4.35E+0
7
1.53 E+0 7
1.38E+0
7
1.25E+0
7
1.15E+0
7
1.18E+0
7
1.24E+0
7
1.67E+0
7
1.41E+0
7
1.23 E+0 7
1.76E+0
7
2.06E+0
7
7.24E+0
7
7.42E+0
7
4.12E+0
7
1.45E+0
7
1.30E+0
7
1.19E+0
7
1.09E+0
7
1.12E+0
7
1.17E+0
7
1.58E+0
7
1.34E+0
7
1.16E+0
7
1.67E+0
7
1.95E+0
7
5.22E+0
7
9.24E+0
7
5.13 E+0 7
1.80E+0
7
1.62E+0
7
1.48E+0
7
1.36E+0
7
1.39E+0
7
1.46E+0
7
1.97E+0
7
1.66E+0
7
1.45E+0
7
2.07E+0
7
2.43 E+0 7


63
Well API PY1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
39603 1.93E+0 3.41E+0 1.89E+0 6.65E+0 6.00E+0 5.46E+0 5.02E+0 5.14E+0 5.39E+0 7.28E+0 6.15E+0 5.35E+0 7.66E+0 8.98E+0 2.66E+0 9.02E+0 7.46E+0
8 8 8 7 7 7 7 7 7 7 7 7 7 7 8 7 7
1.26E+0 2.23E+0 1.24E+0 4.34E+0 3.91E+0 3.56E+0 3.27E+0 3.35E+0 3.52E+0 4.75E+0 4.01E+0 3.49E+0 4.99E+0 5.86E+0 1.74E+0 5.88E+0 4.86E+0
40388 8 8 8 7 7 7 7 7 7 7 7 7 7 7 8 7 7
8.37E+0 1.48E+0 8.22E+0 2.89E+0 2.60E+0 2.37E+0 2.18E+0 2.23E+0 2.34E+0 3.16E+0 2.67E+0 2.32E+0 3.32E+0 3.90E+0 1.15E+0 3.91E+0 3.24E+0
40503 7 8 7 7 7 7 7 7 7 7 7 7 7 7 8 7 7
Average, 4.26E+0 7.53E+0 4.18E+0 1.47E+0 1.32E+0 1.20E+0 1.11E+0 1.14E+0 1.19E+0 1.61E+0 1.36E+0 1.18E+0 1.69E+0 1.98E+0 5.87E+0 1.99E+0 1.65E+0
Empirical 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7
Total, 1.70E+0 2.71E+0 1.13E+0 3.08E+0 2.65E+0 1.45E+0 1.11E+0 9.08E+0 7.14E+0 9.64E+0 8.14E+0 7.09E+0 1.01E+0 9.91E+0 1.17E+0 3.98E+0 3.29E+0
Empirical 9 9 9 8 8 8 8 7 7 7 7 7 8 7 8 7 7
Change, Empirical 177.01% 55.52% 35.12% 90.14% 90.96% 92.02% 102.42% 104.83% 135.09% 84.40% 87.10% 143.00% 117.32% 296.20% 33.90% 82.67%
Average, 4.26E+0 8.79E+0 5.60E+0 2.34E+0 2.12E+0 1.90E+0 1.71E+0 1.72E+0 1.75E+0 2.36E+0 1.99E+0 1.74E+0 2.48E+0 2.91E+0 8.32E+0 2.82E+0 2.33E+0
Model 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7
Total, 1.70E+0 3.52E+0 2.24E+0 9.37E+0 8.48E+0 7.60E+0 6.83E+0 6.90E+0 7.00E+0 9.45E+0 7.98E+0 6.95E+0 9.94E+0 1.16E+0 3.33E+0 1.13E+0 9.32E+0
Model 9 9 9 8 8 8 8 8 8 8 8 8 8 9 9 9 8
Change, Model 206.56% 63.68% 41.84% 90.57% 89.58% 89.86% 101.00% 101.47% 135.09% 84.40% 87.10% 143.00% 117.09% 285.84% 33.90% 82.67%
Model Reliance 0.00% 22.88% 49.57% 67.07% 68.79% 80.98% 83.77% 86.83% 89.80% 89.80% 89.80% 89.80% 89.80% 91.48% 96.47% 96.47% 96.47%


64
Table 16 Annual production values for wells in Las Animas County (natural gas only)
Well API PY1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11
08280 4.2E+6 34.1E+6 12.0E+6 9.7E+6 794.9E+3 9.1E+6 171.0E+6 296.8E+6 295.9E+6 262.0E+6 249.9E+6
08908 423.5E+3 150.6E+6 54.5E+6 30.3E+6 24.0E+6 30.4E+6 20.1E+6 14.4E+6 44.6E+6 47.4E+6 76.6E+6
09386 264.3E+3 2.9E+6 10.3E+6 31.5E+6 21.5E+6 17.9E+6 20.7E+6 61.6E+6 62.7E+6 72.1E+6 116.5E+6
09490 13.5E+6 18.2E+6 6.5E+6 5.2E+6 161.4E+3 23.9E+6 58.8E+6 108.1E+6 116.9E+6 134.5 E+6 217.3E+6
09782 4.1E+6 8.4E+6 146.2E+3 1.6E+6 1.6E+6 980.9E+3 3.3E+6 6.0E+6 6.5E+6 7.5E+6 12.1E+6
09871 32.9E+6 131.8E+6 115.5E+6 95.0E+6 84.4E+6 51.5E+6 171.4E+6 314.7E+6 340.4E+6 391.8E+6 632.9E+6
09874 33.6E+6 154.1E+6 154.3E+6 126.0E+6 128.0E+6 78.1E+6 260.0E+6 477.5E+6 516.4E+6 594.5E+6 960.2E+6
09878 6.7E+6 22.8E+6 14.2E+6 9.6E+6 6.0E+6 3.7E+6 12.2E+6 22.5E+6 24.3E+6 28.0E+6 45.2E+6
09885 164.3E+6 132.9E+6 98.0E+6 62.3E+6 30.4E+6 18.6E+6 61.8E+6 113.6E+6 122.8E+6 141.4E+6 228.4E+6
09898 211.8E+6 309.8E+6 308.3E+6 310.4E+6 151.7E+6 92.6E+6 308.1E+6 565.8E+6 612.0E+6 704.4E+6 1.1E+9
Average, Empirical 47.2E+6 96.6E+6 77.4E+6 68.2E+6 33.3E+6 20.3E+6 67.7E+6 124.3E+6 134.4E+6 154.7 E+6 249.9E+6
Total, Empirical 471.8E+6 965.5E+6 773.8E+6 681.7E+6 266.5E+6 81.3E+6 270.7E+6 372.8E+6 403.2E+6 309.4E+6 249.9E+6
Change, Empirical - 204.6% 80.1% 88.1% 48.9% 61.0% 332.8% 183.6% 108.2% 115.1% 161.5%
Average, Model 47.2E+6 96.6E+6 77.4E+6 68.2E+6 44.9E+6 32.7E+6 108.8E+6 198.1E+6 214.2E+6 238.4E+6 367.7E+6
Total, Model 471.8E+6 965.5E+6 773.8E+6 681.7E+6 448.7E+6 326.8E+6 1.1E+9 2.0E+9 2.1E+9 2.4E+9 3.7E+9
Change, Model - 204.6% 80.1% 88.1% 65.8% 72.8% 332.8% 182.1% 108.2% 111.3% 154.3%
Model Reliance 0.0% 0.0% 0.0% 0.0% 40.6% 75.1% 75.1% 81.2% 81.2% 87.0% 93.2%


65
Appendix B Annual Production Water
Well
API
PY 1
Table 17 Annual produced water generated for wells in Weld County
PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
12459 14,532 10,122 3,024 12,264 29,568 26,334 18,774 24,822 19,740 17,850 126 4,452 32,634 35,070 89,040 19,530 16,968
12629 0 18,816 4,620 6,426 30,450 33,474 15,666 11,802 10,122 9,912 8,778 5,586 24,360 11,634 16,464 21,504 9,660
19794 0 0 0 0 0 0 0 0 0 0 0 0 0 11,718 26,975 10,492 6,808
20613 336 18,228 3,234 966 2,226 1,890 3,192 84 0 0 2,100 42,798 19,572 17,850 41,092 15,982 10,371
21028 11,508 21,462 21,168 19,110 13,356 20,118 28,560 19,278 4,956 76,398 34,608 26,796 11,508 38,304 88,178 34,295 22,255
21514 3,570 29,274 12,642 7,266 6,216 5,964 7,644 8,232 20,454 13,188 9,114 10,374 6,426 9,349 21,523 8,371 5,432
24914 0 9,114 16,842 8,736 5,964 1,638 0 0 0 0 0 0 0 0 0 0 0
25988 0 9,114 12,222 8,736 6,300 7,098 0 8,946 9,011 19,131 8,922 14,674 15,406 22,415 51,601 20,069 13,024
29021 0 1,764 2,898 8,946 2,730 16,884 2,352 2,823 2,844 6,038 2,816 4,631 4,862 7,074 16,285 6,334 4,110
29022 0 16,044 5,334 4,620 2,730 16,842 0 0 0 0 0 0 0 0 0 0 0
30906 0 0 2,394 672 3,150 5,544 5,544 6,655 6,703 14,232 6,637 10,916 11,461 16,675 38,386 14,930 9,688
31642 1,132,530 519,876 188,496 77,826 117,516 86,226 86,226 103,50 4 104,25 7 221,348 103,22 7 169,77 4 178,25 1 259,343 597,022 232,202 150,68 2
32368 936,306 249,354 110,124 139,020 83,790 47,154 19,418 23,309 23,479 49,848 23,247 38,233 40,142 58,404 134,449 52,292 33,933
32457 44,940 169,134 127,596 160,356 279,132 157,084 64,688 77,651 78,215 166,059 77,443 127,36 7 133,72 7 194,563 447,895 174,201 113,04 4
32795 33,096 35,070 5,418 4,704 5,334 3,002 1,236 1,484 1,495 3,173 1,480 2,434 2,555 3,718 8,559 3,329 2,160
33361 150,486 189,630 71,652 68,586 83,511 46,997 19,353 23,232 23,401 49,682 23,169 38,106 40,009 58,210 134,002 52,118 33,821
34060 0 36,750 15,708 6,090 21,756 12,243 5,042 6,052 6,096 12,943 6,036 9,927 10,423 15,165 34,910 13,578 8,811
34062 4,998 321,300 51,576 2,688 7,560 4,254 1,752 2,103 2,118 4,498 2,097 3,450 3,622 5,270 12,131 4,718 3,062
34066 3,948 22,932 19,698 17,640 14,280 8,036 3,309 3,972 4,001 8,495 3,962 6,516 6,841 9,954 22,914 8,912 5,783
34068 10,584 90,174 24,654 7,644 10,920 6,145 2,531 3,038 3,060 6,496 3,030 4,983 5,232 7,612 17,522 6,815 4,422
34509 30,954 163,128 34,650 4,704 14,532 8,178 3,368 4,043 4,072 8,645 4,032 6,631 6,962 10,129 23,318 9,069 5,885
36279 408,786 108,696 17,383 9,240 11,251 6,331 2,607 3,130 3,153 6,693 3,121 5,134 5,390 7,842 18,053 7,021 4,556
36468 565,152 165,312 130,830 69,542 84,676 47,652 19,623 23,556 23,727 50,374 23,492 38,637 40,566 59,021 135,870 52,844 34,292


66
Well
API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
36853 742,854 2,053,086 85,386 45,387 55,263 31,100 12,807 15,373 15,485 32,877 15,332 25,217 26,476 38,520 88,676 34,489 22,381
36855 772,674 2,929,794 117,642 62,532 76,140 42,849 17,645 21,181 21,335 45,297 21,124 34,742 36,477 53,072 122,174 47,518 30,835
36856 646,212 2,248,932 94,500 50,231 61,162 34,420 14,174 17,014 17,138 36,386 16,969 27,908 29,302 42,632 98,141 38,170 24,770
37401 821,142 324,156 151,284 80,415 97,914 55,102 22,691 27,238 27,436 58,250 27,165 44,678 46,909 68,249 157,112 61,106 39,653
37728 600,054 308,910 57,876 30,764 37,458 21,080 8,681 10,420 10,496 22,284 10,392 17,092 17,946 26,110 60,106 23,377 15,170
37790 363,636 59,094 9,451 5,023 6,117 3,442 1,417 1,702 1,714 3,639 1,697 2,791 2,930 4,263 9,815 3,817 2,477
38169 396,774 76,650 12,258 6,516 7,934 4,465 1,839 2,207 2,223 4,720 2,201 3,620 3,801 5,530 12,730 4,951 3,213
38415 29,904 61,824 9,887 5,255 6,399 3,601 1,483 1,780 1,793 3,807 1,775 2,920 3,066 4,460 10,268 3,994 2,592
38416 48,174 92,064 14,723 7,826 9,529 5,363 2,208 2,651 2,670 5,669 2,644 4,348 4,565 6,642 15,290 5,947 3,859
39006 746,928 278,082 44,472 23,639 28,783 16,198 6,670 8,007 8,065 17,123 7,986 13,134 13,789 20,063 46,185 17,963 11,657
39008 820,554 295,512 47,259 25,121 30,587 17,213 7,088 8,509 8,571 18,197 8,486 13,957 14,654 21,320 49,080 19,089 12,387
39009 761,670 255,444 40,851 21,714 26,440 14,879 6,127 7,355 7,409 15,729 7,335 12,064 12,667 18,429 42,425 16,501 10,708
39010 676,494 245,532 39,266 20,872 25,414 14,302 5,890 7,070 7,121 15,119 7,051 11,596 12,175 17,714 40,779 15,860 10,292
39088 1,043,826 952,440 152,317 80,964 98,583 55,478 22,846 27,424 27,624 58,648 27,351 44,983 47,229 68,715 158,186 61,524 39,924
39603 865,998 790,181 126,368 67,171 81,788 46,027 18,954 22,752 22,918 48,657 22,691 37,320 39,183 57,009 131,237 51,042 33,123
40388 717,444 654,632 104,691 55,648 67,758 38,131 15,703 18,849 18,986 40,310 18,799 30,918 32,461 47,229 108,724 42,286 27,441
40503 517,818 472,484 75,561 40,164 48,905 27,521 11,333 13,605 13,703 29,094 13,568 22,315 23,429 34,088 78,472 30,520 19,805
Average
Empiric al 348,097 317,622 50,795 27,000 32,876 18,501 7,619 9,146 9,212 19,558 9,121 15,001 15,750 22,915 52,752 20,517 13,314
Total, Empiric al 13,923,88 2 11,434,37 4 1,371,46 8 567,000 657,510 222,012 76,188 73,164 55,272 117,348 54,726 90,006 94,500 114,576 105,504 41,034 26,628
Change, Empiric al 91.25% 15.99% 53.15% 121.76% 56.28% 41.18% 120.04 % 100.73 % 212.31% 46.64% 164.47 % 104.99 % 145.49% 230.21% 38.89% 64.89%
Average Model 348,097 357,603 51,649 31,876 40,078 25,006 12,211 14,271 14,140 30,020 14,000 23,026 24,175 34,834 80,140 31,169 20,226
Total, 13,923,88 14,304,11 2,065,95 1,275,02 1,603,12 1,000,26 488,44 570,85 565,59 1,200,80 560,00 921,02 967,00 1,393,36 3,205,58 1,246,76 809,05
Model 2 1 7 5 0 0 4 4 2 8 5 1 7 5 9 0 4
Change, Model 102.73% 14.44% 61.72% 125.73% 62.39% 48.83% 116.87 % 99.08% 212.31% 46.64% 164.47 % 104.99 % 144.09% 230.06% 38.89% 64.89%


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Well
API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17
Model Reliance 0.00% 20.06% 33.62% 55.53% 58.99% 77.80% 84.40% 87.18% 90.23% 90.23% 90.23% 90.23% 90.23% 91.78% 96.71% 96.71% 96.71%


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Table 18 Annual produced water generated per well in Las Animas County
Well API PY1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11
08280 71,484 348,600 293,454 207,270 0 129,780 1,927,254 1,967,280 1,499,988 999,222 860,748
08908 0 1,303,596 1,289,358 2,559,984 1,380,120 743,484 830,676 890,526 1,395,198 1,828,302 1,113,135
09386 69,174 3,250,800 8,685,978 7,963,998 7,287,798 8,124,102 8,620,374 7,070,112 97,314 137,924 83,973
09490 8,264,550 15,588,300 11,479,986 12,159,420 1,154,580 366,996 988,554 1,058,127 318,944 452,040 275,218
09782 3,461,472 13,839,588 226,380 0 0 0 0 0 0 0 0
09871 594,216 1,555,890 1,212,498 1,246,560 830,424 1,312,140 1,732,852 1,854,808 559,081 792,389 482,434
09874 675,318 1,415,064 986,454 1,023,750 1,072,554 1,694,726 2,238,106 2,395,622 722,095 1,023,429 623,099
09878 145,362 396,270 312,438 299,460 127,512 201,480 266,080 284,807 85,847 121,672 74,078
09885 348,516 101,598 57,624 59,598 24,043 37,990 50,170 53,701 16,187 22,942 13,968
09898 6,255,522 6,955,704 9,784,656 11,206,818 4,521,020 7,143,594 9,434,045 10,098,002 3,043,767 4,313,947 2,626,483
Average, Empirical 1,988,561 4,475,541 3,432,883 3,672,686 1,481,624 2,341,091 3,091,715 3,309,306 997,500 1,413,762 860,748
Total, Empirical 19,885,614 44,755,410 34,328,826 36,726,858 11,852,988 9,364,362 12,366,858 9,927,918 2,992,500 2,827,524 860,748
Change, Empirical 225.1% 76.7% 107.0% 40.3% 158.0% 132.1% 107.0% 30.1% 141.7% 60.9%
Average, Model 1,988,561 4,475,541 3,432,883 3,672,686 1,639,805 1,975,429 2,608,811 2,567,299 773,842 969,187 615,314
Total, Model 19,885,614 44,755,410 34,328,826 36,726,858 16,398,051 19,754,291 26,088,111 25,672,985 7,738,421 9,691,866 6,153,135
Change, Model 225.1% 76.7% 107.0% 44.6% 120.5% 132.1% 98.4% 30.1% 125.2% 63.5%
Model Reliance 0.0% 0.0% 0.0% 0.0% 27.7% 52.6% 52.6% 61.3% 61.3% 70.8% 86.0%


69
Appendix C Identified Chemicals
In the following table 0 signifies that the chemical is not part of that category, while 1 signifies it is part of the category. In the Unknown category, 2 (green chemicals in Table 10) represents chemicals that use substitute chemicals and 3 (yellow chemicals in Table 10) mean that a chemical was unknown and could not be identified through any means employed. Italicized CAS numbers reference the CAS numbers for the substitute chemicals. The following table is organized by unknown then by alphabetical order.
Table 19 All 184 chemicals detected in all 50 wells
CHEMICAL
CAS NUMBER
IN
TRACI
IN
USETOX
UNKNOWN
INORGANIC
3RD PARTY ADDITIVE 0 0 3 0
INORGANIC BASE 0 0 3 1
NO HAZARDOUS INGREDIENTS 0 0 3 0
NO MSDS INGREDIENTS (FRICTION REDUCER) 0 0 3 0
NONHAZARDOUS 0 0 3 0
NON-IONIC SURFACTANT 0 0 3 0
ORGANIC POLYOL 0 0 3 0
ORGANIC SULFUR COMPOUND 0 0 3 0
POLYETHER 0 0 3 0
PROPRIETARY COMPONENT, BIOCIDE 0 0 3 0
PROPRIETARY COMPONENT, SURFACTANT 0 0 3 0
TRADE SECRET 0 0 3 0
ALKYL AMINE SURFACTANT 0 0 3 0
ALKYLENE OXIDE BLOCK POLYMER 0 0 3 0
AMINE SALTS 0 0 3 0
AMMONIUM SALT 0 0 3 0
AMPHOTERIC SURFACTANT 0 0 3 0
ANTI FOAM 0 0 3 0
APATITE 64476-38-6 0 0 3 1
BENTONITE, BENZYL(HYDROGENATED TALLOW ALKYL) DIMETHYLAMMONIUM STEARATE COMPLEX 121888-68-4 0 0 3 0
BIOTITE 1302-27-8 0 0 3 1


70
CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC
CARBOXYMETHYL GUAR GUM, SODIUM SALT 39346-76-4 0 0 3 0
ENZYME 0 0 3 0
HALOALKYL HETEROPOLYCYCLE SALT 0 0 3 0
N-PROPANOL ZIRCONATE 0 0 3 0
OXYALKYLATED FATTY ACID 0 0 3 0
POLYOXYALKYLENES SURFACTANT 0 0 3 0
POLYQUATERNARY AMINE 0 0 3 0
QUATERNARY AMINE 0 0 3 0
QUATERNARY AMMONIUM COMPOUNDS, BIS(HYDROGENATED TALLOW ALKYLJDIMETHYL, SALTS WITH MONTMORILLONITE 68911-87-5 0 0 3 0
QUATERNARY AMMONIUM COMPOUNDS, BIS(HYDROTREATED TALLOW ALKYLJDIMETHYL, SALTS WITH BENTONITE 68953-58-2 0 0 3 0
ZIRCONIUM COMPLEX 0 0 3 0
ZIRCONIUM SOLUTION 0 0 3 0
ALCOHOL AMINE 102-71-6 0 0 2 0
ALDEHYDE 50-00-0 0 0 2 0
ALKOXYLATED AMINE 68155-27-1 0 0 2 0
AMIDE 67700-97-4 0 0 2 0
AROMATIC ALDEHYDE 100-52-7 0 0 2 0
CLAY 12173-60-3 0 0 2 1
EDTA/COPPER CHELATE 0 0 2 0
ETHOXYLATED ALCOHOL 68439-45-2 0 0 2 0
ETHOXY LATED AMINE 61791-26-2 0 0 2 0
ETHOXYLATED DECYL ALCOHOL 68439-46-3 0 0 2 0
ETHOXYLATED FATTY ACID 61791-26-2 0 0 2 0
FATTY ACID TALL OIL AMIDE 61790-12-3 0 0 2 0
FORMALDEHYDE AMINE RESIN 9003-35-4 0 0 2 0
GUAR GUM DERIVATIVE 74299-50-6 0 0 2 0
INORGANIC SALT 7647-14-5 0 0 2 1
N-PROPYL ZIRCONATE 0 0 2 0
POLYACRYLATE 79-10-7 0 0 2 0
POLYSACCHARIDE 33404-34-1 0 0 2 0
QUATERNARY AMMONIUM SALT 122-18-9 0 0 2 0
SURFACTANTS 67-63-0 0 0 2 0
VARIOUS OXIDES AND TRACE ELEMENTS (FE203, CAO, AND MGO) ARE THE LARGEST FRACTIONS 1309-37-1 0 0 2 1
2,3-DIHYDROXYPROPYL- TRIMETHYLAMMONlUM CHLORIDE 34004-36-0 0 0 0 0
3-CHLORO-2-HYDROXYPROPYL- TRIMETHYLAZANIUM;CHLORIDE 3327-22-8 0 0 0 0


71
CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC
l-(BENZYL)QUINOLINIUM CHLORIDE 15619-48-4 0 0 0 0
1,2,3-TRIMETHYLBENZENE 526-73-8 1 0 0 0
1,2,4-TRI M ETHYLB ENZE N E 95-63-6 1 1 0 0
2,2-DIBROMO-3-NITRILOPROPIONAMIDE 10222-01-2 1 1 0 0
2-AMINE-2-METHYL-PROPANOL 124-68-5 1 1 0 0
2-BROMO-3-NITRILOPROPIONAMIDE 1113-55-9 0 0 0 0
2-BUTOXY ETHANOL 111-76-2 1 1 0 0
2-ETHYLHEXANOL 104-76-7 1 0 0 0
3,4,4-TRI M ETHYLOXAZO LI Dl N E 75673-43-7 1 0 0 0
4,4- Dl M ETHYLOXAZO LI Dl NE 51200-87-4 1 1 0 0
4-NONYLPHENYL 127087-87-0 0 0 0 0
ACETIC ACID 64-19-7 1 1 0 0
ACETIC ANHYDRIDE 108-24-7 1 1 0 0
ALKYL DIMETHYL BENZYL AMMONIUM CHLORIDE 68424-85-1 0 0 0 0
ALKYL PYRIDINE BENZYL QUATERNARY AMMONIUM CHLORIDE 68909-18-2 0 0 0 0
ALUMINUM OXIDE 1344-28-1 0 0 0 1
AMINES, COCO ALKYL, ETHOXYLATED 61791-14-8 0 0 0 0
AMINES, TALLOW ALKYL, ETHOXYLATED 61791-26-2 0 0 0 0
AMMONIUM ACETATE 631-61-8 1 1 0 0
AMMONIUM CHLORIDE 12125-02-9 1 0 0 1
AMMONIUM DIHYDROGEN PHOSPHATE 7722-76-1 0 0 0 1
AMMONIUM HYDROXIDE 1336-21-6 0 0 0 1
AMMONIUM PERSULFATE 7727-54-0 0 0 0 1
AMMONIUM PHOSPHITE 13446-12-3 0 0 0 1
BORATE 7550-67-7 0 0 0 1
CALCITE 471-34-1 0 0 0 0
CALCIUM CHLORIDE 10043-52-4 0 0 0 1
CHLOROUS ACID, SODIUM SALT 7758-19-2 0 0 0 1
CHOLINE CHLORIDE 67-48-1 1 1 0 0
CINNAMALDEHYDE 104-55-2 1 0 0 0
CITRIC ACID 77-92-9 1 1 0 0
COBALT ACETATE 71-48-7 1 0 0 0
CRYSTALLINE SILICA, QUARTZ 14808-60-7 0 0 0 1
DIBROMOACETONITRILE 3252-43-5 1 1 0 0
DIDECYL DIMETHYL AMMONIUM CHLORIDE 111-42-2 1 0 0 0
Dl ETHYLE NETRIAM1N E 111-40-0 1 1 0 0
DINONYPHENYL 9014-93-1 0 0 0 0


72
CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC
DISODIUM ETHYLENE DIAMINEDIACETATE 38011-25-5 0 0 0 0
EO-C7-9-ISO, C8 RICH-ALCOHOLS 78330-19-5 0 0 0 0
EO-C9-11-ISO, CIO-RICH ALCOHOLS 78330-20-8 0 0 0 0
ETHANOL 64-17-5 1 1 0 0
ETHOXYLATED BRANCHED C13 ALCOHOL 78330-21-9 0 0 0 0
ETHYLENEGLYCOL 107-21-1 1 1 0 0
FATTY ACIDS 0 0 0 0
FATTY ACIDS, TALL OIL 61790-12-3 0 0 0 0
FORMALDEHYDE;2-METHYLOXIRANE;(lE,3E)-4,5,5-TRI METHYLH EXA-1,3- DIEN-l-OL 29316-47-0 0 0 0 0
FORMALDEHYDE;2-METHYLOXIRANE;4- NONYLPHENOL;OXIRANE 63428-92-2 0 0 0 0
FORMIC ACID 64-18-6 1 1 0 0
GLUTARALDEHYDE 111-30-8 1 1 0 0
GLYCERINE 56-81-5 1 1 0 0
GOETHITE 1310-14-1 0 0 0 1
GUARGUM 9000-30-0 0 0 0 0
HEAVY ALIPHATIC PETROLEUM NAPHTHA SOLVENT 64742-96-7 0 0 0 0
HEAVY AROMATIC PETROLEUM NAPHTHA 64742-94-5 0 0 0 0
HEAVY HYDROTREATED PETROLEUM NAPHTHA 64742-48-9 0 0 0 0
HEXAMETHYLENETETRAMINE 100-97-0 1 1 0 0
HYDRATED MAGNESIUM SILICATE (TALC) 14807-96-6 0 0 0 1
HYDROCHLORIC ACID 7641-01-0 1 0 0 1
HYDROTREATED LIGHT PETROLEUM DISTILLATE 64742-47-8 0 0 0 0
HYDROTREATED MEDIUM PETROLEUM DISTILLATES 64742-46-7 0 0 0 0
ISOPROPANOL 67-63-0 0 1 0 0
ISOTRIDECANOL, ETHOXYLATED (TDA-6) 9043-30-5 0 0 0 0
LACTIC ACID 50-21-5 0 0 0 0
LAURY ALCOHOL ETHOXYLATE 68551-12-2 0 0 0 0
LIGHT AROMATIC PETROLEUM NAPHTHA SOLVENT 64742-95-6 0 0 0 0
MAGNESIUM OXIDE 1309-48-4 0 0 0 1
MAGNESIUM PEROXIDE 14452-57-4 0 0 0 1
MESITYLENE 108-67-8 1 1 0 0
METHANOL 67-56-1 1 1 0 0
METHYL ISOBUTYL KETONE 108-10-1 1 1 0 0
NAPHTHALENE 91-20-3 1 1 0 0
NAPHTHENIC ACID ETHOXYLATE 68410-62-8 0 0 0 0


73
CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC
N-DIMETHYL FORMAMIDE 68-12-2 1 1 0 0
NITRILOTRIACETATE, TRISODIUM SALT (NTA) 5064-31-3 0 1 0 0
NITROGEN 7727-37-9 1 0 0 1
OLEFIN 64743-02-8 0 0 0 0
ORGANIC SULFONIC ACID 27176-87-0 1 1 0 0
OXIRANE, 2-METHYL-, POLYMER WITH OXIRANE, MONODECYL ETHER 37251-67-5 0 0 0 0
PHENOL/FORMALDEHYDE RESIN 9003-35-4 0 0 0 0
POLY(OXY-l,2-ETHANEDIYL),.ALPHA.- TETRADECYL-.OMEGA.-HYDROXY 27306-79-2 0 0 0 0
POLY(TETRAFLUOROETHYLENE) 9002-84-0 0 0 0 0
POLYETHYLENE GLYCOL 25322-68-3 0 0 0 0
POLYOXYALKYLENES 68951-67-7 0 0 0 0
POTASSIUM CARBONATE 584-08-7 0 0 0 0
POTASSIUM HYDROXIDE 1310-58-3 0 0 0 0
POTASSIUM PERSULFATE 7727-21-1 0 0 0 1
PROPANOL 71-23-8 1 1 0 0
PROPARGYL ALCOHOL 107-19-7 1 1 0 0
PROPRIETARY SESQUIOLATE 8007-43-0 0 0 0 0
PROPYLENE GLYCOL 57-55-6 1 1 0 0
QUATERNARY AMMONIUM COMPOUND 122-18-9 0 0 0 0
SILICA, AMORPHOUS FUMED 7631-86-9 0 0 0 1
SODIUM BICARBONATE 144-55-8 0 0 0 0
SODIUM BROMIDE 7647-15-6 0 0 0 1
SODIUM CHLORIDE 7647-14-5 0 0 0 1
SODIUM ERYTHORBATE 6381-77-7 0 1 0 0
SODIUM HYDROXIDE 1310-73-2 0 0 0 1
SODIUM HYDROXYACETATE 2836-32-0 0 0 0 0
SODIUM HYPOCHLORITE 7681-52-9 0 0 0 1
SODIUM IODIDE 7681-82-5 0 0 0 1
SODIUM LACTATE 72-17-3 0 0 0 0
SODIUM PERBORATE TETRAHYDRATE 10486-00-7 0 0 0 1
SODIUM PERSULFATE 7775-27-1 0 0 0 1
SODIUM SULFATE 7757-82-6 0 0 0 1
SODIUM;PROP-2-ENAMIDE;PROP-2-ENOATE;PROP-2-ENOIC ACID 62649-23-4 0 0 0 0
SORBITAN MONOOLEATE POLYOXYETHYLENE DERIVATIVE 9005-65-6 0 0 0 0
SORBITAN, MONO-9-OCTADECENOATE, (Z) 1338-43-8 0 0 0 0
SOYBEAN OIL METHYL ESTER 67784-80-9 0 0 0 0
STYRENE ACRYLIC COPOLYMER 25085-34-1 0 0 0 0


74
CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC
SUCROSE 57-50-1 0 1 0 0
TALL OIL ACID DIETHANOLAMIDE 68155-20-4 0 0 0 0
TERPENES AND TERPENOIDS 68956-56-9 0 0 0 0
TERPENES AND TERPENOIDS, SWEET ORANGE-OIL 68647-72-3 0 0 0 0
TERT-BUTYL HYDROPEROXIDE 75-91-2 1 1 0 0
TETRAMETHYL AMMONIUM CHLORIDE 75-57-0 1 1 0 0
TETRASODIUM ETHYLENEDIAMINE TETRAACETATE 64-02-8 1 1 0 0
THIOUREA POLYMER 68527-49-1 0 0 0 0
TRIETHANOLAMINE 102-71-6 1 1 0 0
TRIETHANOLAMINE ZIRCONATE 101033-44-7 0 0 0 0
TRIETHYLENEGLYCOL 112-27-6 1 1 0 0
TRIM ETHYLAM1N E 75-50-3 1 1 0 0
TRIISOPROPANOLAMINE 122-20-3 0 1 0 0
TRISODIUM ETHYLENEDIAMINETRIACETATE 19019-43-3 0 0 0 0
VINYLIDENE CHLORIDE-METHYL ACRYLATE COPOLYMER 25038-72-6 0 0 0 0
WATER 7732-18-5 0 0 0 1
XYLENE 1330-20-7 1 0 0 0
ZIRCONIUM SODIUM HYDROXY LACTATE COMPLEX 113184-20-6 0 0 0 0
ZIRCONIUM, ACETATE LACTATE OXO AMMONIUM COMPLEXES 68909-34-2 0 0 0 0


Full Text

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A N ENVIRONMENTAL IMPACT ASSESSMENT OF CHEMICALS USED IN HYDRAULIC FRACTURING OPERATIONS FOR A SELECTION OF OIL AND GAS WELLS COMPARED TO COAL BED METHANE WELLS IN COLORADO by DAVID LAWRENCE ZELINKA B.S Purdue University 2013 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Masters of Science Civil Engineering 2016

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ii This thesis for the Master of Science degree by David Lawrence Zelinka has b een approved for the Civil Engineering Program By Bruce Janson Chair Arunprakash Karunanithi Azadeh Bolhari Date: 22 July 2016

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iii Zelinka, David Lawrence ( M.S., Civil Engineering) An Environmental Impact Assessment of Chemicals used in Hydraulic Frac turing Operations for A Selection of Oil and Gas Wells Compared to Coal Bed Methane Wells in Colorado Thesis directed by Associate Professor Arunprakash Karunanithi ABSTRACT This study estimates the environmental impact of chemicals used for hydraulic fr acturing (HF) operations for oil and gas (O&G) and coal bed methane (CBM) wells in Colorado in an effort to devise a standardized methodology to analyze the ecotoxicity and human health impact of chemicals The chemicals constituents of HF fluids were ana lyzed for 40 O&G and 10 CBM wells for Weld and Las Animas counties, respectively, by extracting their well specific HF fluid composition from the FracFocus HF chemical registry website. Using the USEtox human and ecotoxicological impact model we assessed all 184 detected chemicals, generated their categorization factors, and calculated their environmental impact per average well in each county in terms of the USEtox units of PDF.m 3 .day /MJ (potentially disappeared fraction of species at the endpoint level i ntegrated over the freshwater volume (m 3 ) and the duration of 1 day per megajoule (MJ) ). We found that CBM HF wells (0.00546 PDF.m 3 .day /MJ) on average produced 12.6% greater impact from their chemicals than O&G wells (0.00485 PDF.m 3 .day /MJ). Impact was highly sensitive to the fraction of HF fluid that returns to the surface as flowback, which average 17.5% for wells in Weld County and 61% for wells in Las Animas County The form and consent of this abstract are approved. I recommend its publication Appr oved: Arunprakash Karunanithi

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iv CONTENTS Chapter 1 Introduction and Background ................................ ................................ ................................ .............. 1 1.1 Hydraulic Fracturing and Well Operations ................................ ................................ ................... 2 1.1.1 Denver Julesburg Basin ................................ ................................ ................................ ......... 2 1.1.2 Raton Basin ................................ ................................ ................................ ............................ 4 1.3 Goals of this resea rch ................................ ................................ ................................ ................... 4 2 Methodology ................................ ................................ ................................ ................................ ....... 7 2.1 Procedure for generating chemical categorization factors by data availability ........................... 7 2.2 Acquiring chemical property data ................................ ................................ ................................ 9 2.2.1 Physio chemical properties required for USEtox ................................ ................................ .. 9 2.2.2 Physio chemical properties not required for USEtox ................................ .......................... 11 2.2.3 Environmental partitioning ................................ ................................ ................................ 12 2.3 Determining the duration of the injection phase ................................ ................................ ....... 12 2.4 Determining flowback fraction ................................ ................................ ................................ ... 13 2.5 Calculating residence time ................................ ................................ ................................ ......... 14 2.6 Calculating aqueous based and evaporative masses ................................ ................................ 16 3 Functional Unit ................................ ................................ ................................ ................................ .. 19 4 Hydraulic Fracturing Fl uid Analysis ................................ ................................ ................................ .... 20 4.1 Traditional oil & gas wells in Weld County ................................ ................................ ................. 20

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v 4.2 Coal bed methane wells in Las Animas County ................................ ................................ .......... 22 5 Oil, Gas, and Water Production ................................ ................................ ................................ ......... 24 5.1 Projection model ................................ ................................ ................................ ........................ 24 5.2 Energy produced by source ................................ ................................ ................................ ........ 25 5.2.1 Weld County ................................ ................................ ................................ ........................ 25 5.2.2 Las Animas County ................................ ................................ ................................ ............... 26 5.3 Pr oduced water analysis ................................ ................................ ................................ ............. 27 5.3.1 Weld County ................................ ................................ ................................ ........................ 27 5.3.2 Las Animas County ................................ ................................ ................................ ............... 28 6 Results and Discussion ................................ ................................ ................................ ....................... 30 6.1 Energy and produced water comparison ................................ ................................ ................... 30 6.2 Categorization factors ................................ ................................ ................................ ................ 31 6.3 Environmental impact assessment ................................ ................................ ............................. 41 7 Conclusions and Future Work ................................ ................................ ................................ ........... 54 References ................................ ................................ ................................ ................................ ............ 56 Appendix A Annual Oil and Gas Production per Well ................................ ................................ ........................... 59 B Annual Production Water ................................ ................................ ................................ .................. 65 C Identified Chemicals ................................ ................................ ................................ .......................... 69

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vi FIGURES Figure 1 Categorization factors methodology flowchart ................................ ................................ ....... 7

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vii TABLES Table 1 Assigned rate constants associated with BioWin3 ................................ ................................ ............ 10 2 Residence times and assumptions by county ................................ ................................ .................... 16 3 County specific variables for calculating the evaporative mass per chemical ................................ .. 17 4 Average hydraulic fracturing fluid for a sample set of 40 traditional oil and gas wells in Weld Coun ty ................................ ................................ ................................ ................................ .................. 21 5 Average hydraulic fracturing for a sample set of 10 coal bed methane wells in Las Animas, County ................................ ................................ ................................ ................................ .............................. 22 6 Total natural gas an ................................ .............. 25 ................................ ................ 26 8 Tota l produced water generated in gallons per well in Weld County ................................ ............... 27 9 Total produced water generated in gallons per well in Las Animas County ................................ ..... 28 10 Raw categorization factors for ecotoxicity ................................ ................................ ...................... 33 11 Environmental impact for Las Animas County by chemical ................................ ............................ 42 12 Envir onmental impact for Weld County by chemical ................................ ................................ ...... 48 13 Summary of impact for each county ................................ ................................ ............................... 52 14 Annual oil production values for wells i n Weld County ................................ ................................ .. 59 15 Annual gas production values for wells in Weld County ................................ ................................ 61 16 Annual production values for wells in Las Animas C ounty (natural gas only) ................................ 64 17 Annual produced water generated for wells in Weld County ................................ ......................... 65 18 Annual produced water generated per well in Las Animas County ................................ ................ 68 19 All 184 chemicals detected in all 50 wells ................................ ................................ ....................... 69

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viii EQUATIONS Air water partitioning, K aw ................................ ................................ ................................ .................... 11 Average Impact per Well per Unit Energy (PDF.m3.day)/MJ ................................ ............................... 46 Bioaccumulation factor in fish, BAF fish ................................ ................................ ................................ .. 10 Bio transfer factor for meat, BTF meat ................................ ................................ ................................ .... 10 Bio transfer factor for milk, BTF milk ................................ ................................ ................................ ....... 10 C alculation of residence time ................................ ................................ ................................ ............... 14 Chemical Evaporation Rate ................................ ................................ ................................ .................. 15 Chemical mass that remained i n the pit, W,mass ................................ ................................ ................ 17 Degradation rate in air, k degA ................................ ................................ ................................ .................. 9 Degradation rate in sediment, k degSd ................................ ................................ ................................ .... 10 Degradation rate in soil, k degSi ................................ ................................ ................................ ............... 10 Degradation rate in water, k degW (1/s) ................................ ................................ ................................ .. 10 Dissipation rates in above ground plant tissues, k dissP ................................ ................................ ......... 11 H ................................ ................................ ................................ ............................... 8 Or ganic carbon partitioning, K oc ................................ ................................ ................................ ........... 11 Partitioning coefficient between dissolved organic carbon and water, K doc ................................ ........ 10 Soil water partitioning, K d ................................ ................................ ................................ .................... 11

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1 1 Introduction and B ackground Hydraulic fracturing is a process to create fractures in subterranean rocks by inj ecting water, a proppant, and chemicals under high pressure to stimulate the flow of oil and/or gas Direc tional drilling is similar to vertical (traditional ) drilling except the drilling is capable of turning up to 90 degrees (horizontal); this enables an individual well to make viable previously unreachable deposits of oil and/or gas The increased output and efficiency of wells using fracking and directional drilling are largely responsible for the natural gas boom since 2000 1 According to F rac F ocus.org, which is the website of the national hydraulic fracturing (HF ) chemical registry that discloses the chemicals and volumes of those chemicals for most wells in the United States, there are over 105,000 registered wells that use HF ; only wells using HF are listed 2 The total count for new oil and gas wells is estimated to be approximately 250,000 for the decade between 2000 and 2010, averaging 25,000 new wells a year; this figure does not include the wells drilled from 1947 to 2000. The beginning of t drilling technologies, while the close of the decade saw that number climb to 60% indicating the widespread application of the technology. Similarly, HF became much more widespread: with 57% of all well s hydraulically fractured in 2005, a number that climbs to 78% to 99% in 2012, although exact figures are unknown 3 Taking into account the global natural gas and oil industry, it is estimated that 90% of all new wells are hydraulically fractured 4 Colorado alone has in excess of 90,000 active wells of which a large fraction was estimated to be hydraulically fractured and/or horizontally drilled. 37% of all wells in Colorado are found in Weld County, but 50% of all producing wells, making it the most productive county in Colorado regardless of the indicator employed which is why it was chosen as the county to be assessed 5 The next most p roductive county is Garfield County at 17% of all Colorado wells Some wells can be

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2 fractured again to re stimulate the flow of oil and/or natural gas after a well has already been fractured, following a production phase, with a nother production phase, bu t this process occurs on only wells that are assessed to be profitable with extra proven resources. The Denver Julesburg (DJ) fracturing rate at 14% compared to 1% for the national average, but only one well was refractured in Las Animas out of the 50 wells in our assessment 6 In addition to traditional oil and gas wells coal bed methane (CBM) wells also, although not necessarily, use hydraulic fracturing. CBM is m ethane produced from trapped gas that is adsorbed into coal deposits 7 Colorado produced more natural gas from CBM than any other state from the years of 2011 2014 (data is not available for later) 8 and had more pr oven reserves than any other 9 There are far fewer wells for co al bed methane than for traditional wells like in Weld County, but overall production is much lower as well. CBM occurs in the southern portion of Colorado in the Raton Basin, specifically in Las Animas County where the focus of our CBM research is locate d. Of the 211 CBM wells on the FracFocus Chemical Disclosure Database in Las Animas, Pioneer Natural Resources owned 140 of them, making them the largest operator by any measurement in that county and also the sole operator we used in our assessments. We ld County had 7 131 wells spread over dozens of operators 2 1.1 Hydraulic Fracturing and Well Operations 1.1.1 Denver Julesburg Basin Hydraulic fracturing is only one phase of the oil and gas well life cycle, and it has been used since 1947 in vertically drilled wells in conventional oil and gas deposits. The advent of directional drilling (frequently referred to as just horizontal drilling) saw HF use increase greatly, and it now constitu tes the vast majority of wells drilled today. Directional drilling and HF when used in

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3 conjunction, enables previously unreachable (unconventional) oil and gas deposits to be exploited, which has been the main source of the natural gas boom since 2000. Directional drilling enables well operators to exploit deposits that are otherwise impossible to reach, like deposits under large structures, on an angle, or otherwise located in areas not economically viable. HF fluids are composed of a base fluid, almos t always water (80 98%), a proppant, almost always sand (5 20%), and a mixture of chemicals (1 2%) 3 The first stage in this oil and gas life cycle is the site assessment and preparation. Following site preparation, construction materials are brought to the site and the well and all associated roads, pits, and equipment are constructed and set up for the future phases. Wells are drilled vertically first, and when they reach the depth of the formation the drill head is turned to an angle, which can be up to 90 degrees, and direction that maximizes the contact with the oil and gas. After the bore hole is dr illed at the well site the hydraulic fracturing fluid is injected downhole. As the production phase starts, signified by the oil and gas extraction, the hydraulic fracturing fluid injection stops and the oil and gas begins to flow to the surface 3 along with naturally other underground water with high pH, alkalinity, and other parameters 10,11 This production phases lasts for the majority of the lifetime of the well, which ranges from fiv e to 15 years, with 60 at the extreme end, but is much closer to the former value 3 After the first year of production the annual recovery typically drops by 50 75% 12 so that after about 10 years (less for many) most well production becomes negligable 13 Following the useful econo mic life of the well, the site is closed, the well hole is plugged, and the site is returned to its original state as much as possible depending on the laws in the area 3 underground return, which is classified as produced water. Water that returns originating during

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4 the hydraulic fracturing injection phase above ground is called flowback water. These definitions are what will be used for this paper, but in the industry they are often used interchangeably or have slightly different definitions. A summary of these def initions can be found compiled by the EPA 3 1.1.2 Raton Basin Hydraulic fracturing is often used for coal bed methane (CBM), although it is not a requirement. The CBM layer is usually much shallower (0.8 1.2 km) than traditional oil and gas wells (2.0 2.3 km) 3 CBM gas unlike traditional hydraulically fractured oil and gas wells, is not physically trapped within the fractures in the coal, but it is adsorbed within the coal 7 In CBM, fractures might already exist within the coal, but HF is used to increase the fracture size; if the fractures do not exist HF creates them 3 The HF fluid volume is less in CBM due to the shallower depth and less rigid geological formation in CBM areas Additionally, a smaller variety of chemicals generally, are required in lower volumes to stimulate these wells. At this point, operations differ between the two basins. Under the high pr essures the gas remains adsorbed in the coal. Naturally occurring underground water is pumped out reducing the pressure in the coal along with some of the injection chemicals As the pressure decreases the methane desorbs from the coal and is pumped to the surface. Produced water is larger than in conventional hydraulically fractured wells, like in the DJ Basin. In the DJ Basin produced water falls off proportionally to the oil and gas produced, but in CBM deposits produced water is inversely proporti onal to gas production 7 1.3 Goals of this research Determining the h uman health and ecotoxicity impacts requires the use of USEtox 14 17 which is a life cycle impact model based on scientific consensus for generating midpoint categorization factors for human and ecotoxicol ogical impacts 15 Most chem icals have not been previously assessed, so these had to be customized and manually generated; this was one of the

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5 main goals of this research. Data acquired for each chemical was inputted into USEtox to generate the impacts. The output was applied to kn ow n chemical masses found in the 5 0 wells. Due to the lack of data regarding the human toxicity, it was decided to omit human toxicity and just generated the ecotoxicity values. Most research does not focus on the impacts of the unknown chemicals; they pr imarily look at the entire life cycle of and oil and gas well while focusing on water, energy, and emissions. Of the papers that have looked at the chemicals most use only the chemicals that are known, while other look at chemicals that have already been i dentified, while ignoring chemicals with unknown properties 18 Various entities, especially the United States Environmental Protection Ag ency (EPA) 3 the United State s House of Representatives 19 and FracFocus.org 20 have identified well over 1,000 different chemicals co mmonly used in hydraulic fracturing operations, although many chemicals are unknown because they are used relatively infrequently; their combined impacts when summed over all wells merit analysis Some studies use these lists as the main source for the ch emicals in their analysis, but they do not identify chemicals themselves and rely on external sources, as was the case in Impact of Shale Gas Development on Water Resources A Case Study in Northern Poland 18 Out of the chemicals identified by t he EPA only 37 of the nearly 184 (21%) chemical were found in use in the 40 wells in Weld County. Relying on these external sources is a good starti ng point, but they do not represent a complete list the chemicals found in hydraulically fractured wells. Absent chemicals are generally uncommon and these lists usually focus on chemicals common to H F and from locations other than Colorado, primarily the Marcellus Shale. As a result, many of the assessments are hig h level and not well specific. We made our assessments by focusing on specific wells to acquire high resolution data that can be applied to less studied locations, like Weld County for our rese arch. Many of these uncommon chemicals are lacking physio chemical property data, and even more are lacking toxicity

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6 and human health data 3 and very few papers have had the main goal to find these data 18,21 Chemicals that have not been analyzed in detail, representing the majority of our chemicals, require prediction software or empirical studies that come with their own prob lems. Prediction software are best guesses and studies per chemical are costly and time consuming, but they are the only two ways to acquire the information to generate the categorization factors, or at the least, bring about understanding of the chemical Our standardized methodology could be applied by other researchers to expand the knowledge of chemicals and HF impacts on local levels (well or site specific). Colo rado; the only difference is that the Niobrara Basin produced oil and gas from traditional hydraulic fractured wells while the Raton Basin produced coal and almost excl usively gas from coal deposits.

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7 2 Methodology 2 .1 Procedure for generating chemical cat egorization factors by data availability Figure 1 C ategorization factors methodology flowchart fracturing fluid, co mpounds were found that had all degrees of available data, ranging from nothing and unknown chemicals to the exact TRACI categorization factors necessary to run an analysis. That databases used to acquire the experimental values were Chemicalize 22 PubChem 23 and Tox Net 24 shown as green boxes in Figure 1 Various models were used to fill in data gaps USEtox 14,15 US

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8 EPA Estimation Program Interface (EPISuite) 25 and ECOlogical Structure Activity Relationships (ECOSAR) 26,27 when experimental data did not exist, which can be seen in Figure 1 as orange boxes. From the original inventory of 184 identified chemicals, three unique groups of substances were recognized, when organized by data availability. I. 44 chemicals had their categorization factors complete in TRACI, so nothing extra was required. II. Five che micals were not in TRACI, but were in USEtox, so calculating the categorization factors was straight forward and involved only running the USEtox model. III. 135 chemicals were not in neither TRACI or USEtox, so their chemical properties and toxicity data had t o be manually located and inputted into the USEtox model to generate their categorization factors. In order to generate the remaining 135 categorization factors, the remaining chemicals were furt her reduced to three subgroups. I. 81 chemicals were able to hav e their factors generated, as their properties were available through experimental data or through the EPI Suite and ECOSAR prediction models. II. 21 chemicals of these were very close or identical to other known chemicals. The substitute chemical data w as ap plied to these chemicals. III. The remaining 33 were ambiguously named chemicals (surfactant, nonhazardous, inorganic base, proprietary, etc.), were lacking a CAS number, or were otherwise not able to be identified. For these chemicals the average categorizati on factors were applied from all the chemicals that could be identified. This categorization factors for these 33 were all the same as a result of applying the average To maintain a standard procedure for each chemical all chemicals were run through the USEtox model. Chemicals that existed in the USEtox database and in our database were chosen at random,

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9 and then their categorization factors were generated. These values were checked against the USEtox database for validity, and if they were close to the values found in the database, it was assumed that all chemicals would yield close factors. 2 .2 Acquiring c hemical property data In addition to the specific format and units USEtox requires for input, there are many formulae recommended to further fill in data gaps in a fashion that standardizes the generation of categorization factors 28,29 Standardized formulae and methodologies aid in reducing possible outliers and variability in preliminary values with data that is already inherently inexact or missing due to large assumptions and data prediction from the lack of experimental data. All formulae, methodologies, and assumptions were compiled to have a standardized algorithm for acquiring missing data. In all cases, experimental data is preferred before using prediction software and formulaic assump tions. The assumptions below are to be used only if exp erimental data cannot be found. 2 .2.1 Physio chemical properties r equired for USEtox Molecular weight MW (g/mole): can be found by summing the molecular weight of all atoms Octanol water partitioning K ow (dim ensionless): predict using the F ragment method in EPISuite k H (Pa m3/mole): if left blank USEtox automatically calculates internally using the formula The addition al conversion factors are added only to show that the units are not the same, but coincidentally the numbers cancel out, so the formula will work without the conversions. (1) Vapor pressure v p (Pa): predict using EPISuite; for solids the Modified Grain method should be used, and for liquids and gases either the Antoine or the Modified Grain methods could be used

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10 Water solubility Sol 25 (mg/L) predict usin g EPISuite which requires K OW and melting points; USEtox formula can be used to find the water solubility, but care should be used to avoid circle logic; only if constant formula be employed Degradation rate in air k degA (1/s): predi ct using the OVERALL OH Rate Constant (kOH) under AopWin in EPISuite, which is multiplied by the constant 1.5 x 10 6 (2 a ) (2b) (2c) Degradation of water, sediment, and soil : find the Biowin3 (Ultimate Survey Model) and, neglecting the values, use the time range to match the assigned rate constant in Table 1 Table 1 Assigned rate constants associated with BioWin3 BIOWIN3 OUTPUT ASSIGNED RATE CONSTANT (S 1 ) HOURS 4.7 x 10 5 HOURS TO DAYS 6.4 x 10 6 DAYS 3.4 x 10 6 DAYS TO WEEKS 9.3 x 10 7 WEEKS 5.3 x 10 7 WE EKS TO MONTHS 2.1 x 10 7 MONTHS 1.3 x 10 7 RECALCITRANT 4.5 x 10 8 Once the rate constant has been identified the formulae below were used to find the degradation rates for each environmental compartment Degradation rate in water k degW (1/s) (3) Degradation rate in soil k degSi (1/s) (4)

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11 Degradation rate in sediment k degSd (1/s) (5) 2 .2.2 Physio chemical properties not required for USEtox The following assumptions are for data that are not required to generated USEtox categorization factors, but do enhance the validity of the ou tput, especially for chemicals lacking experimental data. For any data not shown, QSAR values are preferred, but can be left blank if no experimental data exists. Partitioning coefficient between dissolved organic carbon and water K doc (L/kg): if left blank USEtox automatically calculates internally using the formula (6) Bio transfer factor for meat BTF meat (d ay /kg meat): if left blank USEtox automatically calculates interna lly using the formula 30 (7) Bio transfer factor for milk BTF milk (d ay /kg milk): if left blank USEtox automatically calculates in ternally using the formula 30 (8) Bioaccumulation factor in fish BAF fish (L/kg fish): if left blank USEtox automatically calculates inter nally using the formula (9) Dissipation rates in above ground plant tissues k dissP (1/s): if left blank USEtox automatically calculates internally using the formula (10)

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12 2 2. 3 Environmental p artitioning Organic carbon partitioning K oc (kg/L): predict using the Molecular Connectivity Index (MCI) in EPISuite, or if it is left blank USEtox automatically calculates internally using the formula (11) Soil water partitioning, K d (kg/L): if experimental data does not exist than the following formula is to be used; f oc is the fraction of organic carbon and is assumed to be 0.02 (12) Air water partitioning, K aw (dimensionless): if experimental data does not exist than the following formula is to be used (13) 2 .3 Determining the duration of the injection phase The time when the hydraulic fracturing injection phase ends and the production phase begins is not a discrete point. For a similar reason that differentiating flowback from produced water is difficult, so is the point at which the two phases separate. The two phases are fundamentally interconnected so no one distinct definition exists to delineate the two 31 Multiple ways to det ermine when the injection phase turns into the production phase are used: the time required to injected all the hydraulic fracturing fluid; the time until produced water is greater than flowback water; the point at which oil and gas collection starts 3,31 The duration of the injection phase is the point when the hydraulic fracturing begins to be pumped underground to when the production phase starts, using one of the previous definitions. This information was not available per well and is at best difficult to find per deposit, so generic industry values were used. 14 days is the most cited in literature, so we used this value whenever

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13 injection phase duration was needed for shale specifically for calculating disposal pit residence times 3,31 32 The only avail able data for injection duration for CBM was analyzed for a 19 day period, so this value was used for CBM wells 7 2 4 Determining f lowback fraction Although the fraction of injected hydraulic fracturing fluid that returns as flowback water can be highly variable, this amount his correlated to the deposit in which the a wel l is drilled. In a selection of nine deposits the EPA has shown a list of low and high estimates for flowback water for an average well located on each of these deposits. Values range from 6 11% on the low end and 5 48% on the high end. More specificall y, Niobrara, above which Weld County sits, is listed as having a range between 8 and 27%, with an average at 17.5%. This value is used through this paper as a the constant flowback fraction since a well specific data to calculate flowback fraction is curr ently not possible to ascertain 3 Most wells will have a flowback ratio much closer to the low estim ate, which in the case of the Niobrara would most likely be 10%, but there is not enough data so we went with the average. Produced water is subject to even higher variations then flowback water. By definition enters the well, but produced water can range from 10 to 300% of the infected water volume depending on the life of the well 31 Data for flowback rates for the Raton Basin and coalbed methane, in general, are sparse. A 2004 EPA study on CBM 7 finds one paper Palmer et at., 1991, that has specific flowback values dating back t o 1991. Fortunately, the EPA does a literature review, which corroborates the validity of data from that study. We concluded the values from that paper will suffice for our analysis due to low data availability. The flowback rate was calculated for a du ration of 19 days, generating a recovery rate of 61% 33 The 19 day value is related to the injection durati on of the fracking fluids, in the residence time calculation in Section 2 5 Calculating resi dence time The flowback rate depends on the duration the fluid is recovered a higher duration will yield a hig her flowback rate

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14 and Palmer et al. states that flowback recovery rates were predicted to be as high as 82% for longer recovery periods We assumed the injection duration and the recovery duration to be the same, but the study differentiates the two. A n injection duration of 14 days, which is on par with our assumed injection duration for the wells in Weld County, if applied to CBM wells, would have a lower flowback volume. Ideally we would calculate the flowback fraction based on 14 days, but there we re not sufficient data points to extrapolate a flowback ratio for a 14 day injection duration. Our residence time calculation does take into account the duration of injection, but the limited data is the main crux to our calculations. 2 5 Calculating resi dence time Residence time refers to the average duration that a chemical is likely to remain in the storage ponds until it is removed. The residence time is assumed to be constant for all chemicals in the same pond. It is used to determine how long the chemicals are i n contact with the environment; the longer a chemical is in the environment the greater its potential impact. Additionally, it was assumed that the pits were always full implying that the flow rate entering the pit equals the flow rate leaving the pit. Companies will want to maximize their profits, and a pit that is not filled to capacity was not minimizing its expenses thereby reducing the profits. This assumption simplified the calculations. The general residence time formula is governed by the flow rate out of the pit, which is further reduced to four separate flow rates: evaporation, percolation, truck removal, and pipeline removal. Determining these flow rates required data that was either difficult to get, required too many assumptio ns or did not exist. Since the flow rates in and out were assumed to be equal, we could rely solely on the flow rate into the pit. Information regarding the disposal pits is required for generating the residence time. Data for pits in each county with s ufficient production and volume information were extracted. The

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15 length, width, and depth were used to determine volumes which was the key piece of information required from the pits. Calculating residence time ( requir e d [ 1 ] the volume of the storage pits discussed in ; [ 2 ] the duration of that injection discussed in 2 .3 Determining the duration of the injection phase ; [ 3 ] the fraction of the hydraulic fracturing fluid that returned to the surface discussed in 2 4 Determining f lowback fraction ; and [4] the injection volume of the hydraulic fracturing fluid Equation 14 a shows the flow rate in based residence time formula, which is the ideal equation to use but information on operations and specific data was not available The variables in the equation, which should be used when all the data f or the flow rate out of the pit, represent s the average capacity of the trucks that take away the used fracking fluid and the rate constant Equation 14 b sho w the flow rate out based residence time for mula used for our calculation o f residence time ( 14 a) (14 b) Table 2 shows the specific variables from Equation 14b that were used for the calculation of residence time. The largest sources of variability came from the injection duration and the flowback fraction especially for Las Animas County Residence time is proportional to the pit volume and injection d uration and is inversely proportional to the flowback fraction and the hydraulic fracturing fluid volume

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16 Table 2 Residence times and assumptions by county Weld County Las Animas County 2775.0 3 389.95 14 19 0.175 0.61 7332.79 295.09 30.3 41.2 2 6 Calculating aqueous based and evaporative m ass es For calculating environmental impact, it is important to know which the fraction of e ach chemical that ends up in each compartment. Traditional environmental engineering dictates the use of a two film model to determine the rate at which each volatilizes into the air, the mass that remains in the pit, and the mass that absorbs into the so il This calculation requires computing or determining: the concentrations in the air, water, and soil compartments; the gas and liquid phase mass transfer coefficient s; the air water partition coefficient ; the thickness of the film on the surface of the pond; and the diffusion coefficients of each chemical in the air and water phases. Each variable requires other input variables augmenting the complexity of the calculations. With greater complexity propagation of errors could start to become a potential problem; with more input variables and assumptions, data accuracy and multiple unknowns could affect the precision of the final values With 18 4 chemicals these calculations can take a lot of time, effort and the calculations lend themselves to generatin g too many errors from low precision and unknowns It was decided to try and simplify this process. In Correlation of Chemical Evaporation Rate with Vapor Pressure a simple and appro priate method to calculate the mass that evaporates from liquid pools was found. Equation 15 a shows the original equation from the paper 34 Equation 15 b

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17 is equivalent to Equation 15a but with the coefficient altered to reflect the appropriate units. (15a) (15b) At this point the equations differ by county due to the differences in the average disposal pits used within each county. F rom data extrac ted from the Colorado Oil and Gas Conservation Commission (COGCC) website 35 we found that the average surface area for stora ge p its in Weld County (designated by subscript W) i s 1041.2 m 2 and is 212. 2 m 2 for Las Animas County (designated by subscript LA) The surface area was found by dividing the volume of the pits by their depth, which were both readily available. From Section 2 5 Calculating resi dence time we know that the residences times are 30.3 and 41.2 days for Weld County and Las Animas County respectively, shown in Table 3 Table 3 County specific variables for calculating the evaporative mass per chemical Weld County Las Animas County 1041.2 212.2 30.3 41.2 chemical dependent chemical dependent Equation 15c is the generic equation that can be applied to any chemical in any location. Inserting the values from Table 3 into Equatio n 15c generates the county specific formulae in Equation 15d and Equation 15e where subscript denotes the county. Time is assumed to be the residence time for the injection phase, since all the chemicals being assessed are injected and most comes out i n that time.

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18 Units are important as the coefficients are unit dependent: vapor pressure is in pascals ; molecular weight is in grams per mole ; surface area is in meters squared ; and residence time is in days. (15c) (15d) (15e) Equation 15d and Equation 15e were then applied to each chemical for their respective counties to calculate the mass of a given chemical that volatilizes into the atmosphere. Once evaporative masses were found for each chemical (designated by subscript x) that value was subtracted from the entire mass that f lowed out of the pit the pit to find the chemical mass that remained in the pit shown in Equation 16 and Equ ation 16b for their respective counties (16a) (16b)

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19 3 Functional Unit A typical hydraulically fractu red well will have a base fl uid ( water 93% of the time 3 ) proppant, and at least a dozen chemicals. Exact chemicals and quantiti es of each vary greatly between individual wells depending on specific features of the local geology, depth of the deposit, and a host of other minor factors. The chemicals are delineated between functional categories to serve the various function require d by the geology. Additionally, the composition of the injection fluids for regular oil and gas wells will differ from coal bed methane (CBM) wells in various ways, analyzed in section three. In order to facilitated a comparative analysis between traditi onal oil and gas wells and CBM wells a functional unit is required. Since the goal of these wells is to produce a fuel, the chos en functional unit was the mega joule (MJ). Wells in Weld County, produced oil and gas, but wells in Las Animas county only pro duced gas. All volumes of oil and gas were converted to their energy equivalents in terms of MJ. From here each well could be reduced to MJ output. The environmental impact from chemicals and produced water generated were divided by the total energy, or total projected energy, produced from the wells. The environmental impact from chemicals had their own functional units. Their masses were multiplied by their endpoint ecotoxicity characterization factors to determine their base impact in units of which USEtox reduces to comparative toxicity units The summation of all chemical impacts over the quantity of wells yields the total impact. Finally, this impact was divided by the average energy output of the wells in e ach county to ascertain the comparative impact per MJ. The impact per unit energy would show which source was better for the env ironment in terms of chemicals.

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20 4 Hydraulic Fracturing Fluid Analysis 4 .1 Traditio nal o il & g a s w ells in Weld County This analysis focuses on the chemicals, which range from 14 to 51 separate chemicals per well according to our findings These functions are grouped into about 18 categories of which a chemical could fall into multiple categories but generally does not. Of the 184 chemicals we identified only 24 chemicals were used in multiple groups, while t he rest only had one function. The base fluid is used to suspend the chemicals and the proppant which hold s open the fractures i n the rock to facilitate the flow of oil and gas to the surface. Acids help dissolve rock and initiate cracks to start the oil and gas production. Corrosion inhibitors protects the pipe from corroding due to other chemicals in the fluid. Crosslinkers in crease viscosity as temperature increases and assist with proppant transport downhole. Biocides kill bacteria which can corrode and damage the pipe. Breakers delay the breakdown of gels when needed, reverse crosslinking, reduce viscosity, and remove poly mers from new fractures to more easily allow the production gas to flow. Crosslinkers and breakers worked against each other, but depending on phase of the well different properties are desired in the fluid. Friction reducers help to increase the fluid f low rate, increasing pump efficiency. Gels thicken water to suspend the proppant and increases the viscosity of the entire fluid. Iron controllers prevent precipitation of iron oxide compounds. Surfactants reduce surface tension of the fluid and improve the fluid recovery once the hydraulic fracturing phase is complete. pH reducing agents/buffers maintain the effectiveness of other chemical categories, specifically crosslinkers. Clay/shale stabilizers/controllers prevent the clay/shale from swelling int o the fluid and coming to the surface and/or reducing the efficiency of the entire process. Most of these categories are used for every HF job, but not necessarily 20 36

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21 The categories we identified are not verbatim the exact categories listed on fracfocus.org and other sources, due to semantics employed by the se vario us sources, but the functions remain the same. Fluids for each well differ by chemicals, chemical masses, categories due to chemical availability, geological formation, and other related factors. The average fluid of the 40 oil and gas wells in Weld Coun ty can be seen in Table 4 Average hydraulic fracturing fluid for a sample set of 40 traditional oil and gas wells in Weld County Table 4 which is corroborated by the values mentioned in the literature. The chemicals by mass, represent 1.065% of the total mass of the hydro fracking fluid. Table 4 Average hydraulic fracturing fluid for a sample set of 40 traditional oil and gas wells in Weld County CAT EGORY MASS, TOTAL (KG) MASS, AVERAGE PER WELL (KG) MASS, TOTAL (%) BASE FLUID 293,271,739 7,331,793.5 92.436% PROPPANT 20,618,054 515,451.3 6.499% FRICTION REDUCER 1,004,824 25,120.6 0.317% GEL 947,943 23,698.6 0.299% ACID/SOLVENT 383,821 9,595.5 0.12 1% BUFFER 200,912 5,022.8 0.063% SURFACTANT 153,485 3,837.1 0.048% CLAY STABILIZER 141,192 3,529.8 0.045% BREAKER 140,926 3,523.1 0.044% ADDITIVE 108,856 2,721.4 0.034% CROSSLINKER 100,564 2,514.1 0.032% PROPRIETARY OR UNKNO WN 69,448 1,736.2 0.022% EMULSIFIER 48,033 1,200.8 0.015% BIOCIDE 30,464 761.6 0.010% CORROSION INHIBITOR 23,442 586.1 0.007% ACTIVATOR 18,349 458.7 0.006% CONCENTRATE 5,264 131.6 0.002% NON EMULSIFIER 2,066 51.6 0.001% IRON CONTROL 256 6.4 <0.001 % There is a wide range o f chemicals used in the hydraulic fracturing phase including acids, alcohols, and aromatic hydrocarbons, which is not an exhaustive list, that are known carcinogens (cancer causing among humans) and environmental contaminants exhibiting high ecotoxicity va lues Additionally, a large selection of the detected chemicals has ecosystem or human health effects that

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22 are completely unknown because the chemicals have never been empirically studied; many of those chemicals have at least some physio chemical propert ies that are also unknown. This implies that the chemicals being injected underground are unstudied and not analyzed for da nger prior to being used. T he majority of t he HF fluid remains underground; little research is done on the impact of chemicals that remain underground, and they are also outside of the scope of this assessment. The fraction of fluid that does not come to the surface various by geological formation, but common figures range from 5 to 75% of that which is initially injected that returns ; the DJ Basin recovers between 8 and 27% 3 The explosive growth of HF has brought hundreds of chemic als to commercial use that were previously rarely used, if at all. These chemicals require research into their impact on the ecosystem and human health. We identified 184 chemicals used in only 5 0 wells (there are over 30,000 wells in Weld County alone) 5 of which only a quarter have had complete assessments undertaken; the remaining chemicals have n ot been extensively studied. 4 2 Coal b ed m ethane w ells in L as Animas County The average hydraulic fracturing fluid for coal bed methane wells differ noticeably from those of traditional oil and gas wells. The main differences are the inclusion of the foa ming category and the relatively smaller contributions from the base fluid and chemicals. The foaming agent could be either a carbon dioxide or nitrogen based foam, with negligible other chemicals. In the case of Las Animas County all wells employed a n itrogen foaming agent, which constituted 99.74% of all the chemicals by mass in the foam category. Table 5 Average hydraulic fracturing for a sample set of 10 coal bed methane wells in Las Animas, County CATEGORY MASS, TOTAL (KG) MA SS, AVERAGE (KG) MASS, TOTAL (%) BASE FLUID 2,950,906.554 295,090.655 60.27667% PROPPANT 1,223,623.485 122,362.348 24.99434% FOAMING AGENT 712,914.388 16,579.404 14.56234% GEL 4,457.891 445.789 0.09106% ACID 2,949.507 226.885 0.06025%

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23 CATEGORY MASS, TOTAL (KG) MA SS, AVERAGE (KG) MASS, TOTAL (%) PROPRIETARY OR UNKNOWN 563.149 33.126 0.01150% BREAKER 176.921 7.372 0.00361% CORROSION INHIBITOR 4.384 0.548 0.00009% SCALE INHIBITOR 3.306 0.301 0.00007% IRON CONTROL 3.262 1.631 0.00007%

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24 5 Oil, G as, and Water P roduction W ith the condition that they were alread y hydraulically fractured, w ells were chosen at random, which meant that they were at various stages of production. Of the wells in Weld County, nine (22.5%) of the 40 were completed, while the remainder were currently producing. Las Animas County had on ly one (10.0%) well that was no longer producing of the 10. Production data was extracted for all wells between the years of 1999 and 2015, inclusive ly 5 .1 P rojection model The 50 wells used for this paper are at various levels of production: some are n o longer producing; some have just begun to produce; and one well was refractured. Incomplete wells needed to have the lifetime production estimated to increase the accuracy of the assessment In order to do this our procedure began with standardizing the annual production by production year not actual calendar year. Regardless of the year a well began producing year (PY) 1 for each well was the first year it began producing. For example, the well with API designation 05 71 08280 began producing in 2005, and the well with API designation 05 71 09885 began producing in 2012 They will both have their production data for 2005 and 2012, respectively, begin in the same column, production year 1. Once the data was organized by production year, we found the a verage growth per production year was found by dividing the averaging available data from the previous year by the average available data for the current year. This growth rate was applied to each year with missing data, thereby filling the data gaps. Th e lifetime of each well was assumed to be the lifetime of the longest producing well in the data 1 7 years for Weld County and 11 years for Las Animas County. The following charts will show the total output, while the supplementary data will show all the data. The Model Reliance

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25 well came from the data and not from the projections. Values in red are derived from the model; all others are from the data. 5.2 Energy p roduced by s ource 5 .2 .1 Weld County Table 6 Well API Natural Gas Oil Total Total, Emp irical Total, Model Model Reliance Total, Emp irical Total, Model Model Reliance 12459 558.597E+6 558.597E+6 0.0% 143.526E+6 143.526E+6 0.0% 7.02E+08 12629 215.020E+6 215.020E+6 0.0% 104.934E+6 104.934E+6 0.0% 3.20E+08 19794 199.915E+6 204.445E+6 2.2% 256.493 E+6 258.832E+6 0.9% 4.63E+08 20613 72.478E+6 110.830E+6 34.6% 118.730E+6 147.489E+6 19.5% 2.58E+08 21028 379.533E+6 426.617E+6 11.0% 91.811E+6 115.059E+6 20.2% 5.42E+08 21514 150.285E+6 251.671E+6 40.3% 78.346E+6 103.228E+6 24.1% 3.55E+08 24914 189.506 E+6 190.495E+6 0.5% 161.335E+6 161.440E+6 0.1% 3.52E+08 25988 110.400E+6 118.475E+6 6.8% 110.410E+6 111.769E+6 1.2% 2.30E+08 29021 74.581E+6 204.070E+6 63.5% 99.495E+6 252.167E+6 60.5% 4.56E+08 29022 63.050E+6 157.910E+6 60.1% 79.294E+6 172.670E+6 54.1% 3.31E+08 30906 4.628E+6 10.117E+6 54.3% 20.207E+6 34.072E+6 40.7% 4.42E+07 31642 103.731E+6 205.561E+6 49.5% 410.744E+6 736.471E+6 44.2% 9.42E+08 32368 21.656E+6 93.059E+6 76.7% 307.602E+6 465.909E+6 34.0% 5.59E+08 32457 161.579E+6 388.886E+6 58.5% 36 5.410E+6 703.404E+6 48.1% 1.09E+09 32795 92.187E+6 313.080E+6 70.6% 69.053E+6 162.013E+6 57.4% 4.75E+08 33361 133.826E+6 436.662E+6 69.4% 323.203E+6 687.864E+6 53.0% 1.12E+09 34060 123.556E+6 379.899E+6 67.5% 33.905E+6 117.415E+6 71.1% 4.97E+08 34062 9 7.856E+6 277.620E+6 64.8% 129.186E+6 208.004E+6 37.9% 4.86E+08 34066 86.789E+6 285.815E+6 69.6% 26.234E+6 71.809E+6 63.5% 3.58E+08 34068 99.381E+6 291.256E+6 65.9% 37.760E+6 94.863E+6 60.2% 3.86E+08 34509 76.525E+6 274.293E+6 72.1% 79.618E+6 179.884E+6 55.7% 4.54E+08 36279 147.655E+6 400.241E+6 63.1% 290.594E+6 420.949E+6 31.0% 8.21E+08 36468 93.574E+6 248.438E+6 62.3% 239.736E+6 358.444E+6 33.1% 6.07E+08 36853 497.120E+6 1.885E+9 73.6% 598.875E+6 962.191E+6 37.8% 2.85E+09 36855 455.698E+6 1.470E+9 6 9.0% 786.279E+6 1.307E+9 39.9% 2.78E+09 36856 336.630E+6 1.028E+9 67.3% 596.202E+6 1.031E+9 42.2% 2.06E+09 37401 127.077E+6 359.218E+6 64.6% 381.604E+6 712.523E+6 46.4% 1.07E+09 37728 238.715E+6 778.178E+6 69.3% 530.612E+6 937.102E+6 43.4% 1.72E+09 377 90 100.476E+6 287.224E+6 65.0% 294.497E+6 460.504E+6 36.0% 7.48E+08 38169 85.260E+6 264.176E+6 67.7% 321.618E+6 523.673E+6 38.6% 7.88E+08 38415 335.736E+6 1.130E+9 70.3% 630.780E+6 1.015E+9 37.9% 2.15E+09

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26 Well API Natural Gas Oil Total Total, Emp irical Total, Model Model Reliance Total, Emp irical Total, Model Model Reliance 38416 610.800E+6 2.456E+9 75.1% 1.186E+9 2.217E+ 9 46.5% 4.67E+09 39006 169.136E+6 489.230E+6 65.4% 347.179E+6 530.227E+6 34.5% 1.02E+09 39008 182.190E+6 608.387E+6 70.1% 313.524E+6 522.001E+6 39.9% 1.13E+09 39009 176.609E+6 477.886E+6 63.0% 315.512E+6 490.432E+6 35.7% 9.68E+08 39010 146.611E+6 431.7 88E+6 66.0% 262.005E+6 428.621E+6 38.9% 8.60E+08 39088 52.197E+6 499.597E+6 89.6% 151.816E+6 556.777E+6 72.7% 1.06E+09 39603 192.787E+6 1.845E+9 89.6% 187.128E+6 686.284E+6 72.7% 2.53E+09 40388 125.738E+6 1.203E+9 89.6% 141.892E+6 520.384E+6 72.7% 1.72E +09 40503 83.665E+6 800.784E+6 89.6% 170.127E+6 623.931E+6 72.7% 1.42E+09 Empirical Average 1.793E+08 269.831E+6 1.03E+09 Total 1.079E+10 10.793E+9 4.14E+10 Average Annual Change 107.98% 94.11% Model Average 5.514E+08 483.432E+6 1,034,841,937 Total 2.206E+10 19.337E+9 41,393,677,463 Average Annual Change 109.60% 95.03% Average Model Reliance 5 .2.2 Las Animas County Table 7 Total natural gas production per well in Las Animas County Well API Total, Emp irical Total, Model Model Reliance 08280 1.3E+9 1.3E+9 0.0% 08908 416.8E+6 493.4E+6 15.5% 09386 229.2E+6 417.8E+6 45.1% 09490 126.4E+6 703.1E+6 82.0% 09782 15.9E+6 52.1E+6 69.5% 09871 459.6E+6 2.4E+9 80.5% 09874 596.0E+6 3.5E+9 82.9% 09878 59.5E+6 195.3E+6 69.5% 09885 457.5E+6 1.2E+9 61.0% 09898 1.1E+9 4.7E+9 75.8% Empirical Average 484.7E+6 Total 4.8E+9 Average Annual Change 138.4% Model Average 1,493,937,492 Total 14,939,374,916 Average Annual Change 140.0% Average Model Reliance 67.56%

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27 5.3 Produced water analysis 5.3 .1 Weld County Table 8 Total produced water generated in gallons per well in Weld County Well API Total, Emp irical Total, Model Model Reliance 12459 374. 850E+3 374.850E+3 0.0% 12629 239.274E+3 239.274E+3 0.0% 19794 11.718E+3 55.993E+3 79.1% 20613 112.476E+3 179.921E+3 37.5% 21028 347.130E+3 491.858E+3 29.4% 21514 140.364E+3 185.039E+3 24.1% 24914 42.294E+3 42.294E+3 0.0% 25988 52.416E+3 226.6 70E+3 76.9% 29021 35.574E+3 93.391E+3 61.9% 29022 45.570E+3 45.570E+3 0.0% 30906 11.760E+3 153.587E+3 92.3% 31642 2.122E+6 4.328E+6 51.0% 32368 1.519E+6 2.063E+6 26.4% 32457 781.158E+3 2.593E+6 69.9% 32795 83.622E+3 118.247E+3 29.3% 33361 4 80.354E+3 1.106E+6 56.6% 34060 80.304E+3 221.529E+3 63.8% 34062 388.122E+3 437.196E+3 11.2% 34066 78.498E+3 171.194E+3 54.1% 34068 143.976E+3 214.861E+3 33.0% 34509 247.968E+3 342.300E+3 27.6% 36279 517.482E+3 628.387E+3 17.6% 36468 861.294E+ 3 1.565E+6 45.0% 36853 2.881E+6 3.341E+6 13.8% 36855 3.820E+6 4.453E+6 14.2% 36856 2.990E+6 3.498E+6 14.5% 37401 1.297E+6 2.110E+6 38.6% 37728 966.840E+3 1.278E+6 24.4% 37790 422.730E+3 483.025E+3 12.5% 38169 473.424E+3 551.632E+3 14.2% 384 15 91.728E+3 154.808E+3 40.7% 38416 140.238E+3 234.173E+3 40.1% 39006 1.025E+6 1.309E+6 21.7% 39008 1.116E+6 1.418E+6 21.3%

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28 Well API Total, Emp irical Total, Model Model Reliance 39009 1.017E+6 1.278E+6 20.4% 39010 922.026E+3 1.173E+6 21.4% 39088 1.044E+6 2.968E+6 64.8% 39603 865.998E+3 2.462E+6 64.8% 40388 717.444E+3 2.040E+6 64.8% 40503 517.818E+3 1.472E+6 64.8% Empirical Average 725.630E+3 Total 29.025E+6 Average Annual Change 100.52% Model Average 1,152,521 Total 46,100,851 Average Annual Change 102.38% Average Mod el Reliance 37.04% 5.3.2 Las Animas County Table 9 Total produced water generated in gallons per well in Las Animas County Well API Total, Emp irical Total, Model Model Reliance 08280 8,305,080 8,305,080 0.0% 08908 12,221,244 13,334,379 8.3% 09386 51,169,650 51,391,546 0.4% 09490 50,002,386 52,106,716 4.0% 09782 17,527,440 17,527,440 0.0% 09871 5,439,588 12,173,292 55.3% 09874 5,173,140 13,870,217 62.7% 09878 1,281,042 2,315,005 44.7% 09885 567,336 786,336 27.9% 09898 34,202,700 75,383,558 54.6% Empirical Average 18,588,961 Total 185,889,606 Average Annual Change 107.9% Model Average 24,719,357 Total 247,193,569 Average Annual Change 102.3% Average Model Reliance 24.80% Coal bed m ethane wells produced only natural gas, but output 44.4% more energy than regular oil and gas wells. This could be due to any number of factors: CBM wells in our study relied

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29 on the model more than oil and gas wells possibly skewing CBM wells to a higher output; technical difficulties in capturing both oil and gas versus just capturing gas; or the shallower depth in CBM wells might reduce the amount of gas lost as it comes to the surface. Regardless of the reason, the relatively significant difference wil l have implications when assessing their comparative wells will reduced the overall impact generated by their chemicals

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30 6 Results and Discussion The res ult depicted were for our specific case, but the most influential aspect of the environmental impact resulted from the large variability the flowback fractions for each well. This fraction was responsible for governing the range of environmental impacts The flowback fraction was highly variable even between similar wells sharing a geological formation, and values were left up to low resolution data or only one data point and assumptions S hale flowback fraction was accurate only for the entire Niobrara shale as a whole not each well, and CBM wells had only on e value to use. The flowback fraction is functionally proportional to environmental impact, so a doubling in flowback would double the environmental impact. The differences in flowback fraction 1 7.5% for shale and 61% for CBM was deemed to be largely responsible for the environmental impact from CBM being 12.6% larger than shale. Our hypothesis going in to this research was the other way around, with shale having a larger impact than CBM. If t he flowback fractions were the same for shale and CBM than shale would indeed have a larger impact. Increasing the flowback fraction for shale to 19.7% or reducing it to 54.2% for CBM, while leaving the other flowback value constant would equate the two i mpacts. Both of these values are within the possible ranges of values, telling us that the shale and CBM are similar in terms of environmental impact for chemicals relative to the functional output. An assessment on the environmental impact of the other phases of the life cycle are needed to determine the overall impacts for the entire operation. 6.1 Energy and produced water comparison The literature states that coal bed methane wells will generate much higher quantities of produced water compared to reg ular oil and gas wells employing hydraulic fracturing 37 Once the average energy and produced water output per well for Weld Co unty and Las Animas were

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31 average produced water ( gallons) per unit energy (MJ). Weld County averaged 1,152,521 and Las Animas averaged 24,719,357 gallons per well o f produced water a ratio of 21.5 times more produced water was generated for CBM wells than regular oil and gas wells. Weld County wells generated an average of 1,034,841,937 MJ of energy; Las Animas wells generated 1,493 937,492, a ratio of 1. 44 greater The se findings were on par with the literature Weld County has a rate o f 0.0011 gal/MJ compared to 0.0165 gal/MJ for Las Animas. Las Animas generates 14 .9 times more produced water for the same energy output. 6 .2 Categorization f actors Of the 18 4 ch emicals detected and analyzed, categorization factors (CFs) were generated for 128, with the remaining 56 chemicals having no factors generated. These 56 chemicals included the subset of 33 chemicals that had no CAS number, were ambiguously named, had gen eric names, were proprietary, or were just identified by their category (i.e. surfactant), so we knew we would There were 36 inorganics chemicals, as well, for which USEtox is not specifically design ed. F or inorganic compounds, many chemical properties are assumed to be a specific value vapor pressure the degradation rates in air, water, sediment, and soil are all Many of the p roperties used within USEtox have equations that can be further used to estimate other properties. Once these equations are applie d most of the required properties are known; the only exception is the octanol water coefficient, which is the main physio chemical property used to estimate most other properties. Inorganic compounds relied heavily on experimental data because EPI Suite cannot be applied to inorganic compounds with any accuracy. USEtox requires a certain set of chemical properties to generate the Section 2 .2.1 Physio chemical properties r equired for USEtox so if any one of these chemicals property data is missing no factors are able to be created. The remaining 23

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32 s should be able to be generated for these 56 chemicals. In most cases the octanol water or vapor pressure were missing since they are fundamental properties and cannot be calculated or estimated within USEtox. If their empirical values could not be found or predicted via modeling software than there were relatively few options to f inding a viable value. were generated using the North American landscape, with a OECD countries average household indoor environment with Industry, OECD as the industrial indoor environment. Table 10 shows a ll the categorization factors for every chemical assessed.

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33 Table 10 Raw categorization factors for ecotoxicity Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Average of all known chemicals 1.98E+04 2.21E+04 2.36E+04 1.61E+04 6.08E+05 2.09E+02 4.30E+03 4.30E+03 3rd Party Additive n/a n/a n/a n/a n/a n/a n/a n/a 1 (benzyl)quinolinium chloride 15619 48 4 4.41E 02 4.41E 02 4.41E 02 4.41E 02 1.30E 01 3.12E 10 6.52E 02 6.52E 02 1,2,3 trimethylbenzene 526 73 8 4.02E+02 4.26E+02 4.42E+02 3.62E+02 7.03E+03 1.47E+02 3.29E+02 3.29E+02 1,2,4 trimethyl benzene 95 63 6 5.03E+01 5.33E+01 5.53E+01 4.54E+01 8.73E+02 1.83E+01 4.16E+01 4.16E+01 2,2 dibromo 3 nitrilopropionamide 10222 01 2 5.08E+03 5.09E+03 5.10E+03 5.07E+03 1.71E+04 5.31E 02 7.43E+03 7.43E+03 2,3 Dihydroxypropyl trimethylammonium chloride 34 004 36 0 6.47E 03 6.48E 03 6.49E 03 6.45E 03 2.22E 02 1.85E 16 9.33E 03 9.33E 03 2 amine 2 methyl propanol 124 68 5 1.43E+00 1.60E+00 1.71E+00 1.16E+00 4.48E+01 7.91E 06 2.16E 01 2.16E 01 2 bromo 3 nitrilopropionamide 1113 55 9 6.19E 01 6.20E 01 6.21E 01 6.16E 01 2.21E+00 2.28E 09 9.00E 01 9.00E 01 2 butoxyethanol 111 76 2 8.48E 01 8.57E 01 8.63E 01 8.32E 01 4.81E+00 1.69E 06 1.14E+00 1.14E+00 2 ethylhexanol 104 76 7 2.82E+01 2.89E+01 2.93E+01 2.71E+01 2.50E+02 9.96E 01 3.48E+01 3.48E+01 3,4,4 trimethy loxazolidine 75673 43 7 2.94E+02 2.95E+02 2.96E+02 2.93E+02 1.09E+03 4.82E+00 4.34E+02 4.34E+02 3 chloro 2 hydroxypropyl trimethylazanium;chloride 3327 22 8 1.15E+02 1.15E+02 1.15E+02 1.15E+02 3.95E+02 3.06E 11 1.66E+02 1.66E+02 4,4 dimethyloxazolidine 5 1200 87 4 5.24E+00 5.86E+00 6.26E+00 4.22E+00 1.65E+02 8.41E 03 7.39E 01 8.43E 01 4 nonylphenyl 127087 87 0 4.07E+04 4.21E+04 4.30E+04 3.84E+04 4.59E+05 3.24E 06 4.54E+04 4.54E+04 Acetic acid 64 19 7 9.91E 01 1.09E+00 1.15E+00 8.27E 01 2.68E+01 2.53E 05 3.37E 01 3.37E 01 Acetic anhydride 108 24 7 6.57E+00 6.60E+00 6.62E+00 6.53E+00 2.64E+01 1.18E 01 9.54E+00 9.54E+00 Alcohol amine 2.28E+00 2.29E+00 2.29E+00 2.27E+00 8.07E+00 4.88E 09 3.28E+00 3.28E+00 Aldehyde 2.79E+02 2.80E+02 2.81E+02 2.77E+02 1.07 E+03 4.81E 06 3.98E+02 3.98E+02 Alkoxylated amine 1.25E+06 1.41E+06 1.52E+06 9.72E+05 4.35E+07 7.01E 05 8.72E+03 8.72E+03 Alkyl amine surfactant n/a n/a n/a n/a n/a n/a n/a n/a Alkyl dimethyl benzyl ammonium chloride 68424 85 1 1.01E+02 1.09E+02 1.14E +02 8.80E+01 2.19E+03 6.18E 06 6.22E+01 6.22E+01 Alkyl pyridine benzyl quaternary ammonium chloride 68909 18 2 5.73E 02 5.73E 02 5.73E 02 5.73E 02 1.71E 01 1.39E 10 8.46E 02 8.46E 02

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34 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Alkylene oxide block polymer n/a n/a n/a n/a n/a n/a n/a n/a Aluminum oxide 1344 28 1 n/a n/a n/a n/a n/a n/a n/a n/a Amide 1.11E+02 1.22E+02 1.29E+02 9.38E+01 2.88E+03 2.04E 02 4.48E+01 4.48E+01 Amine salts n/a n/a n/a n/a n/a n/a n/a n/a Amines, coco alkyl, ethoxylated 61791 14 8 1.34E+03 1.37E+03 1.40E+03 1.27E+03 1 .30E+04 2.94E 09 1.55E+03 1.55E+03 Amines, tallow alkyl, ethoxylated 61791 26 2 1.27E+02 1.41E+02 1.51E+02 1.02E+02 3.93E+03 1.28E 09 2.01E+01 2.01E+01 Ammonium acetate 631 61 8 5.34E+01 5.35E+01 5.36E+01 5.32E+01 1.89E+02 2.57E 06 7.68E+01 7.68E+01 Amm onium chloride 12125 02 9 3.03E+03 3.03E+03 3.02E+03 3.03E+03 8.33E+03 8.09E 12 4.80E+03 4.80E+03 Ammonium dihydrogen phosphate 7722 76 1 n/a n/a n/a n/a n/a n/a n/a n/a Ammonium hydroxide 1336 21 6 n/a n/a n/a n/a n/a n/a n/a n/a Ammonium persulfate 77 27 54 0 4.80E+02 4.80E+02 4.79E+02 4.81E+02 1.32E+03 7.88E 13 7.61E+02 7.61E+02 Ammonium phosphite 13446 12 3 1.07E+02 1.07E+02 1.07E+02 1.08E+02 2.96E+02 2.36E 13 1.70E+02 1.70E+02 Ammonium salt n/a n/a n/a n/a n/a n/a n/a n/a Amphoteric surfactant n /a n/a n/a n/a n/a n/a n/a n/a Antifoam n/a n/a n/a n/a n/a n/a n/a n/a Apatite 64476 38 6 n/a n/a n/a n/a n/a n/a n/a n/a Aromatic aldehyde 5.17E+01 5.27E+01 5.34E+01 4.99E+01 4.10E+02 3.28E+00 6.65E+01 6.65E+01 Bentonite, benzyl(hydrogenated tallow alkyl) dimethylammonium stearate complex 121888 68 4 n/a n/a n/a n/a n/a n/a n/a n/a Biotite 1302 27 8 n/a n/a n/a n/a n/a n/a n/a n/a Borate 7550 67 7 n/a n/a n/a n/a n/a n/a n/a n/a Calcite 471 34 1 n/a n/a n/a n/a n/a n/a n/a n/a Calcium chloride 1 0043 52 4 n/a n/a n/a n/a n/a n/a n/a n/a Carboxymethyl guar gum, sodium salt 39346 76 4 n/a n/a n/a n/a n/a n/a n/a n/a Chlorous acid, sodium salt 7758 19 2 1.00E 01 1.00E 01 1.00E 01 1.00E 01 2.76E 01 2.15E 16 1.59E 01 1.59E 01 Choline chloride 67 48 1 1.32E+00 1.34E+00 1.35E+00 1.29E+00 8.36E+00 3.61E 13 1.73E+00 1.73E+00

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35 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Cinnamaldehyde 104 55 2 5.47E+02 5.57E+02 5.63E+02 5.30E+02 4.06E+03 5.60E+00 7.03E+02 7.03E+02 Citric acid 77 92 9 1.64E+00 1.67E+00 1.69E+00 1.59E+00 1.17E+01 1.97E 13 2.09E+00 2 .09E+00 Clay n/a n/a n/a n/a n/a n/a n/a n/a Cobalt acetate 71 48 7 n/a n/a n/a n/a n/a n/a n/a n/a Crystalline silica, quartz 14808 60 7 n/a n/a n/a n/a n/a n/a n/a n/a Dibromoacetonitrile 3252 43 5 1.13E+01 1.14E+01 1.15E+01 1.12E+01 5.50E+01 9.65E 04 1.57E+01 1.57E+01 Didecyl dimethyl ammonium chloride 111 42 2 4.77E+00 5.24E+00 5.55E+00 4.00E+00 1.28E+02 2.77E 04 1.70E+00 1.70E+00 Diethylenetriamine 111 40 0 3.40E+00 3.58E+00 3.70E+00 3.09E+00 5.49E+01 5.87E 13 2.92E+00 2.92E+00 Dinonyphenyl 901 4 93 1 n/a n/a n/a n/a n/a n/a n/a n/a Disodium ethylene diaminediacetate 38011 25 5 8.02E 06 8.06E 06 8.08E 06 7.95E 06 3.37E 05 1.38E 18 1.13E 05 1.13E 05 EDTA/copper chelate 14025 15 1 2.75E+00 2.77E+00 2.78E+00 2.71E+00 1.37E+01 2.41E 22 3.78E+00 3.7 8E+00 Enzyme n/a n/a n/a n/a n/a n/a n/a n/a EO C7 9 iso, C8 rich alcohols 78330 19 5 3.36E+02 3.36E+02 3.37E+02 3.36E+02 1.08E+03 3.18E 08 4.94E+02 4.94E+02 EO C9 11 iso, C10 rich alcohols 78330 20 8 1.57E+01 1.71E+01 1.81E+01 1.33E+01 3.96E+02 2.78E+ 00 7.32E+00 7.32E+00 Ethanol 64 17 5 4.09E 01 4.12E 01 4.14E 01 4.04E 01 1.97E+00 4.98E 03 5.75E 01 5.75E 01 Ethoxylated alcohol 2.35E+02 2.36E+02 2.37E+02 2.33E+02 9.88E+02 9.45E 09 3.32E+02 3.32E+02 Ethoxylated amine 1.27E+02 1.41E+02 1.51E+02 1.02E +02 3.93E+03 1.28E 09 2.01E+01 2.01E+01 Ethoxylated branched C13 alcohol 78330 21 9 1.22E+02 1.33E+02 1.41E+02 1.02E+02 3.22E+03 1.87E+01 4.90E+01 4.90E+01 Ethoxylated decyl alcohol 2.61E+01 2.84E+01 2.99E+01 2.23E+01 6.35E+02 9.06E 10 1.23E+01 1.23E+01 Ethoxylated fatty acid 1.27E+02 1.41E+02 1.51E+02 1.02E+02 3.93E+03 1.28E 09 2.01E+01 2.01E+01 Ethylene glycol 107 21 1 1.84E 01 1.85E 01 1.85E 01 1.83E 01 7.44E 01 2.62E 05 2.60E 01 2.60E 01 Fatty acid tall oil amide 1.49E+04 1.67E+04 1.80E+04 1.18E +04 4.96E+05 2.46E+02 6.08E+02 6.08E+02 Fatty acids n/a n/a n/a n/a n/a n/a n/a n/a Fatty acids, tall oil 61790 12 3 1.49E+04 1.67E+04 1.80E+04 1.18E+04 4.96E+05 2.46E+02 6.08E+02 6.08E+02 Formaldehyde amine resin 56652 26 7 1.34E+01 1.40E+01 1.45E+01 1.24E+01 1.93E+02 1.43E 03 1.26E+01 1.26E+01

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36 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Formaldehyde;2 methyloxirane;(1E,3E) 4,5,5 trimethylhexa 1,3 dien 1 ol 29316 47 0 4.40E+02 4.48E+02 4.54E+02 4.27E+02 3.26E+03 4.46E 01 5.67E+02 5.67E+02 Formaldehyde;2 methyloxirane;4 nonylphenol;oxirane 6342 8 92 2 n/a n/a n/a n/a n/a n/a n/a n/a Formic acid 64 18 6 9.12E 01 1.00E+00 1.06E+00 7.66E 01 2.40E+01 4.83E 06 3.44E 01 3.44E 01 Glutaraldehyde 111 30 8 2.06E+02 2.10E+02 2.13E+02 1.99E+02 1.63E+03 3.22E 01 2.57E+02 2.57E+02 Glycerine 56 81 5 2.71E 02 2.72E 02 2.73E 02 2.69E 02 1.14E 01 9.76E 07 3.81E 02 3.81E 02 Goethite 1310 14 1 n/a n/a n/a n/a n/a n/a n/a n/a Guar gum 9000 30 0 3.67E+03 3.67E+03 3.67E+03 3.68E+03 1.04E+04 5.74E 35 5.50E+03 5.50E+03 Guar gum derivative 7.61E+00 7.60E+00 7.60E+00 7.62E+00 2.17E+01 7.37E 13 1.14E+01 1.14E+01 Haloalkyl heteropolycycle salt n/a n/a n/a n/a n/a n/a n/a n/a Heavy aliphatic petroleum naphtha solvent 64742 96 7 1.40E+00 1.52E+00 1.61E+00 1.19E+00 3.45E+01 9.48E 02 7.08E 01 7.08E 01 Heavy aromatic pet roleum naphtha 64742 94 5 3.09E+01 3.28E+01 3.41E+01 2.76E+01 5.70E+02 9.98E+00 2.39E+01 2.39E+01 Heavy hydrotreated petroleum naphtha 64742 48 9 1.26E+02 1.36E+02 1.43E+02 1.09E+02 2.80E+03 1.50E+01 7.80E+01 7.80E+01 Hexamethylenetetramine 100 97 0 1.69 E 01 1.70E 01 1.70E 01 1.67E 01 7.22E 01 1.36E 07 2.43E 01 2.43E 01 Hydrated magnesium silicate (talc) 14807 96 6 n/a n/a n/a n/a n/a n/a n/a n/a Hydrochloric acid 7641 01 0 2.83E+04 2.82E+04 2.82E+04 2.83E+04 7.78E+04 6.34E 11 4.48E+04 4.48E+04 Hydrotr eated light petroleum distillate 64742 47 8 3.80E+02 4.10E+02 4.31E+02 3.29E+02 8.59E+03 3.84E+01 2.29E+02 2.29E+02 Hydrotreated medium petroleum distillates 64742 46 7 1.13E+06 1.25E+06 1.33E+06 9.23E+05 3.31E+07 2.19E+04 3.22E+05 3.22E+05 Inorganic bas e n/a n/a n/a n/a n/a n/a n/a n/a Inorganic salt 3.99E+03 3.99E+03 3.99E+03 4.00E+03 1.10E+04 1.03E 11 6.33E+03 6.33E+03 Isopropanol 67 63 0 4.99E 02 5.26E 02 5.44E 02 4.55E 02 7.93E 01 1.19E 02 4.59E 02 4.59E 02 Isotridecanol, ethoxylated (TDA 6) 904 3 30 5 4.45E+01 4.53E+01 4.58E+01 4.31E+01 3.26E+02 1.58E 08 5.73E+01 5.73E+01 Lactic acid 50 21 5 2.43E 03 2.49E 03 2.52E 03 2.34E 03 2.07E 02 2.98E 10 2.94E 03 2.94E 03 Laury alcohol ethoxylate 68551 12 2 8.74E+02 9.64E+02 1.02E+03 7.24E+02 2.45E+04 1. 39E+02 2.88E+02 2.88E+02

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37 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Light aromatic petroleum naphtha solvent 64742 95 6 3.97E+01 4.22E+01 4.39E+01 3.55E+01 7.32E+02 1.28E+01 3.07E+01 3.07E+01 Magnesium oxide 1309 48 4 n/a n/a n/a n/a n/a n/a n/a n/a Magnesium peroxide 14452 57 4 n/a n/a n/a n/a n/a n/a n/a n/a Mesitylene 108 67 8 2.15E+01 2.28E+01 2.36E+01 1.95E+01 3.64E+02 7.86E+00 1.83E+01 1.83E+01 Methanol 67 56 1 3.31E 01 3.34E 01 3.36E 01 3.27E 01 1.67E+00 4.15E 03 4.63E 01 4.63E 01 Methyl isobutyl ketone 108 10 1 4.83E 01 5.03E 01 5.17E 01 4.48E 01 6.51E+00 7.08E 02 4.95E 01 4.95E 01 Naphthalene 91 20 3 2.07E+01 2.30E+01 2.46E+01 1.67E+01 6.39E+02 8.47E 01 3.77E+00 3.77E+00 Naphthenic acid ethoxylate 68410 62 8 6.36E+01 6.37E+01 6.38E+01 6.35E+01 2.12E+02 1.63E 08 9.39E+01 9.39E+01 N d imethyl formamide 68 12 2 4.89E 01 4.90E 01 4.91E 01 4.87E 01 1.77E+00 1.38E 04 7.03E 01 7.03E 01 Nitrilotriacetate, trisodium salt (NTA) 5064 31 3 1.23E 02 1.24E 02 1.24E 02 1.22E 02 5.59E 02 5.85E 18 1.71E 02 1.71E 02 Nitrogen 7727 37 9 4.87E+01 4.90E+ 01 4.91E+01 4.83E+01 2.03E+02 2.55E 20 6.88E+01 6.88E+01 No hazardous ingredients n/a n/a n/a n/a n/a n/a n/a n/a No MSDS ingredients (Friction Reducer) n/a n/a n/a n/a n/a n/a n/a n/a Nonhazardous n/a n/a n/a n/a n/a n/a n/a n/a Non ionic surfactan t n/a n/a n/a n/a n/a n/a n/a n/a N propanol zirconate n/a n/a n/a n/a n/a n/a n/a n/a N propyl zirconate 23519 77 9 n/a n/a n/a n/a n/a n/a n/a n/a Olefin 64743 02 8 3.26E+02 3.56E+02 3.77E+02 2.74E+02 8.46E+03 5.14E+01 1.42E+02 1.42E+02 Organic pol yol n/a n/a n/a n/a n/a n/a n/a n/a Organic sulfonic acid 27176 87 0 1.57E+02 1.63E+02 1.67E+02 1.47E+02 1.97E+03 1.50E 04 1.61E+02 1.61E+02 Organic sulfur compound n/a n/a n/a n/a n/a n/a n/a n/a Oxirane, 2 methyl polymer with oxirane, monodecyl et her 37251 67 5 4.21E+02 4.47E+02 4.64E+02 3.78E+02 7.57E+03 1.06E 02 3.26E+02 3.26E+02 Oxyalkylated fatty acid n/a n/a n/a n/a n/a n/a n/a n/a Phenol/formaldehyde resin 9003 35 4 1.34E+01 1.40E+01 1.45E+01 1.24E+01 1.93E+02 1.43E 03 1.26E+01 1.26E+01

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38 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil P oly(oxy 1,2 ethanediyl),.alpha. tetradecyl .omega. hydroxy 27306 79 2 4.50E+03 5.11E+03 5.51E+03 3.50E+03 1.61E+05 1.15E+01 1.13E+01 1.13E+01 Poly(tetrafluoroethylene) 9002 84 0 3.67E 01 3.87E 01 4.00E 01 3.34E 01 5.95E+00 7.95E 02 3.32E 01 3.32E 01 Poly acrylate 79 10 7 4.96E 01 4.99E 01 5.02E 01 4.89E 01 2.43E+00 4.15E 04 6.85E 01 6.85E 01 Polyether n/a n/a n/a n/a n/a n/a n/a n/a Polyethylene glycol 25322 68 3 2.11E+02 2.12E+02 2.12E+02 2.10E+02 7.26E+02 4.18E 09 3.04E+02 3.04E+02 Polyoxyalkylenes 6 8951 67 7 1.90E+03 2.10E+03 2.24E+03 1.55E+03 5.59E+04 1.97E+02 4.73E+02 4.73E+02 Polyoxyalkylenes surfactant n/a n/a n/a n/a n/a n/a n/a n/a Polyquaternary amine n/a n/a n/a n/a n/a n/a n/a n/a Polysaccharide 68130 15 4 2.07E 05 2.11E 05 2.14E 05 2.0 0E 05 1.62E 04 1.32E 32 2.56E 05 2.56E 05 Potassium carbonate 584 08 7 1.15E 02 1.15E 02 1.15E 02 1.15E 02 3.95E 02 1.08E 22 1.66E 02 1.66E 02 Potassium hydroxide 1310 58 3 7.61E 03 7.60E 03 7.60E 03 7.62E 03 2.09E 02 1.99E 17 1.21E 02 1.21E 02 Potassiu m persulfate 7727 21 1 1.45E+00 1.45E+00 1.45E+00 1.45E+00 3.99E+00 2.25E 15 2.30E+00 2.30E+00 Propanol 71 23 8 3.09E 01 3.14E 01 3.18E 01 3.00E 01 2.25E+00 8.14E 03 4.04E 01 4.04E 01 Propargyl alcohol 107 19 7 5.21E+02 5.25E+02 5.29E+02 5.13E+02 2.73E+0 3 2.43E+00 7.19E+02 7.19E+02 Proprietary component, biocide n/a n/a n/a n/a n/a n/a n/a n/a Proprietary component, surfactant n/a n/a n/a n/a n/a n/a n/a n/a Proprietary sesquiolate 8007 43 0 2.79E 02 2.75E 02 2.73E 02 2.84E 02 1.58E 03 2.07E 16 5.72E 08 5.72E 08 Propylene glycol 57 55 6 1.11E 01 1.11E 01 1.12E 01 1.10E 01 4.95E 01 3.21E 06 1.54E 01 1.54E 01 Quaternary amine n/a n/a n/a n/a n/a n/a n/a n/a Quaternary ammonium compound 122 18 9 4.20E+02 4.66E+02 4.96E+02 3.44E+02 1.24E+04 4.12E 05 1 .06E+02 1.06E+02 Quaternary ammonium compounds, bis(hydrogenated tallow alkyl)dimethyl, salts with montmorillonite 68911 87 5 n/a n/a n/a n/a n/a n/a n/a n/a Quaternary ammonium compounds, bis(hydrotreated tallow alkyl)dimethyl, salts with bentonite 6895 3 58 2 n/a n/a n/a n/a n/a n/a n/a n/a Quaternary ammonium salt 4.20E+02 4.66E+02 4.96E+02 3.44E+02 1.24E+04 4.12E 05 1.06E+02 1.06E+02

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39 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Silica, amorphous fumed 7631 86 9 1.59E+02 1.59E+02 1.59E+02 1.59E+02 4.37E+02 4.07E 13 2.52E+02 2.52E+02 Sodium b icarbonate 144 55 8 2.68E 02 2.68E 02 2.68E 02 2.67E 02 9.27E 02 5.54E 07 3.85E 02 3.88E 02 Sodium bromide 7647 15 6 1.45E+02 1.45E+02 1.45E+02 1.45E+02 3.99E+02 3.10E 13 2.30E+02 2.30E+02 Sodium chloride 7647 14 5 3.99E+03 3.99E+03 3.99E+03 4.00E+03 1.1 0E+04 1.03E 11 6.33E+03 6.33E+03 Sodium erythorbate 6381 77 7 1.27E+00 1.43E+00 1.54E+00 9.93E 01 4.40E+01 1.53E 21 5.88E 03 5.88E 03 Sodium hydroxide 1310 73 2 3.10E+04 3.10E+04 3.09E+04 3.10E+04 8.53E+04 9.09E 11 4.91E+04 4.91E+04 Sodium hydroxyacetat e 2836 32 0 7.49E 03 7.65E 03 7.76E 03 7.22E 03 6.12E 02 2.12E 08 9.19E 03 9.19E 03 Sodium hypochlorite 7681 52 9 1.03E+01 1.03E+01 1.02E+01 1.03E+01 2.82E+01 2.30E 14 1.63E+01 1.63E+01 Sodium iodide 7681 82 5 1.63E+02 1.63E+02 1.62E+02 1.63E+02 4.48E+02 3.07E 13 2.58E+02 2.58E+02 Sodium lactate 72 17 3 5.94E 02 5.97E 02 6.00E 02 5.89E 02 2.55E 01 1.31E 05 8.35E 02 8.35E 02 Sodium perborate tetrahydrate 10486 00 7 n/a n/a n/a n/a n/a n/a n/a n/a Sodium persulfate 7775 27 1 3.10E+00 3.10E+00 3.09E+00 3. 11E+00 8.53E+00 5.02E 15 4.91E+00 4.91E+00 Sodium sulfate 7757 82 6 3.73E+00 3.72E+00 3.72E+00 3.73E+00 1.03E+01 7.12E 15 5.90E+00 5.90E+00 Sodium;prop 2 enamide;prop 2 enoate;prop 2 enoic acid 62649 23 4 3.31E+03 3.32E+03 3.32E+03 3.29E+03 1.19E+04 5.03 E 06 4.75E+03 4.75E+03 Sorbitan monooleate polyoxyethylene derivative 9005 65 6 1.82E+04 1.82E+04 1.82E+04 1.83E+04 5.02E+04 2.25E 31 2.80E+04 2.80E+04 Sorbitan, mono 9 octadecenoate, (Z) 1338 43 8 3.56E+03 3.95E+03 4.22E+03 2.91E+03 1.06E+05 8.31E 06 7. 79E+02 7.79E+02 Soybean oil methyl ester 67784 80 9 4.18E+04 4.67E+04 4.99E+04 3.36E+04 1.31E+06 4.46E+03 6.54E+03 6.54E+03 Styrene acrylic copolymer 25085 34 1 6.10E+00 6.28E+00 6.40E+00 5.80E+00 6.26E+01 2.72E 04 6.93E+00 6.93E+00 Sucrose 57 50 1 1.33 E 02 1.33E 02 1.34E 02 1.32E 02 5.36E 02 1.35E 21 1.87E 02 1.87E 02 Surfactants 4.99E 02 5.26E 02 5.44E 02 4.55E 02 7.93E 01 1.19E 02 4.59E 02 4.59E 02 Tall oil acid diethanolamide 68155 20 4 3.04E+03 3.37E+03 3.59E+03 2.49E+03 8.92E+04 5.62E 05 7.19E+0 2 7.19E+02 Terpenes and terpenoids 68956 56 9 3.38E 01 3.71E 01 3.93E 01 2.83E 01 9.03E+00 2.25E 13 1.23E 01 1.23E 01 Terpenes and terpenoids, sweet orange oil 68647 72 3 2.34E+02 2.50E+02 2.61E+02 2.06E+02 4.74E+03 4.60E+01 1.65E+02 1.65E+02 Tert butyl hydroperoxide 75 91 2 3.83E+01 3.97E+01 4.06E+01 3.59E+01 4.57E+02 1.66E+00 4.19E+01 4.19E+01

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40 Chemical CAS Number Endpoint Ecotoxicity Charact erization F actor s [PDF.m 3 .day/kg emitted ] (freshwater) To Household Air To Industrial Air To Urban Air Continental Rural Air To Fresh Water To Sea Water To Natural Soil To Agricultural Soil Tetramethyl ammonium chloride 75 57 0 5.31E+00 5.34E+00 5.36E+00 5.26E+00 2.29E+01 3.07E 11 7.46E+00 7.46E+00 Tetrasodium ethylenediamine tetraacetate 64 02 8 n/a n/a n/a n/a n/a n/a n/a n/a Thiourea polymer 68527 49 1 5.79E 01 5.79E 01 5.79E 01 5.79E 01 1.71E+00 4.29E 08 8.56E 01 8.56E 01 Trade secret n/a n/a n/a n/a n/a n/a n/a n/a Triethanolamine 102 71 6 3.30E 01 3.59E 01 3.78E 01 2.83E 01 7.92E+00 3.31E 10 1.61E 01 1.79E 01 Triethanolamine zirconate 101033 44 7 n/a n/a n/a n/a n/a n/a n/a n/a Triethylene glycol 112 27 6 6.16E 02 6.18E 02 6.19E 02 6.14E 02 2.18E 01 4.83E 08 8.87E 02 8.87E 02 Triisopropanolamine 122 20 3 1.68E+00 1.81E+00 1.89E+00 1.47E +00 3.57E+01 1.21E 08 1.04E+00 1.14E+00 Trimethylamine 75 50 3 6.62E 01 8.13E 01 9.14E 01 4.10E 01 4.11E+01 1.83E 03 3.65E 02 3.66E 02 Trisodium ethylenediaminetriacetate 19019 43 3 3.42E 02 3.44E 02 3.45E 02 3.39E 02 1.44E 01 1.73E 18 4.80E 02 4.80E 02 Various oxides and trace elements (Fe2O3, CaO, and MgO) are the largest fractions n/a n/a n/a n/a n/a n/a n/a n/a Vinylidene chloride methyl acrylate copolymer 25038 72 6 1.53E+02 1.57E+02 1.60E+02 1.46E+02 1.46E+03 2.91E+01 1.85E+02 1.85E+02 Water 773 2 18 5 n/a n/a n/a n/a n/a n/a n/a n/a Xylene 1330 20 7 1.82E+01 1.95E+01 2.03E+01 1.62E+01 3.50E+02 3.78E+00 1.38E+01 1.38E+01 Zirconium complex n/a n/a n/a n/a n/a n/a n/a n/a Zirconium sodium hydroxy lactate complex 113184 20 6 n/a n/a n/a n/a n/a n /a n/a n/a Zirconium solution n/a n/a n/a n/a n/a n/a n/a n/a Zirconium, acetate lactate oxo ammonium complexes 68909 34 2 1.58E 02 1.58E 02 1.58E 02 1.58E 02 4.66E 02 7.14E 14 2.34E 02 2.34E 02

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41 The yellow and green colors in Table 10 match the chemicals that are not in either USEtox or TRACI as mentioned in Section 2 .1 Procedure for generating chemical cat egorization factors by data availability : yellow coincides t o chemicals that are completely unknown with categorization factors that could not be generated; green references chemicals that had a viable substitute chemical or the same chemical found under a similar name but could not be confirmed to be the same chem ical, although it was highly likely. 6. 3 Environmental impact assessment Since our assessment focused only on the chemical mass that evaporated into the air and the mass that remained within the disposal pit water, we required only the emissions to contin ental rural air and to fresh water. In order to calculate the impact, the categorization factors were applied to the evaporative mass and mass the remains in the disposal pit yielding PDF.m 3 .day (potentially d isappeared fraction of species integrated over the freshwater volume and the duration of one day 38 ). After finding the final impact per chemical for each county the average energy output was divided to d etermine the impact per unit of energy delivered for each county. For the chemicals lacking categorization factors we took the average CF for the known chemicals and applied it to the unknown chemicals. This methodology was required for 56 of the 184 chem icals representing 30.4% of all chemicals Chemicals without a flowback mass, not detected in their specific county, or combined with substitute chemicals were omitted from the following tables, since they had no impact. Any impacts for omitted chemicals were accountable in their respective alternative chemicals. Additionally, water and sand were removed from the impact assessment because they were the vast majority of mass for the fracking fluid, but had no impact and are inert. The models were unable to discern water and sand and would calculated an impact, skewing the results.

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42 Table 11 Environmental impact for Las Animas County by chemical Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ 1 (benzyl)quinolinium chl oride 15619 48 4 38.9 0.05 38.81 2.3E 3 1.7E+0 55.8E 15 41.4E 12 1.0E 12 1,2,3 trimethylbenzene 526 73 8 5.2 5.22 0.00 1.9E+3 000.0E+0 45.6E 9 000.0E+0 1.1E 9 1,2,4 trimethylbenzene 95 63 6 1,511.4 1,511.40 0.00 68.6E+3 000.0E+0 1.7E 6 000.0E+0 41.4E 9 2,2 dibromo 3 nitrilopropionamide 10222 01 2 982.7 653.38 329.33 3.3E+6 1.7E+6 80.0E 6 40.3E 6 3.0E 6 2,3 Dihydroxypropyl trimethylammonium chloride 34004 36 0 19.1 0.00 19.09 12.4E 9 123.2E 3 298.5E 21 3.0E 12 74.4E 15 2 amine 2 methyl propanol 124 68 5 8.7 8.71 0.00 10.1E+0 000.0E+0 243.3E 12 000.0E+0 6.1E 12 2 bromo 3 nitrilopropionamide 1113 55 9 1.5 0.90 0.57 553.4E 3 351.3E 3 13.4E 12 8.5E 12 546.4E 15 2 ethylhexanol 104 76 7 11.9 11.88 0.00 321.4E+0 000.0E+0 7.8E 9 000.0E+0 194.1E 12 3,4,4 trime thyloxazolidine 75673 43 7 43.9 43.94 0.00 12.9E+3 000.0E+0 311.0E 9 000.0E+0 7.8E 9 3 chloro 2 hydroxypropyl trimethylazanium;chloride 3327 22 8 3.8 0.00 3.82 2.0E 3 437.9E+0 47.4E 15 10.6E 9 264.5E 12 3rd Party Additive 462.5 4,4 dimet hyloxazolidine 51200 87 4 881.5 881.45 0.00 3.7E+3 000.0E+0 89.8E 9 000.0E+0 2.2E 9 4 nonylphenyl 127087 87 0 4.1 0.00 4.14 1.0E 3 159.0E+3 24.2E 15 3.8E 6 96.0E 9 Acetic acid 64 19 7 15,784.9 15,784.94 0.00 13.1E+3 000.0E+0 315.4E 9 000.0E+0 7.9E 9 Ace tic anhydride 108 24 7 5.1 5.12 0.00 33.4E+0 000.0E+0 806.8E 12 000.0E+0 20.2E 12 Aldehyde 115.9 115.92 0.00 32.1E+3 000.0E+0 776.6E 9 000.0E+0 19.4E 9 Alkyl dimethyl benzyl ammonium chloride 68424 85 1 197.6 0.00 197.56 313.1E 6 17.4E+3 7.6E 15 419.8E 9 10.5E 9 Alkyl pyridine benzyl quaternary ammonium chloride 68909 18 2 35.5 0.00 35.48 2.5E 6 2.0E+0 60.6E 18 49.1E 12 1.2E 12 Alkylene oxide block polymer 471.7 Aluminum oxide 1344 28 1 574.4 0.00 574.43 Amine salts 21.7 Amines, coco alkyl, ethoxylated 61791 14 8 1.7 0.00 1.74 452.0E 6 2.2E+3 10.9E 15 53.4E 9 1.3E 9

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43 Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ Amines, tallow alkyl, ethoxylated 61791 26 2 9,920.5 0.00 9,920.48 34.4E 9 1.0E+6 832.0E 21 24.5E 6 613.0E 9 Ammonium acetate 631 61 8 17,741. 1 0.00 17,741.14 18.6E 3 944.3E+3 449.2E 15 22.8E 6 570.3E 9 Ammonium chloride 12125 02 9 11,699.0 0.00 11,699.02 48.0E 3 35.5E+6 1.2E 12 857.7E 6 21.4E 6 Ammonium dihydrogen phosphate 7722 76 1 2.8 0.00 2.83 Ammonium hydroxide 1336 21 6 1.3 0 .00 1.29 Ammonium persulfate 7727 54 0 2,682.2 0.00 2,682.17 222.4E 18 1.3E+6 5.4E 27 31.2E 6 779.1E 9 Ammonium phosphite 13446 12 3 1.3 0.00 1.32 21.2E 18 141.6E+0 511.3E 30 3.4E 9 85.5E 12 Ammonium salt 6,732.3 Amphoteric su rfactant 372.5 Antifoam 0.8 Apatite 64476 38 6 43.6 0.00 43.60 16.6E 15 701.9E+3 401.2E 27 17.0E 6 423.9E 9 Bentonite, benzyl(hydrogenated tallow alkyl) dimethylammonium stearate complex 121888 68 4 451.6 B iotite 1302 27 8 43.6 0.00 43.60 16.2E 15 701.9E+3 390.4E 27 17.0E 6 423.9E 9 Borate 7550 67 7 45.8 0.00 45.78 1.9E 15 737.1E+3 46.3E 27 17.8E 6 445.2E 9 Calcite 471 34 1 895.3 0.00 895.27 118.8E 9 14.4E+6 2.9E 18 348.2E 6 8.7E 6 Calcium chloride 10043 52 4 958.3 0.00 958.30 3.6E 15 15.4E+6 87.5E 27 372.7E 6 9.3E 6 Carboxymethyl guar gum, sodium salt 39346 76 4 16,503.7 Chlorous acid, sodium salt 7758 19 2 8,802.1 0.00 8,802.06 18.4E 21 884.5E+0 444.8E 33 21.4E 9 534.2E 12 Choline chlori de 67 48 1 6,265.0 0.00 6,264.99 2.4E 6 8.1E+3 57.8E 18 194.8E 9 4.9E 9 Cinnamaldehyde 104 55 2 0.0 0.00 0.00 1.0E+0 000.0E+0 24.3E 12 000.0E+0 608.6E 15 Citric acid 77 92 9 2.6 0.00 2.58 3.5E 6 4.1E+0 84.5E 18 99.2E 12 2.5E 12 Clay 334.8 0.00 334.76 49.2E 15 5.4E+6 1.2E 24 130.2E 6 3.3E 6 Cobalt acetate 71 48 7 192.2 0.09 192.12 1.4E+3 3.1E+6 33.3E 9 74.7E 6 1.9E 6 Dibromoacetonitrile 3252 43 5 108.7 108.73 0.00 1.2E+3 000.0E+0 29.3E 9 000.0E+0 733.6E 12

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44 Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ Didecyl dimethyl ammonium chloride 111 42 2 355.2 0.42 354.74 1.7E+0 1.4E+3 40.6E 12 34.3E 9 857.3E 12 Diethylenetriamine 111 40 0 38.7 38.66 0.00 119.5E+0 000.0E+0 2.9E 9 000.0E+0 72.2E 12 Dinonyphenyl 9014 93 1 4.1 0.27 3.88 4.3E+3 62.4E+3 103.4E 9 1.5E 6 40.3E 9 EDTA/copper chelate 14025 15 1 1,503.8 0.00 1,503.80 2.3E 15 4.1E+3 54.5E 27 98.4E 9 2.5E 9 EO C7 9 iso, C8 rich alcohols 78330 19 5 4.6 0.00 4.63 44.2E 3 1.6E+3 1.1E 12 37.5E 9 937.8E 12 EO C9 11 iso, C10 rich alcohols 78330 20 8 4.6 4.63 0.00 61.6E+0 000.0E+0 1.5E 9 000.0E+0 37.2E 1 2 Ethanol 64 17 5 48,995.2 48,995.20 0.00 19.8E+3 000.0E+0 478.0E 9 000.0E+0 12.0E 9 Ethoxylated branched C13 alcohol 78330 21 9 2,266.1 160.75 2,105.38 16.4E+3 215.0E+3 396.6E 9 5.2E 6 139.8E 9 Ethylene glycol 107 21 1 2,260.7 150.91 2,109.79 27.5E+0 3 85.1E+0 665.4E 12 9.3E 9 249.2E 12 Fatty acids 0.7 0.71 0.00 11.5E+3 000.0E+0 277.0E 9 000.0E+0 6.9E 9 Fatty acids, tall oil 61790 12 3 591.9 0.39 591.53 4.6E+3 7.0E+6 111.3E 9 168.3E 6 4.2E 6 Formaldehyde amine resin 56652 26 7 1.8 1.85 0.00 22.8E+0 000.0E+0 551.2E 12 000.0E+0 13.8E 12 Formic acid 64 18 6 778.0 777.98 0.00 596.1E+0 000.0E+0 14.4E 9 000.0E+0 360.0E 12 Glutaraldehyde 111 30 8 1,106.3 1,106.30 0.00 220.1E+3 000.0E+0 5.3E 6 000.0E+0 132.9E 9 Glycerine 56 81 5 199.7 0.42 199.31 11.2E 3 5.4E+0 271.5E 15 129.5E 12 3.2E 12 Goethite 1310 14 1 128.7 0.00 128.75 2.9E 15 2.1E+6 70.0E 27 50.1E 6 1.3E 6 Guar gum 9000 30 0 100,655.4 0.00 100,655.40 1.1E 3 370.3E+6 26.5E 15 8.9E 3 223.6E 6 Haloalkyl heteropolycycle salt 0.2 Heav y aliphatic petroleum naphtha solvent 64742 96 7 15.6 15.63 0.00 18.6E+0 000.0E+0 449.4E 12 000.0E+0 11.2E 12 Heavy aromatic petroleum naphtha 64742 94 5 3,540.3 294.32 3,245.98 8.1E+3 89.6E+3 196.2E 9 2.2E 6 59.0E 9 Heavy hydrotreated petroleum naphtha 64742 48 9 27,128.7 15,417.98 11,710.70 1.7E+6 1.3E+6 40.8E 6 31.0E 6 1.8E 6 Hexamethylenetetramine 100 97 0 1,631.3 15.15 1,616.13 2.5E+0 270.6E+0 61.3E 12 6.5E 9 164.9E 12 Hydrated magnesium silicate (talc) 14807 96 6 12.6 0.00 12.62 12.4E 15 203.2E+3 298.9E 27 4.9E 6 122.7E 9 Hydrochloric acid 7641 01 0 39,627.4 0.00 39,627.45 2.1E 15 1.1E+9 50.5E 27 27.1E 3 677.8E 6 Hydrotreated light petroleum distillate 64742 47 8 285,745.4 621.19 285,124.17 204.1E+3 93.7E+6 4.9E 6 2.3E 3 56.7E 6

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45 Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ Hydrotreated med ium petroleum distillates 64742 46 7 6,296.1 87.79 6,208.29 81.1E+6 5.7E+9 2.0E 3 138.5E 3 3.5E 3 Inorganic base 36.5 0.00 36.51 6.2E 15 587.9E+3 149.7E 27 14.2E 6 355.0E 9 Isopropanol 67 63 0 4,937.6 4,937.63 0.00 224.9E+0 000.0E+0 5.4E 9 000.0E+0 135 .8E 12 Isotridecanol, ethoxylated (TDA 6) 9043 30 5 770.6 0.00 770.57 174.0E 6 33.2E+3 4.2E 15 803.1E 9 20.1E 9 Lactic acid 50 21 5 2,447.4 198.07 2,249.29 463.4E 3 5.3E+0 11.2E 12 127.1E 12 3.5E 12 Laury alcohol ethoxylate 68551 12 2 14,482.7 143.63 14 ,339.07 104.0E+3 10.4E+6 2.5E 6 250.7E 6 6.3E 6 Light aromatic petroleum naphtha solvent 64742 95 6 2.8 2.77 0.00 98.3E+0 000.0E+0 2.4E 9 000.0E+0 59.4E 12 Magnesium oxide 1309 48 4 18.1 0.00 18.15 1.3E 15 292.2E+3 31.8E 27 7.1E 6 176.5E 9 Magnesium per oxide 14452 57 4 9.1 0.00 9.06 1.8E 15 145.9E+3 44.4E 27 3.5E 6 88.1E 9 Methanol 67 56 1 2,672.3 2,672.25 0.00 872.8E+0 000.0E+0 21.1E 9 000.0E+0 527.2E 12 Methyl isobutyl ketone 108 10 1 172.6 172.63 0.00 77.3E+0 000.0E+0 1.9E 9 000.0E+0 46.7E 12 Napht halene 91 20 3 536.3 294.30 242.02 4.9E+3 4.0E+3 118.8E 9 97.7E 9 5.4E 9 Naphthenic acid ethoxylate 68410 62 8 94.9 0.00 94.87 142.0E 6 6.0E+3 3.4E 15 145.5E 9 3.6E 9 N dimethyl formamide 68 12 2 0.0 0.00 0.00 925.2E 6 000.0E+0 22.4E 15 000.0E+0 558.8E 1 8 No hazardous ingredients 4.0 No MSDS ingredients (Friction Reducer) 96.1 Nonhazardous 156.2 Non ionic surfactant 22.3 N propanol zirconate 30.5 N propyl zirconate 23519 77 9 3,617.9 0.00 3,617.89 425.5E 18 58.2E+6 10.3E 27 1.4E 3 35.2E 6 Olefin 64743 02 8 0.1 0.05 0.00 14.5E+0 000.0E+0 351.1E 12 000.0E+0 8.8E 12 Organic sulfonic acid 27176 87 0 6.5 0.00 6.52 3.0E 9 956.5E+0 71.5E 21 23.1E 9 577.7E 12 Organic sulfur co mpound 0.0 Oxirane, 2 methyl polymer with oxirane, monodecyl ether 37251 67 5 157.7 0.01 157.73 5.0E+0 59.6E+3 121.3E 12 1.4E 6 36.0E 9 Phenol/formaldehyde resin 9003 35 4 16,252.3 86.60 16,165.72 1.1E+3 199.7E+3 25.8E 9 4.8E 6 121.2E 9

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46 Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ Poly(oxy 1,2 ethanediyl),.alpha. tetradecyl .omega. hydroxy 27306 79 2 786.6 0.02 786.57 54.2E+0 2.7E+6 1.3E 9 66.4E 6 1.7E 6 Poly(tetrafluoroethylene) 9002 84 0 9.4 9.38 0.00 3.1E+0 000.0E+0 75.6E 12 000.0E+0 1.9E 12 Polyethylene glycol 25322 68 3 396 .4 0.01 396.43 1.1E+0 83.4E+3 27.2E 12 2.0E 6 50.4E 9 Polyoxyalkylenes 68951 67 7 318.0 30.52 287.46 47.4E+3 446.4E+3 1.1E 6 10.8E 6 298.2E 9 Polyquaternary amine 48.8 Polysaccharide 68130 15 4 31,931.4 0.00 31,931.35 817.3E 27 638.4E 3 19.7E 36 15.4E 12 385.6E 15 Potassium carbonate 584 08 7 7,394.9 0.00 7,394.87 788.1E 18 84.8E+0 19.0E 27 2.0E 9 51.2E 12 Potassium hydroxide 1310 58 3 3,365.3 0.00 3,365.26 866.5E 24 25.7E+0 20.9E 33 619.7E 12 15.5E 12 Potassium persulfate 7727 21 1 0. 3 0.00 0.31 795.5E 21 452.9E 3 19.2E 30 10.9E 12 273.5E 15 Propanol 71 23 8 6,509.9 6,509.93 0.00 2.0E+3 000.0E+0 47.2E 9 000.0E+0 1.2E 9 Propargyl alcohol 107 19 7 32.0 31.97 0.00 16.4E+3 000.0E+0 395.8E 9 000.0E+0 9.9E 9 Proprietary sesquiolate 8007 4 3 0 7.8 0.00 7.81 2.8E 18 222.2E 3 67.4E 30 5.4E 12 134.2E 15 Propylene glycol 57 55 6 14.4 14.35 0.00 1.6E+0 000.0E+0 38.0E 12 000.0E+0 950.2E 15 Quaternary amine 7,984.7 Quaternary ammonium compound 122 18 9 0.0 0.00 0.04 341.3E 6 14.7 E+0 8.2E 15 356.1E 12 8.9E 12 Quaternary ammonium compounds, bis(hydrogenated tallow alkyl)dimethyl, salts with montmorillonite 68911 87 5 7.8 Quaternary ammonium compounds, bis(hydrotreated tallow alkyl)dimethyl, salts with bentonite 68953 58 2 909.1 Quaternary ammonium salt 27.3 0.00 27.27 341.3E 6 9.4E+3 8.2E 15 226.4E 9 5.7E 9 Silica, amorphous fumed 7631 86 9 105.2 0.00 105.18 19.4E 18 16.8E+3 468.3E 30 404.7E 9 10.1E 9 Sodium bicarbonate 144 55 8 526.1 0.00 526.05 10.4E 6 14.0E+0 250.9E 18 339.0E 12 8.5E 12 Sodium bromide 7647 15 6 108.7 0.00 108.73 30.3E 18 15.8E+3 731.5E 30 381.5E 9 9.5E 9 Sodium chloride 7647 14 5 42,603.8 0.00 42,603.77 473.7E 18 170.4E+6 11.4E 27 4.1E 3 102.9E 6

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47 Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ Sodium erythorbate 6381 77 7 0.8 0.00 0.78 12.4E 15 776.0E 3 299.5E 27 18.7E 12 468.6E 15 Sodium hydroxide 1310 73 2 174.8 0.00 174.81 61.1E 15 5.4E+6 1.5E 24 131.1E 6 3.3E 6 Sodium hypochlorite 7681 52 9 4,825.1 0.00 4,825.09 1.6E 18 49.6E+3 37.5E 30 1.2E 6 30.0E 9 Sodium iodide 7 681 82 5 2.8 0.00 2.83 49.5E 18 461.6E+0 1.2E 27 11.2E 9 278.8E 12 Sodium lactate 72 17 3 758.9 0.00 758.91 2.7E 6 44.7E+0 65.5E 18 1.1E 9 27.0E 12 Sodium perborate tetrahydrate 10486 00 7 92.1 0.00 92.13 5.0E 15 1.5E+6 121.2E 27 35.8E 6 895.8E 9 Sodium persulfate 7775 27 1 144.2 0.00 144.17 1.5E 18 447.7E+0 36.2E 30 10.8E 9 270.4E 12 Sodium sulfate 7757 82 6 0.2 0.19 0.00 699.3E 3 000.0E+0 16.9E 12 000.0E+0 422.3E 15 Sorbitan monooleate polyoxyethylene derivative 9005 65 6 175.3 0.00 175.29 9.0E 27 3. 2E+6 217.0E 39 77.4E 6 1.9E 6 Sorbitan, mono 9 octadecenoate, (Z) 1338 43 8 172.6 0.00 172.57 346.7E 9 502.0E+3 8.4E 18 12.1E 6 303.2E 9 Soybean oil methyl ester 67784 80 9 1,434.7 0.03 1,434.64 982.1E+0 48.3E+6 23.7E 9 1.2E 3 29.1E 6 Styrene acrylic co polymer 25085 34 1 545.8 0.76 545.02 4.4E+0 3.2E+3 106.0E 12 76.3E 9 1.9E 9 Sucrose 57 50 1 0.2 0.00 0.21 43.0E 15 2.8E 3 1.0E 24 66.5E 15 1.7E 15 Surfactants 1,131.8 1,131.79 0.00 51.5E+0 000.0E+0 1.2E 9 000.0E+0 31.1E 12 Tall oil acid diethanolamide 68155 20 4 106.8 0.00 106.81 14.6E 6 265.7E+3 352.7E 18 6.4E 6 160.4E 9 Terpenes and terpenoids 68956 56 9 1,346.0 1,345.97 0.00 380.9E+0 000.0E+0 9.2E 9 000.0E+0 230.1E 12 Terpenes and terpenoids, sweet orange oil 68647 72 3 32,901.6 5,299.60 27,601.97 1.1E+6 5.7E+6 26.3E 6 137.2E 6 4.1E 6 Tert butyl hydroperoxide 75 91 2 380.0 379.99 0.00 13.7E+3 000.0E+0 329.8E 9 000.0E+0 8.2E 9 Tetramethyl ammonium chloride 75 57 0 162.9 0.00 162.95 186.9E 6 857.2E+0 4.5E 15 20.7E 9 517.7E 12 Thiourea polymer 6852 7 49 1 0.7 0.25 0.47 142.7E 3 269.9E 3 3.4E 12 6.5E 12 249.2E 15 Trade secret 1,909.1 Triethanolamine 102 71 6 7,491.0 0.01 7,490.99 4.1E 3 2.1E+3 98.9E 15 51.2E 9 1.3E 9 Triethanolamine zirconate 101033 44 7 665.7 0.00 665.71 Triethylene glycol 112 27 6 529.2 5.36 523.80 328.9E 3 32.2E+0 7.9E 12 777.2E 12 19.6E 12 Triisopropanolamine 122 20 3 1.8 0.05 1.74 74.2E 3 2.6E+0 1.8E 12 61.9E 12 1.6E 12 Trimethylamine 75 50 3 34.7 34.71 0.00 14.2E+0 000.0E+0 343.9E 12 000.0E+0 8.6E 12

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48 Chemical CAS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Average Impact per Well per Unit Energy (PDF.m3.day)/MJ Various oxides and trace elements (Fe2O3, CaO, and MgO) are the largest fractions 13,248.3 0.00 13,248.29 5.2E 15 213.3E+6 125.8E 27 5.2E 3 128.8E 6 Vinylidene chloride methyl acrylate copolymer 25038 72 6 72.2 72.17 0.00 10.5E+3 000.0E+0 254.4E 9 0 00.0E+0 6.4E 9 Xylene 1330 20 7 2.6 2.61 0.00 42.3E+0 000.0E+0 1.0E 9 000.0E+0 25.5E 12 Zirconium complex 1,162.3 Zirconium sodium hydroxy lactate complex 113184 20 6 86.3 0.00 86.29 000.0E+0 1.4E+6 000.0E+0 33.6E 6 839.1E 9 Zirconium s olution 372.4 Zirconium, acetate lactate oxo ammonium complexes 68909 34 2 14,017.1 0.00 14,017.07 246.8E 9 222.0E+0 6.0E 18 5.4E 9 134.1E 12 Table 12 Environme ntal impact for Weld County by c hemical Chemical C AS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Ave rage Impact per Well per Unit Energy (PDF.m3.day)/MJ 2 butoxyethanol 111 76 2 442.0 20.82 421.21 17.3E+0 350.5E+0 11.6E 9 234.6E 9 24.6E 9 Acetic acid 64 19 7 16.6 16.64 0.00 13.8E+0 000.0E+0 9.2E 9 000.0E+0 921.6E 12 Alkyl amine surfactant 0.1 Amines, tallow alkyl, ethoxylated 61791 26 2 0.1 0.00 0.05 33.3E 9 5.5E+0 22.3E 18 3.7E 9 368.3E 12 Amphoteric surfactant 335.9 Cinnamaldehyde 104 55 2 0.5 0.51 0.00 272.9E+0 000.0E+0 182.7E 9 000.0E+0 18.3E 9 Crystalline silica quartz 14808 60 7 746,410.3 0.00 746,410.33 1.9E 15 12.0E+9 1.3E 24 8.0E+0 804.4E 3

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49 Chemical C AS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Ave rage Impact per Well per Unit Energy (PDF.m3.day)/MJ Disodium ethylene diaminediacetate 38011 25 5 0.0 0.00 0.03 24.2E 12 251.9E 9 16.2E 21 168.6E 18 16.9E 18 Enzyme 0.1 Ethoxylated decyl alcohol 0.2 0. 23 0.00 5.1E+0 000.0E+0 3.4E 9 000.0E+0 339.2E 12 Ethylene glycol 107 21 1 306.3 145.78 160.56 26.6E+0 29.3E+0 17.8E 9 19.6E 9 3.7E 9 Fatty acids, tall oil 61790 12 3 0.4 0.38 0.00 4.5E+3 15.2E+0 3.0E 6 10.2E 9 299.0E 9 Glycerine 56 81 5 6.7 0.40 6.33 1 0.9E 3 170.3E 3 7.3E 12 114.0E 12 12.1E 12 Guar gum 9000 30 0 2,719.3 0.00 2,719.31 1.1E 3 10.0E+6 708.3E 15 6.7E 3 669.6E 6 Hydrochloric acid 7641 01 0 1,782.6 0.00 1,782.56 2.0E 15 50.5E+6 1.4E 24 33.8E 3 3.4E 3 Isopropanol 67 63 0 1.4 1.36 0.00 61.8E 3 000.0E+0 41.3E 12 000.0E+0 4.1E 12 Laury alcohol ethoxylate 68551 12 2 0.7 0.71 0.00 510.3E+0 000.0E+0 341.6E 9 000.0E+0 34.2E 9 Methanol 67 56 1 442.0 442.02 0.00 144.4E+0 000.0E+0 96.6E 9 000.0E+0 9.7E 9 Nitrilotriacetate, trisodium salt (NTA) 5064 31 3 0.1 0.00 0.09 66.0E 9 1.0E 3 44.2E 18 696.3E 15 69.6E 15 Nitrogen 7727 37 9 433,766.0 0.00 433,765.96 2.7E 18 21.0E+6 1.8E 27 14.0E 3 1.4E 3 Organic polyol 6.7 Poly(oxy 1,2 ethanediyl),.alpha. tetradecyl .omega. hydroxy 27306 79 2 0.0 0.01 0.01 52.3E+0 24.9E+0 35.0E 9 16.7E 9 5.2E 9 Polyether 0.0 Sodium chloride 7647 14 5 7.2 0.00 7.24 457.6E 18 28.9E+3 306.3E 27 19.4E 6 1.9E 6 Sodium erythorbate 6381 77 7 2.0 0.00 1.99 12.0E 15 2.0E+0 8.0E 24 1.3E 9 132.3E 12 So dium hydroxide 1310 73 2 0.1 0.00 0.05 59.0E 15 1.7E+3 39.5E 24 1.1E 6 111.8E 9 Sodium hydroxyacetate 2836 32 0 0.1 0.12 0.00 846.5E 6 000.0E+0 566.6E 15 000.0E+0 56.7E 15 Sucrose 57 50 1 15.4 0.00 15.38 41.5E 15 202.4E 3 27.8E 24 135.5E 12 13.5E 12 Tet rasodium ethylenediamine tetraacetate 64 02 8 1.7 0.00 1.67 31.8E 3 27.0E+3 21.3E 12 18.0E 6 1.8E 6

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50 Chemical C AS Number Mass Removed f rom Well (kg) Evaporative Mass (kg) Mass in Water (kg) Emissions to Rural Air (PDF.m3.day) Emissions to Fresh Water (PDF.m3.day) Total Air Impact per Unit Energy (PDF.m3.day)/MJ Total Water Impact per Unit Energy (PDF.m3.day)/MJ Ave rage Impact per Well per Unit Energy (PDF.m3.day)/MJ Trisodium ethylenediaminetriacetate 19019 43 3 0.1 0.00 0.05 7.1E 9 1.8E 3 4.8E 18 1.2E 12 122.1E 15

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51 Table 12 and Table 11 depict the environmental impact for Weld and Las Animas counties, respectively. The column descriptions are as follows: Mass Removed from Well (kg) | the total mass that returns to the surface as flo wback: Evaporative Mass (kg) | the total mass that evaporates from the pit into the air: Mass in Water (kg) | the total mass that remains in the pit after evaporation: Emissions to Rural Air (PDF.m3.day) | the product of the evaporative mass and the rural air categorization factor: Emissions to Fresh Water (PDF.m3.day) | the product of the mass in water and the fresh water categorization factor: Total Air Impact per Unit Energy (PDF.m3.day)/MJ | applies the functional unit to the emissions to rural air generating the air impact per unit energy: Total Water Impact per Unit Energy (PDF.m3.day)/MJ | applies the functional unit to the emissions to freshwater generating the freshwater impact per unit energy: Average Impact per Well per Unit Energy (PDF.m3.day)/MJ | sums the rural air and freshwater impacts per unit energy over the total wells in the analysis generating the impact of all chemica ls used per well in that coun ty: (17) The summation of all chemicals from Equation 17 will produce the environmental impact for all chemicals per average well in each county, shown i n Table 13

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52 Table 13 Summary of impact for each county Weld County, Regular Oil and Gas Wells Las Animas County, Coal Bed Methane Wells Average Ratio (LA/W ) Average per Chemical Average per Wel l Average per Chemical Average per Well Mass Removed f rom Well (kg) 5.7E+3 21.5E+3 15.2E+3 44.0E+3 204.24% Evaporative Mass (kg) 854.3E+0 2.8E+3 26.2E+0 62.9E+0 2.28% Mass in Water (kg) 5.5E+3 17.8E+3 18.3E+3 43.9E+3 246.04% Emission to Rural Air (PDF .m3.day) 703.9E+3 2.2E+6 229.0E+0 549.5E+0 0.02% Emissions to Freshwater (PDF.m3.day) 63.5E+6 198.4E+6 3.4E+6 8.2E+6 4.11% Total Air Impact per Unit Energy (PDF.m3.day/MJ) 17.0E 6 53.1E 6 153.3E 9 367.8E 9 0.69% Total Water Impact per Unit Energy (PDF.m 3.day/MJ) 1.5E 3 4.8E 3 2.3E 3 5.5E 3 113.87% Average Impact per Unit Energy (PDF.m3.day/MJ) 4.8E 3 5.5E 3 112.63% Delivering energy from coal bed methane wells in Las Animas county produces 12.6% more impact from chemicals to the environment as trad itional oil and gas wells in Weld County per unit energy delivered for the average hydraulic fracturing well CBM wells had negligible absolute emissions to air and low absolute emissions to water compared to oil and gas wells, but the impact increases gr eatly when the relative impact of energy (the functional unit) output is included. In both cases the impact in air was three to six orders of magnitude smaller than the impact in water. There were several possible reasons for t his difference : The average well in Las Animas County produced 44.4% more energy over its lifetime than the average well Weld County which aids in reducing the impact of CBM wells The fraction of chemicals that return in the flowback are very different for oil and gas wells (17.5% ) compared to coal bed methane (61.0%) wells in our assessment. This variable multiplied by the mass of a chemicals originating the injection fluid governs the mass of chemicals that enter the disposal pit, which was the mass used to ascertain the impact. The value of the flowback fraction is proportional to the impact chemicals will have on the well. The flowback fractions that were used came from sparse data, relying on many variables, yielding a large range of possible values; flowback

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53 fractions can r ange from 1 to 83%, and even for the Niobrara formation values between 8 and 27% are of ten as precise as can be reliable used 3 The same flowback fraction for both sets of wells would have the impact be greatly lessened for the CBM wells. A f lowback of 19.7% for wells in Weld County would generated the same environmental impact per well as for wells in L as Animas if flowback remains the same Conversely, a flowback of 54.2% for Las Animas wells would generate the same impact compared to Weld County. As the flowback fraction increases our calculations say that the environmental impact would increase propo rtional ly but a large factor not included in our assessment is the impact of chemicals that remain underground. Due to the low flowback fraction for Weld County these chemicals might have a significant impact, but t here is little information regarding th ese chemicals, so it was decided to leave them outside the scope of this analysis. Wells in Weld County must be drilled to a deeper depth than in Las Animas, and as a result subterranean chemicals have a larger distance to migrate before they reach the sur face or an aquifer. It is not known how much these chemicals will impact the environment or if they are safely stratified within their wells.

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54 7 Conclusions and Future Work Qualitatively the assessment seems to yield more accurate and p recise results for Las Animas, due to only one company being used. T he vast majority of wells drilled are from Pioneer Natural Resources being the reason we only used wells operated by them ; Weld County has dozens of operators. The geology in which wells were drilled in Las Animas is slightly more homogenous compared to Weld County, and as a result the fracking fluids used were all very similar. Because one company was used as an operator, the fracking fluid would be more similar for the coal bed methane wells. In short the variations between the Las Animas wells were smaller than Weld County. Las Animas only 212 registered wells on FracFocus.org, but Weld County has 7,131 2 The well selection process was entirely randomized, which meant the chances of getting two wells with very different fluid compositions was much higher in Weld County, especially because there were many different companies operating wells compared to Las Animas County. Ideally a ra ndom subsection would statistically yield the average results, it is very possible that the selection of wells caused the results to be skewed. This was very less likely in Las Animas County. Future research would aim to have a strong methodology for wel l selection, or, ideally, automate the well selection process to extract information out for every single well in each county. Most data acquired for the analysis was input manually, a very tedious process that greatly reduced the quantity of wells we cou ld analyze. Our overall methodology employed through the analysis will work regardless of the method the data was acquired; the various sheets and databases generated through this research was developed to optimize future automation. Once all the data is acquired and cleaned, the further steps to analyze the wells, chemicals, output, and impact become relatively easy

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55 Although there were not many inorganic compounds relative to the total chemical inventory, there were enough to cause problems as inorganics are not able to be predicted in EPISuite and ECOSAR Finding a better way to include inorganic compounds would further increase the accuracy of any similar assessments. The goal of this work was to identify a standard way of assessing chemicals that coul d be applied throughout t he industry and apply them to any selection of wells and their chemicals. Although various methodologies exist to accomplish this goal, our literature review showed that they are fragment ed with sources, techniques, and assumptio ns largely devised per paper and not standardized with other research. Furthermore, this data does not exist in an easily extracted form and is disjointed in multiple locations and therefore is uneven between sources. Since USEtox is a widely used model, we conclude that standardizing the data for input into USEtox makes the most sense. Our methodology is built around that assumption and all data is optimized for input into USEtox. A database of all chemicals found in hydraulic fracturing with their pro perties could be created (expanded from ours), which will be beneficial as it would have all the properties easily vetted by an applicable agency, probably the EPA, easily attainable, and most importantly standardized with others performing similar researc h. The best case values for properties that lack experimental data should be included for chemicals without data. As better estimates and experimental data is found it will be added to the database, increasing the accuracy as time progresses. Informatio n need only be extracted, not researched from various s ources and prediction programs.

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56 REFERENCES (1) Broderick, J.; Anderson, K.; Wood, R.; Paul, G.; Sharmina, M.; Footitt, A. Shale gas an updated assessmen t of environmental and climate change impacts ; Manchester, 2011. (2) FracFocus.org fracfocus.org. (3) US Environmental Protection Agency. Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources (External Re view Draft) ; Washington, D.C., 2015. (4) Aminto, A.; Olson, M. S. Four compartment partition model of hazardous components in hydraulic fracturing fluid additives. J. Nat. Gas Sci. Eng. 2012 7 16 21. (5) Hamm, K. Colorado oil and gas wells by the numbe rs http://www.denverpost.com/datacenter/ci_27519246/colorado oil and gas wells by numbers (accessed Jan 10, 2016). (6) Ptron, G.; Karion, A.; Sweeney, C.; Miller, B. R.; Montzka, S. A.; Frost, G. J.; Trainer, M.; Tans, P.; Andrews, A.; Kofler, J.; et al. A new look at methane and nonmethane hydrocarbon emissions from oil and natural gas operations in the Colorado Denver Julesburg Basin. J. Geophys. Res. Atmos. 2014 119 (11), 6836 6852. (7) US Environmental Protection Agency. Evaluation of Impacts to Und erground Sources of Drinking Water by Hydraulic Fracturing of Coalbed Methane Reservoirs Final ; 2004. (8) US Energy Information Administration. Coalbed Methane Production, by State http://www.eia.gov/dnav/ng/ng_prod_coalbed_s1_a.htm (accessed Feb 16, 2016 ). (9) US Energy Information Administration. Coalbed Methane Proven Reserves, by State http://www.eia.gov/dnav/ng/ng_enr_coalbed_a_EPG0_R51_Bcf_a.htm (accessed Feb 16, 2016). (10) Warner, N. R.; Christie, C. A.; Jackson, R. B.; Vengosh, A. Impacts of Sha le Gas Wastewater Disposal on Water Quality in Western Pennsylvania. Environ. Sci. Technol. 2013 47 (20), 11849 11857. (11) Lester, Y.; Ferrer, I.; Thurman, E. M.; Sitterley, K. A.; Korak, J.; Aiken, G.; Linden, K. G. Characterization of hydraulic fractu ring flowback water in Colorado: Implications for water treatment. Sci. Total Environ. 2015 512 513 637 644. (12) Immig, J. Toxic Chemicals in the Exploration and Production of Gas from Unconventional Sources. Natl. Toxics Netw. 2013 No. April.

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57 (13) Z iemkiewicz, P.; Quaranta, J. D.; McCawley, M. Practical measures for reducing the risk of environmental contamination in shale energy production. Environ. Sci. Process. Impacts 2014 16 (7), 1692. (14) Hauschild, M. Z.; Huijbregts, M. A. J.; Jolliet, O.; MacLeod, M.; Margni, M.; van de Meent, D.; Rosenbaum, R. K.; McKone, T. E. Building a Model Based on Scientific Consensus for Life Cycle Impact Assessment of Chemicals: The Search for Harmony and Parsimony. Environ. Sci. Technol. 2008 42 (19), 7032 7037. (15) Rosenbaum, R. K.; Bachmann, T. M.; Gold, L. S.; Huijbregts, M. A. J.; Jolliet, O.; Juraske, R.; Koehler, A.; Larsen, H. F.; MacLeod, M.; Margni, M.; et al. USEtox the UNEP SETAC toxicity model: recommended characterisation factors for human toxicity and freshwater ecotoxicity in life cycle impact assessment. Int. J. Life Cycle Assess. 2008 13 (7), 532 546. (16) Rosenbaum, R. K.; Huijbregts, M. A. J.; Henderson, A. D.; Margni, M.; McKone, T. E.; van de Meent, D.; Hauschild, M. Z.; Shaked, S.; Li, D. S.; Gold, L. S.; et al. USEtox human exposure and toxicity factors for comparative assessment of toxic emissions in life cycle analysis: sensitivity to key chemical properties. Int. J. Life Cycle Assess. 2011 16 (8), 710 727. (17) Henderson, A. D.; Hausc hild, M. Z.; van de Meent, D.; Huijbregts, M. A. J.; Larsen, H. F.; Margni, M.; McKone, T. E.; Rosenbaum, R. K.; Jolliet, O. USEtox fate and ecotoxicity factors for comparative assessment of toxic emissions in life cycle analysis: sensitivity to key chemic al properties. Int. J. Life Cycle Assess. 2011 16 (8), 701 709. (18) Vandecasteele, I.; Mar Rivero, I.; Sala, S.; Baranzelli, C.; Barranco, R.; Batelaan, O.; Lavalle, C. Impact of Shale Gas Development on Water Resources A Case Study in Northern Poland. Environ. Manage. 2015 55 (6), 1285 1299. (19) U.S. House of Representatives Committee on Energy and Commerce. Chemicals Used in Hydraulic Fracturing ; 2011. (20) FracFocus.org. Chemical Use http://fracfocus.org/chemical use (accessed Oct 19, 2015). (21) Stringfellow, W. T.; Domen, J. K.; Camarillo, M. K.; Sandelin, W. L.; Borglin, S. Physical, chemical, and biological characteristics of compounds used in hydraulic fracturing. J. Hazard. Mater. 2014 275 37 54. (22) Chemicalize.org http://www.chemicali ze.org/. (23) PubChem.gov https://pubchem.ncbi.nlm.nih.gov/. (24) ToxNet.gov http://toxnet.nlm.nih.gov/. (25) US Environmental Protection Agency. Estimation Programs Interface Suite TM for Microsoft

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58 Windows, v4.11. United States Environmental Protection Agency Washington, DC, USA 2016. (26) Mayo Bean, K.; Moran Bruce, K.; Meyland, W. M.; Ranslow, P. ECOSAR Methodology Document. US Environmental Protection Agency May 2012, p 46. (27) Mayo Bean, K.; Moran Bruce, K.; Nabholz, J. V.; Meyland, W. M.; Howa rd, P. H. ECOSAR Operation Manual. US Environmental Protection Agency 2012, p 60. (28) Huijbregts, M. A. J.; Meent, D. van de; Margni, M.; Jolliet, O.; Resenbaum, R.; McKone, T. E.; Hauschild, M. Z. USEtox 2.0 Manual: Organic Substance (v2). USEtox.org 2015, p 18. (29) Huijbregts, M. A. J.; Margni, M.; Hauschild, M. Z.; Jolliet, O.; McKone, T. E.; Resenbaum, R.; Meent, D. van de. USEtox 2.0 Manual: Inorganic Substance (v2). USEtox.org USEtox August 25, 2015, p 18. (30) Travis, C. C.; Arms, A. D. Bioco ncentration of organics in beef, milk, and vegetation. Environ. Sci. Technol. 1988 22 (3), 271 274. (31) Clark, C. E.; Burnham, A.; Harto, C.; Horner, R. Hydraulic fracturing and shale gas production: Technology, Impacts, and Policy ; 2013. (32) Jiang, M .; Hendrickson, C. T.; Vanbriesen, J. M. Life cycle water consumption and wastewater generation impacts of a Marcellus shale gas well. Environ. Sci. Technol. 2014 48 (3), 1911 1920. (33) Puri, R.; King, G. E.; Palmer, I. D. Damage to Coal Permeability Du ring Hydraulic Fracturing. In Low Permeability Reservoirs Symposium ; Society of Petroleum Engineers: Denver, 1991. (34) Mackay, D.; van Wesenbeeck, I. Correlation of Chemical Evaporation Rate with Vapor Pressure. Environ. Sci. Technol. 2014 48 (17), 1025 9 10263. (35) Colorado Oil and Gas Conservation Commission Website http://cogcc.state.co.us/#/home. (36) Ferrer, I.; Thurman, E. M. Chemical constituents and analytical approaches for hydraulic fracturing waters. Trends Environ. Anal. Chem. 2015 5 18 2 5. (37) Guerra, K. L.; Dahm, K. G.; Dundorf, S. Oil and Gas Produced Water Management and Beneficial Use in the Western United States. Sci. Technol. Progr. 2011 No. 157, 129. (38) Huijbregts, M. A. J.; Margni, M.; Hauschild, M. Z.; Jolliet, O.; McKone, T. E.; Resenbaum, R.; Meent, D. van de. USEtox 2.0 User Manual (v2). USEtox.org 2015, p 30.

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59 Appendix A Annual Oil and Gas Production per Well Table 14 Annual oil production values for wells in Weld County Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 12459 5.76E+ 06 3.44E+ 06 3.18E+ 06 3.70E+ 06 4.53E+ 06 2.67E+ 06 2.39E+ 06 3.18E+ 06 2.58E+ 06 3.08E+ 06 1.84E+ 06 1.21E+0 6 1.53E+ 07 4.20E+ 07 3.00E+ 07 1.01E+ 07 8.60E+ 06 12629 5.85E+ 06 8. 56E+ 06 3.29E+ 06 5.57E+ 06 6.57E+ 06 1.21E+ 07 6.21E+ 06 4.35E+ 06 3.99E+ 06 3.16E+ 06 2.77E+ 06 3.03E+0 6 8.12E+ 06 9.23E+ 06 8.63E+ 06 7.82E+ 06 5.62E+ 06 19794 2.88E+ 06 3.11E+ 07 2.25E+ 07 2.93E+ 07 2.49E+ 07 2.59E+ 07 2.60E+ 07 2.65E+ 07 2.14E+ 07 1.86E+ 07 1.63E+ 07 9.94E+0 6 1.77E+ 05 9.79E+ 05 1.28E+ 06 5.93E+ 05 4.70E+ 05 20613 0.00E+ 00 3.14E+ 07 1.17E+ 07 7.06E+ 06 5.78E+ 06 3.48E+ 06 2.86E+ 06 0.00E+ 00 0.00E+ 00 0.00E+ 00 9.91E+ 05 3.04E+0 7 1.30E+ 07 1.20E+ 07 1.57E+ 07 7.30E+ 06 5.78E+ 06 21028 2.63E+ 06 6.67E+ 06 6.36E+ 06 4.95E+ 06 3.16E+ 0 6 2.70E+ 06 4.67E+ 06 3.14E+ 06 1.74E+ 06 2.33E+ 07 1.12E+ 07 5.52E+0 6 6.07E+ 06 9.73E+ 06 1.27E+ 07 5.90E+ 06 4.67E+ 06 21514 3.61E+ 05 1.28E+ 07 8.54E+ 06 6.57E+ 06 6.04E+ 06 4.81E+ 06 4.17E+ 06 4.48E+ 06 8.59E+ 06 9.29E+ 06 4.80E+ 06 4.07E+0 6 3.84E+ 06 7.34E+ 06 9.57E+ 06 4.45 E+ 06 3.53E+ 06 24914 2.72E+ 07 7.43E+ 07 2.59E+ 07 1.60E+ 07 1.19E+ 07 6.09E+ 06 0.00E+ 00 6.12E+ 03 7.48E+ 03 1.12E+ 04 7.39E+ 03 1.06E+0 4 9.08E+ 03 1.73E+ 04 2.26E+ 04 1.05E+ 04 8.33E+ 03 25988 2.21E+ 07 6.32E+ 07 7.73E+ 06 8.40E+ 06 6.66E+ 06 2.23E+ 06 0.00E+ 00 7.95E+ 04 9.7 3E+ 04 1.46E+ 05 9.61E+ 04 1.37E+0 5 1.18E+ 05 2.25E+ 05 2.94E+ 05 1.37E+ 05 1.08E+ 05 29021 2.25E+ 07 2.43E+ 07 1.29E+ 07 9.67E+ 06 9.10E+ 06 1.09E+ 07 1.01E+ 07 8.44E+ 06 1.03E+ 07 1.55E+ 07 1.02E+ 07 1.46E+0 7 1.25E+ 07 2.39E+ 07 3.12E+ 07 1.45E+ 07 1.15E+ 07 29022 2.77E+ 07 1. 59E+ 07 7.81E+ 06 8.68E+ 06 3.83E+ 06 9.19E+ 06 6.19E+ 06 5.16E+ 06 6.32E+ 06 9.47E+ 06 6.24E+ 06 8.92E+0 6 7.66E+ 06 1.46E+ 07 1.91E+ 07 8.87E+ 06 7.03E+ 06 30906 0.00E+ 00 1.01E+ 07 4.78E+ 06 1.92E+ 06 2.11E+ 06 1.28E+ 06 8.61E+ 05 7.19E+ 05 8.80E+ 05 1.32E+ 06 8.68E+ 05 1.24E+0 6 1.07E+ 06 2.04E+ 06 2.66E+ 06 1.24E+ 06 9.79E+ 05 31642 2.07E+ 07 2.04E+ 08 9.03E+ 07 3.60E+ 07 2.91E+ 07 3.00E+ 07 2.02E+ 07 1.69E+ 07 2.07E+ 07 3.10E+ 07 2.04E+ 07 2.92E+0 7 2.51E+ 07 4.79E+ 07 6.24E+ 07 2.90E+ 07 2.30E+ 07 32368 1.23E+ 08 1.05E+ 08 3.49E+ 07 2.99E+ 07 1.45E+ 0 7 1.34E+ 07 9.00E+ 06 7.52E+ 06 9.19E+ 06 1.38E+ 07 9.08E+ 06 1.30E+0 7 1.12E+ 07 2.13E+ 07 2.78E+ 07 1.29E+ 07 1.02E+ 07 32457 6.65E+ 07 1.40E+ 08 8.19E+ 07 4.57E+ 07 3.09E+ 07 2.85E+ 07 1.92E+ 07 1.60E+ 07 1.96E+ 07 2.94E+ 07 1.94E+ 07 2.77E+0 7 2.38E+ 07 4.55E+ 07 5.93E+ 07 2.76 E+ 07 2.18E+ 07 32795 8.19E+ 06 3.09E+ 07 1.17E+ 07 9.75E+ 06 8.49E+ 06 7.85E+ 06 5.29E+ 06 4.41E+ 06 5.40E+ 06 8.09E+ 06 5.33E+ 06 7.63E+0 6 6.55E+ 06 1.25E+ 07 1.63E+ 07 7.59E+ 06 6.01E+ 06 33361 1.34E+ 08 9.48E+ 07 5.29E+ 07 4.16E+ 07 3.05E+ 07 2.82E+ 07 1.90E+ 07 1.59E+ 07 1.9 4E+ 07 2.91E+ 07 1.92E+ 07 2.74E+0 7 2.35E+ 07 4.50E+ 07 5.86E+ 07 2.73E+ 07 2.16E+ 07 34060 1.04E+ 06 1.12E+ 07 8.40E+ 06 5.67E+ 06 7.62E+ 06 7.05E+ 06 4.75E+ 06 3.97E+ 06 4.85E+ 06 7.27E+ 06 4.79E+ 06 6.85E+0 6 5.88E+ 06 1.12E+ 07 1.46E+ 07 6.81E+ 06 5.40E+ 06 34062 3.14E+ 06 8. 96E+ 07 2.40E+ 07 5.24E+ 06 7.19E+ 06 6.65E+ 06 4.48E+ 06 3.74E+ 06 4.58E+ 06 6.86E+ 06 4.52E+ 06 6.47E+0 6 5.55E+ 06 1.06E+ 07 1.38E+ 07 6.43E+ 06 5.09E+ 06 34066 2.47E+ 06 7.70E+ 06 8.12E+ 06 3.79E+ 06 4.16E+ 06 3.85E+ 06 2.59E+ 06 2.16E+ 06 2.65E+ 06 3.97E+ 06 2.61E+ 06 3.74E+0 6 3.21E+ 06 6.13E+ 06 7.99E+ 06 3.72E+ 06 2.95E+ 06 34068 3.05E+ 06 1.93E+ 07 8.36E+ 06 1.87E+ 06 5.21E+ 06 4.82E+ 06 3.25E+ 06 2.71E+ 06 3.32E+ 06 4.97E+ 06 3.27E+ 06 4.69E+0 6 4.02E+ 06 7.69E+ 06 1.00E+ 07 4.66E+ 06 3.69E+ 06

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60 Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 34509 2.27E+ 06 4.64E+ 07 1.53E+ 07 6.46E+ 06 9.15E+ 0 6 8.47E+ 06 5.70E+ 06 4.76E+ 06 5.82E+ 06 8.73E+ 06 5.75E+ 06 8.23E+0 6 7.06E+ 06 1.35E+ 07 1.76E+ 07 8.18E+ 06 6.48E+ 06 36279 2.04E+ 08 8.64E+ 07 3.11E+ 07 1.02E+ 07 7.45E+ 06 6.89E+ 06 4.64E+ 06 3.87E+ 06 4.74E+ 06 7.10E+ 06 4.68E+ 06 6.70E+0 6 5.75E+ 06 1.10E+ 07 1.43E+ 07 6.66 E+ 06 5.27E+ 06 36468 1.42E+ 08 6.07E+ 07 3.73E+ 07 1.22E+ 07 8.91E+ 06 8.24E+ 06 5.55E+ 06 4.64E+ 06 5.67E+ 06 8.50E+ 06 5.60E+ 06 8.01E+0 6 6.88E+ 06 1.31E+ 07 1.71E+ 07 7.97E+ 06 6.31E+ 06 36853 2.32E+ 08 2.53E+ 08 1.14E+ 08 3.72E+ 07 2.73E+ 07 2.52E+ 07 1.70E+ 07 1.42E+ 07 1.7 4E+ 07 2.60E+ 07 1.71E+ 07 2.45E+0 7 2.10E+ 07 4.02E+ 07 5.24E+ 07 2.44E+ 07 1.93E+ 07 36855 2.54E+ 08 3.69E+ 08 1.64E+ 08 5.34E+ 07 3.91E+ 07 3.62E+ 07 2.44E+ 07 2.03E+ 07 2.49E+ 07 3.73E+ 07 2.46E+ 07 3.52E+0 7 3.02E+ 07 5.77E+ 07 7.52E+ 07 3.50E+ 07 2.77E+ 07 36856 1.92E+ 08 2. 68E+ 08 1.36E+ 08 4.46E+ 07 3.26E+ 07 3.02E+ 07 2.03E+ 07 1.70E+ 07 2.08E+ 07 3.11E+ 07 2.05E+ 07 2.93E+0 7 2.52E+ 07 4.81E+ 07 6.27E+ 07 2.92E+ 07 2.31E+ 07 37401 8.00E+ 07 1.98E+ 08 1.04E+ 08 3.39E+ 07 2.48E+ 07 2.30E+ 07 1.55E+ 07 1.29E+ 07 1.58E+ 07 2.37E+ 07 1.56E+ 07 2.23E+0 7 1.92E+ 07 3.66E+ 07 4.77E+ 07 2.22E+ 07 1.76E+ 07 37728 1.44E+ 08 2.59E+ 08 1.28E+ 08 4.17E+ 07 3.05E+ 07 2.82E+ 07 1.90E+ 07 1.59E+ 07 1.94E+ 07 2.91E+ 07 1.92E+ 07 2.74E+0 7 2.36E+ 07 4.50E+ 07 5.86E+ 07 2.73E+ 07 2.16E+ 07 37790 1.84E+ 08 1.10E+ 08 3.97E+ 07 1.30E+ 07 9.49E+ 0 6 8.77E+ 06 5.91E+ 06 4.93E+ 06 6.04E+ 06 9.05E+ 06 5.96E+ 06 8.53E+0 6 7.32E+ 06 1.40E+ 07 1.82E+ 07 8.48E+ 06 6.72E+ 06 38169 1.88E+ 08 1.34E+ 08 4.83E+ 07 1.58E+ 07 1.15E+ 07 1.07E+ 07 7.19E+ 06 6.01E+ 06 7.35E+ 06 1.10E+ 07 7.25E+ 06 1.04E+0 7 8.91E+ 06 1.70E+ 07 2.22E+ 07 1.03 E+ 07 8.17E+ 06 38415 3.76E+ 08 2.55E+ 08 9.19E+ 07 3.00E+ 07 2.20E+ 07 2.03E+ 07 1.37E+ 07 1.14E+ 07 1.40E+ 07 2.10E+ 07 1.38E+ 07 1.98E+0 7 1.70E+ 07 3.24E+ 07 4.22E+ 07 1.96E+ 07 1.56E+ 07 38416 5.02E+ 08 6.84E+ 08 2.46E+ 08 8.04E+ 07 5.89E+ 07 5.45E+ 07 3.67E+ 07 3.06E+ 07 3.7 5E+ 07 5.62E+ 07 3.70E+ 07 5.30E+0 7 4.55E+ 07 8.68E+ 07 1.13E+ 08 5.27E+ 07 4.17E+ 07 39006 2.26E+ 08 1.21E+ 08 4.37E+ 07 1.43E+ 07 1.05E+ 07 9.67E+ 06 6.52E+ 06 5.44E+ 06 6.65E+ 06 9.98E+ 06 6.57E+ 06 9.40E+0 6 8.07E+ 06 1.54E+ 07 2.01E+ 07 9.35E+ 06 7.41E+ 06 39008 1.75E+ 08 1. 38E+ 08 4.98E+ 07 1.63E+ 07 1.19E+ 07 1.10E+ 07 7.42E+ 06 6.20E+ 06 7.58E+ 06 1.14E+ 07 7.48E+ 06 1.07E+0 7 9.19E+ 06 1.76E+ 07 2.29E+ 07 1.06E+ 07 8.43E+ 06 39009 2.00E+ 08 1.16E+ 08 4.18E+ 07 1.36E+ 07 9.99E+ 06 9.24E+ 06 6.23E+ 06 5.20E+ 06 6.36E+ 06 9.53E+ 06 6.28E+ 06 8.99E+0 6 7.71E+ 06 1.47E+ 07 1.92E+ 07 8.93E+ 06 7.08E+ 06 39010 1.52E+ 08 1.10E+ 08 3.98E+ 07 1.30E+ 07 9.52E+ 06 8.81E+ 06 5.93E+ 06 4.95E+ 06 6.06E+ 06 9.08E+ 06 5.98E+ 06 8.56E+0 6 7.35E+ 06 1.40E+ 07 1.83E+ 07 8.51E+ 06 6.74E+ 06 39088 1.52E+ 08 1.61E+ 08 5.82E+ 07 1.90E+ 07 1.39E+ 0 7 1.29E+ 07 8.67E+ 06 7.24E+ 06 8.85E+ 06 1.33E+ 07 8.74E+ 06 1.25E+0 7 1.07E+ 07 2.05E+ 07 2.67E+ 07 1.24E+ 07 9.85E+ 06 39603 1.87E+ 08 1.99E+ 08 7.17E+ 07 2.34E+ 07 1.71E+ 07 1.59E+ 07 1.07E+ 07 8.92E+ 06 1.09E+ 07 1.64E+ 07 1.08E+ 07 1.54E+0 7 1.32E+ 07 2.53E+ 07 3.30E+ 07 1.53 E+ 07 1.21E+ 07 40388 1.42E+ 08 1.51E+ 08 5.44E+ 07 1.78E+ 07 1.30E+ 07 1.20E+ 07 8.10E+ 06 6.76E+ 06 8.27E+ 06 1.24E+ 07 8.17E+ 06 1.17E+0 7 1.00E+ 07 1.92E+ 07 2.50E+ 07 1.16E+ 07 9.21E+ 06 40503 1.70E+ 08 1.81E+ 08 6.52E+ 07 2.13E+ 07 1.56E+ 07 1.44E+ 07 9.72E+ 06 8.11E+ 06 9.9 2E+ 06 1.49E+ 07 9.80E+ 06 1.40E+0 7 1.20E+ 07 2.30E+ 07 3.00E+ 07 1.39E+ 07 1.10E+ 07 Average, Emp 1.10E+ 08 1.17E+ 08 4.20E+ 07 1.37E+ 07 1.00E+ 07 9.29E+ 06 6.26E+ 06 5.22E+ 06 6.39E+ 06 9.58E+ 06 6.31E+ 06 9.03E+0 6 7.75E+ 06 1.48E+ 07 1.93E+ 07 8.97E+ 06 7.11E+ 06 Total, Em p 4.38E+ 09 4.19E+ 09 1.13E+ 09 2.88E+ 08 2.01E+ 08 1.11E+ 08 6.26E+ 07 4.18E+ 07 3.83E+ 07 5.75E+ 07 3.78E+ 07 5.42E+0 7 4.65E+ 07 7.40E+ 07 3.86E+ 07 1.79E+ 07 1.42E+ 07 Change, Emp 106.35 % 36.03% 32.66% 73.24% 92.50% 67.36% 83.48% 122.32 % 149.90 % 65.87% 143.10 % 85.8 5 % 191.05 % 130.33 % 46.52% 79.21%

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61 Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 Average, Model 1.10E+ 08 1.22E+ 08 5.04E+ 07 2.00E+ 07 1.51E+ 07 1.42E+ 07 9.75E+ 06 8.22E+ 06 9.74E+ 06 1.46E+ 07 9.62E+ 06 1.38E+0 7 1.18E+ 07 2.24E+ 07 2.85E+ 07 1.32E+ 07 1.05E+ 07 Total, Model 4.38E+ 09 4.89E+ 09 2.02E+ 09 7.99E+ 08 6.05 E+ 08 5.66E+ 08 3.90E+ 08 3.29E+ 08 3.90E+ 08 5.84E+ 08 3.85E+ 08 5.50E+0 8 4.72E+ 08 8.95E+ 08 1.14E+ 09 5.30E+ 08 4.20E+ 08 Change, Model 111.52 % 41.24% 39.64% 75.81% 93.54% 68.88% 84.29% 118.47 % 149.90 % 65.87% 143.10 % 85.85 % 189.47 % 127.18 % 46.52% 79.21% Model Re liance 14.17% 43.76% 63.96% 66.84% 80.32% 83.96% 87.29% 90.16% 90.16% 90.16% 90.16% 90.16 % 91.73% 96.61% 96.61% 96.61% Table 15 Annual gas production values for wells in Weld County Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 12459 1.79E+0 7 1.38E+0 7 2.01E+0 7 2.72E+0 7 3.45E+0 7 2.77E+0 7 1.94E+0 7 2.76E+0 7 2.02E+0 7 2.04E+0 7 2.03E+0 7 1.60E+0 7 5.79E+0 7 6.73E+0 7 1.06E+0 8 3.36E+0 7 2.83E+0 7 12629 4.04E+0 6 3.01E+0 7 1.39E+0 7 1.32 E+0 7 1.68E+0 7 1.54E+0 7 1.28E+0 7 1.34E+0 7 1.28E+0 7 1.34E+0 7 1.43E+0 7 9.21E+0 6 1.06E+0 7 1.30E+0 7 1.10E+0 7 6.24E+0 6 4.64E+0 6 19794 6.16E+0 6 3.17E+0 7 2.23E+0 7 1.95E+0 7 2.01E+0 7 2.13E+0 7 2.04E+0 7 1.89E+0 7 1.13E+0 7 1.15E+0 7 1.01E+0 7 5.62E+0 6 5.63E+0 4 9.44E+0 5 2 .80E+0 6 9.48E+0 5 7.84E+0 5 20613 2.06E+0 4 1.47E+0 7 9.19E+0 6 7.00E+0 6 5.63E+0 6 4.44E+0 6 3.22E+0 6 4.33E+0 3 1.30E+0 4 0.00E+0 0 2.64E+0 5 9.91E+0 6 1.01E+0 7 8.00E+0 6 2.37E+0 7 8.03E+0 6 6.64E+0 6 21028 3.28E+0 7 5.65E+0 7 4.55E+0 7 3.40E+0 7 2.56E+0 7 2.10E+0 7 2.72E+0 7 2.08E+0 7 1.76E+0 7 3.99E+0 7 2.65E+0 7 1.45E+0 7 7.80E+0 6 9.82E+0 6 2.91E+0 7 9.86E+0 6 8.15E+0 6 21514 1.24E+0 6 9.56E+0 6 1.20E+0 7 1.41E+0 7 1.35E+0 7 1.42E+0 7 1.51E+0 7 9.56E+0 6 9.43E+0 6 1.11E+0 7 9.94E+0 6 1.57E+0 7 1.49E+0 7 1.75E+0 7 5.18E+0 7 1.76E+0 7 1.45E+0 7 24914 1.19E+0 7 7.04E+0 7 3.88E+0 7 2.95E+0 7 2.51E+0 7 1.36E+0 7 0.00E+0 0 6.06E+0 4 6.36E+0 4 8.59E+0 4 7.25E+0 4 6.31E+0 4 9.03E+0 4 1.06E+0 5 3.14E+0 5 1.06E+0 5 8.80E+0 4 25988 1.08E+0 7 6.02E+0 7 1.38E+0 7 8.88E+0 6 1.12E+0 7 5.12E+0 6 0.00E+0 0 4.95E+0 5 5.19E+0 5 7.01E+0 5 5.92E +0 5 5.15E+0 5 7.37E+0 5 8.65E+0 5 2.56E+0 6 8.68E+0 5 7.18E+0 5 29021 2.06E+0 7 1.57E+0 7 8.73E+0 6 7.23E+0 6 5.86E+0 6 9.10E+0 6 7.30E+0 6 7.48E+0 6 7.84E+0 6 1.06E+0 7 8.94E+0 6 7.79E+0 6 1.11E+0 7 1.31E+0 7 3.87E+0 7 1.31E+0 7 1.08E+0 7 29022 2.03E+0 7 1.28E+0 7 7.51E+0 6 6.20 E+0 6 4.46E+0 6 6.42E+0 6 5.35E+0 6 5.48E+0 6 5.74E+0 6 7.76E+0 6 6.55E+0 6 5.70E+0 6 8.16E+0 6 9.57E+0 6 2.83E+0 7 9.61E+0 6 7.94E+0 6 30906 5.53E+0 5 2.20E+0 6 1.09E+0 6 3.52E+0 5 1.17E+0 5 3.18E+0 5 2.93E+0 5 3.00E+0 5 3.15E+0 5 4.25E+0 5 3.59E+0 5 3.12E+0 5 4.47E+0 5 5.24E+0 5 1 .55E+0 6 5.26E+0 5 4.35E+0 5 31642 2.49E+0 6 4.43E+0 7 2.93E+0 7 1.29E+0 7 8.86E+0 6 5.91E+0 6 5.44E+0 6 5.57E+0 6 5.84E+0 6 7.88E+0 6 6.65E+0 6 5.80E+0 6 8.29E+0 6 9.72E+0 6 2.88E+0 7 9.77E+0 6 8.07E+0 6 32368 4.27E+0 6 5.94E+0 6 3.76E+0 6 3.38E+0 6 4.30E+0 6 3.91E+0 6 3.60E+0 6 3.69E+0 6 3.87E+0 6 5.23E+0 6 4.41E+0 6 3.84E+0 6 5.49E+0 6 6.44E+0 6 1.91E+0 7 6.47E+0 6 5.35E+0 6 32457 2.23E+0 7 5.28E+0 7 4.22E+0 7 3.05E+0 7 1.37E+0 7 1.25E+0 7 1.15E+0 7 1.17E+0 7 1.23E+0 7 1.66E+0 7 1.40E+0 7 1.22E+0 7 1.75E+0 7 2.05E+0 7 6.08E+0 7 2.06E+0 7 1.70E+0 7

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62 Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 32795 5.54E+0 6 4.01E+0 7 1.79E+0 7 1.54E+0 7 1.33E+0 7 1.21E+0 7 1.11E+0 7 1.14E+0 7 1.20E+0 7 1.62E+0 7 1.36E+0 7 1.19E+0 7 1.70E+0 7 1.99E+0 7 5.91E+0 7 2.00E+0 7 1.66E+0 7 33361 3.11E+0 7 6.02E+0 7 2.34E+0 7 1.91E+0 7 1.72E+0 7 1.57E+0 7 1.44E+0 7 1.48E+0 7 1.55E+0 7 2.09E+0 7 1.76E +0 7 1.54E+0 7 2.20E+0 7 2.58E+0 7 7.64E+0 7 2.59E+0 7 2.14E+0 7 34060 6.61E+0 4 6.07E+0 7 3.52E+0 7 1.21E+0 7 1.55E+0 7 1.41E+0 7 1.29E+0 7 1.32E+0 7 1.39E+0 7 1.88E+0 7 1.58E+0 7 1.38E+0 7 1.97E+0 7 2.31E+0 7 6.85E+0 7 2.32E+0 7 1.92E+0 7 34062 7.47E+0 4 5.30E+0 7 2.30E+0 7 1.09 E+0 7 1.08E+0 7 9.86E+0 6 9.07E+0 6 9.29E+0 6 9.74E+0 6 1.32E+0 7 1.11E+0 7 9.67E+0 6 1.38E+0 7 1.62E+0 7 4.81E+0 7 1.63E+0 7 1.35E+0 7 34066 7.58E+0 4 3.52E+0 7 2.82E+0 7 1.13E+0 7 1.20E+0 7 1.09E+0 7 1.00E+0 7 1.03E+0 7 1.08E+0 7 1.46E+0 7 1.23E+0 7 1.07E+0 7 1.53E+0 7 1.80E+0 7 5 .32E+0 7 1.80E+0 7 1.49E+0 7 34068 4.30E+0 5 5.05E+0 7 2.77E+0 7 9.18E+0 6 1.16E+0 7 1.05E+0 7 9.68E+0 6 9.91E+0 6 1.04E+0 7 1.40E+0 7 1.19E+0 7 1.03E+0 7 1.48E+0 7 1.73E+0 7 5.13E+0 7 1.74E+0 7 1.44E+0 7 34509 2.21E+0 5 2.14E+0 7 2.66E+0 7 1.64E+0 7 1.19E+0 7 1.08E+0 7 9.98E+0 6 1.02E+0 7 1.07E+0 7 1.45E+0 7 1.22E+0 7 1.06E+0 7 1.52E+0 7 1.79E+0 7 5.29E+0 7 1.79E+0 7 1.48E+0 7 36279 8.19E+0 7 6.57E+0 7 3.65E+0 7 1.28E+0 7 1.16E+0 7 1.05E+0 7 9.67E+0 6 9.91E+0 6 1.04E+0 7 1.40E+0 7 1.18E+0 7 1.03E+0 7 1.47E+0 7 1.73E+0 7 5.13E+0 7 1.74E+0 7 1.44E+0 7 36468 4.25E+0 7 2.49E+0 7 2.62E+0 7 9.19E+0 6 8.28E+0 6 7.53E+0 6 6.93E+0 6 7.10E+0 6 7.44E+0 6 1.01E+0 7 8.49E+0 6 7.39E+0 6 1.06E+0 7 1.24E+0 7 3.67E+0 7 1.25E+0 7 1.03E+0 7 36853 7.54E+0 7 1.87E+0 8 2.34E+0 8 8.23E+0 7 7.42E+0 7 6.75E+0 7 6.21E+0 7 6.36E+0 7 6.67E+0 7 9.01E+0 7 7.60E +0 7 6.62E+0 7 9.47E+0 7 1.11E+0 8 3.29E+0 8 1.12E+0 8 9.23E+0 7 36855 6.69E+0 7 2.17E+0 8 1.71E+0 8 6.02E+0 7 5.42E+0 7 4.93E+0 7 4.54E+0 7 4.65E+0 7 4.87E+0 7 6.58E+0 7 5.56E+0 7 4.84E+0 7 6.92E+0 7 8.12E+0 7 2.41E+0 8 8.16E+0 7 6.74E+0 7 36856 5.58E+0 7 1.64E+0 8 1.17E+0 8 4.10 E+0 7 3.70E+0 7 3.36E+0 7 3.09E+0 7 3.17E+0 7 3.32E+0 7 4.49E+0 7 3.79E+0 7 3.30E+0 7 4.72E+0 7 5.54E+0 7 1.64E+0 8 5.56E+0 7 4.60E+0 7 37401 1.38E+0 7 7.41E+0 7 3.92E+0 7 1.38E+0 7 1.24E+0 7 1.13E+0 7 1.04E+0 7 1.06E+0 7 1.12E+0 7 1.51E+0 7 1.27E+0 7 1.11E+0 7 1.58E+0 7 1.86E+0 7 5 .51E+0 7 1.87E+0 7 1.54E+0 7 37728 4.03E+0 7 1.07E+0 8 9.11E+0 7 3.20E+0 7 2.88E+0 7 2.62E+0 7 2.41E+0 7 2.47E+0 7 2.59E+0 7 3.50E+0 7 2.96E+0 7 2.57E+0 7 3.68E+0 7 4.32E+0 7 1.28E+0 8 4.34E+0 7 3.59E+0 7 37790 5.19E+0 7 4.86E+0 7 2.70E+0 7 9.48E+0 6 8.54E+0 6 7.77E+0 6 7.15E+0 6 7.32E+0 6 7.68E+0 6 1.04E+0 7 8.75E+0 6 7.63E+0 6 1.09E+0 7 1.28E+0 7 3.79E+0 7 1.28E+0 7 1.06E+0 7 38169 3.87E+0 7 4.66E+0 7 2.59E+0 7 9.08E+0 6 8.19E+0 6 7.45E+0 6 6.85E+0 6 7.02E+0 6 7.36E+0 6 9.94E+0 6 8.39E+0 6 7.31E+0 6 1.04E+0 7 1.23E+0 7 3.63E+0 7 1.23E+0 7 1.02E+0 7 38415 1.29E+0 8 2.07E+0 8 1.15E+0 8 4.03E+0 7 3.63E+0 7 3.30E+0 7 3.04E+0 7 3.11E+0 7 3.27E+0 7 4.41E+0 7 3.72E+0 7 3.24E+0 7 4.64E+0 7 5.44E+0 7 1.61E+0 8 5.46E+0 7 4.52E+0 7 38416 1.31E+0 8 4.80E+0 8 2.67E+0 8 9.36E+0 7 8.44E+0 7 7.68E+0 7 7.06E+0 7 7.24E+0 7 7.59E+0 7 1.02E+0 8 8.65E +0 7 7.53E+0 7 1.08E+0 8 1.26E+0 8 3.74E+0 8 1.27E+0 8 1.05E+0 8 39006 8.58E+0 7 8.33E+0 7 4.63E+0 7 1.62E+0 7 1.46E+0 7 1.33E+0 7 1.23E+0 7 1.26E+0 7 1.32E+0 7 1.78E+0 7 1.50E+0 7 1.31E+0 7 1.87E+0 7 2.19E+0 7 6.50E+0 7 2.20E+0 7 1.82E+0 7 39008 7.13E+0 7 1.11E+0 8 6.16E+0 7 2.16 E+0 7 1.95E+0 7 1.77E+0 7 1.63E+0 7 1.67E+0 7 1.75E+0 7 2.37E+0 7 2.00E+0 7 1.74E+0 7 2.49E+0 7 2.92E+0 7 8.65E+0 7 2.93E+0 7 2.42E+0 7 39009 9.82E+0 7 7.84E+0 7 4.35E+0 7 1.53E+0 7 1.38E+0 7 1.25E+0 7 1.15E+0 7 1.18E+0 7 1.24E+0 7 1.67E+0 7 1.41E+0 7 1.23E+0 7 1.76E+0 7 2.06E+0 7 6 .11E+0 7 2.07E+0 7 1.71E+0 7 39010 7.24E+0 7 7.42E+0 7 4.12E+0 7 1.45E+0 7 1.30E+0 7 1.19E+0 7 1.09E+0 7 1.12E+0 7 1.17E+0 7 1.58E+0 7 1.34E+0 7 1.16E+0 7 1.67E+0 7 1.95E+0 7 5.79E+0 7 1.96E+0 7 1.62E+0 7 39088 5.22E+0 7 9.24E+0 7 5.13E+0 7 1.80E+0 7 1.62E+0 7 1.48E+0 7 1.36E+0 7 1.39E+0 7 1.46E+0 7 1.97E+0 7 1.66E+0 7 1.45E+0 7 2.07E+0 7 2.43E+0 7 7.20E+0 7 2.44E+0 7 2.02E+0 7

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63 Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 39603 1.93E+0 8 3.41E+0 8 1.89E+0 8 6.65E+0 7 6.00E+0 7 5.46E+0 7 5.02E+0 7 5.14E+0 7 5.39E+0 7 7.28E+0 7 6.15E+0 7 5.35E+0 7 7.66E+0 7 8.98E+0 7 2.66E+0 8 9.02E+0 7 7.46E+0 7 40388 1.26E+0 8 2.23E+0 8 1.24E+0 8 4.34E+0 7 3.91E+0 7 3.56E+0 7 3.27E+0 7 3.35E+0 7 3.52E+0 7 4.75E+0 7 4.01E+0 7 3.49E+0 7 4.99E+0 7 5.86E+0 7 1.74E+0 8 5.88E+0 7 4.86E+0 7 40503 8.37E+0 7 1.48E+0 8 8.22E+0 7 2.89E+0 7 2.60E+0 7 2.37E+0 7 2.18E+0 7 2.23E+0 7 2.34E+0 7 3.16E+0 7 2.67E +0 7 2.32E+0 7 3.32E+0 7 3.90E+0 7 1.15E+0 8 3.91E+0 7 3.24E+0 7 Average, Emp irical 4.26E+0 7 7.53E+0 7 4.18E+0 7 1.47E+0 7 1.32E+0 7 1.20E+0 7 1.11E+0 7 1.14E+0 7 1.19E+0 7 1.61E+0 7 1.36E+0 7 1.18E+0 7 1.69E+0 7 1.98E+0 7 5.87E+0 7 1.99E+0 7 1.65E+0 7 Total, Emp irical 1.70E+0 9 2.71E+0 9 1.13E+0 9 3.08E+0 8 2.65E+0 8 1.45E+0 8 1.11E+0 8 9.08E+0 7 7.14E+0 7 9.64E+0 7 8.14E+0 7 7.09E+0 7 1.01E+0 8 9.91E+0 7 1.17E+0 8 3.98E+0 7 3.29E+0 7 Change, Emp irical 177.01% 55.52% 35.12% 90.14% 90.96% 92.02% 102.42% 104.83% 135.09% 84.40% 87.10% 143.00% 1 17.32% 296.20% 33.90% 82.67% Average, Model 4.26E+0 7 8.79E+0 7 5.60E+0 7 2.34E+0 7 2.12E+0 7 1.90E+0 7 1.71E+0 7 1.72E+0 7 1.75E+0 7 2.36E+0 7 1.99E+0 7 1.74E+0 7 2.48E+0 7 2.91E+0 7 8.32E+0 7 2.82E+0 7 2.33E+0 7 Total, Model 1.70E+0 9 3.52E+0 9 2.24E+0 9 9.37E+0 8 8.48E+0 8 7.60E+0 8 6.83E+0 8 6.90E+0 8 7.00E+0 8 9.45E+0 8 7.98E+0 8 6.95E+0 8 9.94E+0 8 1.16E+0 9 3.33E+0 9 1.13E+0 9 9.32E+0 8 Change, Model 206.56% 63.68% 41.84% 90.57% 89.58% 89.86% 101.00% 101.47% 135.09% 84.40% 87.10% 143.00% 117.09% 285.84% 33.90% 82.67% Model Relia nce 0.00% 22.88% 49.57% 67.07% 68.79% 80.98% 83.77% 86.83% 89.80% 89.80% 89.80% 89.80% 89.80% 91.48% 96.47% 96.47% 96.47%

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64 Table 16 Annual production values for wells in Las Animas County (natural gas only) Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 08280 4.2E+6 34.1E+6 12.0E+6 9.7E+6 794.9E+3 9.1E+6 171.0E+6 296.8E+6 295.9E+6 262.0E+6 249.9E+6 08908 423.5E+3 150.6E+6 54.5E+6 30.3E+6 24.0E+6 30.4E+6 20.1E+6 14.4E+6 44.6E+6 47.4E+6 76.6E+6 09386 264.3E+3 2 .9E+6 10.3E+6 31.5E+6 21.5E+6 17.9E+6 20.7E+6 61.6E+6 62.7E+6 72.1E+6 116.5E+6 09490 13.5E+6 18.2E+6 6.5E+6 5.2E+6 161.4E+3 23.9E+6 58.8E+6 108.1E+6 116.9E+6 134.5E+6 217.3E+6 09782 4.1E+6 8.4E+6 146.2E+3 1.6E+6 1.6E+6 980.9E+3 3.3E+6 6.0E+6 6.5E+6 7.5E+ 6 12.1E+6 09871 32.9E+6 131.8E+6 115.5E+6 95.0E+6 84.4E+6 51.5E+6 171.4E+6 314.7E+6 340.4E+6 391.8E+6 632.9E+6 09874 33.6E+6 154.1E+6 154.3E+6 126.0E+6 128.0E+6 78.1E+6 260.0E+6 477.5E+6 516.4E+6 594.5E+6 960.2E+6 09878 6.7E+6 22.8E+6 14.2E+6 9.6E+6 6.0 E+6 3.7E+6 12.2E+6 22.5E+6 24.3E+6 28.0E+6 45.2E+6 09885 164.3E+6 132.9E+6 98.0E+6 62.3E+6 30.4E+6 18.6E+6 61.8E+6 113.6E+6 122.8E+6 141.4E+6 228.4E+6 09898 211.8E+6 309.8E+6 308.3E+6 310.4E+6 151.7E+6 92.6E+6 308.1E+6 565.8E+6 612.0E+6 704.4E+6 1.1E+9 Average, Empirical 47.2E+6 96.6E+6 77.4E+6 68.2E+6 33.3E+6 20.3E+6 67.7E+6 124.3E+6 134.4E+6 154.7E+6 249.9E+6 Total, Emp irical 471.8E+6 965.5E+6 773.8E+6 681.7E+6 266.5E+6 81.3E+6 270.7E+6 372.8E+6 403.2E+6 309.4E+6 249.9E+6 Change, Emp irical 204.6% 8 0.1% 88.1% 48.9% 61.0% 332.8% 183.6% 108.2% 115.1% 161.5% Average, Model 47.2E+6 96.6E+6 77.4E+6 68.2E+6 44.9E+6 32.7E+6 108.8E+6 198.1E+6 214.2E+6 238.4E+6 367.7E+6 Total, Model 471.8E+6 965.5E+6 773.8E+6 681.7E+6 448.7E+6 326.8E+6 1.1E+9 2.0E+9 2.1E+9 2.4E+9 3.7E+9 Change, Model 204.6% 80.1% 88.1% 65.8% 72.8% 332.8% 182.1% 108.2% 111.3% 154.3% Model Reliance 0.0% 0.0% 0.0% 0.0% 40.6% 75.1% 75.1% 81.2% 81.2% 87.0% 93.2%

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65 Appendix B Annual Production Water Table 17 Annual pr oduced water generated for wells in Weld County Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 12459 14,532 10,122 3,024 12,264 29,568 26,334 18,774 24,822 19,740 17,850 126 4,452 32,634 35,070 89,040 19,530 16,968 12629 0 18,816 4,620 6,426 30,450 33,474 15,666 11,802 10,122 9,912 8,778 5,586 24,360 11,634 16,464 21,504 9,660 19794 0 0 0 0 0 0 0 0 0 0 0 0 0 11,718 26,975 10,492 6,808 20613 336 18,228 3,234 966 2,226 1,890 3,192 84 0 0 2,100 42,798 19,572 17,850 41,092 15,982 10,371 21028 11,508 21,462 21,168 19,110 13,356 20,118 28,560 19,278 4,956 76,398 34,608 26,796 11,508 38,304 88,178 34,295 22,255 21514 3,570 29,274 12,642 7,266 6,216 5,964 7,644 8,232 20,454 13,188 9,114 10,374 6,426 9,349 21,523 8,371 5,432 24914 0 9,114 16,842 8,736 5,964 1,638 0 0 0 0 0 0 0 0 0 0 0 25988 0 9,114 12,222 8,736 6,300 7,098 0 8,946 9,011 19,131 8,922 14,674 15,406 22,415 51,601 20,069 13,024 29021 0 1,764 2,898 8,946 2,730 16,884 2,352 2,823 2,844 6,038 2, 816 4,631 4,862 7,074 16,285 6,334 4,110 29022 0 16,044 5,334 4,620 2,730 16,842 0 0 0 0 0 0 0 0 0 0 0 30906 0 0 2,394 672 3,150 5,544 5,544 6,655 6,703 14,232 6,637 10,916 11,461 16,675 38,386 14,930 9,688 31642 1,132,530 519,876 188,496 77,826 117,516 86,226 86,226 103,50 4 104,25 7 221,348 103,22 7 169,77 4 178,25 1 259,343 597,022 232,202 150,68 2 32368 936,306 249,354 110,124 139,020 83,790 47,154 19,418 23,309 23,479 49,848 23,247 38,233 40,142 58,404 134,449 52,292 33,933 32457 44,940 169,134 127,596 160,356 279,132 157,084 64,688 77,651 78,215 166,059 77,443 127,36 7 133,72 7 194,563 447,895 174,201 113,04 4 32795 33,096 35,070 5,418 4,704 5,334 3,002 1,236 1,484 1,495 3,173 1,480 2,434 2,555 3,718 8,559 3,329 2,160 33361 150,486 189,630 71,652 68,586 83,511 46,997 19,353 23,232 23,401 49,682 23,169 38,106 40,009 58,210 134,002 52,118 33,821 34060 0 36,750 15,708 6,090 21,756 12,243 5,042 6,052 6,096 12,943 6,036 9,927 10,423 15,165 34,910 13,578 8,811 34062 4,998 321,300 51,576 2,688 7,560 4,254 1,75 2 2,103 2,118 4,498 2,097 3,450 3,622 5,270 12,131 4,718 3,062 34066 3,948 22,932 19,698 17,640 14,280 8,036 3,309 3,972 4,001 8,495 3,962 6,516 6,841 9,954 22,914 8,912 5,783 34068 10,584 90,174 24,654 7,644 10,920 6,145 2,531 3,038 3,060 6,496 3,030 4, 983 5,232 7,612 17,522 6,815 4,422 34509 30,954 163,128 34,650 4,704 14,532 8,178 3,368 4,043 4,072 8,645 4,032 6,631 6,962 10,129 23,318 9,069 5,885 36279 408,786 108,696 17,383 9,240 11,251 6,331 2,607 3,130 3,153 6,693 3,121 5,134 5,390 7,842 18,053 7 ,021 4,556 36468 565,152 165,312 130,830 69,542 84,676 47,652 19,623 23,556 23,727 50,374 23,492 38,637 40,566 59,021 135,870 52,844 34,292

PAGE 74

66 Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 36853 742,854 2,053,086 85,386 45,387 55,263 31,100 12,807 15,373 15,485 32,877 15,332 25,217 26,476 38,520 88,676 34,489 22,381 36855 772,674 2,929,794 117,642 62,532 76,140 42,849 17,645 21,181 21,335 45,297 21,124 34,742 36,477 53,072 122,174 47,518 30,835 36856 646,212 2,248,932 94,500 50,231 61,162 34,420 14,174 17,014 17,138 36,386 16,969 27,908 29,302 42,632 98,141 38,170 24,770 37401 821,142 324,156 151,284 80,415 97,914 55,102 22,691 27,238 27,436 58,250 27,165 44,678 46,909 68,249 157,112 61,106 39,653 37728 600,054 308,910 57,876 30,764 37,458 21,080 8,681 10,420 10,496 22,284 10,392 17,092 17,946 26,110 60,106 23,377 15,170 37790 363,636 59,094 9,451 5,023 6,117 3,442 1,417 1,702 1,714 3,639 1,697 2,791 2,930 4,263 9,815 3,817 2,477 38169 396,774 76,650 12,258 6,516 7,934 4,465 1,839 2,207 2,223 4,720 2,201 3,620 3,801 5,530 12,730 4,951 3,213 38415 2 9,904 61,824 9,887 5,255 6,399 3,601 1,483 1,780 1,793 3,807 1,775 2,920 3,066 4,460 10,268 3,994 2,592 38416 48,174 92,064 14,723 7,826 9,529 5,363 2,208 2,651 2,670 5,669 2,644 4,348 4,565 6,642 15,290 5,947 3,859 39006 746,928 278,082 44,472 23,639 28 ,783 16,198 6,670 8,007 8,065 17,123 7,986 13,134 13,789 20,063 46,185 17,963 11,657 39008 820,554 295,512 47,259 25,121 30,587 17,213 7,088 8,509 8,571 18,197 8,486 13,957 14,654 21,320 49,080 19,089 12,387 39009 761,670 255,444 40,851 21,714 26,440 14, 879 6,127 7,355 7,409 15,729 7,335 12,064 12,667 18,429 42,425 16,501 10,708 39010 676,494 245,532 39,266 20,872 25,414 14,302 5,890 7,070 7,121 15,119 7,051 11,596 12,175 17,714 40,779 15,860 10,292 39088 1,043,826 952,440 152,317 80,964 98,583 55,478 2 2,846 27,424 27,624 58,648 27,351 44,983 47,229 68,715 158,186 61,524 39,924 39603 865,998 790,181 126,368 67,171 81,788 46,027 18,954 22,752 22,918 48,657 22,691 37,320 39,183 57,009 131,237 51,042 33,123 40388 717,444 654,632 104,691 55,648 67,758 38,1 31 15,703 18,849 18,986 40,310 18,799 30,918 32,461 47,229 108,724 42,286 27,441 40503 517,818 472,484 75,561 40,164 48,905 27,521 11,333 13,605 13,703 29,094 13,568 22,315 23,429 34,088 78,472 30,520 19,805 Average Empiric al 348,097 317,622 50,795 27,0 00 32,876 18,501 7,619 9,146 9,212 19,558 9,121 15,001 15,750 22,915 52,752 20,517 13,314 Total, Emp iric al 13,923,88 2 11,434,37 4 1,371,46 8 567,000 657,510 222,012 76,188 73,164 55,272 117,348 54,726 90,006 94,500 114,576 105,504 41,034 26,628 Change, Emp iric al 91.25% 15.99% 53.15% 121.76% 56.28% 41.18% 120.04 % 100.73 % 212.31% 46.64% 164.47 % 104.99 % 145.49% 230.21% 38.89% 64.89% Average Model 348,097 357,603 51,649 31,876 40,078 25,006 12,211 14,271 14,140 30,020 14,000 23,026 24,175 34,834 80,140 31,16 9 20,226 Total, Model 13,923,88 2 14,304,11 1 2,065,95 7 1,275,02 5 1,603,12 0 1,000,26 0 488,44 4 570,85 4 565,59 2 1,200,80 8 560,00 5 921,02 1 967,00 7 1,393,36 5 3,205,58 9 1,246,76 0 809,05 4 Change, Model 102.73% 14.44% 61.72% 125.73% 62.39% 48.83% 116.87 % 99.08% 212.31% 46.64% 164.47 % 104.99 % 144.09% 230.06% 38.89% 64.89%

PAGE 75

67 Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 PY 12 PY 13 PY 14 PY 15 PY 16 PY 17 Model Reliance 0.00% 20.06% 33.62% 55.53% 58.99% 77.80% 84.40% 87.18% 90.23% 90.23% 90.23% 90.23% 90.23% 91.78% 96.71% 96.71% 96.71%

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68 Table 18 Annual produced water gen erated per well in Las Animas County Well API PY 1 PY 2 PY 3 PY 4 PY 5 PY 6 PY 7 PY 8 PY 9 PY 10 PY 11 08280 71,484 348,600 293,454 207,270 0 129,780 1,927,254 1,967,280 1,499,988 999,222 860,748 08908 0 1,303,596 1,289,358 2,559,984 1,380,120 743,484 83 0,676 890,526 1,395,198 1,828,302 1,113,135 09386 69,174 3,250,800 8,685,978 7,963,998 7,287,798 8,124,102 8,620,374 7,070,112 97,314 137,924 83,973 09490 8,264,550 15,588,300 11,479,986 12,159,420 1,154,580 366,996 988,554 1,058,127 318,944 452,040 275, 218 09782 3,461,472 13,839,588 226,380 0 0 0 0 0 0 0 0 09871 594,216 1,555,890 1,212,498 1,246,560 830,424 1,312,140 1,732,852 1,854,808 559,081 792,389 482,434 09874 675,318 1,415,064 986,454 1,023,750 1,072,554 1,694,726 2,238,106 2,395,622 722,095 1, 023,429 623,099 09878 145,362 396,270 312,438 299,460 127,512 201,480 266,080 284,807 85,847 121,672 74,078 09885 348,516 101,598 57,624 59,598 24,043 37,990 50,170 53,701 16,187 22,942 13,968 09898 6,255,522 6,955,704 9,784,656 11,206,818 4,521,020 7,1 43,594 9,434,045 10,098,002 3,043,767 4,313,947 2,626,483 Average, Empirical 1,988,561 4,475,541 3,432,883 3,672,686 1,481,624 2,341,091 3,091,715 3,309,306 997,500 1,413,762 860,748 Total, Emp irical 19,885,614 44,755,410 34,328,826 36,726,858 11,852,988 9,364,362 12,366,858 9,927,918 2,992,500 2,827,524 860,748 Change, Emp irical 225.1% 76.7% 107.0% 40.3% 158.0% 132.1% 107.0% 30.1% 141.7% 60.9% Average, Model 1,988,561 4,475,541 3,432,883 3,672,686 1,639,805 1,975,429 2,608,811 2,567,299 773,842 969,18 7 615,314 Total, Model 19,885,614 44,755,410 34,328,826 36,726,858 16,398,051 19,754,291 26,088,111 25,672,985 7,738,421 9,691,866 6,153,135 Change, Model 225.1% 76.7% 107.0% 44.6% 120.5% 132.1% 98.4% 30.1% 125.2% 63.5% Model Reliance 0.0% 0.0% 0.0% 0. 0% 27.7% 52.6% 52.6% 61.3% 61.3% 70.8% 86.0%

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69 Appendix C Identified Chemicals In the following table 0 signifies that the chemical is not part of that category, while 1 signifies it is part of the category In the Unknown category, 2 (green chemicals in Table 10 ) represents chemicals that use substitute chemicals and 3 (yellow chemicals in Table 10 ) mean that a chemical was unknown and could not be identified through any m eans employed. Italicized CAS numbers reference the CAS numbers for the substitute chemicals. The following table is organized by unknown then by alphabetical order. Table 19 All 184 chemicals detected in all 50 wells CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC 3RD PARTY ADDITIVE 0 0 3 0 INORGANIC BASE 0 0 3 1 NO HAZARDOUS INGREDI ENTS 0 0 3 0 NO MSDS INGREDIENTS (FRICTION REDUCER) 0 0 3 0 NONHAZARDOUS 0 0 3 0 NON IONIC SURFACTANT 0 0 3 0 ORGANIC POLYOL 0 0 3 0 ORGANIC SULFUR COMPO UND 0 0 3 0 POLYETHER 0 0 3 0 PROPRIETARY COMPONEN T, BIOCIDE 0 0 3 0 PROPRIETARY COMPONEN T, SURFACTANT 0 0 3 0 TRADE SECRET 0 0 3 0 ALKYL AMINE SURFACTA NT 0 0 3 0 ALKYLENE OXIDE BLOCK POLYMER 0 0 3 0 AMINE SALTS 0 0 3 0 AMMONIUM SALT 0 0 3 0 AMPHOTERIC SURFACTAN T 0 0 3 0 ANTIFOAM 0 0 3 0 APATITE 64476 38 6 0 0 3 1 BENTONITE, BENZYL(HY DROGENATED TALLOW ALKYL) DIMETHYLAMMON IUM STEARATE COMPLEX 121888 68 4 0 0 3 0 BIOTITE 1302 27 8 0 0 3 1

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70 CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC CARBOXYMETHYL GUAR GUM, SODIUM SALT 39346 76 4 0 0 3 0 ENZYME 0 0 3 0 HALOALKYL HETEROPOLY CYCLE SALT 0 0 3 0 N PROPANOL ZIRCONATE 0 0 3 0 OXYALKYLATED FATTY A CID 0 0 3 0 POLYOXYALKYLENES SUR FACTANT 0 0 3 0 POLYQUATERNARY AMINE 0 0 3 0 QUATERNARY AMINE 0 0 3 0 QUATERNARY AMMONIUM COMPOUNDS, BIS(HYDROGENATED TAL LOW ALKYL)DIMETHYL, SALTS WITH MONTMORIL LONITE 68911 87 5 0 0 3 0 QUATERNARY AMMONIUM COMPOUNDS, BIS(HYDROTREATED TAL LOW ALKYL)DIMETHYL, SALTS WITH BENTONITE 68953 58 2 0 0 3 0 ZIRCONIUM COMPLEX 0 0 3 0 ZIRCONIUM SOLUTION 0 0 3 0 ALCOHOL AMINE 102 71 6 0 0 2 0 ALDEHYDE 50 00 0 0 0 2 0 ALKOXYLATED AMINE 68155 27 1 0 0 2 0 AMIDE 67700 97 4 0 0 2 0 AROMATIC ALDEHYDE 100 52 7 0 0 2 0 CLAY 12173 60 3 0 0 2 1 EDTA/COPPER CHELATE 0 0 2 0 ETHOXYLATED ALCOHOL 68439 45 2 0 0 2 0 ETHOXYLATED AMINE 61791 26 2 0 0 2 0 ETHOXYLATED DECYL AL COHOL 68439 46 3 0 0 2 0 ETHOXYLATED FATTY AC ID 61791 26 2 0 0 2 0 FATTY ACID TALL OIL AMIDE 61790 12 3 0 0 2 0 FORMALDEHYDE AMINE R ESIN 9003 35 4 0 0 2 0 GUAR GUM DE RIVATIVE 74299 50 6 0 0 2 0 INORGANIC SALT 7647 14 5 0 0 2 1 N PROPYL ZIRCONATE 0 0 2 0 POLYACRYLATE 79 10 7 0 0 2 0 POLYSACCHARIDE 33404 34 1 0 0 2 0 QUATERNARY AMMONIUM SALT 122 18 9 0 0 2 0 SURFACTANTS 67 63 0 0 0 2 0 VARIOUS OXIDES AND T RACE EL EMENTS (FE2O3, CAO, AND MGO) ARE TH E LARGEST FRACTIONS 1309 37 1 0 0 2 1 2,3 DIHYDROXYPROPYL TRIMETHYLAMMONIUM CH LORIDE 34004 36 0 0 0 0 0 3 CHLORO 2 HYDROXYPR OPYL TRIMETHYLAZANIUM;CHL ORIDE 3327 22 8 0 0 0 0

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71 CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC 1 (BENZYL)QUINOLINIU M CHLORIDE 15619 48 4 0 0 0 0 1,2,3 TRIMETHYLBENZE NE 526 73 8 1 0 0 0 1,2,4 TRIMETHYLBENZE NE 95 63 6 1 1 0 0 2,2 DIBROMO 3 NITRIL OPROPIONAMIDE 10222 01 2 1 1 0 0 2 AMINE 2 METHYL PRO PANOL 124 68 5 1 1 0 0 2 BROMO 3 NITRILOPRO PIONAMIDE 1113 55 9 0 0 0 0 2 BUTOXYETHANOL 111 76 2 1 1 0 0 2 ETHYLHEXANOL 104 76 7 1 0 0 0 3,4,4 TRIMETHYLOXAZO LIDINE 75673 43 7 1 0 0 0 4,4 DIMETHYLOXAZOLID INE 51200 87 4 1 1 0 0 4 NONYLPHENYL 127087 87 0 0 0 0 0 ACETIC ACID 64 19 7 1 1 0 0 ACETIC ANHYDRIDE 108 24 7 1 1 0 0 ALKYL DIMETHYL BENZY L AMMONIUM CHLORIDE 68424 85 1 0 0 0 0 ALKYL PYRIDINE BENZY L QUATERNARY AMMONIUM CHLORIDE 68909 18 2 0 0 0 0 ALUMINUM OXIDE 1344 28 1 0 0 0 1 AMINES, COCO ALKYL, ETHOXYLATED 61791 14 8 0 0 0 0 AMINES, TALLOW ALKYL ETHOXYLATED 61791 26 2 0 0 0 0 AMMONI UM ACETATE 631 61 8 1 1 0 0 AMMONIUM CHLORIDE 12125 02 9 1 0 0 1 AMMONIUM DIHYDROGEN PHOSPHATE 7722 76 1 0 0 0 1 AMMONIUM HYDROXIDE 1336 21 6 0 0 0 1 AMMONIUM PERSULFATE 7727 54 0 0 0 0 1 AMMONIUM PHOSPHITE 13446 12 3 0 0 0 1 BORATE 7550 67 7 0 0 0 1 CALCITE 471 34 1 0 0 0 0 CALCIUM CHLORIDE 10043 52 4 0 0 0 1 CHLOROUS ACID, SODIU M SALT 7758 19 2 0 0 0 1 CHOLINE CHLORIDE 67 48 1 1 1 0 0 CINNAMALDEHYDE 104 55 2 1 0 0 0 CITRIC ACID 77 92 9 1 1 0 0 COBALT ACETATE 71 48 7 1 0 0 0 CRYSTALLINE SILIC A, QUARTZ 14808 60 7 0 0 0 1 DIBROMOACETONITRILE 3252 43 5 1 1 0 0 DIDECYL DIMETHYL AMM ONIUM CHLORIDE 111 42 2 1 0 0 0 DIETHYLENETRIAMINE 111 40 0 1 1 0 0 DINONYPHENYL 9014 93 1 0 0 0 0

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72 CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC DISODIUM ETHYLENE DI AMINEDIACETATE 38011 25 5 0 0 0 0 EO C7 9 IS O, C8 RICH ALCOHOLS 78330 19 5 0 0 0 0 EO C9 11 ISO, C10 RI CH ALCOHOLS 78330 20 8 0 0 0 0 ETHANOL 64 17 5 1 1 0 0 ETHOXYLATED BRANCHED C13 ALCOHOL 78330 21 9 0 0 0 0 ETHYLENE GLYCOL 107 21 1 1 1 0 0 FATTY ACIDS 0 0 0 0 FATTY ACIDS, TALL OI L 61790 12 3 0 0 0 0 FORMALDEHYDE;2 METHY LOXIRANE;(1E,3E) 4,5,5 TRIMETHYLHEXA 1,3 DIEN 1 OL 29316 47 0 0 0 0 0 FORMALDEHYDE;2 METHY LOXIRANE;4 NONYLPHENOL;OXIRANE 63428 92 2 0 0 0 0 FORMIC ACID 64 18 6 1 1 0 0 GLUTARALDEHYDE 111 30 8 1 1 0 0 GLYCERINE 56 81 5 1 1 0 0 GOETHITE 1310 14 1 0 0 0 1 GUAR GUM 9000 30 0 0 0 0 0 HEAVY ALIPHATIC PETR OLEUM NAPHTHA SOLVENT 64742 96 7 0 0 0 0 HEAVY AROMATIC PETRO LEUM NAPHTHA 64742 94 5 0 0 0 0 HEAVY HYDROTREATED P ETROLEUM NAPHTHA 64742 48 9 0 0 0 0 HEXAMETHYLENETETRAMI N E 100 97 0 1 1 0 0 HYDRATED MAGNESIUM S ILICATE (TALC) 14807 96 6 0 0 0 1 HYDROCHLORIC ACID 7641 01 0 1 0 0 1 HYDROTREATED LIGHT P ETROLEUM DISTILLATE 64742 47 8 0 0 0 0 HYDROTREATED MEDIUM PETROLEUM DISTILLATES 64742 46 7 0 0 0 0 ISOPROPANOL 67 63 0 0 1 0 0 ISOTRIDECANOL, ETHOX YLATED (TDA 6) 9043 30 5 0 0 0 0 LACTIC ACID 50 21 5 0 0 0 0 LAURY ALCOHOL ETHOXY LATE 68551 12 2 0 0 0 0 LIGHT AROMATIC PETRO LEUM NAPHTHA SOLVENT 64742 95 6 0 0 0 0 MAGNESIUM OXIDE 1309 48 4 0 0 0 1 MAGNESIUM PEROXIDE 14452 57 4 0 0 0 1 MESITYLENE 108 67 8 1 1 0 0 METHANOL 67 56 1 1 1 0 0 METHYL ISOBUTYL KETO NE 108 10 1 1 1 0 0 NAPHTHALENE 91 20 3 1 1 0 0 NAPHTHENIC ACID ETHO XYLATE 68410 62 8 0 0 0 0

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73 CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC N DIMETHYL FORMAMIDE 68 12 2 1 1 0 0 NITRILOTRIACETATE, T RISODIUM SAL T (NTA) 5064 31 3 0 1 0 0 NITROGEN 7727 37 9 1 0 0 1 OLEFIN 64743 02 8 0 0 0 0 ORGANIC SULFONIC ACI D 27176 87 0 1 1 0 0 OXIRANE, 2 METHYL POLYMER WITH OXIRANE MONODECYL ETHER 37251 67 5 0 0 0 0 PHENOL/FORMALDEHYDE RESIN 9003 35 4 0 0 0 0 POLY(OXY 1,2 ETHANEDIYL),.ALP HA. TETRADECYL .OMEGA. H YDROXY 27306 79 2 0 0 0 0 POLY(TETRAFLUOROETHY LENE) 9002 84 0 0 0 0 0 POLYETHYLENE GLYCOL 25322 68 3 0 0 0 0 POLYOXYALKYLENES 68951 67 7 0 0 0 0 POTASSIUM CARBONATE 584 08 7 0 0 0 0 POTASSIUM HYDROXIDE 1310 58 3 0 0 0 0 POTASSIUM PERSULFATE 7727 21 1 0 0 0 1 PROPANOL 71 23 8 1 1 0 0 PROPARGYL ALCOHOL 107 19 7 1 1 0 0 PROPRIETARY SESQUIOL ATE 8007 43 0 0 0 0 0 PROPYLENE GLYCOL 57 55 6 1 1 0 0 QUATERNARY AMMONIUM COMPOUND 122 18 9 0 0 0 0 SILICA, AMORPHOU S FUMED 7631 86 9 0 0 0 1 SODIUM BICARBONATE 144 55 8 0 0 0 0 SODIUM BROMIDE 7647 15 6 0 0 0 1 SODIUM CHLORIDE 7647 14 5 0 0 0 1 SODIUM ERYTHORBATE 6381 77 7 0 1 0 0 SODIUM HYDROXIDE 1310 73 2 0 0 0 1 SODIUM HYDROXYACETAT E 2836 32 0 0 0 0 0 SODIUM HYPOCHLORITE 7681 52 9 0 0 0 1 SODIUM IODIDE 7681 82 5 0 0 0 1 SODIUM LACTATE 72 17 3 0 0 0 0 SODIUM PERBORATE TET RAHYDRATE 10486 00 7 0 0 0 1 SODIUM PERSULFATE 7775 27 1 0 0 0 1 SODIUM SULFATE 7757 82 6 0 0 0 1 SODIUM;PROP 2 ENAMID E;PROP 2 ENOATE;P ROP 2 ENOIC ACID 62649 23 4 0 0 0 0 SORBITAN MONOOLEATE POLYOXYETHYLENE DERIVATIVE 9005 65 6 0 0 0 0 SORBITAN, MONO 9 OCT ADECENOATE, (Z) 1338 43 8 0 0 0 0 SOYBEAN OIL METHYL E STER 67784 80 9 0 0 0 0 STYRENE ACRYLIC COPO LYMER 25085 34 1 0 0 0 0

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74 CHEMICAL CAS NUMBER IN TRACI IN USETOX UNKNOWN INORGANIC SUCROSE 57 50 1 0 1 0 0 TALL OIL ACID DIETHA NOLAMIDE 68155 20 4 0 0 0 0 TERPENES AND TERPENO IDS 68956 56 9 0 0 0 0 TERPENES AND TERPENO IDS, SWEET ORANGE OIL 68647 72 3 0 0 0 0 TERT BUTYL HYDROPERO XIDE 75 91 2 1 1 0 0 TETRAMETHYL AMMONIUM CHLORIDE 75 57 0 1 1 0 0 TETRASODIUM ETHYLENE DIAMINE TETRAACETATE 64 02 8 1 1 0 0 THIOUREA POLYMER 68527 49 1 0 0 0 0 TRIETHANOLAMINE 102 71 6 1 1 0 0 TRIETHANOLAMINE ZIRC ONATE 101033 44 7 0 0 0 0 TRIETHYLENE GLYCOL 112 27 6 1 1 0 0 TRIMETHYLAMINE 75 50 3 1 1 0 0 TRIIS OPROPANOLAMINE 122 20 3 0 1 0 0 TRISODIUM ETHYLENEDI AMINETRIACETATE 19019 43 3 0 0 0 0 VINYLIDENE CHLORIDE METHYL ACRYLATE COPOLYMER 25038 72 6 0 0 0 0 WATER 7732 18 5 0 0 0 1 XYLENE 1330 20 7 1 0 0 0 ZIRCONIUM SODIUM HYD ROXY LACTATE COMPLEX 113184 20 6 0 0 0 0 ZIRCONIUM, ACETATE L ACTATE OXO AMMONIUM COMPLEXES 68909 34 2 0 0 0 0