EPA/601/R-14/003 l March 2015 l www.epa.gov/hfstudy



# Analysis of Hydraulic Fracturing Fluid

Data from the FracFocus Chemical

Disclosure Registry 1.0Analysis of Data from FracFocus 1.0 March 2015

ii 

### [This page intentionally left blank.]Analysis of Data from FracFocus 1.0 March 2015

iii 

# Analysis of Hydraulic Fracturing Fluid Data

from the FracFocus Chemical Disclosure Registry 1.0

U.S. Environmental Protection Agency

Office of Research and Development

Washington, DC

March 2015

EPA/ 601/R

- 14/003Analysis of Data from FracFocus 1.0 March 2015

iv 

# Disclaimer

This document has been reviewed in accordance with U.S. Environmental Protection Agency policy

and approved for publication. Mention of tra de names or commercial products

does not constitute endorsement or recommendation for use.

Preferred Citation : U

. S

. Environmental Protection Agency. 201 5

. Analysis of Hydraulic Fracturing Fluid

Data from the FracFocus Chemical Disclosure Registry 1.0

. Office of Research and Development,

Washington, DC. EPA/601/R

- 14/00 3

.Analysis of Data from FracFocus 1.0 March 2015

v 

# Table of Contents

Disclaimer

................................ ................................ ................................ ................................ ..................... iv

Table of Contents

................................ ................................ ................................ ................................ .......... v

List of Tables

................................ ................................ ................................ ................................ ............... vii

List of Figures

................................ ................................ ................................ ................................ ............... ix

Preface

................................ ................................ ................................ ................................ .......................... x

Authors and Contributors

................................ ................................ ................................ ............................ xi

Acknowledgements

................................ ................................ ................................ ................................ ...... xi

List of Acronyms

................................ ................................ ................................ ................................ .......... xii

Executive Summary

................................ ................................ ................................ ................................ ....... 1

1. Introduct ion

................................ ................................ ................................ ................................ ............. 6

Objective

................................ ................................ ................................ ................................ ....... 6

Background

................................ ................................ ................................ ................................ ... 6

2. Methodology for Data Extraction and Analysis

................................ ................................ ....................... 8

Database Development

................................ ................................ ................................ ................. 8

2.1.1. Source Data

................................ ................................ ................................ ........................... 8

2.1.2. Data Conversion and Extraction

................................ ................................ ............................ 9

2.1.3. Parsing Success

................................ ................................ ................................ ................... 10

Data Standardization and Quality Assurance

................................ ................................ ............. 12

2.2.1. Quality Assurance of Locational Data

................................ ................................ ................. 13

2.2.2. Addition of Geologic Information

................................ ................................ ....................... 14

2.2.3. Quality Assurance of Ingredients

................................ ................................ ........................ 15

Analyses

................................ ................................ ................................ ................................ ...... 19

2.3.1. Specific Criteria for Analyses

................................ ................................ ............................... 19

2.3.2. Calculations

................................ ................................ ................................ ......................... 25

3. Results

................................ ................................ ................................ ................................ .................... 27

Additive Ingredients

................................ ................................ ................................ .................... 32

3.1.1. Reported Frequency and Fluid Concentrations of Additive Ingredients

............................ 33

3.1.2. Additive Purposes

................................ ................................ ................................ ............... 39

3.1.3. Comparing Variability of Additive Ingredients in Selected Counties

................................ .. 39

Base Fluids

................................ ................................ ................................ ................................ ... 42

3.2.1. Use of Non

- Aqueous Fluids in Base Fluids

................................ ................................ .......... 43

3.2.2. Cumulative Total Water Volumes

................................ ................................ ....................... 46Analysis of Data from FracFocus 1.0 March 2015

vi 

### 3.2.3. Total Water Volumes per Disclosure

................................ ................................ .................. 49

3.2.4. Comparing Variability of Total Water Volumes in Selected Counties

................................ 51

3.2.5. Water Sources

................................ ................................ ................................ ..................... 54

Proppants

................................ ................................ ................................ ................................ .... 60

4. Conclusions

................................ ................................ ................................ ................................ ............ 62

References

................................ ................................ ................................ ................................ .................. 67

Glossary

................................ ................................ ................................ ................................ ....................... 71

Appendix A. Shale Basin Map

................................ ................................ ................................ ..................... 76

Appendix B. Chemical Families for Ingredients Listed as Confidential Business Information

.................... 77

Appendix C. Histograms of Hydraulic Fracturing Fluid Concentrations for Most Frequently Reported

Additive Ingredients

................................ ................................ ................................ ................................ .... 92

Appendix D. List of Operators

................................ ................................ ................................ ................... 112

Appendix E. Reporting Regulations for States with Data in the Project Database

................................ ... 129

Appendix F. Additive Purposes

................................ ................................ ................................ ................. 1 32

Appendix G. Most Frequently Reported Additive Ingredients for Five Selected Counties

...................... 134

Appendix H. Total W ater Volumes by County

................................ ................................ .......................... 142Analysis of Data from FracFocus 1.0 March 2015

vii 

# List of Tables

Table ES

- 1. State

- specific information on the number of unique disclosures with a fracture date

between January 1, 2011, and February 28, 2013; total water volumes reported per

disclosure; and the number of unique additive ingredients reported per disclosure

........... 3

Table ES

- 2. Most frequently reported additive ingredients in disclosures associated with oil wells

and in disclosures associated with gas wells

................................ ................................ ......... 4

Table 1. Number of parsed, partially parsed, and unparsed disclosures, summarize d by state

....... 11

Table 2. Number and percentage of disclosures that had data successfully parsed from the

well header and ingredients tables and that met the primary QA criteria

......................... 13

Table 3. Examples of ingredient name standardization

................................ ................................ .... 16

Table 4. Additive ingredients reported as confidential business information (CBI), summarized

by state

................................ ................................ ................................ ................................ . 1 8

Table 5. Filters, QA criteria, disclosures, and ingredient records associated with analyses

presented in this report

................................ ................................ ................................ ....... 2 1

Table 6. Number and percentage of u nique disclosures in the project database with a fracture

date between January 1, 2011, and February 28, 2013

................................ ....................... 29

Table 7. Number of unique additive ingredients per di sclosure, summarized by state

.................... 34

Table 8. Twenty most frequently reported additive ingred ients in oil disclosures, ranked by

frequency of occurrence

................................ ................................ ................................ ...... 35

Table 9. Twenty most frequently reported additive ingredients in gas disclosures, rank ed by

frequency of occurrence

................................ ................................ ................................ ...... 36

Table 10. Frequently reported additive ingredients and commonly listed p urposes for additives

that contain the ingredients

................................ ................................ ................................ 40

Table 11. Counties selected to illustrate diversity in additiv e ingredients at small scales

.................. 41

Table 12. Comparison of 20 most frequently reported additive ingred ients among selected

counties

................................ ................................ ................................ ................................ 42

Table 13. Non

- aqueous ingredients reported in base fluids

................................ ............................... 4 4

Table 14. Use of non

- aqueous ingredients in bas e fluids, summarized by state

................................ 45

Table 15. Total w ater volumes, summarized by state

................................ ................................ ......... 48

Table 16. Total w ater volumes for selected counties in approximately the 90th percentile of

disclosures

................................ ................................ ................................ ............................ 53

Table 17. Number of disclosures having terms suggestive of wat er sources, summarized

by state

................................ ................................ ................................ ................................ . 55

Table 18. Median maximum fluid concentrations of water b y source, s ummarized by state

............ 58Analysis of Data from FracFocus 1.0 March 2015

viii 

### Table 19. Ten most frequently reported proppant ingredients, ranked by frequency

of occurrence

................................ ................................ ................................ ....................... 61

Table B

- 1. Chemical famili es for CBI ingredient records

................................ ................................ ....... 78

Table B

- 2. Most frequently reported chemical families among CBI ingredients and their most

commonly listed purposes

................................ ................................ ................................ ... 91

Table D

- 1. Disclosures per state, summarized by well operator

................................ ......................... 112

Table E

- 1. Reporting regulations for states with data in the project database

................................ .. 129

Table F

- 1. Number of disclosures, summarized by additive purpose categorie s

............................... 132

Table G

- 1. Twenty most frequently reported additive ingredients in Andrews County, Texas,

ranked by frequency of occurrence

................................ ................................ ................... 134

Table G

- 2. Twenty most frequently reported additive ingredients in Bradford County,

Pennsylvania , ranked by fre quency of occurrence

................................ ............................ 135

Table G

- 3. Twenty

- one most frequently reported additive ingredients in Dunn County, North

Dakota , ranked by frequency of occurrence

................................ ................................ ...... 136

Table G

- 4. Twenty most frequently reported additive ingredients in Garfield County, Colorado

,

ranked by frequency of occurrence

................................ ................................ ................... 138

Table G

- 5. Twenty most frequently reported additive ingredients in Kern County, California

,

ranked by frequency of occurrence

................................ ................................ ................... 140

Table H

- 1. Total w ater v olumes, summarized by county

................................ ................................ .... 142Analysis of Data from FracFocus 1.0 March 2015

ix 

# List of Figures

Figure 1. Exa mple FracFocus 1.0 disclosure

................................ ................................ .......................... 9

Figure 2. Geographic distribution of disclosures in the project database

................................ .......... 27

Figure 3. Geographic distribution of d isclosures by production type

................................ ................. 30

Figure 4. Distribution of fracture dates in the project database

................................ ........................ 31

Figure 5. Cumulative total water volumes , summarized by county

................................ ................... 47

Figure 6. Median total water volumes per dis closure, summarized by county

................................ .. 50

Figure 7. Variability in reported total water volumes per disclosure, as measured by the

difference betwe en t he 5th and 95th percentiles

................................ ............................... 51

Figure A

- 1. Shale basins map

................................ ................................ ................................ .................. 7 6Analysis of Data from FracFocus 1.0 March 2015

x 

# Preface

The U.S. Environmental Protection Agency (EPA) is conducting a Study of the Potential Impacts of

Hydraulic Fracturing for Oil and Gas on Drinking Water Resources . The study is based u pon an extensive

review of the literature; results from EPA research projects; and technical input from state, industry, and

non

- governmental organizations

, as well as the public and other stakeholders. A series of technical

roundtables and in

- depth techni cal workshops were held to help address specific research questions

and to inform the work of the study.

In Fiscal Year 2010, Congress urged the EPA to examine the relationship between hydraulic fracturing

and drinking water resources in the United States . The EPA’s Plan to Study the Potential Impacts of

Hydraulic Fracturing on Drinking Water Resources was reviewed by the agency’s Science Advisory Board

(SAB) and issued in 2011. The Study of the Potential Impacts of Hydraulic Fracturing on Drinking Water

R esources : Progress Report , detailing the EPA’s research approaches and next steps

, was released in late

2012 and followed by a consultation with individual experts convened under the auspices of the SAB.

This report

, Analysis of Hydraulic Fracturing Fluid Data from the FracFocus Chemical Disclosure Registry

1.0

, is the product of one of the research projects conducted as part of the EPA’s study. It has

undergone independent, external peer review, which was conducted through the Eastern Research

Group, Inc. All peer review comments were considered in the report’s development. The report has also

been reviewed in accordance with agency policy and approved for publication.

The EPA is writing a state

- of

- the

- science assessment that integrates a broad review of e xisting literature,

results from peer

- reviewed EPA research products (including this report), and information gathered

through stakeholder engagement efforts to answer the fundamental research questions posed for each

stage of the hydraulic fracturing wate r cycle:

 Water Acquisition : What are the possible impacts of large volume water withdrawals from

ground and surface waters on drinking water resources?

 Chemical Mixing : What are the possible impacts of surface spills on or near well pads of

hydraulic fracturing fluids on drinking water resources?

 Well Injection : What are the possible impacts of the injection and fracturing process on drinking

water resources?

 Flowback and Produced Water : What are the possible impacts of surface spills on or near well

p ads of flowback and produced water on drinking water resources?



###  Wastewater Treatment and Waste Disposal : What are the possible impacts of inadequate

treatment of hydraulic fracturing wastewaters on drinking water resources?

The state

- of

- the

- science assessm ent is not a human health or an exposure assessment, nor is it designed

to evaluate policy options or best management practices. As a Highly Influential Scientific Assessment,

the draft assessment report will undergo public comment and a meaningful and tim ely peer review by

the SAB to ensure all information is high quality.Analysis of Data from FracFocus 1.0 March 2015

xi 

# Authors and Contributors

Susan Burden, US EPA

Jill Dean, US EPA

Jonathan Koplos, The Cadmus Group, Inc. , under contract EP

- C

- 08

- 015

Claudia Meza

- Cuadra, Student Services Contractor for the US EPA under contract EP

- 13

- H

- 000054

Alison Singer, Student Services Contractor for the US EPA under contract EP

- 13

- H

- 000474

Mary Ellen Tuccillo, The Cadmus Group, Inc. , under contract EP

- C

- 08

- 015



# Acknowledgements

The EPA would like to acknowledg e the Ground Water Protection Council and the Interstate Oil and Gas

Compact Commission for providing data and information for this report. Assistance was provided by The

Cadmus Group, Inc., under contract EP

- C

- 08

- 015

. The contractors’ role did not include establishing

agency policy.Analysis of Data from FracFocus 1.0 March 2015

xii 

# List of Acronyms

API American Petroleum Institute

CASRN Chemical Abstracts Service Registry Number

CBI Confidential Business Information

CSV Comma

- Separated Values

EPA U.S. Environmental Protection Agency

GIS Geographi c Information System

GWPC Ground Water Protection Council

IOGCC Interstate Oil and Gas Compact Commission

MSDS Material Safety Data Sheet

PDF Portable Document Format

QA Quality Assurance

SEAB Secretary of Energy Advisory Board

TVD True Vertical Depth

XML Extensible Markup LanguageAnalysis of Data from FracFocus 1.0 March 2015

1 

# Executive Summary

H ydraulic fracturing has enabled oil and gas production to expand into areas of the United States

where production was once considered impractical. As production has increased, so have public

concerns about hydraulic fracturing and its potential effects on drinking water and the

environment. In response to public interest in the composition of hydraulic fracturing fluids, the

Ground Water Protection Council (GWPC) and the Interstate Oil and Gas Compact Commission

(IOGCC) developed the FracFocus Chemical Disc losure Registry (subsequently referred to as

“FracFocus”)

. FracFocus is a publicly accessible website ( www.fracfocus.org ) where oil and gas

production well operators can disclose information about the ingredients used in hydraulic

fracturing fluids at indi vidual wells. Although FracFocus was designed for local users, it provides an

opportunity to study the composition of hydraulic fracturing fluids nationwide.

This report analyzes data from more than 39,000 FracFocus disclosures provided to the U.S.

Environ mental Agency ( EPA ) by the GWPC in March 2013

. Each disclosure contained data for an

individual oil and gas production well

. Data on the composition of hydraulic fracturing fluids were

extracted from the disclosure s and summarized to address the following research questions from

the EPA’s Plan the Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources :

 What are the identities and quantities of chemicals used in hydraulic fracturing fluids, and

how might this composition vary at a g iven site and across the country?

 How much water is used in hydraulic fracturing operations, and what are the sources of

this water?

Data from this study will supplement information obtained from the published literature and other

sources being considered by the EPA in the preparation of the agency’s assessment of the potential

impacts of hydraulic fracturing for oil and gas on drinking water resources.

Disclosures analyzed for this report were submitted to FracFocus by well operators using the

FracFocus 1.0 format. 1 

### Data in the disclosures were extracted from individual portable document

format (PDF) files and compiled in a project database. 2 

### Information on fracture date, operator, well

identification and location, production type, true vertical depth, an d the total water volume used for

hydraulic fracturing were successfully ex tracted from 38,530 disclosures. Hydraulic fracturing fluid

composition data were extracted for 37,017 disclosures. Hydraulic fracturing fluid composition

data included trade names of additives, the purpose associated with each additive, and the identity

[i.e., chemical name and Chemical Abstract s Services Registry Number (CASRN)] and maximum

concentration of each ingredient in an additive and in the overall hydraulic fracturing flui d. The

content of the project database was influenced by the data conversion process (i.e., extracting data

1 FracFocus 2.0 became the exclusive disclosure mechanism in June 2013, which is past the timeframe of this study

(January 2011 to February 2013). More information on the FracFocus 1.0 and FracFocus 2.0 formats may be found in the

FracFocus 2.0 Operator Tra ining materials available at http://fracfocus.org/node/331 . In early 2015, the GWPC and the

IOGCC announced new features for FracFocus 3.0. More information on FracFocus 3.0 is available at

http://www.fracfocus.org/major

- improvements

- fracfocus

- announced

.

2 The project database and the accompanying Data Management and Quality Assessment Report are available at

http://www2.epa.gov/hfstudy/published

- scientific

- papers . The Data Management and Quality Assessment Report

describes the structure of the database, data fields, and quality assessment of the data.Analysis of Data from FracFocus 1.0 March 2015

2 

### from PDFs into the project database) as well a s the completeness and accuracy of data in the

original PDF disclosures. Reviews of data quality were conducted on the project database prior to

data analysis to ensure that the results of the analyses reflected the data contained in the PDF

disclosures, while identifying obviously invalid or incorrect data to exclude from analyses

.

Analyses were conducted on unique (i.e., non

- duplicate) disclosures with a fracture date between

January 1, 2011, and February 28, 2013 , that met appropriate quality assurance criteria for a given

analysis

. The disclosures identified well locations in 406 counties in 20 states a nd were reported by

428 well operators. True vertical depths ranged from approximately 2,900 feet to nearly 13,000

feet (5 th to 95 th percentile), with a median of just over 8,100 feet. Generally, well locations

represented by the disclosures were clustered in the northeast (mainly in and around

Pennsylvania), the west central portion of the country (from North Dakota and Wyoming through

Texas and Louisiana), and in California. Summary statistics performed on the entire dataset reflect

a greater co ntribution of data from states that are better represented in the project database than

others

— partly due to the locations of oil

- and gas

- bearing reservoirs, different state reporting

requirements, 3 

### and the success in extracting data from individual PDF d isclosures.

State

- specific data on the number of unique disclosures with a fracture date in the study time

period and summary statistics on total water volumes and additive ingredients per disclosure are

reported in Table ES

- 1. Ingredients reported in the disclosures were generally categorized in

analyses as either additive ingredients, base fluid s , or proppant s depending upon entries in the

trade name, purpose, and comments fields as well as the reported maximum ingredient

concentration in the hydraulic f racturing fluid. Additive ingredients included ingredients reported

for trade names (i.e., additives) that had purposes other than base fluid or proppant. The project

database contains 692 unique ingredients reported for additives, base fluids, and proppan ts.

Operators designated 11% of all ingredient records as confidential business information. One or

more ingredient s were claimed confidential in more than 70% of disclosures.

As shown in Table ES

- 1, the median number of additive ingredients per disclosure for the entire

dataset was 14 , with a range of 4 to 28 (5 th to 95 th percentile)

. The most commonly reported

additive ingredients were methanol, hydrochloric acid, and hydrotreated light petroleum distillates

( reported in 71 %, 65%, and 65% of disclosures , respectively ). Table ES

- 2 shows the occurrence and

median value of reported maximum concentration s in hydraulic fracturing fluid 4 

### for the most

frequently reported additive ingredients in disclosures associated with oil wells and in disclosure s

associat ed with gas wells. Among the entire data set, t he sum of the maximum hydraulic fracturing

fluid concentration for all additive ingredients report ed in a disclosure was less than 1% by mass in

approximately 80% of disclosures , and the median maximum hydraulic fracturing fluid

concentration was 0.43 % by mass

. Among proppants, quartz was the most common material

3 During the period of time studied in this report, six of the 20 states with data in the project database began requiring

operators to disclose chemicals used in hydraulic fracturing fluids to FracF ocus, t h ree states started requiring disclosure

to either FracFocus or the state, and five states required or began requiring disclosure to the state.

4 Well operators reported the maxi mum concentration of an ingredient in the additive and in the hydraulic fractur ing

fluid. Therefore, the median concentration values presented in this report represent the median value of the reported

maximum concentration s or the “median maximum concentration.”Analysis of Data from FracFocus 1.0 March 2015

3 

### reported (present in at least 98% of disclosures that identified proppants), with a median

maximum hydraulic fracturing fluid c oncentration of 10% by mass.

Base fluids described in the disclosures included water, water with non

- aqueous constituents (i.e.,

gases or hydrocarbons), and hydrocarbons only. More than 93% of the disclosures analyzed in the

study are inferred to use water as a base fluid, 5 

### with a median maximum concentration of 88% by

mass in hydraulic fracturing fluids. As shown in Table ES

- 1, t he median total water volume per

5 The determination of water used as a base fluid was based on disclos ures that included at least one water ingredient

with a maximum fluid concentration greater than or equal to 1% by mass. The 1% cutoff was chosen after considering the

median and 95th percentiles of maximum hydraulic fracturing fluid concentrations of freq uently reported additive

ingredients as well as the median maximum hydraulic fracturing fluid concentration of all ingredients per disclosure. Table ES

- 1. State

- specific information on the number of unique disclosures with a fracture date between January

1, 2011, and February 28, 2013; total water volumes reported per disclosure ; and the number of unique additive

ingredients reported per disclosure

.

State Number of

disclosures* Total water volume per disclosure

(gallons) † Number of additive ingredients

per disclosure §

Median 5 th

percentile 95 th

percentile Median 5th

percentile 95th

percentile

Alabama 55 37,691 23,602 51,651 10 10 10

Alaska 37 88,448 36,437 435,638 15 13 16

Arkansas 1,450 5,277,890 2,681,465 7,484,091 10 6 21

California 718 77,154 18,684 356,453 19 10 23

Colorado 4,938 463,659 103,906 4,327,068 13 5 23

Kansas 136 1,421,591 9,866 2,448,300 14 8 17

Louisiana 1,038 5,148,696 277,540 8,942,170 15 1 29

Michigan 15 33,306 15,722 15,127,125 19 10 29

Mississippi 4 9,173,624 4,322,108 12,701,054 14 11 23

Montana 213 1,469,839 216,578 3,197,594 16 9 38

New Mexico 1,162 172,452 22,130 2,851,323 21 7 31

North Dakota 2,254 2,019,513 557,740 3,685,402 15 4 33

Ohio 148 3,887,499 2,526,398 7,442,826 17 8 38

Oklahoma 1,909 2,578,947 114,870 8,288,041 12 5 30

Pennsylvania 2,483 4,184,936 1,092,739 7,475,493 10 4 18

Texas 18,075 1,413,287 26,006 7,407,116 15 4 30

Utah 1,429 303,424 35,070 1,056,654 17 7 23

Virginia 90 33,474 13,322 96,684 9 7 12

West Virginia 277 5,012,238 2,500,529 7,889,759 12 7 22

Wyoming 1,457 306,246 5,503 3,110,272 10 5 24

State Uncertain ‡ 162 2,770,090 80,067 6,945,958 15 5 27

Entire Dataset 38,050 1,508,724 29,526 7,196,702 14 4 28

* See Table 6 for notes on quality assurance criteria.

† See Table 15 for notes on quality assurance criteria.

§ See Table 7 for notes on quality assurance criteria.

‡ State location did not pass state locational quality assurance criteria (Section 2.2.1).Analysis of Data from FracFocus 1.0 March 2015

4 

### disclosure was approximately 1.5 million gallons , with a range of nearly 30,0 00 gallons to

approximately 7.2 million gallons (5 th to 95 th percentile ) . Non

- aqueous constituents (i.e., nitrogen,

carbon dioxide, and hydrocarbons ) were reported as base fluids or in combination with water as a

base fluid in fewer than 3% of disclosures. Twenty

- nine percent of disclosures in the project

database included information related to water sources. Some of these terms indicate d a condition

of water quality, such as “fresh,” rather than a specific ident ification of the source of the water (e. g.,

ground water, surface water ). T he most commonly reported source of water used for base fluid was

“fresh” (68% of disclosures with water source information)

.

Table ES

- 2. Most frequently reported additive ingredients in disclosures associated with oil wells and in disclosures

associated with gas wells

.

Oil Production Type Gas Production Type

EPA

standardized

chemical name * Number ( %)

of disclosures Median

concentration

in hydraulic

fracturing fluid

(% by mass) EPA

standardized

chemical name * Number ( %)

of disclosures Median

concentration

in hydraulic

fracturing fluid

(% by mass)

Methanol 12,484 (72%) 0.022 Hydrochloric

acid 12,351 (73%) 0.078

Distillates,

petroleum,

hydrotreated

light † 10,566 (61%) 0.087 Methanol 12,269 (72%) 0.0020

Peroxydisulfuric

acid,

diammonium

salt 10,350 (60%) 0.0076 Distillates,

petroleum,

hydrotreated

light † 11,897 (70%) 0.017

Ethylene glycol 10,307 (59%) 0.023 Isopropanol 8,008 (47%) 0.0016

Hydrochloric

acid 10,029 (58%) 0.29 Water † 7,998 (47%) 0.18

Guar gum 9,110 (52%) 0.17 Ethanol † 6,325 (37%) 0.0023

Sodium

hydroxide 8,609 (50%) 0.010 Propargyl

alcohol 5,811 (34%) 0.000070

Quartz † 8,577 (49%) 0.0041 Glutaraldehyde 5,635 (33%) 0.0084

Water † 8,538 (49%) 1.0 Ethylene glycol 5,493 (32%) 0.0061

Isopropanol 8,031 (46%) 0.0063 Citric acid 4,832 (28%) 0.0017

Potassium

hydroxide † 7,206 (41%) 0.013 Sodium

hydroxide 4,656 (27%) 0.0036

Glutaraldehyde 5,927 (34%) 0.0065 Peroxydisulfuric

acid,

diammonium

salt 4,618 (27%) 0.0045

* See Section 2.2.3 for a description of the standardization process.

† Chemical has a non

- normal distribution and the median may not represent the central tendency of the dataset as well as

the median of a normally distributed dataset.

Note: Analysis consi dered 34,675 disclosures and 676,376 ingredient records that met selected quality a ssurance criteria,

including: completely parsed; unique combination of fracture date and API well number; f racture date between January 1,

2011, and February 28, 2013; valid CASRN; and concentrations between 0 and 100%. Disclosures that did not meet quality

assurance criteria (3,855 disclosures) or other, query

- specific criteria were excluded from analysis.Analysis of Data from FracFocus 1.0 March 2015

5 

### Data extracted from disclosures submitted by oil and gas well operators to FracFocus 1.0 showed

that hydraulic fracturing fluids used between January 2011 and February 2013 generally contained

water as a base fluid, quartz as proppant, and various additive ingredients. Three additive

ingredients (methanol, hydrochloric acid, and hydrotreated light petroleum distillates) were

individually reported in more than 65% of oil and gas disclosures, alt hough 692 unique ingredients

were identified. The project database and the summary statistics presented in this report provide

useful insights into the chemical composition of hydraulic fracturing fluids and water volumes used

for hydraulic fracturing, whi ch are important factors to consider when assessing potential impacts

to drinking water resources from hydraulic fracturing

.Analysis of Data from FracFocus 1.0 March 2015

6 

# 1. Introduction

Objective

The objective of this study was to analyze data contained in the FracFocus Chemical Disclosure

Registry 1. 0 to address the following research questions from the EPA’s Plan to Study the Potential

Impacts of Hydraulic Fracturing on Drinking Water Resources (2011):

 What are the identities and quantities of chemicals used in hydraulic fracturing fluids, and

how might this composition vary at a given site and across the country?

 How much water is used in hydraulic fracturing operations, and what are the sources of

this water?

FracFocus (www.fracfocus.org) is a national hydraulic fracturing chemical registry developed by

the Ground Water Protection Council (GWPC) and the Interstate Oil and Gas Compact Commission

(IOGCC). Oil and gas production well operators disclose to FracFocus the composition of hydraulic

fracturing fluids used at individual oil and gas production wells across the United States

. Disclosures (i.e., the information submitted for a single well) evaluated in this report had fracture

dates between January 1, 2011, and February 28, 2013, and were uploaded by operators to

FracFocus prior to March 1, 2013. Data extracted from the disclosures included fracture date,

operator, well identification and location, production type (i.e., oil or gas), true vertical depth, total

water volume, and hydraulic fracturing fluid composition

. Hydraulic fracturing fluid composition

data include trade names of additives, the purpose associated with each additive, and the identity

[i.e., chemical name and Chemical Abstracts Services Registry Number (CASRN)] and maximum

concentration of each ingredient in an additive and in the overall hydraulic fracturing fluid.

Chemical and water use in hydraulic fracturing fluids was summarized, with some context provided

by a limited literature review. Data from this study will supplement information obtained from the

published literature and other sources being considered by the EPA in the preparation of the

agency’s assessment of the potential impacts of hydraulic fracturing for oil and gas on drinking

water resources.



## Backgroun d

Hydraulic fracturing is a technique used to enable or enhance both conventional and

unconventional production of oil and gas from hydrocarbon-containing rock formations. The

practice involves the injection of fluids under pressures great enough to fracture the formation.

Fractures resulting from the process are held open using proppants, which allows oil and gas to

flow from within the rock to the production well. Hydraulic fracturing fluids are composed of a base

fluid, proppants, and additives. An additive is added to the hydraulic fracturing fluid to change the

fluid’s properties (e.g., viscosity, pH) and can be a single chemical or a mixture of chemicals. The

choice of additives in fracturing fluids is influenced by many factors, including the geology of the

target rock formation to be hydraulically fractured, the pressure and temperature conditions in the

target formation, operator preference, and potential interactions between chemicals in the

fracturing fluid (NYSDEC, 2011; Rahim et al., 2013). Although hydraulic fracturing has been used to

increase hydrocarbon production since the 1940s (GWPC and IOGCC, 2014), recent applications ofAnalysis of Data from FracFocus 1.0 March 2015

7 

### hydraulic fracturing with directional drilling techniques have expanded domestic production of oil

and gas into formations where production was impractical at one time.

In the late 2000s, the public became increasingly interested in understanding the chemical

composition of hydraulic fracturing fluids . The GWPC and the IOGCC responded to the public’s

interest by developing a national hydraulic fracturing chemical registry, FracFocus. Oil and gas well

operators began to voluntarily upload information on the composition of hydraulic fracturing fluids

used at individual production wells to FracFocus 1.0 in April 2011. 6 

### At that time, each disclosure

included information about the well (e.g., operator name, well identification and location, total

water volume, production type) and hydraulic fracturing fluid composition. Hydraulic fracturing

fluid composition information inclu de d the identity and concentration of ingredients used as base

fluids, proppants, and additives. The public could search FracFocus 1.0 for disclosures in their local

area, and search results were provided in the form of an individual portable document format

(PDF) file for a specific well. In late 2012, the GWPC and the IOGCC launched FracFocus 2.0, which

has expanded search parameters for the public and mechanisms, such as dropdown menus and

automatic formatting, for certain fields to improve consistency and completeness of reporting by

operators. FracFocus 2.0 became the exclusive submission method in June 2013. In early 2015, the

GWPC and the IOGCC announced additional updates to FracFocus that include providing public

extraction of data in a machine readable format and verification of CASRNs. 7



### Although FracFocus was designed to meet local informational needs, the large number of entries in

the registry provides insights into the composition of hydraulic fracturing fluids at county, state,

regional, and national scales. To perform the analyses discussed in this report, the GWPC provided

the EPA with more than 39,000 FracFocus 1.0 disclosures in PDF format that were submitted by

operators before March 1, 2013. The EPA converted the data into a database (term ed the “project

database” in this report), which is a tool the public, researchers, and state resource managers may

use to facilitate analyses of the composition of hydraulic fracturing fluids. 8



### This study was conducted using disclosures with fracture dates between January 1, 2011, and

February 28, 2013. Although some disclosures in the project database have fracture dates before

January 1, 2011, that date was chosen as a starting point for the study time period because of the

agreement between GWPC and participating operators to disclose information for wells fractured

after the later of the two following dates : January 1, 2011, or the date the company agreed to

participate (GWPC and IOGCC, 2014). The EPA chose February 28, 2013, as the endpoint for the

6 Operators could upload information for wells hydraulically fractured after January 1, 2011. Disclosures in FracFocus are

assumed to include only chemical and water use information for hydraulic fracturing and not matrix treatments, which

avoid fracturing the production formation. Matrix treatments are designed to counteract decreasing permeability

resulting from formation damage near the wellbore by introducing acid, solvent, or chemicals into the formation

(Schlumberger, 2014).

7 More information on FracFocus 3.0 is available at http://www.fracfocus.org/major-improvements-fracfocusannounced.

8 The project database and the accompanying Data Management and Quality Assessment Report (US EPA, 2015) are

available at http://www2.epa.gov/hfstudy/published-scientific-papers. The Data Management and Quality Assessment

Report describes the structure of the database, data fields, and quality assessment of the data.Analysis of Data from FracFocus 1.0 March 2015

8 

### st udy period because it was the last full day that operators could have uploaded files prior to the

GWPC collecting the disclosures to send to the EPA.

During the timeframe of this study, six of the 20 states with data in the project database began

requiring operators to disclose chemicals used in hydraulic fracturing fluids to FracFocus

(Colorado, North Dakota, Oklahoma, Pennsylvania, Texas, and Utah). 9 

### Three other states started

requiring disclosure to either FracFocus or the state (Louisiana, Montana, and Ohio), and five states

required or began requiring disclosure to the state (Arkansas, Michigan, New Mexico, West Virginia,

and Wyoming). Alabama, Alaska, California, Kansas, Mississippi, and Virginia did not have reporting

requirements during the period of time studied in this report.

Extensive data quality reviews of the information in the project database were conducted. The data

were otherwise analyzed “as is” to ensure that the results represent the information disclosed by

operators as closely as possible. Because operators can update disclosures in FracFocus after the

original submission, the project database may not match the current data in FracFocus.



# 2. Methodology for Data Extraction and Analysis

This section describes the FracFocus source data and summarizes the methodologies used to

extract the data for inclusion in the project database and to analyze the data for presentation in this

report. It also describes the data management and quality assurance (QA) procedures used to

ensure that the project database and results from analyses conducted using the project database

represent data contained in the original PDF disclosures as accurately as possible.

Data extraction and QA methods used in this study are also described in the QA project plan (The

Cadmus Group, Inc., 2013). The accompanying Data Management and Quality Assessment Report (US

EPA, 2015 ) provides additional detail on methodology for extracting and analyzing data, including

specifics about database parameters.



## Database Development

2.1.1. Source Data

The source data provided by the GWPC were a bulk archive of 39,136 disclosures in PDF format

that were submitted by well operators to the FracFocus 1.0 website prior to March 1, 2013. Each

disclosure was initially submitted by the well operator to FracFocus in the form of a Microsoft Excel

spreadsheet and contained information on one production well that was hydraulically fractured

wi th a single fracture date. Each Excel spreadsheet was then converted into a PDF file by the

FracFocus website.

The PDF disclosures given to the EPA were created using FracFocus 1.0. Although FracFocus 2.0

became an option for submitting information in late 2012, it was not the exclusive disclosure

mechanism until June 2013. Because all disclosures in the project database have information on

production type and because disclosures created using FracFocus 2.0 do not contain this

9 Between February 5, 2011, and April 13, 2012, Pennsylvania required reporting to the state. As of April 14, 2012,

Pennsylvania required reporting to both the state and FracFocus.Analysis of Data from FracFocus 1.0 March 2015

9 

### information, all disclosures used to create the project database are assumed to have been generated

using FracFocus 1.0.

Each FracFocus 1.0 disclosure contains two tables of information, referred to as the “well header

table” and the “ingredients table” in this report. The well header table (outlined in blue in Figure 1)

contains information about the well itself, including : fracture date, location, operator name, well

name and number, American Petroleum Institute (API) well number, production type, true vertical

depth (TVD), and the total water volume used for hydraulic fracturing. The ingredients table

(outlined in red in Figure 1) provides information about the composition of the hydraulic fracturing

fluid. Trade names of additives, the purpose associated with each additive, and the identity and

maximum concentration of each ingredient in an additive and in the overall hydraulic fracturing

fluid are listed in the ingredients table.



### 2.1.2. Data Conversion and Extraction

To extract data from the disclosures, the original 39,136 PDF files were converted to Extensible

Markup Language (XML) 2003 spreadsheet (Microsoft Excel 2003 XML) files using Adobe Acrobat

Pro X (Adobe Systems Incorporated, 2011). The XML files were converted to comma-separated

values (CSV) files using a script developed in Python 2.7 (Python Software Foundation, 2012); the

script used the Beautiful Soup 4 library (Richardson, 2013) to read the XML files. The script parses

and sorts the XML data into CSV files. Parsing of the data resulted in two CSV files : one file with data

from the well header table and the other file with data from the ingredients table. The project

database (Microsoft Access 2013; Microsoft Corporation, 2012) into which the CSV files were

incorporated, therefore, has two primary tables : one for well header data and one for ingredient

Figure 1. Example FracFocus 1.0 disclosure.Analysis of Data from FracFocus 1.0 March 2015

10 

### data. The two

- table structure was chosen because an individual disclosure only has one set of well

header values

, but can have a variety of ingredients.

The well header and ing redients tables in the project database are linked by a constructed unique

identification field. The field was necessary

, because combinations of API well number and fracture

date were found to not be unique in the dataset and

, therefore

, could not serve a s unique

identifiers. Two hundred twenty

- eight disclosures were observed to have been updated at times

ranging from the same day as the original submission to as late as 588 days after the original

submission. In cases where there are duplicate disclosures with the same API well number and

fracture date, the most recent file (based on file modified date of the PDF ) was deemed the

authoritative disclosure. 10 

### Duplicate disclosures occur red , in part, because well operators

occasionally submitted an initial disc losure with preliminary data and later submitted a final

disclosure with revised or updated data for the same well/hydraulic fracturing event, but could not

then remove the initial disclosure. 11



### 2.1.3. Parsing Success

Parsing is defined as converting information from the PDF disclosures into data tables in the project

database. Success in parsing depends upon how effectively the software identifies symbols in

specific positions on the PDF files and categorizes them into the appropriate data fields in the

project d atabase

.

Data from more than 98% (38,530 of 39,136 ) of the original PDF disclosures were parsed and are

included in the project database. No data from 606 PDF files could be extracted during the parsing

process, and, therefore, none of the data from these disclosures are present in the project

database. 12 

### W ell header data were parsed from all of the 38,530 PDF files included in the project

database, and ingredient data were also parsed from 37,017 PDF files (9 6 % of disclosures in the

project database). Difficulties in extracting all data from an individual PDF disclosure arose because

the creation of the CSV files from XML files is highly sensitive to the original file formatting. Most

disclosures were prepared in a consistent format that enabled relati vely straightforward parsing of

data. However, some disclosures were uploaded to the FracFocus 1.0 website using templates that

had been modified by well operators, with columns or rows added or removed, or other formatting

changes. The modified templates could sometimes cause the parsing script to skip disclosures or

portions of disclosures. The effect of excluding data that failed to parse is that, based on percentage,

some states (e.g., Colorado, North Dakota, and Utah) with partially parsed or unparsed disclosures

are not as fully represented in the project database as they are in the PDF disclosures received from

the GWPC . The numbers of fully parsed, partially parsed, and unparsed data by state are presented

in Table 1.

10 The date of file modification was available to this project because it was associated with the PDF files given to the EPA

by the GWPC. The file modified date cannot be determined from the PDF disclosures available for public download on the

FracFocus website.

11 FracF ocus 2.0 allows operators to remove preliminary disclosures in such cases.

12 The 606 disclosures accounted for 1.5% of all the disclosures given to the EPA by the GWPC. Data from the 606

disclosures corresponded to a small amount of data compared to the en tire project database

. M anual entry of the data

was not performed.Analysis of Data from FracFocus 1.0 March 2015

11 

### Additional p arsing difficulties were identified during initial analyses of the project database that

resulted in unusual query results. Targeted comparisons of the project database to the original

PDFs files were performed to investigate the cause of unusual query results. 13 

### The targeted

13 If the results of an analysis indicated one or a few specific disclosures included problematic or unusual data, such as a

particularly high water volume in a dataset with low volumes, the data were confirmed with the original PDF file(s). For

unusual entries in a few tens of disclosures, approximately one PDF disclosure out of every 10 to 15 containing the

unusual data was compared to the project database. For problems more frequently enco untered (e.g., problematic data in

multiple fields or fields with multiple entries), two dozen disclosures from seven states were selected and the original

PDF files, the XML files, and the resulting database entries were compared. Comparisons to the origi nal PDF files were

also conducted for some database entries that were not believed to be outliers, but were otherwise noteworthy. For

example, in compiling data on non

- aqueous base fluid ingredients, the original PDFs for all disclosures that used

hydrocar bon

- based fracturing fluids without water were compared to the project database to verify that data from the

disclosures were accurately parsed into the project database. Table 1. Number of parsed, partially parsed, and unparsed disclosures , summarized by state

.

State Number of

disclosures Completely parsed Partially parsed

(well header only) Unparsed

Alabama 55 55 0 0

Alaska 37 37 0 0

Arkansas 1,462 1,461 1 0

California 754 727 16 11

Colorado 5,207 4,755 314 138

Kansas 139 134 3 2

Louisiana 1,058 1,035 8 15

Michigan 16 14 1 1

Mississippi 6 4 0 2

Montana 222 206 8 8

New Mexico 1,181 1,144 26 11

North Dakota 2,378 2,092 176 110

Ohio 156 147 1 8

Oklahoma 1,950 1,861 70 19

Pennsylvania 2,573 2,541 23 9

Texas 18,388 17,502 692 194

Utah 1,495 1,348 90 57

Virginia 90 90 0 0

West Virginia 295 280 4 11

Wyoming 1,503 1,426 67 10

State Uncertain* 171 158 13 0

Entire Dataset 39,136 37,017 1,513 606

* State location did not pass state locatio nal quality assurance criteria (Section 2.2.1).

Note: Analysis considered all disclosures (39,136).Analysis of Data from FracFocus 1.0 March 2015

12 

### comparisons found problematic entries in the project database, such as disclosures with invalid

entries in multiple fields, multiple entries in the trade name or purpose fields, infeasible data in the

concentration fields (i.e., letters instead of numbers), and unusually high or low water volumes.

Comparisons to the original PDF files indicated that problem atic entries in the database likely

resulted from atypical reporting styles , including modified data templates that interfered with

parsing, and possible data entry errors . The types and causes of problematic entries in the project

database were not quanti fied , and t he large number of ingredient records made individual

correction of these errors infeasible . Instead, problematic entries in the project database were

managed through the us e of QA filters that were designed to identify data elements that could not

be used for analyses (Sections 2.2 and 2.3)

. No changes were made to the project database as a

result of comparisons to the original PDF files, in keeping with the approach of presenting the data

as reported in the FracFocus 1.0 disclosures to the grea test degree possible. In summary, the large

number of disclosures in the project database and the use of QA filters in analyses ensured that the

results reflect the data in the PDF disclosures as accurately as possible.



## Data Standardization and Quality A ssurance

An assessment of data quality ensured that results of the analyses reflected the data contained in

disclosures

, while identifying obviously invalid or incorrect data to exclude from analyses. D ata that

were parsed and incorporated in the project d atabase must first pass two primary QA criteri a to be

included in analyses : the combination of fracture date and API well number for each disclosure

must be unique (i.e., no duplicates), and the fracture date must occur between January 1, 2011, and

Februar y 28, 2013. 14 

### While duplicate disclosures from the same fracturing event (i.e., same API well

number and same fracture date) were excluded from analyses, more than one disclosure for a given

well was included if the fracture dates on the disclosures differe d. As described in Section 2.1.1, 228

wells had more than one disclosure with the same fracture date , and the PDF file with the most

recently modified date was considered to be the authoritative version.

Table 2 lists the numbers of disclosures that were successfully parsed and the met primary QA

criteria. It shows that 38,050 disclosures (99% of the 38,530 disclosures in the project database)

met the two primary criteria and were candidates for analyses that rely on well header data (e.g.,

analyses of we ll locations and water volumes). The number of disclosures with parsed well header

and ingredients data that met the two primary criteria was 36,544 (95% of the disclosures in the

database). These disclosures were candidates for analyses of additive ingredients, water sources,

and proppants

To help identify invalid and extreme data and prepare for data analysis, the fields in the database

were subject to further QA review (beyond establishment of the two primary criteria of unique

status and date ran ge). Data values in the project database may be invalid, erroneous, extreme, or

missing either due to information entered into the original FracFocus 1.0 template or to the parsing

process that was used to create the project database. The QA process checks for internal

consistency among locational data, sets simple criteria for invalid data (e.g., incorrectly non

numeric entries in fields such as total water volume, fluid concentrations, and CASRNs ) , and

identifies extreme outliers. The QA process cannot, a nd was not intended to, determine the

14 Two hundred fifty

- one disclosures were excluded because the fracture date did not m eet the date criterion.Analysis of Data from FracFocus 1.0 March 2015

13 

### accuracy of the original data as entered by operators. Upon review, certain data fields were

subjected to simple standardizations by correcting for capitalization, hyphens, and slashes; spelling;

units; punctuation; an d synonymous entries.

The project database includes two presentations of the data extracted from the PDF disclosures to

enable straightforward review of all changes and streamlined tracing of disclosures back to the

source data. The first presentation is the data as originally parsed without any formatting

corrections

, or standardization s . The second version contains da ta after formatting, corrections,

and standardization were performed and also includes QA fields that indicate whether data in

certain fields meet QA criteria. The use of QA fields allows the data to remain unaltered (aside from

the standardizations and co rrections described below)

, but permits specific entries to be excluded

from an analysis (or properly accounted for) if they do not meet QA criteria. This approach results

in different numbers of disclosures being suitable for different types of analyses, and it serves to

maximize the number of disclosures that can be analyzed by not being more restrictive than

needed.



### 2.2.1. Quality Assurance of Locational Data

Well location al data in the well header table were subject to QA review to facilitate reliable

comparisons of hydraulic fracturing fluid composition among states and counties. Well locations

were validated by comparing the three ty pes of locational data reported by operators : latitude and

longitude, state and county, and stat e and county information encoded in the API well number.

Because the three locational sources were easily available and comparable, the location was

determined to have met QA criteria if all three types of locational data agreed. 15 

### The QA review was

perform ed separately for state and county information. If a disclosure did not meet locational

15 Well locations in Alaska were not subject to county

- level locational QA criteria

, because the five

- digit API well numbers

in Alaska are not organized by counties. The coordinates for all disclosures from Alaska fall within the bou ndaries of the

North Slope borough, which is shown on maps in this report. Table 2. Number and percentage of disclosures that had data successfully parsed from the well header and

ingredients tables and that met the primary QA criteria.

Well header

parsed Ingredient

table parsed Primary QA criteria

Number of

disclosures Percentage of

disclosures Unique

disclosures * Fracture d ate

within study

timeframe †

39,136 100.0%

Yes 38,530 98.5%

Yes Yes 38,301 97.9%

Yes Yes Yes 38,050 97.2%

Yes Yes 37,017 94.6%

Yes Yes Yes 36,793 94.0%

Yes Yes Yes Yes 36,544 93.4%

* Unique combination of fracture date and API well number (i.e., no duplicates)

.

† January 1, 2011 through February 28, 2013

.Analysis of Data from FracFocus 1.0 March 2015

14 

### criteria, it was either excluded from analyses that required locational information or was included

in a category that indicated the uncertainty in location. For exampl e, tables that provide data by

state include a row for “State U ncertain,” which includes disclosures with inconsistency among the

three types of state locational information. For maps showing data by county, data were excluded

from analyses if the disclosu res had inconsistent county locational information. A hatched pattern

in the map legend represents counties where all disclosures failed the county locational QA review

.

D isclosures for which state and county locational data did not meet the QA criteria we re excluded

from analyses that focused on specific counties (Sections 3.1.3 and 3.2.4)

.

Several steps were conducted to perform the locational QA. The state and county locations derived

from the API well number; the state and county assigned using latitud e and longitude; and the

operator reported state and county locations were compared to one another in Microsoft Excel,

resulting in six evaluations of locational accuracy. First, the leading five digits from the API well

number were converted to state and county names using lookup tables from the Society of

Petrophysicists and Well Log Analysts (2010). Second, the states and counties (US C ensus B ureau

, 2011) that intersect the coordinates reported in the latitude and longitude fields of the well header

were determined in a geographic information system (GIS) using ESRI ArcGIS 10.1 software ( ESRI

, 2012) after transforming all coordinates to the North American Datum 83 geographic coordinate

system. The states and counties that correspond to the transformed lat itude and longitude fields

were joined using the ArcGIS 10.1 Spatial Join geoprocessing tool, and the resulting attribute table

was exported to Microsoft Excel (Microsoft Corporation, 2002) . The comparisons ignored

variations in capitalization, spaces, and hyphens. The QA fields were used in the project database to

indicate whether the three locational data fields agreed, allowing the user to select only the data

with appropriate QA criteria for any given analysis.

Among the 38,050 disclosures meeting the two primary QA criteria, the state and county entries for

the three locational fields agreed in 36,306 disclosures (95% of 38,050). One hundred sixty

- two

disclosures (0.4 3 % of 38,050) failed to pass state locational QA criteria, and 1,744 disclosures

(4.6% of 38,050) did not pass county and state locational QA criteria . State locational data that met

QA criteria were available to pair with ingredients data for 36,395 disclosures (9 6 % of 38,050

disclosures). For 34,880 disclosures ( 92 % of 38,050 disclosures) , ingredients data were parsed and

both state and county locational data met QA criteria.



### 2.2.2. Addition of Geologic Information

To offer basic geologic context for the location of a disclosure, hydrocarbon basins (US EIA, 2007,

2011a, b; USGS, 1995) are shown o n sev eral figures in this report. 16 

### The hydrocarbon basin and

play names were added to the project database to allow analysis at a basin or play level. The

assignment of basin and play names to each disclosure is based solely on co

- location of the

disclosur e coordinates with the basin shapefile using ArcGIS 10.1, without further verification by

either the state or operator. Basins and plays were joined to each disclosure’s latitude and

longitude coordinates in the project database using the Spatial Join geop rocessing tool in ArcGIS

16 Figure s 2, 3 , 5, 6, and 7 display hydrocarbon basins in addition to data from the project database

. Appendix A includes a

map of shale basin s in the contiguous United States

.Analysis of Data from FracFocus 1.0 March 2015

15 

### 10.1. If a disclosure was located within the boundaries of two shale plays ( i.e ., in an area with

stacked plays), both names were indicated in the project database field (e.g., Marcellus/Utica)

.

The hydrocarbon basin and play datasets are used for general reference purposes with the

understanding that the boundaries are approximate and that production may not be occurring fro m

the co

- located play. 17 

### The shale basin boundaries are particularly useful because they capture the

gene ral extent of many major sedimentary basins in the contiguous United States and indicate

regions with active resource extraction. Geologic basins include all the individual formations within

the basin and provide a more confident, albeit general, geologic context to disclosures.



### 2.2.3. Quality Assurance of Ingredients

Ingredient names and CASRNs are entered by operators in the ingredients table. The names can

include a wide range of variations for a given ingredient, including synonyms, misspellings,

different pun ctuations and formatting, and different alpha

- numeric spacing. To identify ingredients

used in hydraulic fracturing fluids, entries of both names and CASRNs were verified and

standardized. 18 

### The CASRNs were determined valid for analyses after being verified with the

Chemical Abstracts Service (2014) ; i ngredient records with invalid CASRNs were excluded from

most analyses. 19 

### Note that this approach assumed that the CASRN entered into the database is

correct. The project database contains a total of 692 valid a nd unique CASRNs for ingredients

reported in disclosures that met the primary QA criteria.

Ingredient names for verified CASRNs were standardized using a list of unique chemical names

paired with CASRNs developed by the EPA. This standardization was needed because of the above

noted range of presentations of ingredient names. Table 3 shows examples of variations in

ingredient names as entered by operators and the standardized chemical name assigned by the

EPA ; this standardization facilitated analyses of in gredients. Because the ingredient names were

standardized, the names found in the report and the project database may differ from the names

reported by operators in the original PDF disclosures.

The EPA used standardized chemical names from Appendix A in the agency’s Study of the Potential

Impacts of Hydraulic Fracturing on Drinking Water Resources : Progress Report (2012) for the EPA

standardized chemical names used in the project database and in this report. 20 

### Chemical name and

structure quality control me thods were used to standardize chemical names for CASRNs found in

17 Sh ale plays assigned to the disclosures in the project database using GIS shapefiles were compared to corresponding

information from the commercial database DrillingInfo (2011) to evaluate the accuracy of the GIS method. DrillingInfo

records were matched wit h 7,153 disclosures in the project database using the API well number. Assignment of shale

play s to disclosures in the project database using GIS agreed with the play reported to DrillingInfo in 83% (5,929 of 7

, 153

disclosures) of the disclosure locations (US EPA, 2015 ).

18 A CASRN and chemical name combination identify a chemical substance, which can be a single chemical (e.g.,

hydrochloric acid) or a mixture of chemicals (e.g., hydrotreated light petroleum disti llates).

19 Analyses of additive ingredients, proppants, and non

- aqueous base fluid constituents required valid CASRNs. The valid

CASRN QA criteria was not used for the analysis of water sources, because operators entered “water” or another term in

the trad e name field and did not always enter a chemical name or CASRN.

20 Table A

- 1 in the Progress Report

.Analysis of Data from FracFocus 1.0 March 2015

16 

### the project database but not included in Appendix A of the Progress Report

. 21 

### The same methods

were used in the development of Appendix A of the Progress Report and ensure correct chemical

na mes and CASRNs.

In applying the EPA

- standardized chemical list to the ingredient records in the project database,

standardized chemical names were assigned to 787,522 ingredient records (65% of 1,218,003

records) from the 36,544 unique, fully parsed disclosures that met the date criterion. Because the

CASRNs for the remaining 35% (430,481 records) of ingredient records were invalid, they could

not be assigned a standardized chemical name and were excluded from anal yses of additive

ingredients

.

Fields were established in the project database to indicate whether each ingredient record met QA

criteria for the CASRN, additive concentration, and fracturing fluid concentration fields. Individual

21 In the majority of cases, valid CASRNs and the associated ingredient names in the project database were paired

correctly for a given CASRN. If an ingredi ent name (whether specific or non

- specific) did not match the CASRN reported

by the operator, the CASRN was added to a chemical name standardization list and assigned a correct chemical name. The

chemical standardization list consists of CASRNs paired with appropriate chemical names and was used to standardize

chemical names in the project database based on the CASRNs reported by operators. This process was undertaken

because numerous synonyms and misspellings for a given chemical were present in the origin al data. Standardized,

specific chemical names were identified using the EPA’s Distributed Structure

- Searchable Database Network (US EPA,

2013), the EPA’s Substance Registry Services database (US EPA, 2014a), and the U.S. National Library of Medicine ChemI D

database (US NLM, 2014). Additional information on chemical name and structure quality control methods can be found

at http://www.epa.gov/ncct/dsstox/ChemicalInfQAProcedures.html. Table 3. Examples of ingredient name standardization

.

Operator

- Reported

CASRN Examples of Operator

- Reported

I ngredient N ames EPA

- S tandardized Chemical N ame

7647

- 01

- 0 Hydrogen chloride Hydrochloric acid

Hydrochloric acid

HCl

Hydrogen Chloride Solution

Hydroogen Chloride

7647

- 14

- 5 Sodium chloride Sodium chloride

Sodium chloide

Sodium chlorite

64742

- 47

- 8 Distillates Distillates, petroleum, hydrotreated light

Distillates (petroleum)

Distillates petro

Distillates petroleum, hydrotreated

77

- 92

- 9 Citric Acid Anhydrous Citric acid

Citric Acid Solution

Citric Acid

107

- 21

- 1 Ethylene Glycol Ethylene glycol

Ethyene Glycol

Ethylene Dlyco

Ehtylene Glycol

14808

- 60

- 7 Quartz Quartz

Crystalline silica

Silicon dioxide

Crystalline silica quartzAnalysis of Data from FracFocus 1.0 March 2015

17 

### concentrations (reported a s maximum concentrations) of ingredients in additives and in hydraulic

fracturing fluid were considered valid and included in appropriate analyse s if they had a value

between 0 % and 100%. In this way, non

- numeric entries and implausibly high numeric values (e.g.,

typographical errors from operators, invalid entries due to parsing difficulties) were excluded from

summary statistics. Ingredient records that did not meet the 0 % to 100% criterion for the additive

and fracturing fluid concentration fields were e xcluded from analyses for which median and

percentile calculations were performed. A total of 295 disclosures (0.81% of 36,544 disclosures)

had no valid entries in either the additive or fracturing fluid concentration field for any of their

ingredient reco rds. Invalid entries for both concentration fields were found for 271,312 individual

ingredient records (22% of 1,218,003 ingredient records). 22 

### (Some disclosures had a mix of

ingredients with valid and invalid concentrations. Thus, the 271,312 ingredients were spread out

over more than the 295 disclosures.)

Lack of a valid CASRN and ingredient concentration data in the proper field may have been due to

several factors. Operators sometimes did not list CASRN entries for ingredients. 23 

### Fields for

concentration data were sometimes left blank. Also, operators may have made data entry errors or

information from the original PDFs may have been assigned to the wrong fields due to the parsing

difficulties related to modified formats.

Confidential Business Information

. Operators can specify ingredients as confident ial business

information (CBI; also referred to as trade secret or proprietary) when submitting disclosures to

FracFocus . As a result, the identit y of a specific chemical may not be known for the analyses

con ducted in this report

. Operators indicated CBI ingredients using 239 terms in the CASRN and

chemical name fields that clearly indicate that the ingredients are considered a trade secret.

Omission of the chemical name or CASRN from a CBI record disqualifie d that record for additive

ingredient analyses. The CBI ingredient record s in the project database were reviewed to assess the

frequency at which operators claimed CBI status and the extent to which disclosures available for

summary analyses would be reduce d by the exclusion of CBI ingredient records. More than 70% of

disclosures contained at least one ingredient identified as CBI, as shown in Table 4. Of the 25,796

disclosures that contain ed CBI ingredients (excluding duplicates and those that did not meet the

date criterion), the average number of CBI ingredients per disclosure was five. The total number of

ingredient records claimed as CBI or a related term was 129,311, or 11% of all ingredient records

that were completely parsed from disclosures that met the primary QA criteria . Arthur et al. (2014)

reported a similar proportion of CBI records in their study of FracFocus data (13% of ingredients;

approximately 200,000 records). Although these ingredients are reported as proprietary,

information on the gene ral chemical class is frequently provided; related information is

summarized in Appendix B.

Atypical Formatting. Atypical formatting of ingredient and trade name information on disclosures

also caused information to fail QA criteria and be excluded from analyses. Data were entered in

some disclosures so that trade names and purposes were decoupled from ingredient names,

22 Disclosures containing these ingredient records meet the primary QA cr iteria

.

23 The FracFocus 2.0 submission system prohibits operators or their re gistered agents from entering an ingredient

without a CASRN and issues a warning if the CASRN is not properly formatted or has the incorrect number of digits.Analysis of Data from FracFocus 1.0 March 2015

18 

### CASRNs, and maximum concentrations. Such reporting styles allow the operator to disclose

chemicals while protecting proprietary information. The decoupling of related information

occurred in one of three ways:

 An operator entered all trade names into a single cell in the tem plate and all purposes into

another cell

.

 An operator entered trade names and purposes in a set of rows without ingredient

information and entered ingredient names, CASRNs, and maximum concentrations in a

series of rows below all of the trade names and pu rposes. This strategy is proposed by the Table 4. Additive ingredients reported as confidential business information (CBI), summarized by state.

State Number of disclosures with

parsed ingredient s table Percent of disclosures with at least

one reported CBI ingredient

Alabama 55 0%

Alaska 37 100%

Arkansas 1,449 78%

California 704 80%

Colorado 4,624 57%

Kansas 133 60%

Louisiana 1,030 60%

Michigan 14 79%

Mississippi 4 100%

Montana 205 68%

New Mexico 1,136 89%

North Dakota 2,078 64%

Ohio 147 86%

Oklahoma 1,839 68%

Pennsylvania 2,463 48%

Texas 17,384 76%

Utah 1,339 91%

Virginia 90 24%

West Virginia 273 40%

Wyoming 1,391 75%

State Uncertain* 149 82%

Entire Dataset 36,544 71%

* State location did not pass state locational quality assurance criteria.

Note: Analysis considered 36,544 disclosures that met selected quality assurance criteria , including:

completely parsed; unique combination of fracture date and API well n umber; and fracture date between

January 1, 2011, and February 28, 2013. Disclosures that did not meet quality assurance criteria (1,986) or

other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

19 

### Secretary of Energy Advisory Board (SEAB) as appropriate for operators to fully disclose

chemicals and remain protective of business interests (SEAB, 2014)

.

 An operator entered some ingredients in a section separate from other ingredients, which

resulted in ingredients being included in unintended, incorrect fields when parsed. An

example would be non

- hazardous ingredients not found on Material Safety Data Sheets

(MSDS) that operators disclosed to FracFocus. The non

- MSDS ingredients were entered in

a separate section than ingredients found on an MSDS. The disclosures typically included a

red cell with explanatory text separating the two areas of the ingredients table. The text in

the red separator itself could be inco rporated into the ingredient name or CASRN fields

incorrectly when parsed.

These entry options rendered it difficult to match ingredients with purposes and trade names and

may have resulted in invalid entries in the trade name, supplier, ingredient name, o r CASRN fields.

Ingredient records that met the critical QA criteria (valid CASRN, valid maximum concentrations)

were incorporated into basic analyses of ingredient occurrence even if their associated trade name

and purpose fields had problematic entries ( because those two fields are not relevant to all

analyses.) Quantifying the number of ingredient records and disclosures affected by the data entry

formats would require a comprehensive comparison of the original PDFs to the project database,

which was inf

easible given the large numbers of ingredient records and disclosures

.



## Analyses

Analyses were conducted to study disclosure locations and ingredients used in hydraulic fracturing

fluids on regional, state, and national scales. Summary information was also compiled to allow a

comparison among five counties with extensive hydraulic fracturing activities , as indicated by the

number of disclosures in the project database

.

Analyses of the project database were designed to ensure that the results presented in th is report

represent the data contained in the original PDF disclosures , while identifying obviously invalid or

incorrect data to exclude from analyses

. For these reasons, results of the analyses represent only

the data found in the project database

, and an extrapolation of the results to the entirety of

hydraulically fractured oil and gas production wells in the United States was not conducted.



### 2.3.1. Specific Criteria for Analyses

For each analysis, information was extracted from the project database by designing a query that

included specific QA criteria to address limitations in the project database. As noted in Section 2.2,

the following primary QA criteria were applied to all analyses : a unique combination of fracture

date and API well number and a fracture date between January 1, 2011, and February 28, 2013

(Table 1; 38,050 disclosures met these two criteria). The search criteria described below were used

in queries to help target specific types of information (e.g., use of search terms or selectio n of

certain types of purposes or ingredients). Table 5 identifies search filters and QA criteria used for

figures and tables presented in this report , along with the resulting numbers of disclosures and

ingredient records included in each analysis

.

Specif ic Criteria and Approaches for Additive Ingredient Analys e s . Analyses of the occurrence or

concentrations of additive ingredients included ingredient records from trade names with purposesAnalysis of Data from FracFocus 1.0 March 2015

20 

### other than those associated with base fluids or proppants. Ingredie nt records for these analyses

were required to have valid maximum concentrations (between 0% and 100%) and valid CASRNs

(Section 2.2.3). The above QA criteria were met by 676,376 ingredient records (row for Table 7 in

Table 5).

Specific Criteria and Approa ches for Base Fluid Analys e s. Disclosures were included in analyses of

total water volumes if the entry in the total water volume field in the well header table (Figure 1)

was less than or equal to 50 million gallons. 24 

### Two hundred fifty

- five disclosures di d not meet the

volume criterion and were excluded from relevant analyses: 11 disclosures exceeded 50 million

gallons; water volume was not reported for 165 disclosures; and for 79 disclosures, the water

volume was ambiguous as parsed.

Water as a base fluid was identified by querying the trade name and comments fields for a suite of

terms and with the criterion of a maximum hydraulic fracturing fluid concentration greater than or

equal to 1% by mass. The threshold of 1% distinguished water as a base fluid fr om water listed as

an additive ingredient. The cutoff of 1% was chosen after considering the median and 95th

percentile maximum fluid concentrations of frequently reported additive ingredients as well as the

median maximum fluid concentration of all additi ve ingredients per disclosure. 25 

### Because operators

often left the purpose field blank when listing water as a base fluid, the purpose field was not used

for this analysis. The analyses of base fluids included 36,046 unique disclosures with fracture dates

in the study time period and used ingredient records with maximum fluid concentrations greater

than 1% by mass (Table 5; rows for Tables 17 and 18).

To compile information on water sources, the project database was queried for the use of source

water descriptors in the trade name and comments fields. Although not explicitly required by

FracFocus, some operators included terminology in their submissions that indicated the source of

water used for the base fluid (e.g., “fresh,” “surface water”). Operator s most commonly listed source

water information as a trade name or in the comments field and usually included estimates of the

maximum concentration of water type in the hydraulic fracturing fluid.

To identify base fluid ingredients that were used either t o enhance water

- based fluid systems or as

an alternative to water

- based systems, the project database was queried for non

- aqueous

ingredients with base fluid

- related terms in the purpose field. Preliminary queries indicated that

non

- aqueous constituents su ch as gases and hydrocarbons were identified by purpose (whereas

water used as a base fluid is often not listed with a purpose). Furthermore, some constituents were

identified with more than one purpose even when above the 1% threshold (e.g., petroleum

24 The criterion of 5 0 million gallons or less for the reported total water volume was chosen based on the identification of

extreme values in the distribution of the data and after speaking with Mike Nickolaus of the GWPC regarding the extreme

values compared to ranges of kno wn water use. Eleven disclosures indicated water volumes in excess of 50 million

gallons per disclosure , with the largest total water volume reported as greater than 100 million gallons . Typical per well

water volumes reported by Clark et al. (2013), Jiang et al. (2014), and Nicot and Scanlon (2012), are well below the 50

million gallon per disclosure threshold.

25 Well operators reported the maxi mum concentration of an ingredient in the additive and in the hydraulic fracturing

fluid. Therefore, the median a nd 5th and 95th percentile concentration values presented in this report represent those

value s of the reported maximum concentration s.Analysis of Data from FracFocus 1.0 March 2015

21 Table 5. F ilters , QA criteria , disclosures, and ingredient records associated with analyses presented in this report

. “N/A” indicates not applicable.

Figure or Table WELL HEADER CRITERIA INGREDIENT TABLE CRITERIA TOTAL COUNT S Well header parsed

Unique disclosure Fracture date within study timeframe Valid water volume Location filter state Location filter county Production type Ingredient table parsed Valid CASRN

Valid a dditive & f luid

c oncentrations Purpose: Proppant Purpose: Base fluid Valid purpose Ingredient type Disclosures Ingredients

Figure 2. Geographic distribution of disclosures in

the project database Yes Yes Yes Yes 37,888 N/A

Figure 3. Geographic distribution of disclosures by

production type Yes Yes Yes Yes 37,888 N/A

Figure 4. Distribution of fracture dates in the

project database Yes Yes Yes Yes 37,888 N/A

Figure 5. Cumulative total water use, summarized

by county Yes Yes Yes Yes 37,888 N/A

Figure 6. Median total water volumes per

disclosure, summarized by county Yes Yes Yes Yes 37,888 N/A

Figure 7. Variability in reported total water volumes

per disclosure, as measured by the difference

between the 5th and 95th percentiles Yes Yes Yes Yes 37,888 N/A

Table 4. Additive ingredients reported as

confidential business information (CBI),

summarized by state Yes Yes Yes Yes CBI 36,544 N/A

Table 6. Number and percentage of unique

disclosures in the project database with a fracture

date between January 1, 2011, and February 28,

2013 Yes Yes Yes 38,050 N/A

Table 7. Number of unique additive ingredients per

disclosure, summarized by state Yes Yes Yes Yes Yes Yes Additives 34,675 676,376

Table 8. Twenty most frequently reported additive

ingredients in oil disclosures, ranked by frequency

of occurrence Yes Yes Yes Yes Yes Yes Yes Additives 17,640 385,013

Table continued on next pageAnalysis of Data from FracFocus 1.0 March 2015

22 Figure or Table WELL HEADER CRITERIA INGREDIENT TABLE CRITERIA TOTAL COUNT S Well header parsed

Unique disclosure Fracture date within study timeframe Valid water volume Location filter state Location filter county Production type Ingredient table parsed Valid CASRN

Valid a dditive & f luid

c oncentrations Purpose: Proppant Purpose: Base fluid Valid purpose Ingredient type Disclosures Ingredients

Table 9

. Twenty most frequently reported additive

ingredients in gas disclosures, ranked by frequency

of occurrence Yes Yes Yes Yes Yes Yes Yes Additives 17,035 291,363

Table 10. Frequently reported additive ingredients

and commonly listed purposes for additives that

contain the ingredients Yes Yes Yes Yes Yes Yes Additives 34,675 676,376

Table 11. Counties selected to illustrate diversity in

additive ingredients at small scales Yes Yes Yes Yes Yes 4,066 N/A

Table 12. Comparison of 20 most frequently

reported additive ingredients among selected

counties Yes Yes Yes Yes Yes Yes Yes Yes Additives 3,622 61,502

Table 13. Non

- aqueous ingredients reported in base

fluids Yes Yes Yes Yes Yes Yes Yes Base Fluids 34,675 676,376

Table 14. Use of non

- aqueous ingredients in base

fluids, summarized by state Yes Yes Yes Yes Yes Yes Yes Base Fluids 34,675 676,376

Table 15. Total w ater volumes, summarized by state Yes Yes Yes Yes 37,796 N/A

Table 16. Total w ater volumes for selected counties

in approximately the 90th percentile of

disclosures Yes Yes Yes Yes 37,796 N/A

Table 17. Number of disclosures having terms

suggestive of water sources, summarized

by state Yes Yes Yes Yes Yes Base Fluids 36,046 925,972 *

Table 18. Median maximum fluid concentrations of

water by source, summarized by state Yes Yes Yes Yes Yes Base Fluids 36,046 925,972 *

Table continued on next pageAnalysis of Data from FracFocus 1.0 March 2015

23 Figure or Table WELL HEADER CRITERIA INGREDIENT TABLE CRITERIA TOTAL COUNT S Well header parsed

Unique disclosure Fracture date within study timeframe Valid water volume Location filter state Location filter county Production type Ingredient table parsed Valid CASRN

Valid a dditive & f luid

c oncentrations Purpose: Proppant Purpose: Base fluid Valid purpose Ingredient type Disclosures Ingredients

Table 19. Ten most frequently reported proppant

ingredients, ranked by frequency

of occurrence Yes Yes Yes Yes Yes Yes Yes Proppants 34,675 676,376

Table B

- 1. Chemical families for CBI ingredient

records Yes Yes Yes Yes CBI 36,544 N/A

Table B

- 2. Most frequently reported chemical

families among CBI ingredients and their most

commonly listed purposes Yes Yes Yes Yes CBI 36,544 N/A

Appendix C

. Histograms of h ydraulic f racturing f luid

c oncentrations for most frequently reported

additive i ngredients Yes Yes Yes Yes Yes Yes Yes Additives 34,675 676,376

Table D

- 1. Disclosures per state, summarized by

well operator Yes Yes Yes 38,050 N/A

Table E

- 1. Reporting regulations for states with data

in the project database Yes Yes Yes Yes 37,888 N/A

Table F

- 1. Number of disclosures, summarized by

additive purpose categorie s Yes Yes Yes Yes Additives /

CBI 36,544 1,218,003

Table G

- 1. Twenty most frequently reported

additive ingredients in Andrews County, Texas,

ranked by frequency of occurrence Yes Yes Yes Yes Yes Yes Yes Yes Additives 1,088 20,716

Table G

- 2. Twenty most frequently reported

additive ingredients in Bradford County,

Pennsylvania, ranked by frequency of occurrence Yes Yes Yes Yes Yes Yes Yes Yes Additives 510 6,002

Table G

- 3. Twenty

- one most frequently reported

additive ingredients in Dunn County, North Dakota,

ranked by frequency of occurrence Yes Yes Yes Yes Yes Yes Yes Yes Additives 311 6,450

Table continued on next pageAnalysis of Data from FracFocus 1.0 March 2015

24 Figure or Table WELL HEADER CRITERIA INGREDIENT TABLE CRITERIA TOTAL COUNT S Well header parsed

Unique disclosure Fracture date within study timeframe Valid water volume Location filter state Location filter county Production type Ingredient table parsed Valid CASRN

Valid a dditive & f luid

c oncentrations Purpose: Proppant Purpose: Base fluid Valid purpose Ingredient type Disclosures Ingredients

Table G

- 4. Twenty most frequently reported

additive ingredients in Garfield County, Colorado,

ranked by frequency of occurrence Yes Yes Yes Yes Yes Yes Yes Yes Additives 1,166 17,337

Table G

- 5. Twenty most frequently reported

additive ingredients in Kern County, California,

ranked by frequency of occurrence Yes Yes Yes Yes Yes Yes Yes Yes Additives 547 10,997

Table H

- 1. Total w ater volumes, summarized by

county Yes Yes Yes Yes 37,796 N/A

* Valid maximum concentration in additive criteria not used for this analysis.Analysis of Data from FracFocus 1.0 March 2015

25 

### distillates are listed as a gelling agent as well as a carrier ingredient). It was, therefore, considered

reasonable to use the purpose field for this analysis. Purpose terms that were used to identify these

ingredients included variations on: base fluid, fracturing fluid, gas, carrier, foamer or foaming agent,

energizer or energizing agent, carbon dioxide, and nitrogen. As with water base fluids, a maximum

fluid concentration of 1% was chosen as the minimum limit to identify non

- aqueous ingredients as

base fluids. The analyses of non

- aqueous base fluids included 34,675 unique disclosures and used

ingredient records with maximum fluid concentrations greater than 1% by mass, and valid CASRN

and concentrations (Table 5; rows for Tables 13 and 14).

Description of Figure and Table Footnotes. Footnotes were developed to provide transparency about

how data were used for each analysis , because t he number of disclosures and ingredient records for

individual analyses varied depending on the QA criteria used. The use of QA criteria in the analyses

is describe d in footnotes associated with each figure and table throughout Section 3. The

descriptions and numbers in the footnotes do not reflect other analysis

- specific choices that were

made, such as screening for certain purposes or specific concentrations (e.g. purpose of base fluid,

concentration ≥1% by mass). Such decisions are described in the text in this section and in other

appropriate sections.



### 2.3.2. Calculations

The approach to calculation s of summary statistics was chosen to support an understandable

synopsis of the analysis results

, while minimizing the effects of limitations associated with the

project database . In addition to the parsing problems discussed above, invalid values in the

da tabase also exist due to blank fields in disclosures, possible data entry errors, or non

- reporting of

CBI. These issues are particularly problematic for data in the ingredients table . In many cases,

invalid entries were easily excluded during analysis by u se of the previously described QA fields

(e.g., when alphabetic characters occur in numeric fields, such as concentration or CASRN fields). In

other cases, however, anomalous numbers that still meet QA criteria are seen in the concentration

fields (e.g., a maximum fluid concentration of 100% by mass in a field for an ingredient observed to

be used in small quantities in other disclosures).

Anomalous data that meet QA criteria, while small in number, tend to disproportionately affect

summary statistics by a rtificially inflating or decreasing the maximum, minimum, or mean. As an

example, sodium hydroxide was frequently reported in disclosures (38% of 34,675 disclosures that

met the primary QA requirements ). The median maximum concentration of sodium hydroxide in

hydraulic fracturing fluid is 0.0092% by mass, but the mean maximum fluid concentration is

several order s of magnitude greater (0. 10 %). The mean is influenced by a maximum concentration

(100%) that is orders of magnitude greater than the 95th percentil e (0.077%). The maximum

concentrations

, at times

, represent extreme values that may be included in the project database due

to parsing problems or errors in operator data entry.

To minimize the effects of anomalously high and low concentration values on th e summary

statistics, the median was used to represent the central tendency of the dataset, and the 5th and

95th percentiles were used to represent the range. Data at the extreme ends of ranges (below the

5th and above the 95th percentiles) remain in the p roject database. Calculations such as average or

variance were not performed on the data. The median and the 5th and 95th percentiles wereAnalysis of Data from FracFocus 1.0 March 2015

26 

### calculated using the default method in the statistical program R (R Core Team, 2013). Tables and

figures state the nu mber of disclosures (i.e., frequency of reporting ) to give additional context to the

data.

To assess the accuracy of the median as a measure of central tendency and to examine the

distributions of maximum additive ingredient concentrations in hydraulic fra cturing fluid s

, histograms were prepared for the twenty most frequently reported additive ingredients (Appendix

C). The histogram shapes vary, with some appearing log

- normal and others with a more irregular

pattern or a roughly bimodal distribution. 26 

### The v ariety in distributions indicates that, for some

additive ingredients , the median is a more reliable indicator of ce ntral tendency than for others.

Irregular or bimodal distributions may result from use of a n additive ingredient in more than one

additive t ype (necessitating different amounts) or from variable additive needs depending upon

factors such as subsurface geochemistry or different operational practices.

If an additive ingredient was listed in more than one additive in a disclosure, the individual

maximum fluid concentrations were summed to estimate the total maximum fluid concentration for

that additive ingredient in the disclosure. 27 

### The median and percentile maximum concentrations in

hydraulic fracturing fluid s were calculated from these summed va lues. Because the concentrations

of each additive ingredient are the maximum possible concentrations, the resulting statistics on

hydraulic fracturing fluid concentrations can be considered upper limits. Also, because maximum

concentrations were reported ( and in some cases operators appea red to have entered additive

concentrations or other values in the fracturing fluid concentration field)

, the cumulative maximum

fluid concentrations of an ingredient across all additives in a disclosure sum to greater than 100%

by mass in some disclosures.

Frequency of reporting for ingredients at the disclosure level was calculated by summing the

number of disclosures that reported a specific ingredient . Frequency of reporting at the ingredient

record level was calculated by summing the number of individual ingredient records for a specific

ingredient

. Percentages presented in the tables were calculated based upon the total number of

disclosures or ingredient records that met the QA criteria for a given analysis and other, query

specific criteria.

For analyses of total water volumes , cumulative volume s were calculated by adding the total water

volume reported in the well header table for all disclosures in a chosen unit area. Total w ater

volumes were also summarized on a per

- disclosure basis by calculating the median and 5th and

95th percentiles among all disclosures for an area of interest ( i.e ., state, county, entire dataset).

Median per

- disclosure water volumes for a given area reflect the central tendency of the dataset,

and 5th and 95th percentiles provide information on the range of the dataset.

26 The most frequently reported additive ingredients with non

- normal distributions include : 2

- butoxyethanol,

hydrotreated light petroleum distillates, ethanol, naphthalene, potassium hydroxide, quartz, and heavy aromatic

petroleum solvent naphtha.

27 Fluid concentrations for individual ingredient records must meet the initial QA criteria of maximum fluid concentration

by mass between 0 % and 100% prior to inclusion in the analysis.Analysis of Data from FracFocus 1.0 March 2015

27 

# 3. Results

The project database includes data extracted from 38,530 disclosures in 20 states that were

uploaded to FracFocus before March 1, 2013. 28 

### Operators identified 19,908 disclosures as oilproducing wells and 18,622 as gas-producing wells. 29 

### Analyses included well locational data, total

water volumes, and production type for 38,050 disclosures that met primary QA criteria (19,769 oil

wells and 18,281 gas wells)

. Ingredient data were considered for 36,544 disclosures that met

primary QA criteria (Table 1).

Operators provided locational information for the wells represented in the disclosures. This

information enabled comparisons among hydraulic fracturing fluid composition in different regions

of the country on a state or county basis. Figure 2 shows the geographic distribution of well

28 Nine hydraulic fracturing service companies reported that they hydraulically fractured nearly 25,000 wells in 30 states

between approximately September 2009 and September 2010 (US EPA, 2012). Assuming that hydraulic fracturing

continued to occur in the 30 states through March 2013, this suggests that disclosures uploaded to FracFocus and

analyzed for this study may not encompass all hydraulic fracturing activity that occurred between 2011 and 2013.

29 Appendix D identifies the operators that submitted disclosures and the states where the ir wells are located. Note: Shale basins are those sedimentary basins associated with oil and gas shale plays (US EIA, 2011a). The shale basins offer

basic geologic context for the location of a disclosure; disclosures likely represent more oil and gas producing formations than

only shale formations. Analysis considered 37,888 disclosures that met selected quality assurance criteria , including: unique

combination of fracture date and API well n um ber; fracture date between January 1, 2011, and February 28, 2013; and with

confirmed state location. Disclosures that did not meet quality assurance criteria were excluded from analysis (642).

Figure 2. Geographic distribution of disclosures in the projec t database.Analysis of Data from FracFocus 1.0 March 2015

28 

### locations as reported in the project database . Generally, the locations of well s represented in the

disclosures are clustered in the northeast (mainly in and around Pennsylvania), the west central

portion of the co untry (from North Dakota and Wyoming through Texas and Louisiana), and in

California.

Many counties are represented in the project database , but a large number of counties have few

disclosures in the database. The project database indicates well locations in 406 counties

, with a

range of 1 to 3,016 disclosures per county. Approximately 50% of counties represented in the

project database have less than 13 disclosures, and 26% of the counties have only one or two

disclosures.

Counties with particularly larg e numbers of disclosures are in California, Colorado, North Dakota,

Pennsylvania, and Texas. This distribution is generally consistent with areas of the country that

have experienced the greatest growth in oil and gas production since the late 2000’s

— namely, the

Bakken (North Dakota and Montana), the Eagle Ford (Texas), the Haynesville (Texas, Louisiana, and

Arkansas), the Marcellus (Pennsylvania, West Virginia, Ohio, New York

, and Maryland), the

Niobrara (Colorado, Wyoming, Nebraska, and Kansas )

, the Permian Basin (Texas and New Mexico),

and the Utica (Ohio) . These basins and formations accounted for nearly 95% of growth in domestic

oil production and virtually all of the growth in domestic natural gas production during 2011 and

2012 (US EIA, 20 14 ).

The geographic distribution of disclosures should be considered when interpreting results of

analyses presented in this report

, because certain parts of the country are more heavily

represented than others, as shown in Table 6. For example, 48% of al l disclosures in the project

database are located in Texas. Arthur et al. (2014) also noted that almost half the disclosures in

FracFocus are from Texas. Therefore, the disclosure data associated with Texas influence summary

analyses of the entire project database toward hydraulic fracturing practices in Texas.

Because operators provided information on production type in FracFocus 1.0, it is possible to use

production type to add additional context to the data in the pro ject database. Figure 3 identifies t he

production type by county as a proportion of disclosures. Although production in many counties

was predominantly (>80%) oil or gas, some counties had a mix of oil

- and gas

- reporting

disclosures. Disclosures in Ohio, Pennsylvania, and West Virginia indic ated predominantly gas

production (>80%), whereas disclosures in North Dakota, West Texas, and northern Wyoming

showed predominantly oil production. Disclosures from many states indicated the presence of both

oil and gas production wells.

Influence of S tat

e Reporting Requirements. By February 2013, six of the 20 states with data in the

project database had implemented regulations that required well operators to disclose chemicals

used in hydraulic fracturing fluids to FracFocus : Colorado, North Dakota, Okla homa, Pennsylvania,

Texas, and Utah. 30 

### Three additional states (Louisiana, Montana, and Ohio) required disclosure to

30 Between February 5, 2011, and April 13, 2012, Pennsylvania required reporting to the state. As of April 14, 2012,

Pennsylvania required reporting to both the state and FracFocus.Analysis of Data from FracFocus 1.0 March 2015

29 

### either FracFocus or the state, and five s tates (Arkansas, Michigan, New M exico, West Virginia, and

Wyoming) required reporting to the state

. 31 

### R eporting requirements for the six states with

mandatory reporting to FracFocus became effective during the time period studied in this report.

T he changing nature of reporting requirements may have influenced both the number and

geographic distribution of disclosures in the project database.

Figure 4 shows the distribution of fracture dates in the project database and indicates whether the

disclosure was mandatory or voluntary. Mandatory disclosures are defined, in this report, as

31 Appendix E describe s reporting requirements for the 20 states discussed in this study. Table 6. Number and percentage of unique disclosures in the project database with a fracture date between

January 1, 2011, and February 28, 2013.

State Number of disclosures Percentage of disclosures

Texas 18,075 48%

Colorado 4,938 13%

Pennsylvania 2,483 6.5%

North Dakota 2,254 5.9%

Oklahoma 1,909 5.0%

Wyoming 1,457 3.8%

Arkansas 1,450 3.8%

Utah 1,429 3.8%

New Mexico 1,162 3.1 %

Louisiana 1,038 2.7%

California 718 1.9%

West Virginia 277 0.73%

Montana 213 0.56%

Ohio 148 0.39%

Kansas 136 0.36%

Virginia 90 0.24%

Alabama 55 0.14%

Alaska 37 0.097%

Michigan 15 0.039%

Mississippi 4 0.011%

State Uncertain * 162 0.43%

Entire Dataset 38,050 100%

* State location did not pass state locational quality assurance criteria.

Note: 480 d isclosures that did not meet primary quality assurance criteria wer e excluded from analysis.Analysis of Data from FracFocus 1.0 March 2015

30 

### disclosures that occurred in one of the six states with mandatory reporting to FracFocus and had a

fracture date after the state’s regula tory effective date. 32 

### Voluntary disclosures included disclosures

that fell into one of the following categories: disclosures from states with no reporting

requirements, states with reporting requirements that did not mandate reporting to FracFocus (i.e.,

states requiring disclosure to the state and states requiring disclosure to either the state or

FracFocus) , or disclosures that had a fracture date prior to a state’s regulatory effective date for

mandatory reporting to FracFocus. Data presented in Figure 4 suggest that, overall, the number of

disclosures in the project database increased when mandatory reporting requirements to

FracFocus were in place. 33 

### The observed increase in the number of disclosures in the project Note: Shale basins are those sedimentary basins associated with oil and gas shale plays (US EIA, 2011a). The shale basins off er

basic geologic context for the location of a disclosure; dis closures likely represent more oil and gas producing formations than

only shale formations. Analysis considered 37,888 disclosures that met selected quality assurance criteria , including: unique

combination of fracture date and API well n umber; fracture da te between January 1, 2011, and February 28, 2013; and with

confirmed state location. Disclosures that did not meet quality assurance criteria were excluded from analysis (642 disclosur es).

Figure 3. Geographic distribution of disclosures by production type.

32 For five of the six states with mandatory reporting requirements to FracFocus, reporting is required for hydraulic

fracturing operations on or after the regulatory effective date. For Texas, the reporting requirements apply to hydraulic

fracturing operations conducted at wells with drilling permits issued on or after the regulatory effective date.

33 There is typically a delay of one to three months between the fracture date and the date of required disclosure

reporting in states with mandatory reporting to FracFocus (Appendix E). The reporting delay may have led to artificially

low reporting rates for the months toward the end of the analysis (late 2012 and early 2013).Analysis of Data from FracFocus 1.0 March 2015

31 

### database is largely driven by disclosures in Texas, which has the largest percentage of disclosures

in the project database. In Texas, the number of disclosures per day increased by 89% after the

regulatory effective date for mandatory reporting to FracFocus. 34 

### A similar trend was found for

North Dakota, which had an 84% increase in disclosures per day after the regulatory effective date.

Opposite trends were observed for Colorado, Oklahoma, Pennsylvania, and Utah : the number of

disclosures per day for these states decreased after the regulatory effective date for mandatory

reporting to FracFocus. 35 Note: Analysis considered 37,888 disclosures that met selected quality assurance criteria , including: unique combination of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and with confirmed state

location. Disclosures tha t did not meet quality assurance criteria were excluded from analysis ( 642). During the timeframe of

this study, six states mandated reporting to FracFocus: Colorado, North Dakota, Oklahoma, Pennsylvania, Texas, and Utah

. Vertical lines in the figure indicate when mandatory reporting to FracFocus became effective

. Voluntary disclosures included

disclosures that fell into one of the following categories: disclosures from states with no reporting requirements, states wi th

reporting requirements that did not mandate reporting to FracFocus (i.e., states requiring disclosure to the state and states

requiring disclosure to either the state or FracFocus), or disclosures that had a fracture date prior to a state’s regulatory

effective date for ma ndatory reporti ng to FracFocus. A list of state disclosure requirements is provided in Appendix E.

Figure 4. Distribution of fracture dates in the project database.

0 500 1,000 1,500 2,000 2,500JanFebMarAprMayJunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOctNovDecJanFeb

2011 2012 2013Number of Disclosures

Fracture Date Voluntary

Mandatory Texas Colorado

North Dakota

Pennsylvania Utah Oklahoma

34 The number of d isclosures per day was calculated for the time periods before and after a state’s disclosure requirement

became effective. The number of disclosures with a fracture date between January 1, 2011, and a state's effective date (i.e.,

before regulations) was divided by the number of days in that period. The number of disclosures between the effective

date and February 28, 2013, (i.e., after regulations) was similarly divided by the number of days in that time period.

35 The number of disclosures per day decreased by 37% in Colorado, 19% in Oklahoma, 13% in Pennsylvania, and 21% in

Utah. In Oklahoma, the regulatory effective date for mandatory disclosures to FracFocus was January 1, 2013, which was

two months prior to the end of the time period of the study. This may account for the decrease in the number of

disclosures observed for Oklahoma, because well operators had 60 days to report to FracFocus.Analysis of Data from FracFocus 1.0 March 2015

32 

### Changes in the number of disclosures reported t o FracFocus per day or per month may be due to a

variety of factors, including fluctuations in the number of wells hydraulically fractured and shifts in

state reporting requirements as new regulations were adopted. Available information indicates that

the percentage of wells within a state reporting data to FracFocus increases when states have

mandatory reporting requirements to FracFocus. This may or may not relate to the increases and

decreases in disclosures per day discussed above, depending on other fa ctors that can influence the

number of wells hydraulically fracturing, including the price of oil and gas. Hansen et al. (2013)

compared the number of disclosures in FracFocus from Pennsylvania to the number of wells that

started drilling in the same year and found that the percentage of wells reporting to FracFocus

increased from 59% in 2011 to 85% in 2012, which coincides with mandatory reporting

requirements to FracFocus implemented by Pennsylvania in April 2012. A similar observation was

made by the Rai lroad Commission of Texas, which reported that, prior to the passage of reporting

regulations in Texas, well operators were voluntarily uploading data to FracFocus for about half of

all wells undergoing hydraulic fracturing in Texas ( Railroad Commission of Texas, 2015 ).

The observations from Hansen et al. (2013) and the Railroad Commission of Texas (2015) suggest

that the project database is likely incomplete, because the majority of the states with data in the

project database (14 out of 20) did not have mandatory reporting requirements to FracFocus

during the study timeframe. 36 

### For the six states that implemented mandatory reporting

requirements to FracFocus during the time period studied in this report

, the earliest regulatory

effective date was February 1 , 2012 (Texas), and the latest date was January 1, 2013 (Oklahoma).

Because the majority of disclosures in the project data base (58%) were reported in states without

mandatory reporting requirements to FracFocus or had fracture dates prior to regulatory effective

dates for mandatory reporting to FracFocus, the project database cannot be assumed to be

complete.



## Additive Ingredients

The project database contains 692 unique ingredients reported for base fl uids, proppants, and

additives in hydraulic fracturing fluids. 37 

### Of these, 598 ingredients are associated with valid

maximum fluid and additive concentrations (individual record values between 0 % and 100%).

Similarly large numbers of chemicals associated wi th hydraulic fracturing have been estimated

elsewhere. In a survey of 14 leading oil and gas service companies, Waxman et al. (2011) found that

the additives used contained 750 chemicals. Colborn et al. (2011) used information from MSDS for

additives used in the natural gas industry to compile an estimate of 632 chemicals used during

drilling and hydraulic fracturing of natural gas wells.

This section primarily summarizes ingredients reported in hydraulic fracturing fluid additives that

have purposes other than base fluid or proppant , but also includes ingredients identified as non

-

36 Eight of the 14 states had or implemented reporting requirements during the study’s timeframe that either required

reporting to the state or allowed reporting to the state or FracFocus. Six states had no reporting requirements during the

study’s timeframe.

37 Unique ingredients are defined by valid CASRN and chemical name.Analysis of Data from FracFocus 1.0 March 2015

33 

### aqueous base fluids (Section 3.2.1) and resin coatings for proppants

. 38 

### A nalyses focused primarily

on the ingredients in additives rather than the additives ( i.e., the trade name f ield) because

chemical information is more useful to assess toxicity, exposure, and therefore potential impacts on

drinking water resources. Additive s may be single

- ingredient additives

, as suggested by additive

concentrations of 100%, or they may contain several ingredients. Additives are added to a

hydraulic fracturing fluid to change the fluid’s properties. For example, some additives in the

fracturing fluid help manage viscosity for d elivery of proppant into the fractures

, while other

additives serve to minimize damage to the formation or maximize flow of oil or gas from the

formation to the well (Gupta and Valkó, 2007). Additives chosen for hydraulic fracturing fluids can

vary signifi cantly based on factors such as geologic conditions, well design, and operator or service

company preferences (Arthur et al., 2014; GWPC and ALL Consulting, 2009; Waxman et al., 2011).

The median number of unique additive ingredients per disclosure was 14 and, summarized by

state, ranged from nine in Virginia to 21 in New Mexico. Table 7 shows the median number of

unique additive ingredients per disclosure for the 20 states identified in the project database . The

median number of additive ingredients per di sclosure was 16 for oil disclosures and 12 for gas

discl osures (not shown in Table 7). The range of additive ingredients per disclosure, however, was

four to 28 (5th to 95th percentile) for the entire dataset

. A pparent differences between oil and gas

discl osures may not be statistically significant.



### 3.1.1. Reported Frequency and Fluid Concentrations of Additive Ingredients

The 20 most frequently reported additive ingredients were analyzed separately for oil and gas

disclosures in the project database. Tables 8 an d 9 list the most frequently reported chemicals for

hydraulic fracturing in oil and gas disclosures, respectively, with median and 5th and 95th

percentiles for maximum hydraulic fracturing fluid concentrations reported. 39 

### Median as well as 5th

and 95th perc entiles for the maximum concentrations of the chemicals in their respective additives

are also included in Table s 8 and 9. 40 

### Maximum ingredient concentrations (in hydraulic fracturing

fluids and additives) are reported as mass percents in Tables 8 and 9 to be consistent with

concentrations reported by operators to FracFocus 1.0 (Figure 1) , although volumes may be more

useful for understanding potential impacts on drinking water resources from releases of hydraulic

fracturing fluids or additives

. 41 

### Both m aximu m additive concentration s and fluid concentration s for

each additive ingredient may be important to consider when assessing potential impacts on

38 Resin coatings are added to proppants and en hance the ability of proppants to keep fractures open; resin coatings do

not function as proppants themselves.

39 If a n additive ingredient appeared more than once in a disclosure (e.g., the same solvent used in multiple additives),

then the maximum fluid c oncentrations were added. For example, methanol may be an ingredient in two additives on a

disclosure with maximum fluid concentrations of 0.1% and 0.05% by mass, respectively. The maximum fluid

concentration of methanol for this disclosure would be the su m of 0.1% and 0.05%, which is 0.15% by mass.

40 Maximum concentrations of ingredients in additives reflect the concentration for each individual ingredient record, not

the sum of the reported concentrations.

41 Mass percents could be converted to volumes b y assuming a density for total water volumes reported in the well header

table (Figure 1).Analysis of Data from FracFocus 1.0 March 2015

34 

### drinking water resources from hydraulic fracturing, because an accidental release of a relatively

small volume of a concentrated additive being stored on a well pad may have different potential

impacts than a release of a greater volume of hydraulic fracturing fluid with more dilute additive

ingredient concentrations.

Additive ingredients listed in Tables 8 and 9 were generally present in hydraulic fracturing fluids in

low concentrations. The medians of the maximum fluid concentrations of the frequently reported Table 7. Number of unique additive ingredients per disclosure , summarized by state

.

State Number of disclosures Number of additive ingredient s

per disclosure

Median 5th

percentile 95th

percentile

Alabama 55 10 10 10

Alaska 20 15 13 16

Arkansas 1,337 10 6 21

California 585 19 10 23

Colorado 4,561 13 5 23

Kansas 97 14 8 17

Louisiana 1,026 15 1 29

Michigan 14 19 10 29

Mississippi 4 14 11 23

Montana 193 16 9 38

New Mexico 1,115 21 7 31

North Dakota 1,989 15 4 33

Ohio 146 17 8 38

Oklahoma 1,810 12 5 30

Pennsylvania 2,419 10 4 18

Texas 16,405 15 4 30

Utah 1,253 17 7 23

Virginia 79 9 7 12

West Virginia 239 12 7 22

Wyoming 1,198 10 5 24

State Uncertain* 130 15 5 27

Entire Dataset 34,675 14 4 28

* State location did not pass state locational quality assurance criteria.

Note: Analysis considered 34,675 disclosures and 676,376 ingredient record s that met selected quality

assurance criteria , including: completely parsed; unique combination of fractu re date and API well

n umber; fracture date between January 1, 2011, and February 28, 2013; valid CASRN ; and valid

concentrations. Disclosures that did not meet quality assurance criteria (3,855 disclosures) or other,

query

- specific criteria were excluded f rom analysis

.Analysis of Data from FracFocus 1.0 March 2015

35 Table 8

. Twenty most frequently reported additive ingredients in oil disclosures , ranked by frequency of occurrence.

EPA

- standardized

chemical name CASRN Maximum concentration in

hydraulic fracturing fluid (% by mass) Maximum concentration in

additive (% by mass)

Number (%)

of disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Methanol 67

- 56

- 1 12,484 (72%) 0.022 0.00064 0.16 26,482 (7.7%) 30 0.39 100

Distillates,

petroleum,

hydrotreated light* 64742

- 47

- 8 10,566 (61%) 0.087 0.00073 0.39 15,995 (4.6%) 40 0.60 70

Peroxydisulfuric acid,

diammonium salt 7727

- 54

- 0 10,350 (60%) 0.0076 0.00028 0.067 12,723 (3.7%) 100 0.10 100

Ethylene glycol 107

- 21

- 1 10,307 (59%) 0.023 0.00086 0.098 12,281 (3.5%) 30 0.50 60

Hydrochloric acid 7647

- 01

- 0 10,029 (58%) 0.29 0.013 1.8 11,817 (3.4%) 15 2.9 50

Guar gum 9000

- 30

- 0 9,110 (52%) 0.17 0.027 0.43 9,316 (2.7%) 50 1.6 100

Sodium hydroxide 1310

- 73

- 2 8,609 (50%) 0.010 0.000050 0.075 10,300 (3.0%) 10 0.025 45

Quartz* † 14808

- 60

- 7 8,577 (49%) 0.0041 0.000040 12 12,636 (3.7%) 2.0 0.020 93

Water* † 7732

- 18

- 5 8,538 (49%) 1.0 0.0050 9.1 23,340 (6.7%) 67 15 97

Isopropanol 67

- 63

- 0 8,031 (46%) 0.0063 0.000070 0.22 11,975 (3.5%) 15 0.17 100

Potassium

hydroxide* 1310

- 58

- 3 7,206 (41%) 0.013 0.000010 0.052 8,050 (2.3%) 15 0.15 50

Glutaraldehyde 111

- 30

- 8 5,927 (34%) 0.0065 0.00027 0.020 6,211 (1.8%) 15 0.030 50

Propargyl alcohol 107

- 19

- 7 5,599 (32%) 0.00022 0.000030 0.0030 6,129 (1.8%) 5.0 0.0029 10

Acetic acid 64

- 19

- 7 4,623 (27%) 0.0047 0.000000 § 0.047 5,552 (1.6%) 30 0.82 100

2

- Butoxyethanol* 111

- 76

- 2 4,022 (23%) 0.0053 0.000000 § 0.17 5,096 (1.5%) 10 0.25 100

Solvent naphtha,

petroleum, heavy

arom.* 64742

- 94

- 5 3,821 (22%) 0.0060 0.000000 § 0.038 4,129 (1.2%) 5.0 0.00 35

Sodium chloride* 7647

- 14

- 5 3,692 (21%) 0.0071 0.000000 § 0.27 4,445 (1.3%) 25 0.0040 100

Ethanol* 64

- 17

- 5 3,536 (20%) 0.026 0.000020 0.16 4,178 (1.2%) 45 1.0 60

Citric acid 77

- 92

- 9 3,310 (19%) 0.0047 0.00016 0.024 3,491 (1.0%) 60 7.0 100

Phenolic resin 9003

- 35

- 4 3,109 (18%) 0.13 0.019 2.0 3,238 (0.94%) 5.0 0.94 20

* Chemical has a non

- normal distribution and the median may not represent the central tendency of the dataset as well as the median of a normally distributed dataset.

† See the text for a discussion of why water and quartz were included in the table.

§ Concentration is less than a millionth of a percentage by mass.

Note : Analysis considered 17,640 disclosures and 385,013 ingredient record s that met selected quality assurance criteria , including : completely parsed; unique combination

of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; valid CASRN ; and valid concentrations. Disclosures that did not meet

quality assurance criteria (2,268 disclosures) or other, query

- specific criteria were excluded from analysis.Analysis of Data from FracFocus 1.0 March 2015

36 Table 9. Twenty most frequently reported additive ingredients in gas disclosures , ranked by frequency of occurrence.

EPA

- standardized

chemical name CASRN Maximum concentration in

hydraulic fracturing fluid (% by mass) Maximum concentration in

additive (% by mass)

Number (%)

of disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Hydrochloric acid 7647

- 01

- 0 12,351 (73%) 0.078 0.0063 0.67 13,754 (5.3%) 15 2.7 60

Methanol 67

- 56

- 1 12,269 (72%) 0.0020 0.000040 0.053 19,074 (7.3%) 30 0.50 90

Distillates,

petroleum,

hydrotreated light* 64742

- 47

- 8 11,897 (70%) 0.017 0.0021 0.27 14,289 (5.5%) 30 3.1 70

Isopropanol 67

- 63

- 0 8,008 (47%) 0.0016 0.000010 0.051 10,326 (3.9%) 30 2.5 60

Water* † 7732

- 18

- 5 7,998 (47%) 0.18 0.000090 91 17,690 (6.8%) 63 5 100

Ethanol* 64

- 17

- 5 6,325 (37%) 0.0023 0.00012 0.090 7,062 (2.7%) 5.0 1.0 60

Propargyl alcohol 107

- 19

- 7 5,811 (34%) 0.000070 0.000010 0.0016 5,963 (2.3%) 10 0.0037 40

Glutaraldehyde 111

- 30

- 8 5,635 (33%) 0.0084 0.00091 0.023 5,827 (2.2%) 30 0.18 60

Ethylene glycol 107

- 21

- 1 5,493 (32%) 0.0061 0.000080 0.24 7,733 (3.0%) 35 1.0 100

Citric acid 77

- 92

- 9 4,832 (28%) 0.0017 0.000050 0.011 4,885 (1.9%) 60 30 100

Sodium hydroxide 1310

- 73

- 2 4,656 (27%) 0.0036 0.000020 0.088 5,642 (2.2%) 5.0 1.0 60

Peroxydisulfuric acid,

diammonium salt 7727

- 54

- 0 4,618 (27%) 0.0045 0.000050 0.045 6,402 (2.4%) 100 0.26 100

Quartz* † 14808

- 60

- 7 3,758 (22%) 0.0024 0.000030 11 4,729 (1.8%) 10 0.20 100

2,2

- Dibromo

- 3

- nitrilopropionamide 10222

- 01

- 2 3,668 (22%) 0.0018 0.000070 0.022 3,728 (1.4%) 100 10 100

Sodium chloride* 7647

- 14

- 5 3,608 (21%) 0.0091 0.000000 § 0.12 4,176 (1.6%) 30 1.0 40

Guar gum 9000

- 30

- 0 3,586 (21%) 0.10 0.00057 0.38 3,702 (1.4%) 60 1.6 100

Acetic acid 64

- 19

- 7 3,563 (21%) 0.0025 0.000000 § 0.028 3,778 (1.4%) 50 5.0 90

2

- Butoxyethanol* 111

- 76

- 2 3,325 (20%) 0.0035 0.000010 0.041 4,186 (1.6%) 10 3.0 40

Naphthalene* 91

- 20

- 3 3,294 (19%) 0.0012 0.0000027 0.0050 3,355 (1.3%) 5.0 0.0071 5.0

Solvent naphtha,

petroleum, heavy

arom.* 64742

- 94

- 5 3,287 (19%) 0.0044 0.000030 0.030 3,750 (1.4%) 30 0.026 30

* Chemical has a non

- normal distribution and the median may not represent the central tendency of the dataset as well as the median of a normally distrib uted dataset.

† See the text for a discussion of why water and quartz were included in the table.

§ Concentration is less than a mi llionth of a percentage by mass.

Note : Analysis considered 17,035 disclosures and 291,363 ingredient record s that met selected quality assurance criteria , including : completely parsed; unique combination

of fractu re date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; valid CASRN ; and valid concentrations. Disclosures that did not meet

quality assurance criteria (1,587) or other, query

- specific criteria were excluded from analysis.Analysis of Data from FracFocus 1.0 March 2015

37 

### additive ingredients, except for water, were less than 0.3% by mass of the fracturing fluid, and the

95th percentiles for maximum fluid concentration did not exceed 2.0%, except for w ater and

quartz. The sum of the maximum fluid concentrations for all additive ingredients in a disclosure,

excluding proppant and base fluid ingredients, was less than 1% by mass in approximately 80% of

disclosures. The median value for this sum was 0.43% by mass. The additive ingredient

concentrations observed in the project database appear to be consistent with published estimates

that report that the total concentration of all additive ingredients constitutes approximately 1% to

2% or less of the fractur ing fluid (GWPC and ALL Consulting, 2009; Lee et al., 2011).

Eighteen of the 20 most frequently reported additive ingredients were common to hydraulic

fracturing fluids used in both the oil and gas disclosures analyzed. In particular, methanol,

hydrochlori c acid, and hydrotreated light petroleum distillates were among the additive ingredients

most frequently reported for both oil and gas disclosures in the project database. Among the entire

dataset, methanol was reported in 71% of disclosures (24,753 out of 34,675), hydrochloric acid in

65% (22,380 disclosures), and hydrotreated light petroleum distillates in 65% (22,463

disclosures). Methanol was associated with additives such as corrosion inhibitors and surfactants,

while reported purposes for additives th at contain hydrochloric acid included serving as a scale

control agent, controlling iron, serving as a solvent, and a more general designation of “acid” or

“acidizing” (see Section 3.1.2 for further discussion). Hydrochloric acid is known to be commonly

us ed to clean the well perforations (Economides and Baumgartner, 2008).

Methanol, hydrochloric acid, and light petroleum distillates were each reported in 70% or more of

gas disclosures (Table 9). The next most frequently reported additive ingredient for gas disclosures

(isopropanol) was reported in less than 50% of gas disclo sures. This suggests that methanol,

hydrochloric acid, and hydrotreated light petroleum distillates were consistently used in hydraulic

fracturing fluids for gas wells between January 2011 and February 2013 . In contrast, additive

ingredients reported for o il disclosures did not show a similar pattern : seven additive ingredients

were each reported in 50% or more of oil disclosures, with only one additive ingredient ( methanol)

reported in more than 70% of oil disclosures (Table 8)

.

Maximum fluid concentrati ons (medians, 5th and 95th percentiles) for the most frequently

reported additive ingredients appear to be greater in disclosures for oil well s than gas wells (Tables

8 and 9). For example, the median of the maximum fluid concentration for hydrochloric aci d

reported for oil disclosures was 0. 29 % by mass, compared to 0 .078 % for gas disclosures. The range

of observed maximum fluid concentrations for hydrochloric acid was also an order of magnitude

l arger in oil disclosures, 0.013 % to 1.8% b y mass (5th to 95th percentile), comp ared to gas

disclosures (0.0063 % to 0.67% by mass). Similar to hydrochloric acid, reported maximum fluid

concentrations for methanol were an order of magnitude greater in oil disclosures, which ranged

from 0.00064 % to 0.16% by mass (5th t o 95 th percentile) , than in gas disclosures, which ranged

from 0. 000040 % to 0.053% by mass.

Water and Quartz as Additive Ingredients. Water was commonly reported as an ingredient in

additives as well as being listed as a base fluid. Quartz, the proppant i ngredient most commonly

reported, was also reported as an ingredient in other additives. Both Table s 8 and 9 list water and

quartz among the 20 most frequently reported additive ingredients used in hydraulic fracturingAnalysis of Data from FracFocus 1.0 March 2015

38 

### fluids. Water was reported as an addi tive ingredient in 49% of oil disclosures and 47% of gas

disclosures, and quartz was reported as an additive ingredient in 49% and 22% of oil and gas

disclosures, respectively.

The 95th percentile values observed for maximum fracturing fluid concentrations of water and

quartz as additive ingredients were larger than expected : 9.1 % and 12% by mass in oil disclosures

and 91 % and 11% by mass in gas disclosures, respectively (Table s 8 and 9). The larger values were

more reflective of maximum fluid concentrations associated with base fluids ( Section 3.2 ) and

proppants ( Section 3.3 ) and may have been included in the analys e s of additive ingredients in oil

and gas disclosures due to mislabeled or unlabeled purposes in the project database or original P DF

disclosures. 42 

### For example, 99 ingredient records with valid concentrations contained no purpose

information for quartz; of these, 75 had trade names that were readily identifiable as proppants.

Ultimately, the small number of disclosures with unidentifi ed purposes was included to avoid any

assumptions that may have introduce d bias in the results.

Diesel Fuels

. To evaluate the use of diesel fuel in hydraulic fracturing fluids, the project database

was analyzed for any of the following CASRNs: 43



###  68334

- 30

- 5 : Fuels, diesel

 68476

- 30

- 2 : Fuel oil no. 2

 68476

- 31

- 3 : Fuel oil no. 4

 68476

- 34

- 6 : Fuels, diesel, no. 2

 8008

- 20

- 6 : Navy fuels JP

- 5; kerosene 44



### T hree of the five CASRNs were identified in the project database : 68334

- 30

- 5, 68476

- 34

- 6, and

8008

- 20

- 6. The CASRNs were r eported in 302 gas disclosures (1.7% of 17,594 gas disclosures with

parsed ingredients and valid CASRNs) and 40 oil disclosures (0.22% of 18,363 oil disclosures with

parsed ingredients and valid CASRNs). 45 

### No disclosures reported use of more th an one of these five

CASRNs

.

The most frequently reported diesel fuel CASRN was 8008

- 20

- 6, with 281 disclosures, 270 of which

were for gas disclosures

. Fifty

- seven disclosures listed 68476

- 34

- 6, and four disclosures included

68334

- 30

- 5. The state with the largest number of disclosures listing a diesel fuel CASRN was

Arkansas, with 173 disclosures (primarily 8008

- 20

- 6 ), followed by New Mexico (54 disclosures),

Pennsylvania (43 disclosures), and Texas (30 disclosures).

42 The database filter applied to the data query excluded additive ingredients associated with base fluids and proppants or

their synonyms.

43 The five CASRNs were use d to define diesel fuels in the Permitting Guidance for Oil and Gas Hydraulic Fracturin g

Activities Using Diesel Fuels : Underground Injection Control Program Guidance #84 (US EPA, 2014b).

44 Navy fuels JP

- 5 (CASRN 8008

- 20

- 6) is referred to as kerosene in the Permitting Guidance for Oil and Gas Hydraulic

Fracturing Activities Using Diesel Fuels: Underground Injection Control Program Guidance #84 (US EPA, 2014b).

45 An additional 20 disclosures ( 19 gas and 1 oil) that did not pass QA criteria reported two of the same three compounds.Analysis of Data from FracFocus 1.0 March 2015

39 

### 3.1.2. Additive Purposes

Op erators generally report ed purposes for each additive (i.e., trade name ) listed on a disclosure

(Figure 1). 46 

### The purpose describes the function of the additive in the hydraulic fracturing fluid

,

rather than the function of individual ingredients in the add itive

. In the project database, additive

purposes are assigned to each ingredient in the additive. Thus, regardless of whether a particular

ingredient serves as an active or inactive ingredient in an additive, its purpose as listed in the

database will be the same as that reported by the operator for the additive itself. Information

submitted to FracFocus neither indicates whether chemicals are active or inactive ingredients nor

the specific purpose a given ingredient serves in the additive.

The project dat abase developed for this study indicated a median number of 10 additives per

disclosure. Commonly cited estimates of the numbers of additives used for hydraulic fracturing

suggest three to 12 such additives, serving a variety of purposes (GWPC and ALL Cons ulting, 2009).

The number of additives used depends upon the specifics of the well in addition to operator

practices (Carter et al., 2013).

Additive ingredients are often associated with multiple purposes in the project database, because

different additiv es may have similar ingredients. Table 10 provides a list of the most commonly

reported purposes for additives that contain the most frequently reported additive ingredients

listed in Tables 8 and 9

.

Some additive types (as identified by purpose) were ass ociated with large numbers of ingredients

. For example, in the general category of biocides, there were 197 unique ingredients (as identified

by CASRNs), and 309 trade names for biocide additives . Similarly, 177 ingredients and 277 trade

names were found i n the project database for gelling agent and gel stabilizer additives. However,

because of parsing difficulties from variations in reporting styles , some additive purpose

assignments are likely to be erroneous. Therefore, the data are likely to represent o verestimates of

the total numbers of chemicals associated with various purpose s . Suspicious ingredient

- purpose

associations generally occur in one or two ingredient records each; therefore, greater frequency of

reporting for a particular additive purpose and ingredient combination in the project database

allows for greater confidence that the results reflect actual associations. Nonetheless, the data

indicate that a number of additives are us ed for a given purpose and that many of these additives

contain several ingredients.



### 3.1.3. Comparing Variability of Additive Ingredients in Selected Counties

The summary of additive ingredients reported for the entire dataset provided in Table s 8 and 9

may be he lpful in determining large

- scale similarities across the country. D iversity in additive

ingredients observed in the project database, however, implies that smaller

- scale aggregation of the

46 Appendix F contains a list of additive purpose categories identified from the project database and identifies the number

of disclosures containing additives for ea ch purpose category.Analysis of Data from FracFocus 1.0 March 2015

40 

### data may provide useful information on the composition of hydraulic fracturing fluids at more local

scales (e.g., states and counties) . Five counties were selected to illustrate diversity in additive

ingredients at small scales. Disclosures used in this analysis are from Andrews County, Texas; Table 10. F requently reported additive ingredients and commonly listed purposes for additives that contain the

ingredients.

EPA

- standardized chemical name CASRN Purposes c ommonly associated with additives

containing the ingredients *

2,2

- Dibromo

- 3

- nitrilopropionamide 10222

- 01

- 2 Biocide

2

- Butoxyethanol † 111

- 76

- 2 Surfactant, corrosion inhibitor, non

- emulsifier

Acetic acid 64

- 19

- 7 Buffer, iron control

Citric acid 77

- 92

- 9 Iron control

Distillates, petroleum,

hydrotreated light † 64742

- 47

- 8 Friction reducer, gelling agent, crosslinker

Ethanol 64

- 17

- 5 Surfactant, biocide

Ethylene glycol 107

- 21

- 1 Crosslinker, scale inhibitor, corrosion inhibitor,

friction reducer

Glutaraldehyde 111

- 30

- 8 Biocide

Guar gum 9000

- 30

- 0 Gelling agent

Hydrochloric acid 7647

- 01

- 0 Acidizer, solvent, scale dissolver, perforation

breakdown

Isopropanol 67

- 63

- 0 Corrosion inhibitor, non

- emulsifier, surfactant

Methanol 67

- 56

- 1 Corrosion inhibitor, surfactant, non

- emulsifier, scale

inhibitor, biocide, crosslinker

Naphthalene † 91

- 20

- 3 Surfactant, non

- emulsifier, corrosion inhibitor

Peroxydisulfuric acid,

diammonium salt 7727

- 54

- 0 Gel breaker

Phenolic resin 9003

- 35

- 4 Proppant (resin coating)

Potassium hydroxide* 1310

- 58

- 3 Crosslinker, buffer

Propargyl alcohol 107

- 19

- 7 Corrosion inhibitor

Quartz † § 14808

- 60

- 7 Breaker, gelling agent, scale inhibitor, crosslinker,

biocide, corrosion inhibitor, viscosifier

Sodium chloride † 7647

- 14

- 5 Breaker, friction reducer, scale inhibitor, clay

control, biocide

Sodium hydroxide 1310

- 73

- 2 Crosslinker, biocide, buffer, scale inhibitor

Solvent naphtha, petroleum,

heavy arom. † 64742

- 94

- 5 Surfactant, non

- emulsifier, inhibitor, corrosion

inhibitor

Water †§ 7732

- 18

- 5 Acid, biocide, clay control, scale inhibitor, iron

control, breaker, crosslinker, buffer, surfactant,

friction reducer

* Definitions of additive purposes are included in the Glossary.

† Chemical has a non

- normal distribution and the median may not represent the central tendency of the dataset as well

as the median of a normally distributed dataset.

§ See Section 3.1.1 for a discussion of why water and quartz were included in the table.

Note: Analysis considered 34,675 disclosures and 676,376 ingredient record s that met selected quality assurance criteria

, including: completely parsed; unique combination of fracture date and A PI well n umber; fracture date between January

1, 2011, and February 28, 2013; valid CASRN; and valid concentrations. Disclosures that did not meet quality assurance

criteria (3,855 disclosures) or other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

41 

### Bradford County, Pennsylvania; Dunn County, North Dakota; Garfield County, Colorado; and Kern

County, California (Table 11) . The five counties displayed a range of geography, geology, and

production type, and t he number of disclosures for each of these counties exceeded the 90th

percentile for the entire dataset (288 disclosures per county)

. The relatively large number of

disclosures per county illustrated the extent of oil and gas development in these areas dur ing the

study time period, and allowed selection of a dataset large enough to increase confidence in the

results of the analysis.

Generally, comparison s of additive ingredients across the five counties show ed less similarity than

the comparison of additive ingredients between each county and the entire dataset . The 20 most

frequently reported additive ingredients for each county (Appendix G) we re compared with the

other selected counties and with the entire dataset. 47 

### The number of frequently reported additive

ingredients in common between datasets was expressed as a percentage of the total number of

frequently reported additive ingredients using the following equation:

Percentage of Similarity = Number of additive ingredients in common between County A and County B

Average number of additive ingredients in Counties A and B



### The denominator for the above equation was 20 unless two additive ingredien ts were tied in rank

in one of the counties. The percentage of similarity in additive ingredients between pairs of

counties ranged from 15 % to 65%, as shown in Table 12. Overlap with the twenty most frequently

reported additive ingredients for the entire d ataset ranged from 35 % to 85%. This suggests a

degree of variability as would be expected given factors such as production type, geology, and

operator preference. However, the 60 % to 85% similarity with the entire dataset shown by four of

the counties (exc luding Kern County ) also suggests that certain additive ingredients were

commonly used in hydraulic fracturing fluids in disparate parts of the country. Similarity in additive

ingredients across counties is consistent with the notion that similar factors i nfluence the

composition of hydraulic fracturing fluid s . Similarity may also be influenced by economics and the

availability of additives at local or regional scale s

. P atterns in additive ingredients could be found

47 Some additive ingredients may overlap between two counties

, but fall below the twenty most frequently reported

chemicals on a list. Table 11. Counties selected to illustrate diversity in additive ingredients at small scales

.

County , State Sedimentary

basi n * P roduction

type Number of

disclosures Number of

operators

Andrews County, Texas Permian 98% oil 1,180 39

Bradford County,

Pennsylvania Appalachian 100% gas 513 6

Dunn County, North Dakota Williston 100% oil 334 18

Garfield County, Colorado Uinta

- Piceance 99% gas 1,362 9

Kern County, California San Joaquin 100% oil 677 6

* Sedimentary basins associated with oil and gas shale plays ( US EIA, 2011a ).

Note: Analysis considered 4,066 disclosures that met selected quality assurance criteria , including: unique

combination of fracture date and API well n umber; fracture date between Janu ary 1, 2011, and February 28, 2013;

with confirmed state location; and with confirmed county location. Disclosures that did not meet quality assurance

criteria (142 disclosures) or other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

42 

### by performing spatial analysis on formulations or select ed additive ingredients of interest , al though

these types of analyses were not conducted in this study. Among the five counties, Kern County was

notably less similar to the other counties and to the entire dataset than the other four counties.

Fewer disclo sures from Kern County used surfactants than the other two oil

- producing counties.

Disclosures from Kern County also show ed less use of friction reducers and non

- emulsifiers.

The percentage of similarity was found to be greater between the selected counti es and their states

(73% to 95% similarity; data not shown) than between the selected counties and the entire dataset.

This suggests that additive ingredient information compiled at the state level may provide some

useful insights into the composition of h ydraulic fracturing fluid s at the county level.



## Base Fluids

Base fluids are the fluids into which additives and proppants are mixed to create the fracturing

fluid. More than 93% of disclosures in the project database appear to use water as a base fluid. 48

, 49



### The median maximum reported concentration of water in hydraulic fracturing fluid was 88% by

mass, with a range of 68 % to 99% (5th and 95th percentile), suggesting its primary use as a base

fluid. 50

48 In this report, the term “water use” refers to the volume of water used for a hydraulic fracturing job as reported by

operators in the total water volume field of the well header table of a FracFocus disclosure; it does not refer to

withdrawals from a water source. The determination of water used as a base fluid was based on disclosures that include

at least one water ingredient record with a maximum fluid concentration greater than or equal to 1% by mass (Section

2.3.1)

.

49 Disclosures that met criteria for unique combination of fracture date and API well number; fracture date between

January 1, 2011, an d February 28, 2013 ; complet ely pars ed; with a valid maximum fracturing fluid concentration greater

than or equal to 1% by mass; and having “water” as a term in the trade name or chemical name field.

50 The total mass of fracturing fluid includes the masses of base fluids, additives, and proppants. Therefore, a fracturing

fluid with 88% by mass of water would be composed of approximately 12% proppant and additive ingredients by mass

. Table 12. Comparison of twenty most fr equently reported chemicals among selected counties.

County, State Percentage of similarity (%)

Andrews, TX* Dunn, ND* Kern, CA* Bradford, PA † Garfield, CO †

Andrews, TX* 49% 35% 65% 45%

Dunn, ND* 49% 39% 34% 39%

Kern, CA* 35% 39% 20% 15%

Bradford, PA † 65% 34% 20% 60%

Garfield, CO † 45% 39% 15% 60%

Entire Dataset 85% 63% 35% 65% 60%

* >98% of disclosures in county specify oil production

† >99% of disclosures in county specify gas production

Note: Analysis considered 3,622 disclosures and 61,502 ingredient record s that met selected quality assurance

criteria , including: completely parsed; unique combination of fracture date and API well n umber; fracture date

between January 1, 2011, and February 28, 2013; with confirmed state location ; with confir med county location;

valid CASRN ; and valid concentrations. Disclosures that did not meet quality assurance criteria (586 disclosures) or

other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

43 

### Data from the project database were compiled to assess vo lumes and sources of water used as base

fluids, as well as the frequency with which gases and hydrocarbons were used to either augment

water

- based fracturing fluids or to provide non

- aqueous alternative fracturing fluids. 51



### 3.2.1. Use of Non

- Aqueous Fluids in Base Fluid s

Non

- aqueous fluids

, such as gases and hydrocarbons

, were reported to be used alone or blended

with water to form a base fluid in 761 disclosures

. 52 

### M ore than 96% of these disclosures reported a

base fluid consisting of a blend of non

- aqueous fluids and water. Table 13 describes the frequency

of reporting and maximum concentrations for non

- aqueous base fluid ingredients , and Table 14

shows the numbers of disclosures that reported non

- aqueous base fluid ingredients by state. 53 

### Non

aqueous base fluid ing redients were most frequently reported in disclosures from Colorado, New

Mexico, and Texas.

Liquid nitrogen and carbon dioxide were the most frequently observed non

- aqueous ingredients

combined with water to form the base fluid. These gas

- water blends are used by operators to

generate foams and energized fluids. 54 

### Using gas in base fluid s reduces water use and thus reduces

contact between water and the formation, making these fluid systems useful in water

- sensitive

formations. Energized fracturing fluids al so promote flowback by expanding when the well is

produced (Friehauf and Sharma, 2009; Gupta and Hlidek, 2010; Gupta et al., 1997).

Liquid n itrogen was reported in 643 (84%) of the disclosures identifying non

- aqueous fluid

ingredients , with a median maximum fluid concentration of 16% by mass (Table 13). The greatest

reported use of liquid nitrogen was in New Mexico, with 296 disclosures (Table 14). Among the

disclosures that reported liquid nitrogen as a base fluid ingredient , 519 of the 643 were for gas

producing wells and 124 were for oil

- producing wells. The median maximum fluid concentration of

water in disclosures that reported liquid nitrogen in addition to water was 59% by mass. Among

disclosures that listed liquid nitrogen and water as base flu id ingredients, the median volume of

water reported was approximately 77,000 gallons.

Carbon dioxide was listed in 83 disclosures identifying non

- aqueous base fluid ingredients (11%),

with a median maximum fluid concentration of 32% by mass (Table 13). Of the 83 disclosures that

listed carbon dioxide as a base fluid ingredient, 73 were for gas

- producing wells. The greatest

51 The analysis does not account for brines formulated by the operator throu gh the addition of salts (e.g., potassium

chloride or sodium chloride) to water.

52 2.2% of 34,675 unique disclosures that met the date criterion and that had parsed ingredients with valid CASRNs and

valid maximum concentrations. Disclosures reporting gas or hydrocarbon ingredients in their base fluids were identified

through the presence of terms determined to be synonymous with “base fluid” in the purpose field of an additive and

through the presence in the ingredient field of ce rtain chemical names identified through preliminary queries. Based on a

preliminary analysis, ingredients that made up less than 1% by mass of the hydraulic fracturing fluid were excluded from

this analysis ( Section 2.3.1 ). To determine water use in these disclosures, all disclosures identifying the use of a non

aqueous fluid were searched for the presence of “water” in the trade name field or in the chemical name field, specifying a

maximum fluid concentration greater than or equal to 1% by mass

.

53 Because hydrocarbons were generally reported in combinations, one disclosure may be represented in more than one

row of Table 7

, and values in the columns cannot be totaled.

54 Foams consist of gas volumes greater than 53% by volume ( generally 65 % to 80% gas ) ; ene rgized fluids contain less

than 53% gas by volume, with typical volumes about 20 % to 30% gas (Gupta and Valkó, 2007; Montgomery, 2013).Analysis of Data from FracFocus 1.0 March 2015

44 Table 13. Non

- aqueou s ingredients reported in base fluids.

EPA

- standardized

chemical name CASRN Maximum concentration in

hydraulic fracturing fluid (% by mass) Maximum concentration in

additive (% by mass)

Number ( % ) of

d isclosures Median 5 th

percentile 95 th

percentile Number (% )

of ingredient

records Median 5 th

percentile 95 th

percentile

Nitrogen, liquid 7727

- 37

- 9 643 (84%) 16 3.8 30 643 (80%) 100 25 100

Carbon dioxide 124

- 38

- 9 83 (11%) 32 11 46 83 (10%) 100 100 100

Petroleum distillates 8002

- 05

- 9 18 (2.4%) 46 29 67 18 (2.2%) 100 100 100

Propane 74

- 98

- 6 15 (2.0%) 63 1.6 79 16 (2.0%) 100 2.0 100

Isobutane 75

- 28

- 5 12 (1.6%) 29 8.0 52 13 (1.6%) 50 10 100

Butane 106

- 97

- 8 10 (1.3%) 2.2 1.5 59 11 (1.4%) 80 36 100

Hexane 110

- 54

- 3 4 (0.53%) 14 11 15 4 (0.50%) 20 18 20

Pentane 109

- 66

- 0 4 (0.53%) 9.8 5.8 14 4 (0.50%) 13 10 19

Butene 25167

- 67

- 3 3 (0.39%) 25 8.1 49 3 (0.37%) 65 34 65

1

- Propene 115

- 07

- 1 2 (0.26%) 3.0 1.2 4.8 2 (0.25%) 5.0 5.0 5.0

2

- Methylbutane 78

- 78

- 4 2 (0.26%) 16 14 18 2 (0.25%) 25 25 25

Benzene 71

- 43

- 2 2 (0.26%) 3.3 2.8 3.7 2 (0.25%) 5.0 5.0 5.0

Ethane 74

- 84

- 0 2 (0.26%) 2.3 1.6 3.1 3 (0.37%) 2.0 2.0 9.2

Ethylene 74

- 85

- 1 1 (0.13%) 2.1 2.1 2.1 1 (0.12%) 10 10 10

Methane 74

- 82

- 8 1 (0.13%) 2.1 2.1 2.1 1 (0.12%) 10 10 10

White mineral oil,

petroleum 8042

- 47

- 5 1 (0.13%) 12 12 12 1 (0.12%) 100 100 100

Note : Analysis considered 34,675 disclosures and 676,376 ingredient record s that met selected quality assurance criteria , including : completely parsed; unique

combination of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; valid CASRN ; and valid concentrations. Disclosures that

did not meet quality assurance criteria (3,855) or other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

45 Table 14. Us e of non

- aqueous ingredients in base fluid s, summarized by state

.

EPA

- standardized

chemical name Number of disclosures

CO LA MI ND NM OH OK PA TX UT VA WY State

Uncertain* Total

Nitrogen, liquid 150 2 296 15 5 146 18 4 6 1 643

Carbon dioxide 38 1 1 3 1 1 5 15 18 83

Petroleum distillates 18 18

Propane 6 9 15

Isobutane 1 11 12

Butane 5 5 10

Hexane 4 4

Pentane 4 4

Butene 3 3

1

- Propene 2 2

2

- Methylbutane 2 2

Benzene 2 2

Ethane 2 2

Ethylene 1 1

Methane 1 1

White mineral oil,

petroleum 1 1

* State location did not pass state locational quality assurance criteria.

Note : Analysis considered 34,675 disclosures and 676,376 ingredients that met selected quality assurance criteria , including: completely parsed; unique combination

of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; valid CASRN , and valid chemical concentrations. Disclosures that

did not meet quality assurance criteria (3,855 disclosures) or other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

46 

### reported use of carbon dioxide was in Colorado, with 38 disclosures (Table 14). The median

maximum fluid concentration of water in disclosures that reported carbon dioxide in addition to

water was 61% by mass. Among disclosures that listed carbon dioxide and water as base fluid

ingredients, the median volume of water reported was approximately 40,000 gallons.

Hydrocarbons can be used with water to create emulsions to control fluid loss in low-permeability

gas-producing formations (Penny, 1982). Petroleum distillates and water were reported as the base

fluid in 17 disclosures located in Texas (median maximum fluid concentrations of 44% by mass for

petroleum distillates and 32% by mass for water). Among disclosures that listed petroleum

distillates and water as base fluid ingredients, the median volume of water reported was

approximately 11,000 gallons.

Although most hydraulic fracturing fluids described in the project database indicated water as all or

part of the base fluid, a small number of disclosures reported entirely non-aqueous bas fluids. Nonaqueous base fluids, including those based on hydrocarbons or alcohols, may be used in watersensitive formations or in oil-wet formations (DeVine et al., 2003; Gupta et al., 1997; Rae and Di

Lullo, 1996). Hydrocarbon mixtures were reported as base fluids in 18 disclosures (2.4% of 761

disclosures that reported non-aqueous bas fluids); 12 disclosures were reported in Texas, and six

disclosures were reported in Colorado. Eleven disclosures in Texas reported oil production, and the

six disclosures in Colorado and one from Texas reported gas production. Among disclosures

reporting hydrocarbon mixtures as base fluids, propane was identified as the primary base fluid

ingredient in 10 disclosures, with a median maximum fluid concentration of 64% by mass. 55 

### Other

disclosures reported other mixtures of the hydrocarbons listed in Table 13. The total water volume

field was blank on the 18 disclosures that reported only hydrocarbons as base fluids.



### 3.2.2. Cumulative Total Water Volumes

Data from the project database indicate that nearly 92 billion gallons of water were used for

hydraulic fracturing throughout the time period studied: 36 billion gallons in 2011, 52 billion

gallons in 2012, and 3.8 billion gallons in the first two months of 2013. Cumulative total water

volumes were calculated for each county with disclosures in the project database and are shown in

Figure 5. 56 

### Counties with the greatest reported cumulative total water volumes are clustered in

areas of northeastern Pennsylvania, northern Colorado, western North Dakota, and parts of Texas.

Cumulative total water volumes should be considered lower limit estimates of water use for

hydraulic fracturing within a county, as the information in the project database from counties in a

state with voluntary reporting may be incomplete

. The estimates of cumulative total water volumes

may be useful, when paired with local information on water availability and total water use, for

identifying areas of the country that may be vulnerable to water stress resulting from hydraulic

fracturing.

55 Butanes were also reported as base fluids in these 10 disclosures, with a median maximum fluid concentration of 3.4%

by mass. One disclosures also reported 1-propene, with a maximum fluid concentration of 4.8% by mass.

56 Appendix H lists cumulative total water volumes for each county as well as per-disclosure water volumes.Analysis of Data from FracFocus 1.0 March 2015

47 

### Given the common use of water in hydraulic fracturing fluids, it is expected that the greatest

cumulative total water volumes would be found in counties with a large number of disclosures in

the project database (Figure 2). 57 

### For example, nine of the 20 counties with the largest cumulative

total water volumes are also in counties with a large number of disclosures

. Cumulative total water

volumes for these nine counties ranged from 1.3 billion gallons in Gonzales County (344

disclosures) to 3.9 billion gallons in Dimmit County (715 disclosures). For context, Appendix H,

shows that nearly half of the 406 counties represented in the project database have 10 or fewer

disclosures.

State-level cumulative total water volumes were typically greatest in states with a large number of

disclosures, as shown in Table 15. For example, Texas had both the greatest reported cumulative

total water volume (approximately 45 billion gallons) and the largest number of disclosures Note: S hale basins are those sedimentary basins associated with oil and gas shale plays (US EIA, 2011a). The shale basins offer

basic geologic context for the location of a disclosure; well disclosures likely represent more oil and gas producing formati ons

than only shale formations. Analysis considered 37,888 disclosures that met selected quality assurance criteria , including:

unique combination of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and

with confirmed state location. Disclosures that did not meet quality assurance criteria were excluded from analysis (642).

Figure 5. Cumulative total water volumes, summarized by county

.

57 The relationship between the number of disclosures and reported water volumes is shown further in Appendix H,

which presents, for each county, the number of unique disclosures meeting the date and water volume criteria, the

cumulative water use, and water volumes per disclosure (median, 5th and 95th percentiles).Analysis of Data from FracFocus 1.0 March 2015

48 

### (17,934; 47% of disclosures that met the analysis criteria ). Pennsylvania had the third largest

number of disclosures (2,467; 6.5% of disclosures) and the second largest cumulative total water

volume (approximately 1 1 billion gallons). The c umulative total water volume was the smallest in

Alabama ( approximately 2 .1 million gallons, 55 disclosures).

Cumulative total water volumes for a few states (e.g., Arkansas, Louisiana, Mississip pi, Ohio, and

West Virginia) were larger than what might be expected based solely on the numbers of disclosures

included in the project database . This is consistent with relatively large volumes of water reported

per disclosure in these states

, as reflected by median, 5th percentile, and 95th percentile values Table 15. Total w ater volumes, summarized by state

.

State Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure (gallons)

Median 5th

percentile 95th

percentile

Texas 17,934 44,5 80

, 000

, 000 1,413,287 26,006 7,407,116

Pennsylvania 2,467 10,60 0

, 000

, 000 4,184,936 1,092,739 7,475,493

Arkansas 1,444 7, 500

, 000

, 000 5,277,890 2,681,465 7,484,091

Oklahoma 1,898 6,666,0 00

, 00 0 2,578,947 114,870 8,288,041

Colorado 4,924 6,65 2

, 000

, 000 463,659 103,906 4,327,068

Louisiana 1,031 5,408,0 00

, 000 5,148,696 277,540 8,942,170

North Dakota 2,235 4,789, 000

, 000 2,019,513 557,740 3,685,402

West Virginia 277 1,39 4

, 000

, 000 5,012,238 2,500,529 7,889,759

Wyoming 1,449 1,109, 000

, 000 306,246 5,503 3,110,272

New Mexico 1,159 787, 700

, 000 172,452 22,130 2,851,323

Ohio 146 614,2 00

, 000 3,887,499 2,526,398 7,442,826

Utah 1,421 534,4 00

, 000 303,424 35,070 1,056,654

Montana 213 337,500, 000 1,469,839 216,578 3,197,594

Kansas 134 145, 200

, 000 1,421,591 9,866 2,448,300

California 718 94,4 40 ,0 00 77,154 18,684 356,453

Michigan 15 55,100,0 00 33,306 15,722 15,127,125

Mississippi 4 35,1 40

, 000 9,173,624 4,322,108 12,701,054

Alaska 37 13,150, 000 88,448 36,437 435,638

Virginia 77 3,02 1

, 000 33,474 13,322 96,684

Alabama 55 2,065, 000 37,691 23,602 51,651

State Uncertain * 158 488, 100

, 000 2,770,090 80,067 6,945,958

Entire Dataset 37,796 91,8 10

, 000

, 00 0 1,508,724 29,526 7,196,702

* State location did not pass state locational quality assurance criteria.

Note: Analysis considered 37,796 disclosures that met selected quality assurance criteria , including: unique combination

of fracture date and API well n umber; fracture date between J anuary 1, 2011, and February 28, 2013; and criteria for

water volumes. Disclosures that did not meet quality assurance criteria were excluded from analysis (734).Analysis of Data from FracFocus 1.0 March 2015

49 

### (Table 15; see Section 3.2.3 for more discussion). The high per

- disclosure total water volumes may

reflect well length, geologic characteristics , and operator practices in these areas.



### 3.2.3. Tot al Water Volumes per Disclosure

Some factors that influence water volumes used for hydraulic fracturing include formation type,

total measured depth of the well, length of the production interval of the well (which can be

horizontal), fracturing fluid prop erties, and the design of the fracturing job (Nicot and Scanlon,

2012). Hydraulic fracturing is sometimes referred to as low

- volume or high

- volume depending on

the relative amount of fluid used to fracture the target rock formation . Low

- volume hydraulic

fr acturing, typically conducted in vertical wells, can require between 20,000 and 80,000 gallons of

water or other fluid (NYSDEC, 1992). Hydraulic fracturing of a coalbed methane reservoir may

require 50,000 to 350,000 gallons per well (Holditch, 1993; Jeu e t al., 1988; Palmer et al., 1991;

Palmer et al., 1993).

High

- volume hydraulic fracturing for wells located in low permeability formations such as shales

can require millions of gallons of water (GWPC and ALL Consulting, 2009; Lee et al., 2011; Nicot and

S canlon, 2012) and often include long horizontal well segments. Water volumes in the Marcellus

Shale, for example, have been reported to range from 3 to more than 5 million gallons per well

(Aminto and Olson, 2012)

. Vengosh et al. (2014) report that up to 1 3 million gallons of water is

needed per well for hydraulic fracturing of unconventional reservoirs. The New York State

Department of Environmental Conservation (2011) estimates that a multi

- stage fracturing

operation for a well with a 4,000

- foot long late ral (the horizontal segment of the well) would

typically involve between 8 and 13 stages and use 300,000 to 600,000 gallons of water per stage

, for a total of 2.4 to 7.8 million gallons per well

.

The project database provides a snapshot of total water vol umes reported on a per

- disclosure basis,

although interpretation is somewhat limited by lack of information on the total measured depth of

the well (which can be greater than the true vertical depth) and the length of the production

interval. 58 

### Figure 6 sho ws the median total water volume per disclosure for each county in the

project database. The median total water volume per disclosure in the project database was

approximately 1.5 million gallons, with a range of reported total water volumes of nearly 30,0 00

gallons to almost 7.2 million gallons (5 th to 95 th percentile). The wide range likely reflects

hydraulic fracturing practices that include low

- volume stimulation of vertical wells, high

- volume

fracturing of horizontal wells in shales and tight sands, a n d fracturing in coalbed methane plays.

Gas disclosures reported a median total water volume of approximately 2.9 milli on gallons, and oil

disclosures reported a median total water volume of approximately 1.1 million gallons. Total w ater

volumes reported in gas disclosures ranged from approximately 91, 00 0 gallons to approximately

7.8 million gallons (5th to 95th percentile) . Total water volumes reported in oil disclosures ranged

from approximately 18, 000 gallons to approximately 6.1 m illion (5th to 95th percentile).

58 FracFocus 1.0 disclosures do not indicate whether a well is vertical or horizontal or the length of the production

interval.Analysis of Data from FracFocus 1.0 March 2015

50 

### Assessed geographically in Table 15

, the median total water volume per disclosure was highest for

Mississippi (nearly 9 .2 million gallons; 4 disclosures) and lowest for Michigan (approximately

33,000 gallons; 15 disclosures). However, Michigan also had the highest 95th percentile value of

any state (more than 15 million gallons), suggesting a wide range of water volumes used within that

state.

At the county level, median total water volumes per disclosure ranged from less than 5,000 gallons

to more than 14 million gallons (Appendix H). Counties that appear ed to have relatively high

median per-disclosure total water volumes are clustered in a few parts of the country :

Pennsylvania, West Virginia, and Ohio; parts of Texas, Oklahoma, and Louisiana; and North Dakota

(Figure 6).

In assessing the range of total water volumes, it is important to consider the median in relation to

the 5th and 95th percentiles, which indicate variability in total water volumes reported in a

particular area. Within-state variability, as measured by the range (5th to 95th percentile) of total

water volumes reported per disclosures in the state, spans three orders of magnitude in some cases Note: Shale basins are those sedimentary basins associated with oil and gas shale plays (US EIA, 2011a). The shale basins off er

basic geologic context for the location of a disclosure; well disclosures likely represent more oil and gas producing formations

than only shale formations. Analysis considered 37,888 disclosures that met selected quality assurance criteria , including:

unique combination of fracture date and API well n umber; fracture date between January 1, 2011

, and February 28, 2013; and

with confirmed state location. Disclosures that did not meet quality assurance criteria were excluded from analysis (642).

Figure 6. Median total water volumes per disclosure , summarized by county

.Analysis of Data from FracFocus 1.0 March 2015

51 

### (Table 15), suggesting a range of operating practices, well lengths, or target formation geolog ies in

an area. Figure 7 shows the geographic distribution of variability in total water volumes as

indicated by the difference between the 5th and 95th percentiles. The figure shows areas of large

variability in total water volumes reported in parts of Colorado , Louisiana, Pennsylvania, and Texas

.



### 3.2.4. Comparing Variability of Total Water Volumes in Selected Counties

Variability in reported total water volumes was examined by selecting and summarizing data on

cumulative and per

- disclosure total water volumes from several counties that represent ed a variety

of geographic settings and were anticipated to represent a variety of fracturing operations

. 59



### Because c umulative total water volumes are strongly influenced by the number of wells in a

location (Section 3.2.2), c ounties with a similar number of disclosures were chosen to minimize one

factor contributing to variability in cumulative total water volumes . The counties chosen for

comparison had 254 to 331 disclosures per county ( around the 90th percentile for number of

59 The comparisons of total water volumes do not attempt to differentiate between vertical and directional or horizontal

wells, because this information was not readily available in the FracFocus 1.0 disclosures. Note: Shale basins are those sedimentary basins associated with oil and gas shale plays (US EIA, 2011a). The shale basins offer

basic geologic context for the location of a disclosure; well disclosures likely represent more oil and gas producing formati ons

than only shale formations. Analysis considered 37,888 disclosures that met selected quality assurance criteria , including:

unique combination of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and

with confirmed state location. Disclosures that did not meet quality assurance criteria were excluded from analysis (642).

Figure 7. Variability in reported total water volumes per disclosure, as measured by the difference between t he

5th and 95th percentiles

.Analysis of Data from FracFocus 1.0 March 2015

52 

### disclosures per county ) to increase the confidence and robustness in the observed results for both

cumulative and per

- disclosure total water volumes . Table 16 su mmarizes total water volume

information from the disclosures for the selected counties.

D ata from the selected counties indicate d a large variability in total water volumes reported for

hydraulic fracturing. C umulative total water volumes for the selected counties ranged from

approximately 9.8 million gallons to almost 1.8 billion gallons. Median per

- disclosure total water

volumes ranged from 16,000 gallons to nearly 6 .3 million gallons. The lowest and highest values for

median total water volumes were bot h within Texas (Milam and Wheeler counties , respectively).

Disclosures from counties in which gas production was predominant (>80% of disclosures)

appear ed to have greater cumulative and median per

- disclosure total water volumes than

disclosures from coun ties in which oil production was predominant (Table 16). Of the nine counties

in Table 16 with the greatest per

- disclosure and cumulative total water volumes, seven were

predominantly gas

- producing, and two had slightly more gas production than oil product ion

(between 60 % and 80% of disclosures). The median total water volume for the nine counties was

1.7 to 3.1 times larger than the greatest median per

- disclosure total water volume reported for a

predominantly oil

- producing county (approximately 2.0 millio n gallons for Dunn County, North

Dakota).

Conversely, eight of the 10 counties in Table 16 with the lowest per

- disclosure and cumulative total

water volumes were predominantly oil

- producing. The data suggest that total water volumes were

generally lower in counties where oil production was predominant. The observed difference in total

water volume by production type may be due to a number of factors, including well depths, the

length of the fractured segment of the well, the formation types that are represe nted, and other

aspects of the fracturing design (Nicot and Scanlon, 2012).

The majority of the counties in Table 16 are located in Texas, providing an opportunity for within

state comparisons of total water volumes. Texas, generally speaking, is a region with a mature oil

and gas industry, a variety of geologic settings, and both conventional and unconventional

production. Total water volumes for the counties in Texas appeared to vary, in part, according to

the predominant production type and geologic sett ing. 60 

### For example, median per

- disclosure total

water volumes in Denton, Wise, and Johnson counties (99% to 100% natural gas production),

located in the Fort Worth Basin in central Texas, ranged from approximately 1.8 to nearly 4.0

million gallons. This is two t o four times greater than the median per

- disclosure total water

volumes reported for disclosures in Howard and Irion counties (about 900,000 gallons each), which

were predominantly oil

- producing and located in the Permian Basin in western Texas. However,

t here is also considerable variability within the Permian Basin: median per

- disclosure total water

volumes from disclosures in Mitchell and Gaines counties (approximately 30,000 and 79,000

gallons, respectively) ranged from 11 to almost 30 times lower than Howard and Irion counties.

60 The counties were grouped by geologic basi n, and the EPA assumed that counties within the same basin may have

similar influences on operations due to comparable geology, geography, infrastructure, and policies.Analysis of Data from FracFocus 1.0 March 2015

53 Table 16. Total w ater volumes for selected counties in approximately the 90th percentile of disclosures

.

State County Number of

disclosures Percent oil

disclosures Percent gas

disclosures Cumulative

total water

volume

(gallons) 

### Total w ater volume per disclosure (gallons)

Median 5th percentile 95th percentile

Texas Wheeler 283 35 % 65% 1,77 4

, 000

, 000 6,292,608 879,360 12,398,544

Arkansas White 309 0.00% 100% 1,749,00 0

, 000 5,782,854 3,655,427 7,416,763

Arkansas Conway 302 0.00% 100% 1,596, 000

, 000 5,266,774 2,919,365 7,957,921

Pennsylvania Susquehanna 327 0.00% 100 % 1,546, 000

, 000 4,798,290 940,909 7,816,150

Arkansas Cleburne 263 0.00% 100% 1,489, 000

, 000 5,974,108 3,401,011 7,538,336

Texas Johnson 289 0.00% 100 % 1,19 1

, 000

, 000 3,969,422 1,754,012 7,202,405

Texas Wise 291 0.34% 100% 1,157, 000

, 000 3,875,046 918,692 7,969,196

Pennsylvania Tioga 286 0.00% 100% 1,13 3

, 000

, 000 3,598,474 2,285,636 6,572,202

Texas DeWitt 320 28% 72 % 1,104, 00 0, 000 3,426,088 2,028,110 4,790,741

Texas Irion 284 99% 0.70% 945, 600

, 000 895,468 45,494 11,729,639

Texas Denton 263 0.76% 99 % 934,7 00

, 000 1,836,744 1,014,405 9,008,399

North Dakota Dunn 331 100% 0.00% 630, 100

, 000 2,017,621 409,803 3,361,183

Texas Reeves 263 100% 0.38% 352,6 00

, 000 1,081,442 104,447 3,865,365

New Mexico Lea 286 98% 1.7% 244, 300

, 000 183,645 53,235 3,730,169

Texas Howard 286 100% 0.00% 219,5 00

, 000 895,986 26,018 1,523,373

Wyoming Sweetwater 321 1.6% 98 % 84,850, 000 229,974 79,090 435,011

Texas Gaines 298 100% 0.00% 44,0 90 ,00 0 79,411 18,330 269,241

Texas Mitchell 278 100% 0.36% 22,0 20

, 000 30,402 14,154 88,003

Texas Milam 254 100 % 0.00% 9,844, 000 16,000 16,000 18,900

All 90 th Percentile Counties 5,534 45% 55% 16,2 30

, 000

, 000 2,503,683 16,000 7,471,633

Entire Dataset 37,796 52% 48% 91,8 10

, 000

, 000 1,508,724 29,526 7,196,702

Note : Analysis considered 37,796 disclosures that met selected quality assurance criteria , including : unique combination of fracture date and API well number; fracture date

between January 1, 2011, and February 28, 2013; and criteria for water volumes. Disclosures that did not meet quality assurance criteria were excl uded from analysis (734

disclosures).Analysis of Data from FracFocus 1.0 March 2015

54 

### Wh en comparing t he r anges ( 5 th to 95 th percentile ) of per-disclosure total water volumes r eported

for each county, those reported in Mitchell, Gaines, and Milam counties (100% oil

disclosures) appeared to be smaller than those reported in Wheeler, Johnson, Wise, DeWitt, and

Denton co unties ( 65% to 100% gas d isclosures).

Within the Texas counties in Table 16, the range of total water volumes reported per disclosure (as

represented by the 5th and 95th percentiles) differed by as much as 11 million gallons, as observed

in Irion County, and as little as 2,900 gallons (Milam County). The large amount of variability in

some counties suggests that wells located within a relatively short surface distance of each other

used different volumes of water for hydraulic fracturing

. Use of non-aqueous ingredients, such as

gases or hydrocarbons, in base fluids, which could decrease the total volume of water needed in

fracturing fluids, did not appear to contribute appreciably to the variability in counties in Texas;

liquid nitrogen was reported in 59 disclosures in Mitchell County and 10 disclosures in Howard

County.

A wide range of reported total water volumes within a county may be a result of hydraulic

fracturing in multiple formations within the county and the influence of specific formation

conditions on operations. The TVD of wells in Irion and Milam counties was assessed as an

indicator of the number of formations that may be hydraulically fractured in the area. 61 

### A relatively

small range of depths might indicate that one formation was being developed for production,

whereas clusters of ranges or a broad range of depths might indicate concurrent development in

multiple formations in an area. The TVDs in Milam County disclosures were generally shallower

than Irion County disclosures, with 99% of disclosures in Milam County ranging from 650 to 998

feet (median 940 feet) below surface. 62 

### In Irion County, TVDs were deeper and ranged (minimum to

maximum) from 3,766 to 9,184 feet (median 7,038 feet) below surface. The relatively narrow range

of TVDs reported in disclosures from Milam County, in combination with the relatively narrow

range of per-disclosure total water volumes reported in Table 16, suggest that a single formation is

represented by the disclosures for Milam County in the project database. Additional information on

producing formations in Milam County would be needed to verify this observation.



### 3.2.5. Water Sources

Although FracFocus 1.0 disclosures do not have a specific data field for identifying water sources,

some operators used terminology in their submissions that indicated the source or quality of water

used for base fluids. Twenty-nine percent of disclosures (10,301 of 36,046 disclosures) included

information related to water sources, though rates of reporting varied by state (Table 17). Some of

these terms indicated a condition of water quality, such as “fresh

, ” rather than a specific

identification of the source of the water (e.g., ground water, surface water). Twenty-three different

source water-related terms and combinations of terms were identified in the project database

,

61 A relationship between TVD and water volumes was not apparent for the entire dataset.

62 The range (minimum to maximum) of depths reported on the 254 disclosures from Milam County, Texas, were below

the 5th percentile of TVD values found in the project database. Two hundred ninety-eight disclosures in the project

database indicated a TVD less than 1,000 f ee t in depth. For the project database, the 5th percentile for TVD was 2,872 feet

below surface, the 95th percentile was 12,796 feet, and the median was 8,140 feet.Analysis of Data from FracFocus 1.0 March 2015

55 Table 17. Number of disclosures having terms suggestive of water sources, summarized by state.

Reported water source Number of disclosures

AK AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT WV WY State

Uncertain * Total

Fresh

Fresh 6 45 1,042 33 489 6 2 18 503 142 40 914 118 3,020 60 46 543 18 7,045

Lease water 8 1 5 1 20 31 9 75

Surface 40 40

Reused

Produced 8 8 10 75 101

Produced/recycled 31 5 36

Recycled 2 181 1 143 327

Mixed/Other

Brine 3 4 6 15 1 3 2 42 3 1 80

Brine/fresh 3 3 1 1 3 13 1 25

Brine/lease water 1 1

Brine/salt water 2 2

Flowback/salt water 1 1

Fresh/lease water 1 1 2

Fresh/nominal recycled 4 82 2 88

Fresh/produced 1 1

Fresh/produced/ recycled 42 94 37 470 127 76 846

Fresh/recycled 261 25 35 8 1 330

Fresh/salt water 2 2

Fresh/treated water 1 1

Nominal fresh/ recycled 224 224

Recycled/surface 907 907

Salt water 2 18 14 2 63 99

Sea water 11 11

Treated water 36 1 1 19 57

Table continued on next pageAnalysis of Data from FracFocus 1.0 March 2015

56 Reported water source Number of disclosures

AK AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT WV WY State

Uncertain * Total

All water sources

Disclosures with water sources 19 1,305 19 1,551 40 610 6 4 18 509 144 134 1,009 699 3,325 69 130 690 20 10,301

Disclosures in entire dataset 37 1,409 704 4,622 100 1,029 14 4 201 2,073 1,136 147 1,832 2,458 17,056 1,279 273 1,388 139 36,046

Percentage that identify water

source 51% 93% 2.7% 34% 40% 59% 43% 100% 9.0% 25% 13% 91% 55% 28% 19% 5.4% 48% 50% 14% 29%

Water (source unspecified) 17 20 624 2,536 34 308 1 0 83 965 863 11 418 1,121 10,024 1,008 69 595 57 18,809

* State location did not pass state locational quality assurance criteria.

Note : Analysis considered 36,046 dis closures and 925,972 ingredient records that met selected quality assurance criteria , including : completely parsed; unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and valid concentrations. Disclosures that did not meet quality assurance

criteria (2,484) or other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

57 

### reflecting inconsistency and possible redundancy in terminology used. Operators often described

water using general terms, such as “fresh” or “brine,” for which no standard definitions were

provided. Source water analyses are therefore limited to operator

- reported terminology.

The term “fresh” was most often used to describe water used for base fl uids and was listed as the

only term in 68% of disclosures with information on source water (7,045 of 10,301) across 17

states (Table 17). It is not known whether any of these disclosures used the term “fresh” to refer to

recycled fluids that was treated t o achieve the quality of fresh water. Disclosures listing only the

term “fresh” were found in 99% of all disclosures reporting a source of water in North Dakota (503

of 509 disclosures) and 91% of those in Texas (3,020 of 3,325 disclosures). By contrast, t he term

“fresh” was used exclusively in only 3% of disclosures reporting a water source in Arkansas (45 of

1,305). Differences observed among disclosures from different states are likely due, in part, to

variations in the rate of overall reporting of water sources and inconsistencies in terminology used.

After disclosures that reported only use of fresh water, mixtures of more than one source were

most commonly found in the project database. Twenty

- four percent of disclosures (2,466 of 10,301

disclosures; Table 17) that identified a source of water used more than one term, with the most

common combination being “recycled” and “surface” (907 of 10,301 disclosures, all from Arkansas).

As shown in Table 18, when the term “fresh” was used in combination with other source water

types, fresh water tended to make up a larger proportion of the hydraulic fracturing fluid. For

instance, for disclosures in which the term “fresh” was used in comb ination with “recycled” or

“produced,” the median maximum fluid concentration of “fresh” water in hydraulic fracturing fluid

ranged from 79 % to 90% by mass. The median maximum fluid concentrations associated with

“recycled” or “produced” water, when used w ith “fresh” water, ranged from 4 % to 90% by mass.

Given inconsistencies in the use of terms associated with recycling of water, the frequenc y of use of

recycled water was not clear from this analysis. Reporting of the terms “flowback,” “recycled,” or

“pro duced” in disclosures could indicate that recycling of flowback or produced water occurred.

Table 17 shows that the terms “flowback,” “recycled,” and “produced,” either alone or in

combination with other water source terms, were included in 28% of disclosu res containing water

source information (2,861 of 10,301 disclosures). Disclosures in several states indicated the use of

brine, which may also represent the use of flowback or produced water. Disclosures that contained

only the terms “recycled” or “produc ed” (either alone or together) occurred in Arkansas, California,

Colorado, Oklahoma, Pennsylvania, Texas, and Wyoming. For these states, the median maximum

fluid concentrations for “recycled” and “produced” were generally in excess of 70% by mass,

suggesti ng substantial use of some quantity of produced water in base fluids for some disclosures.

Of the disclosures that included information on water sources, the greatest number of disclosures

indicating the use of “recycled” or “produced” water, either alone or in combination with other

water sources, was found in disclosures from Arkansas (93% or 1,220 of 1,305 disclosures). Median

maximum fluid concentrations of “recycled” or “ produced ” water ranged from 10 % to 93%

depending on whether these water sources we re blended with other sources. These concentrationsAnalysis of Data from FracFocus 1.0 March 2015

58 Table 18. Median maximum fluid concentrations of water by source , summarized by state.

Reported

water source Number of disclosures

AK AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT WV WY State

U ncertain * Entire

dataset

Fresh

Fresh 84 92 81 94 87 91 88 87 86 85 84 90 83 87 91 86 82 87 87

Lease water 77 95 89 84 94 86 40 86

Surfac e 92 92

Reused

Produced 25 72 93 86 85

Produc ed/

recycled 94/94 90/90 94/94

Recycl ed 93 100 54 93 98

Mixed

Brine 71 83 91 88 95 84 92 83 87 87 86

Brine/ fresh 13/69 7/84 4/85 3/86 3/93 13/77 5/82 13/78

Brine/ lease

water 6/86 6/86

Brine/ salt water 2/90 2/90

Flowba ck/salt

water 27/27 27/27

Fresh/ lease

water 53/41 94/94 74/68

Fresh/ nominal

recycled 81 88 90 88

Fresh/ produced 87/4 87/4

Fresh/produced/

recycled 80/10/10 76/8/8 85/2/2 71/15/15 85/3/3 77/8/8 76/10/10

Fresh/recycled 79/13 81/81 90/90 90/90 84/84 81/16

Fresh/salt water 51/36 51/36

Fresh/ treated

water 81/81 81/81

Table continued on next pageAnalysis of Data from FracFocus 1.0 March 2015

59 Reported

water source Number of disclosures

AK AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT WV WY State

U ncertain * Entire

dataset

Nominal fresh/

recycled 100 100

Recycled/surface 29/62 29/62

Salt water 100 91 87 81 94 92

Sea wa ter 81 81

Treate d water 93 89 95 85 93

All water sources

Median (source

specified) 82 47 74 84 94 87 91 88 87 86 85 14 90 26 87 90 23 85 87 83

Median (source

unspecified) 99 91 78 91 92 90 92 87 86 80 89 92 88 88 89 90 80 87 88

* State location did not pass state locational quality assurance criteria.

Note : Analysis considered 36,046 disclosures and 925,972 ingredient record s that met selected quality assurance criteria , including : completely parsed; unique combination of

fractu re date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and valid concentrations. Disclosures that did not meet quality assurance

criteria (2,484) or other, query

- specific criteria were excluded from analysis

.Analysis of Data from FracFocus 1.0 March 2015

60 

### suggest substantial use of recycled water during some hydraulic fracturing operations. Notable use

of recycled and produced water was also indicate d in Pennsylvania (83% of disclosures with source

water terms), Ohio (70%), and West Virginia (65%), although the total numbers of disclosures

were much lower in Ohio and West Virginia than in Arkansas and Pennsylvania.



## Proppants

Proppants, or materials th at frequently functioned as proppants, were often reported in the

ingredients table. The proppant analyses in this section included 26,935 unique disclosures in the

project database with fracture dates between January 1, 2011, and February 28, 2013. Proppa nts

were identified through entries in the purpose field (i.e., an entry similar to proppant, sand, quartz,

or silica). The strategy of identifying proppants using the purpose field was conservative but

consistent with the study’s approach of reporting dat a as closely as possible to the original PDF

disclosures. Because some operators listed proppant ingredients without providing an entry in the

purpose field, this analysis provides a lower limit on information regarding proppant use. 63



### Ingredients associated with resin coatings on proppants were excluded from this analysis and

instead included in the additive ingredient analyses described in Section 3.3.

T he median maximum concentration of proppant ingredients in hydraulic fracturing f luids was

11% by mass, with a range of 2.4 % to 24% by mass (5th to 95th percentile ) . Table 19 lists the

ingredients most frequently reported as proppants in the project database and shows the maximum

concentrations of the ingredients in hydraulic fracturin g fluids and in additives. The 10 ingredients

in the table represent over 99% of disclosures that have ingredients with proppant

- related

purposes in the project database

.

Quartz was the most prevalent proppant ingredient reported and was identified in 98% of all

disclosures that identified proppants by purpose, with a median maximum fluid concentration of

10% by mass (Table 19). Silicate minerals, most notably quartz, are commonly used as proppants

due to their mechanical strength and availability in large quantities (Beckwith, 2011). Other

minerals identified as proppants in the project database include mullite, corundum, calcined

bauxite, bauxite, titanium dioxide, ferric oxide, and alumina, as well as other less frequently

reported minerals not present i n Table 19. Proppants also have been manufactured from other

materials

, including glass, fly ash, and metallurgical slags (Beckwith, 2011), which were not

observed in the project database.

For almost 90% of the disclosures represented in the proppant anal ysis, quartz was the only

ingredient listed. Other proppant ingredients were reported in many fewer disclosures than quartz,

and they had lower median maximum fluid concentrations (Table 19) , indicating their usage in

mixtures that may be designed to achie ve a certain strength or densit y

, which suggests that they

may be part of proppant mixture s or may be incorporated into the proppant at different stages of a

63 A broader screening of multiple fields for proppant

- related terms suggeste d the number of disclosures that included

information on proppant use likely exceeded 34,000. This analysis queried for unique disclosures that met the date

criterion with “sand” in the trade name, purpose, or comments fields; “prop” in the purpose field; or a chemical name of

“sand” or “quartz” with a valid maximum fluid concentration greater than 5% by mass

.Analysis of Data from FracFocus 1.0 March 2015

61 Table 19. Ten most frequently reported proppant ingredients, ranked by frequency of occurrence

.

EPA

- standardized

chemical name CASRN Maximum concentration in

hydraulic fracturing fluid (% by mass) Maximum concentration in

additive (% by mass)

Number ( % ) of

d isclosures Median 5 th

percentile 95 th

percentile Number ( % ) of

ingredient

record s Median 5 th

percentile 95 th

percentile

Quartz 14808

- 60

- 7 26,273 (98%) 10 2.4 24 40,337 (80%) 100 97 100

Mullite 1302

- 93

- 8 1,352 (5.0%) 3.4 0.000000 * 12 1,592 (3.2%) 85 20 100

Cristobalite 14464

- 46

- 1 1,048 (3.9%) 0.80 0.000000 * 3.9 1,201 (2.4%) 30 5.0 30

Silica, amorphous 7631

- 86

- 9 946 (3.5%) 1.1 0.000000 * 3.9 1,048 (2.1%) 30 10 35

Ferric oxide 1309

- 37

- 1 867 (3.2%) 0.012 0.00038 0.66 1,406 (2.8%) 0.10 0.10 10

Alumina 1344

- 28

- 1 793 (2.9%) 0.14 0.050 16 1,347 (2.7%) 1.1 0.80 100

Titanium dioxide 13463

- 67

- 7 711 (2.6%) 0.012 0.0042 0.44 1,244 (2.5%) 0.10 0.10 5.0

Corundum (Aluminum

oxide) 1302

- 74

- 5 668 (2.5%) 3.0 0.000000 * 32 681 (1.4%) 60 35 90

Bauxite 1318

- 16

- 7 198 (0.74%) 3.4 0.52 12 218 (0.43%) 100 58 100

Calcined bauxite 66402

- 68

- 4 197 (0.73%) 2.8 0.022 20 210 (0.42%) 85 2.3 100

* Concentration is less than a millionth of a percentage by mass.

Note : Analysis considered 34,675 disclosures and 676,376 ingredient record s that met selected quality assurance criteria , including : completely parsed; unique

combination of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; valid CASRN ; and valid concentrati ons. Disclosures that

did not meet quality assurance criteria (3,855) or other, query

- specific criteria were excluded from analysis.Analysis of Data from FracFocus 1.0 March 2015

62 

### fracturing job. In 1,093 disclosures, quartz was reported with mullite (sometimes with other

proppant ingredients); mullite is an aluminosilicate material that is a significant component in

lightweight ceramic proppants (Brannon and Pearson, 2008). In 508 disclosures , quartz was

reported in combination with corundum and mullite; corundum offers the benefit of very high

strength and is a suitable component of proppant mixes for deep wells (Brannon and Pearson,

2008). In 301 disclosures, quartz was used with bauxite or calcined bauxite, either as the only two

materials or in combination with other proppant ingredients. Some proppant ingredients, such as

hematite, magnesium iron silicate, and rutile had median maximum fluid concentrations under 1%

by mass, suggesting thei r presence as minor constituents in sand mixtures.

Although ingredients associated with resin coatings were not included in the proppants analysis in

Table 19, information in the project database was analyzed to estimate the use of resin

- coated

proppants. Disclosures with proppant

- related purposes were further queried for indications of the

use of resin

- coated proppants in the trade name, chemical name, purpose, and comments fields. The

fields were searched for use of the word “resin” or a common resin ingr edient (e.g., phenolic resin,

methenamine, and epoxy resin). Entries in these fields show ed that 11,452 disclosures indicate d

the use of a resin

- coated proppant (43% of the 26,935 disclosures containing ingredients with

proppant

- related purposes). 64 

### The largest numbers of disclosures including resin

- coated proppants

were from Colorado (2,116) and Texas ( 5,824), where they represent 55% and 46%, respectively,

of the disclosures containing ingredients with proppant

- related purposes in each state. Sever al

hundred disclosures with resin

- coated proppants were also identified in Oklahoma (597

disclosures, 47% of 1,260 disclosures with proppants in that state), New Mexico (597 disclosures,

62% of 959 disclosures with proppants), and North Dakota (481 disclos ures, 32% of 1,525

disclosures with proppants). These data are lower limits for resin

- coated proppant use, because the

analysis was limited to disclosures that identified a proppant

- related purpose for an ingredient

record.



# 4. Conclusions

The summary statist ics presented in this report reflect the information included in the FracFocus

1.0 disclosures ( i.e., records of hydraulic fracturing events at individual wells ) submitted by well

operators for hydraulic fracturing conducted between January 2011 and Februa ry 2013. The

project database compiled from the disclosures and the accompanying D ata M anagement and

Q uality A ssessment R eport (US EPA, 2015 ) are available at www2.epa.gov/

hfstudy/published

- scientific

- papers.

More than 39,000 PDF disclosures were provide d to the EPA by the GWPC in March 2013

. Information on fracture date, well operator, well identification and location, production type, true

vertical depth, and total water volume were successfully extracted from 38,530 disclosures.

Hydraulic fracturing fl uid composition data were extracted for 37,017 disclosures. Hydraulic

fracturing fluid composition data included trade names of additives, the purpose associated with

e ach additive, and the identity ( i.e., chemical name and CASRN) and maximum concentration of

64 An additional 3,116 disclosures indicate the use of resin

- coated proppants when disclosures are included for which the

operator did not indicated a purpose for the proppants are included in the analysis.Analysis of Data from FracFocus 1.0 March 2015

63 

### each ingredient in an additive and in the overall hydraulic fracturing fluid. Reviews of data quality

were conducted on the project database prior to data analysis to ensure that the results of the

analyses reflected the data contained in the PDF disclosures, while identifying obviously invalid or

incorrect data to exclude from analyses.

Analyses were conducted on unique (i.e., non

- duplicate) disclosures with a fracture date between

January 1, 2011, and February 28, 2013, that met appropriate qual ity assurance criteria for a given

analysis . The disclosures identified well locations in 406 counties in 20 states and were reported by

428 well operators. True vertical depths ranged from approximately 2,900 feet to nearly 13,000

feet (5 th to 95 th percen tile), with a median of just over 8,100 feet. Generally, well locations

represented by the disclosures were clustered in the northeast (mainly in and around

Pennsylvania), the west central portion of the country (from North Dakota and Wyoming through

Texas and Louisiana), and in California. Summary statistics performed on the entire dataset reflect

a greater contribution of data from states that are better represented in the project database than

others

— partly due to the locations of oil and gas

- bearing res ervoirs, different state reporting

requirements, and the success in extracting data from individual PDF disclosures.

Because of the large number of disclosures included in the project database (38,530 disclosures ),

the extensive quality checks conducted on the data, and the design of the analyses, the summary

statistics presented in this report represent the central tendency of measures of chemical and water

use for the disclosures in the project database. Although caution is used in drawing broad national,

state, or local inferences in chemical or water use from the summary statistics presented in this

report, the data provide a valuable two

- year snapshot of the composition of hydraulic fracturing

fluids

.

Ingredients reported in the disclosures were categorized in analyses as either additive ingredients,

base fluid ingredients, or proppant ingredients depending upon entries in the trade name, purpose,

and comments fields as well as the reported maximum ingr edient concentration in the hydraulic

fracturing fluid. Additive ingredients generally included chemicals reported for trade names that

had purposes other than base fluid or proppant. The project database contains 692 unique

ingredients reported for additi ves, base fluids, and proppants. Hydraulic fracturing fluids were

generally found to contain 88% by mass water , 10 % by mass quartz , and <1% by mass additive

ingredients (median maximum hydraulic fracturing fluid concentrations).

Additive Ingredients

. The project database identified the additive ingredients most frequently

reported and their concentrations in both hydraulic fracturing fluids and additives. Although

chemicals claimed as CBI contributed to the incompleteness of the project database, a valid C ASRN

was identified and a standardized chemical name was assigned to 65% of the over 1.2 million

ingredient records in the project database . The median number of unique additive ingredients per

disclosure was 14

, with a range of 4 to 28 additive ingredients ( 5 th to 95 th percentile)

. Additive

ingredients found in more than half of all disclosures analyzed include d methanol (in 71 % of

disclosures), hydrochloric acid (65%), and hydrotreated light petroleum distillates (65%). The sum

of the maximum fl uid concentration for all additive ingredients report ed in a disclosure was less

than 1% by mass of the hydraulic fracturing fluid in approximately 80% of disclosures , and the

median maximum fluid concentration was 0.43 % by mass. Operators designated 11% o f allAnalysis of Data from FracFocus 1.0 March 2015

64 

### ingredient records in the project database as CBI . At least one ingredient was claimed confidential

in over 70% of disclosures.

Some disclosures in this study reflect ed a reporting approach that decoupled trade names from

additive ingredient names an d concentrations , which a llowed operators to disclose chemicals while

protecting CBI. This approach is consistent with suggestions by the SEAB and referred to as the

“systems approach” to reporting (SEAB, 2011 ; 2014 ). The systems approach allowed additive

ingredients to be included in analyses for this project

, while protecting the ingredients from being

connected to trade names. Additive ingredients were claimed as CBI by operators in a portion of the

disclosures reported used in this study that had forma tting consistent with the systems approach.

Base Fluids. Base fluids described in the disclosures include d water, water with non

- aqueous

ingredients (e.g., gases or hydrocarbons ) , and hydrocarbons only . More than 93% of the disclosures

analyzed in the stu dy were inferred to use water as a base fluid with a median maximum fluid

concentration of 88% by mass. Total water volumes rep o rted per disclosure ranged from nearly

30,000 gallons to almost 7.2 million gallons (5 th to 95 th percentile), with a median tota l water

volume per disclosure of approximately 1.5 million gallons. Non

- aqueous constituents (e.g.,

nitrogen, carbon dioxide, and hydrocarbons ) were reported as base fluids or in combination with

water as a base fluid in fewer than 3% of disclosures.

O per ators reported the source(s) of water used for base fluid s

, as suggested by the SEAB (SEAB,

2011)

, in 29% of disclosures (10,301 of 36,046 disclosures), even though the FracFocus 1.0

disclosures did not have a specific data field for identifying water sour ces . The term “fresh” was the

most commonly reported water source

, although this term may reflect a condition of water quality

rather than a source. It could not be determined from the disclosures whether the source of the

fresh water was ground water, som e type of surface water body, produced water treated to “fresh”

quality standards, or purchased from a public water system.

A large proportion of disclosures in several states west of the Mississippi River reported fresh

water use in base fluids. More tha n 90% of disclosures that identified water sources in North

Dakota, Oklahoma, and Texas reported fresh water as the only water source. In contrast, more than

70% of disclosures that identified water sources in Ohio and Pennsylvania identified some amount

o f reused and associated types of water in base fluids. These data indicate that base fluids were

more likely to be made up of some reused or recycled water in several of the eastern states

compared to several western states in the project database.

Possible Differences between Oil and Gas Production

. Data in the project database suggested some

differences in additive ingredients and total water volumes reported for disclosures associated with

oil wells and disclosures associated with gas wells

. Oil d isclosures reported a slightly larger number

of additive ingredients per disclosure and a greater maximum concentrations of some of the more

frequently reported additive ingredients (e.g., methanol and hydrochloric acid). Total w ater

volumes appeared to be greater for gas disclosures: The median per

- disclosure total water volume

reported for gas disclosures was approximately 2.9 million gallons, while the median per

- disclosure

total water volume reported for oil disclosures was approximately 1.1 million gal lons (although the

range of water volumes per disclosure overlapped). Differences may reflect any of a number ofAnalysis of Data from FracFocus 1.0 March 2015

65 

### factors, including geologic properties of the formations being fractured, the well design (e.g.,

horizontal versus vertical wells ), or operator practices.

Limitations to the Analys e s

. Conclusions drawn from the analyses presented in this report reflect

data included in the project database. The content of the project database was influenced by the

data conversion process (i.e., extracting data f rom PDFs into the project database) as well as the

completeness and accuracy of data in the original PDF disclosures.

As identified throughout this report, the completeness and accuracy of the data in the original PDF

disclosures may be affected by many f actors, including state reporting requirements and ingredient

reporting practices. By February 2013, six of the 20 states with data in the project database had

implemented regulations that required well operators to disclose chemicals used in hydraulic

fracturing fluids to FracFocus: Colorado, North Dakota, Oklahoma, Pennsylvania, Texas, and Utah.

Three additional states (Louisiana, Montana, and Ohio) required disclosure to either FracFocus or

the state, and five states (Arkansas, Michigan, Ne w Mexico, West Virginia, and Wyoming) required

reporting to the state

. Because the majority of disclosures in the project data base (58%) were

reported in states without mandatory reporting requirements to FracFocus or had fracture dates

prior to regulatory effective dates for mandatory reporting to FracFocus, the project database

cannot be assumed to be complete.

Designations of CBI , reporting of invalid CASRNs and ingredient concentrations, and the

modification of FracFocus 1.0 disclosure templates by oper ators contributed to an incomplete

record of chemical use in the project database . Furthermore, parsing problems with the modified

templates generated erroneous ingredient records. Additionally, r eporting inconsistencies in

additive purposes, chemical name s, sources of water for base fluid, and identification of base fluid

or proppant in the purpose field prevented a stronger statistical evaluation or interpretation of

results in this project. Despite the challenges to adapting a dataset originally created for local use

and single

- PDF viewing to answer broader questions, the project database provided substantial

insight into water and chemical use for hydraulic fracturing.

FracFocus 2.0, developed in late 2012, provides features such as dropdown menus, warn ing and

error messages during submission, and automatic formatting of certain fields that can enhance the

quality and consistency of data submitted by operators. 65 

### T he FracFocus 2.0 infrastructure was also

updated to store data in XML format rather than PDF

. In early 2015, the GWPC and the IOGCC

announced additional updates to Frac Focus that include providing public extraction of data in a

machine readable format and verification of CASRNs.

Contribution of FracFocus to Scientific Studies. U nderstanding the c hemical composition of hydraulic

fracturing fluids and the water volumes used for hydraulic fracturing is important for assessing or

minimizing potential drinking water impacts related to hydraulic fracturing and for planning to

avoid those potential impac ts. The wide diversity of additive ingredients and total water volumes

reported in disclosures submitted to FracFocus 1.0 emphasizes the importance of analyzing

hydraulic fracturing practices at different scales (from local to state to regional) as well as by

65 Although FracFocus 2.0 became an option for submitting information in late 2012, it was not the exclusive disclosure

mechanism until June 2013.Analysis of Data from FracFocus 1.0 March 2015

66 

### production type. The project database and the summary statistics presented in this report could

serve as a general re ference, as well as a local or regional resource, for a variety of stakeholders,

including tribal, state, and local governments; academic researchers; the oil and gas industry; non

governmental organizations; and the public

.Analysis of Data from FracFocus 1.0 March 2015

67 

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### Gupta, DVS, Pierce, RG, and Lift, ND. 1997. Non

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### Drilling and High

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71 

# Glossary

Acid An acid is a chemical that reduces the pH of an aqueous solution by

increasing the ratio of hydronium (H 3 

### O + 

### ) ions to hydroxide (OH

- 

### ) ions

in solution. In hydraulic fracturing, acids such as hydrochloric,

hydrofluoric, acetic, formic and fluoroboric are used alone or as

blends to achieve greater fracture penetration and to reduce clogging

of the pore spaces and fractures by dissolving minerals and clays.

Additive A n ingredient or combination of ingredients that is added to a

hydraulic fracturing base fluid to serve a specific purpose. Additives

improve the efficiency and effectiveness of a hydraulic fracturing job

by, for example, limiting the growth of bacteria and preventing

corrosion of the well casing. Additives and their purposes are defined

within the context of hydraulic fracturing

, although some additives

may also be used for other activities than hydraulic fracturing. In this

report, an additive corresponds to the entry in the “trade name” field

of a disclosure.

Addit ive ingredient For the purpose of this report, generally the ingredients in additive s

with purpose s other than those associated with base fluids or

proppants , but also includes non

- aqueous base fluid ingredients and

resin coatings for proppants

.

API well number A unique identifying number assigned using a system developed by

the American Petroleum Institute (API). The system applies to oil and

gas wells drilled in the United States.

Base A base is a chemical that increases the pH of an aqueous solution by

increasing the ratio of hydroxide (OH

- 

### ) ions to hydronium (H 3 

### O + 

### ) ions

in solution. In hydraulic fracturing, bases help control the pH of

fracturing fluids and optimize their performance.

Base fluid The fluid into which additives and proppant s are mixed t o formulate

a hydraulic fracturing fluid s

.

Basin A depression in the crust of the Earth formed by plate tectonic

activity. Sediments may accumulate in the basin after the depression

is created, or they may be deposited before tectonic activity forms the

basin.

Biocide An additive that can be used to co ntrol bacterial growth, which can

affect the viscosity of the fracturing fluid or reduce permeability in

the formation. Common problematic bacteria include sulfate

-Analysis of Data from FracFocus 1.0 March 2015

72 

### reducing bacteria, slime

- forming bacteria, iron

- oxidizing bacteria,

and bacteria that attack polymers in fracturing fluids.

Breaker Also referred to as a gel breaker, an additive used to reduce the

viscosity of a gelled fracturing fluid. This is accomplished by breaking

long

- chain polymer molecules into shorter segments. Use of a breaker

facilitates flowback of the fluid after fracturing.

Buffer A buffer allows an aqueous solution to resist changes in pH. It

consists of water, a weak acid or weak base, and a salt of the weak

acid or weak base. Buffers are used to optimize performance of

f racturing fluids that use complex polymers or crosslinked gelling

agents.

CASRN Chemical Abstract s Service Registry Number (CASRN). A unique

numeric identifier assigned by the Chemical Abstracts Service for a

single substance. The substance can be composed of a single chemical

(e.g., methanol) or can be a mixture of chemicals (e.g., hydrotreated

light petroleum distillates).

CBI Confidential Business Information. Information that contains trade

secrets, commercial or financial information, or other information

that has been claimed as confidential by the submitter.

Clay control An additive used in hydraulic fracturing to prevent swelling and

migration of formation clays when water

- based fluids are used.

Swelling and migration of clays can cause reduced permeability and

productivity by clogging pore spaces in the formation.

Conv entional production Crude oil and natural gas that is produced by a well drilled into a

geologic formation in which the reservoir and fluid characteristics

permit oil and natural gas to readily flow to the wellbore.

Corrosion inhibitor An additive used to protect iron and steel equipment and wellbore

components from corrosive ingredients used in acid treatments.

These corrosive agents include various types of acids and hydrogen

sulfide.

Crosslinker An additive, typically a metallic sal t, added to a linear gel base fluid to

create a more viscous gel. This enables a fracturing fluid to carry

more proppant. Crosslinkers increase the viscosity of the linear gel

fluid by connecting polymer molecules in a three dimensional

structure. After fr acturing, the viscosity is reduced by a breaker to

facilitate flowback of the fluid to the well.Analysis of Data from FracFocus 1.0 March 2015

73 

### CSV Comma

- separated values (CSV). File format where tabular data are

presented as plain text with values separated by a special character,

commonly a comma (,).

Disclosure As used in this report, a disclosure refers to all data submitted for a

specific oil and gas production well for a specific fracture date

.

Flowback After the hydraulic fracturing procedure is completed and pressure is

released, the direction of fluid flow reverses, and fracturing fluids,

any fluids naturally found in the formation, and excess proppant flow

up through the wellbore to the surface. The fluids that return to the

surface are commonly referred to as flowback. Flowback also refers

to the process of allowing these fluids to flow from the well following

a treatment.

Formation A continuous body of rock with distinctive properties and large

enough dimensions for mapping.

Friction reducer An additive used to reduce friction in the wellbore, allowing fluid to

move more quickly and efficiently.

Gelling agent An additive used to increase fluid viscosity. Gels may be linear or

cross

- linked. The greater viscosity serves several purposes, inclu ding

increasing the ability of the fluid to carry proppant and helping to

minimize fluid loss.

Geoprocessing tool Tool available in ArcGIS that is used to analyze and process spatial

data.

Hydraulic f

racturing

fluid A mixture of base fluid, additive ingredients , and proppants pumped

under high pressure into a well to create fractures in the target

formation and to carry proppant into the fractures

.

Iron control agent An additive used to increase the solubility of iron, removing and

preventing the precipitation of iron

- bearing additives such as iron

hydroxide and iron sulfide. This helps control rust, sludges, and scale

that can damage the formation.

Non

- emulsifier A chemical or mixture of chemicals used to prevent or minimize the

formation of emulsions. Emulsions may form from the interaction of

the fracturing fluid with hydrocarbons in the subsurface. A non

emulsifier facilitates separation of oil or gas from the flo wback.

Parsing Process of analyzing a string of symbols to identify and separate

various components.Analysis of Data from FracFocus 1.0 March 2015

74 

### pH control An additive that either adjusts the pH of the fluid or buffers the pH

against change (buffer). Control of pH is needed for effective

performance of the fracturing fluid, including facilitating the

crosslinking of gels and use of breakers.

Play An area in which hydrocarbon accumulations occur. The

accumulations typically have similar geologic, geographic, and

temporal properties such as source rock, hydrocarbon type,

migration pathway, and trapping mechanism.

Proppant Solids of a particular size, shape, and material that are carried into

the fractures in a hydrocarbon formation by the hydraulic fracturing

fluid. Their purpose is to hold the fractures open after hydraulic

fracturing. In addition to naturally occurring sand, engineered

material s, such as resin

- coated sand or high

- strength ceramic

materials (e.g., sintered bauxite) may also be used.

Reservoir Generally, a subsurface body of rock able to store fluids such as oil

and natural gas and allow the flow of fluids within the rock.

Scale inhibitor An additive used to control or prevent the formation of mineral scales

in the formation or the well tubing. Scale deposition can inhibit

hydrocarbon flow.

Stacked plays Multiple reservoirs located at different depths within a sedimentary

basin . Stacked plays may be accessed using a single vertical well or

multiple horizontal wells, and may be either conventional or

unconventional.

Surfactant A chemical with polar and non

- polar regions that allow it to reduce

the surface tension at the interface between two liquids or between a

liquid and a solid. This property means that surfactants can be used

as emulsifiers, foaming agents, defoaming agents, and dispersants.

True vertical depth

(TVD) The vertical distance from a subsurface point in t he well to a point at

the surface, usually the rotary kelly bushing.

Unconventional

production Oil and natural gas that cannot be produced by the methods that are

typically used for permeable sandstone and carbonate hydrocarbon

reservoirs. Reservoirs that require unconventional production have

porosities, permeabilities, or other properties that nec essitate

techniques such as hydraulic fracturing to stimulate the flow of

hydrocarbons to a well. Unconventional production may occur in

hydrocarbon reservoirs including coalbeds, shales, and sandstones.Analysis of Data from FracFocus 1.0 March 2015

75 

### Viscosifier An additive used to increase the visco sity of a fluid. Viscosity is a fluid

property that indicates the fluid’s resistance to flow.

Well operator A company that owns and/or operates oil and gas wells.

Wellbore The drilled hole in which the well is constructed including the

openhole or uncased portion of the well. The term “wellbore” is

independent of the materials that form the well such as casing and

tubing.

XML file A file coded according to the Extensible Markup Language (XML) for

easy sharing of data and formatting.



## References

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- permian

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Schlumberger. 2014. Schlumberger Oilfield Glossary. Available at

http://www. glossary.oilfield.slb.com. Accessed January 22, 2014.

Society of Petroleum Engineers. 2014. PetroWiki Glossary. Available at http://petrowiki.org/

Category:Glossary. Accessed January 22, 2014.

US E nergy I nformation A dministration . 2014. Glossary. Available at http://www.eia.gov/

tools/glossary/. Accessed April 28, 2014.

US G eological S urvey . 2014. Geologic Glossary. Available at http://geomaps.wr.usgs.gov/parks/

misc/glossarya.html. Accessed January 22, 2014.Analysis of Data from FracFocus 1.0 March 2015



# Appendix A. Shale Basin Map

Note: Shale basins are those sedimentary basins associated with oil and gas shale plays (US EIA, 2011a). The EIA

- delineated

shale basins provide basic geologic context for the locations of disclosures in the project database . Disclosures also represent oil

and gas wells producing from tight sand plays and coalbed methane plays; maps of tight gas basins and coalbed methane basins

are available from the U. S. E nergy I nformation A dministration . The shale gas basins are presented here because they represent

many major sedimentary basins in the United States.

Figure A

- 1. Shale basins map (US EIA, 2011a)

.

76Analysis of Data from FracFocus 1.0 March 2015



# Appendix B. Chemical Families for Ingredients Listed as

Confidential Business Information

This appendix includes a tabulation of information provided by well operators on the chemical

families of the ingredients that were claimed to be confidential business information (CBI). We

evaluated 122,915 ingredient re cords (from disclosures with unique combina tions of fracture date

and API well n umber and with a fracture date between January 1, 2011

, and February 28, 2013)

that have a CBI synonym in the CASRN field and an entry in the chemical name field. 1 

### An additiona l

696 ingredient records had a CBI entry in the CASRN field

, but no information in the chemical name

field.

Ingredient records containing “ CBI ” or a synonym in the CASRN field were sorted into the

categories listed in the table below. Entries in the recor ds were minimally standardized to correct

for misspellings and capitalization and to consolidate nearly identical entries. Those entries with

partially defined chemical information were tabulated to list the number and percentage of

disclosures associated with each of the standardized chemical families listed in Table B

- 1

. The

partial definition provided enough description to narrow the scope of potential chemicals or

indicate a general chemical group.

Type of entry in the chemical name field Percentage of

ingredient records

CBI synonym 9.6%

Partially defined chemical (enough description to narrow the list of

potential chemicals or indicate a general chemical group) 79%

Ingredient ( specifically defined chemical) (e.g., hydrochloric acid,

ammonium chloride, amorphous silica) 2.1%

Purpose (entries provides information on purpose rather than

chemical family) (e.g., surfactant) 7.5%

Multiple entries (more than one chemical name in the field) 0.088%

Other (an entry that does not provide information on a specific

chemical or chemical grouping and does not fall into one of the other

categories) 1.3%

Total 100%

1 The 122,915 ingredient records are a subset of the 129,311 ingredient records identified as CBI ingredient records in

Section 2.2.3. The 129,311 ingredient records were identified by the presence of “CBI” or a synonym in either the CASRN

field or chemical name field. The 122,915 ingredient records have “CBI” or a synonym in the CASRN field and a non

- null

entry in the chemical name field.

77Analysis of Data from FracFocus 1.0 March 2015

Table B

- 1. Chemical families for CBI ingredient records.

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Oxyalkylated alcohol 12 5,809 4.7%

Petroleum distillates 23 4,974 4.0%

Quaternary ammonium

compounds 27 4,461 3.6%

Aromatic aldehyde 9 2,227 1.8%

Polyoxyalkylenes 6 1,955 1.6%

Olefins 9 1,933 1.6%

Fatty acids 4 1,920 1.6%

Aliphatic acids 3 1,748 1.4%

Cured acrylic resin 9 1,701 1.4%

Polyglycol ester 4 1,697 1.4%

Polyol ester 3 1,695 1.4%

Aliphatic alcohols, ethoxylated

#1 3 1,627 1.3%

Vinyl copolymer 3 1,600 1. 3 %

Amino alkyl phosphonic acid 4 1,530 1.2%

Alcohol ethoxylate surfactants 6 1,528 1.2%

Aliphatic hydrocarbon 3 1,527 1.2%

Carbohydrate polymer 2 1,439 1.2%

Alkylene oxide block polymer 6 1,412 1.1%

Copolymer 2 1,390 1.1%

Organic amine resin salt 5 1,304 1.1%

Oxyalkylated alkyl alcohol 6 1,257 1.0%

Aliphatic polyol 2 1,073 0.87%

Phosphonate salt 6 1,044 0.85%

Organic sulfur compounds 8 1,029 0.84%

Oxyalkylated fatty acid 5 984 0.80%

Ethoxylated alcohol blend 2 971 0.79%

Polymer 9 968 0.79%

Quaternary amines 10 927 0.75%

Inorganic salt 7 917 0.75%

Alkoxylated amines 6 882 0.72%

Aliphatic alcohol glycol ether 3 876 0.71%

Haloalkyl heteropolycycle salt 8 858 0.70%

Ethoxylated alcohol 5 855 0.70%

Alcohols 6 841 0.68%

Borate salt 12 810 0.66%

Table continued on next page

78Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Amine salt 9 802 0.65%

Alcohol ethoxylate 9 794 0. 65 %

Polyquaternary amine 3 781 0. 64 %

Alcohol alkoxylate 5 766 0. 62 %

Aldehyde 7 754 0.61%

Organic phosphonate 5 747 0. 61 %

Inorganic chemical 3 737 0.60%

Polyelectrolyte 4 737 0.60%

n

- olefins 5 711 0.58%

Oxyalkylated phenolic resin 8 708 0.58%

Guar gum derivative 6 696 0.57%

Branched alcohol oxyalkylate 1 653 0.53%

Cocoamido tertiary amine 2 607 0.49%

Sulfonate 7 568 0.46%

Cyclic alkanes 2 546 0.44%

Ethoxylated alcohols 4 493 0.40%

Ammonium salt 10 491 0.40%

Hydrocarbon 3 477 0.39%

Quaternary ammonium salt 8 463 0.38%

Glycol ether 4 458 0.37%

Amine phosphonate 1 2 424 0.34%

Carbohydrates 5 415 0.34%

Essential oils 3 414 0.34%

Alkyl phosphate ester 3 412 0.34%

Fatty acid amidoalkyl betaine 1 412 0.34%

Clay 6 406 0.33%

Sulfonated polystyrene 1 405 0.33%

Polyethoxylated alkanol ( 1 ) 1 404 0.33%

Polyethoxylated alkanol ( 2 ) 1 404 0.33%

Polyacrylamide copolymer 5 393 0.32%

Acrylamide 2 380 0.31%

Organophilic clays 7 369 0.30%

Substituted alcohol 2 369 0.30%

Ethoxylated nonylphenol 8 340 0.28%

Acid phosphate ester 2 337 0.27%

Alkyl alkoxylate 3 335 0.27%

Polyacrylate 7 329 0.27%

Ethoxylated fatty acid 4 327 0.27%

Table continued on next page

79Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Aliphatic alcohol 2 306 0.25%

Organic polyol 3 304 0.25%

Castor oil 3 303 0.25%

Fatty acid 1 303 0.25%

Fatty acid salt 1 303 0.25%

Polysaccharide blend 2 299 0.24%

Polysubstituted aromatic

hydrocarbon solvent 1 286 0.23%

Synthetic organic polymer 2 281 0.23%

Oxyalkylated alkanols 2 280 0.23%

Neutralized polymer 2 278 0.23%

Non

- hazardous salts (Choline) 2 276 0.22%

Nonylphenol ethoxylate 6 275 0.22%

Ethoxylated alcohols 2 2 267 0.22%

Cationic water soluble polymer

emulsion 2 266 0.22%

Organic sulfonic acid salt 2 265 0.22%

Oxyalkylated polyamine 2 264 0.21%

Synthetic polymer 3 256 0.21%

Quaternary salt 2 252 0.21%

Anionic copolymer 2 248 0.20%

Polyglycol 1 245 0.20%

Anionic polyacrylamide 2 242 0.20%

Acrylamide modified polymer 3 241 0.20%

Neutralized polycarboxylic acid 2 234 0.19%

Fatty acids, tall oil 5 231 0.19%

Amine phosphonate 5 1 228 0.19%

Non

- hazardous salts 5 226 0.18%

Amine derivative 2 220 0.18%

Hemicellulase enzyme

concentrate 1 219 0.18%

Secondary alcohol 4 218 0.18%

Mannanase enzymes 6 215 0.17%

Neutralized traceable polymer 1 214 0.17%

Cationic polyacrylamide

copolymer 8 209 0.17%

Enzyme 7 207 0.17%

Organic alcohol 1 199 0.16%

Proprietary methanol 1 199 0.16%

Table continued on next page

80Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

1,3

- propanediol, 2

- amino

2(hm)

- polymer 2 192 0.16%

Polyacrylamide polymer 1 192 0.16%

Polyoxyalkylenes surfactant 1 192 0.16%

Anionic polymer 4 185 0.15%

Inorganic base 2 177 0.14%

Ammonium alkyl ether sulfate 1 175 0.14%

Anionic polyacrylamide

copolymer 3 173 0.14%

Enzyme solution 1 170 0.14%

Amine phosphonate 5,

potassium salt 2 169 0.14%

Substituted alkylamine 1 162 0.13%

Olefin sulfonate 2 160 0.13%

Polyester 1 158 0.13%

Hexyl alcohol, ethyxylated 1 157 0.13%

Alkyl alcohol 1 152 0. 12 %

Hydrotreated light petroleum

distillate 4 146 0.12%

Acyclic hydrocarbons 4 145 0.12%

Oxylated alkanols 1 145 0.12%

Acrylate polymer 5 144 0.12%

Light aromatic hydrocarbon

solvent 1 144 0.12%

Acrylamide polymer 3 143 0.12%

Cellulase enzyme 3 143 0.12%

Phosphonic acid 3 140 0. 11 %

Alkanolamine/aldehyde

condensate 1 134 0.11%

Ethoxylated phenolic resin 1 128 0. 10 %

Amines 2 127 0.10%

Oxyalkylated alkylphenol 3 127 0.10%

Salt 4 127 0.10%

Modified carboxylic acid

polymer salt 2 123 0.10%

Sodium salt 3 122 0.10%

Acetylenic alcohol 2 121 0.10%

Complex alkylaryl polyo

- ester 2 121 0.10%

Phosphoric acid ester 3 120 0.10%

Organic phosphonic acid salts 6 119 0.10%

Table continued on next page

81Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Unsulphonated matter 2 117 0.10%

Modified alkane 4 111 0.090%

Polyacrylamide 2 107 0.087%

Polymer blend 3 107 0.087%

Modified thiourea polymer 4 105 0. 085 %

Amines, coco alkyl, acetates 1 104 0.085%

Terpenes and terpenoids 4 100 0. 081 %

Acrylate copolymer, sodium salt 2 99 0.081%

Sodium polyphosphate 1 99 0.081%

Ammonium alkyl sulfate 1 98 0. 080 %

Silica organic polymer 2 96 0. 078 %

Phosphonate compound 1 95 0. 077 %

Borate suspension 1 94 0. 076 %

Alkenes 3 89 0. 072 %

Formic acid additive 1 88 0.072%

Aliphatic alcohols,

ethoxylated #2 2 82 0. 067 %

Epoxy resin 3 82 0.067%

Phosphate ester 5 78 0. 063 %

Phosphonic acid derivative 3 74 0. 060 %

Polycarboxylic acid polymer 1 74 0.060%

Poly phosphonate 1 71 0. 058 %

Organo phosphorous salt 3 69 0. 056 %

Nickel chelate catalyst 3 68 0. 055 %

Acrylate phosphonate

copolymer 1 67 0.055%

Neutralized organic acid 1 67 0.055%

Resin based nonionic inhibitor 1 67 0.055%

Sodium polycarboxylate 2 65 0. 053 %

Terpene 2 65 0.053%

Mannase enzymes 1 64 0. 052 %

Poly (acrylamide

- co

- acrylic acid) 1 64 0.052%

Inorganic mineral 3 62 0. 050 %

Alcoholic amine 2 59 0. 048 %

Anionic water soluble polymer 4 56 0. 046 %

Tallow soap 3 56 0.046%

Aliphatic copolymer 2 54 0. 044 %

Alkyl sulfate 1 54 0.044%

Table continued on next page

82Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Amine phosphonate salt 1 52 0. 042 %

Modified bentonite 5 52 0.042%

Alkene sulfonate 1 51 0. 041 %

Polyamine 1 51 0. 041 %

Polysaccharide 5 51 0.041%

Quaternary ammonium 4 51 0.041%

Sulfate 1 51 0.041%

Weak acid 1 51 0.041%

Acid 1 50 0.041%

Inner salt of alkyl amines 3 49 0. 040 %

Alcohol alkoxy sulfate 1 48 0. 039 %

Ethoxylated oil 1 48 0. 039 %

Organic acid salts 1 48 0.039%

Propylene glycol copolymer 1 47 0. 038 %

Zirconium complex 2 46 0. 037 %

Aromatic amine 1 45 0. 037 %

Hemicellulase 1 45 0.037%

Inorganic material 1 44 0. 036 %

Ethoxylated alcohol linear 2 2 42 0. 034 %

Cellulose 1 41 0. 033 %

Modified amine 1 41 0. 033 %

Oxalkylated fatty acid 1 41 0.033%

Acrylate copolymer 1 40 0.033%

Alkyl amine surfactant 4 39 0. 032 %

Inorganic borate 3 39 0. 032 %

Non

- hazardous polymers 2 38 0. 031 %

Organic salt 5 37 0. 030 %

Ester solvents 1 36 0. 029 %

Cationic polymer 2 35 0. 028 %

Fatty acid amine salt mixture 6 35 0. 028 %

Polycationic organic polymer 4 35 0.028%

Synthetic resin fibers 1 34 0.028%

Amine phosphonate 7 2 33 0. 027 %

Iso

- alkanes/n

- alkanes 1 33 0. 027 %

Organic acid esters 2 33 0.027%

Oxoalkyl compounds 2 33 0.027%

Vegetable oil 2 33 0.027%

Alkylalcohol ethoxylated 1 32 0. 026 %

Table continued on next page

83Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Oxyalkalated alkyl alcohol (1) 1 32 0. 026 %

Isomeric aromatic ammonium

salt 1 31 0. 025 %

Nonylphenol 2 29 0. 024 %

Quaternized alkyl nitrogenated

compound 8 29 0. 024 %

Secondary alcohol ethoxylate 1 29 0.024%

Nonylphenol ethoxylate

surfactant 1 28 0. 023 %

Zirconium complexes (2) 1 27 0. 022 %

Cocamide based surfactant 1 25 0. 020 %

Alcohols, C12

- 16, ethoxylated 3 24 0. 020 %

Phosphorous compound 2 24 0.020%

Resin 4 23 0. 019 %

Resin compound 2 23 0. 019 %

Anionic inverse

- emulsion

polymer 1 22 0. 018 %

Aromatic ketones mixture 2 22 0. 018 %

Dimer fatty acids 2 22 0.018%

Polymers derived from fatty

acids 1 22 0.018%

Stearates 1 21 0. 017 %

Aliphatic polymer 1 20 0. 016 %

Polyanionic Cellulose 2 20 0. 016 %

Tall oil acid diethanolamide 3 20 0.016%

Amine surfactant 1 19 0. 015 %

Complex alkylamine 4 19 0. 015 %

Distillates (petroleum),

hydrotreated light 1 19 0.015%

Amine phosphonate 2 18 0.015%

Complex fatty acid compound 3 18 0.015%

Fatty acid ester 1 18 0.015%

Polyethoxylated alcohol 2 18 0.015%

Siloxane 1 18 0.015%

Alkyl quaternary ammonium

chlorides 5 17 0. 014 %

Alkylated quaternary chloride 1 17 0. 014 %

Antimonate salt 1 17 0.014%

Cocoamido tertiary amine

additive 1 17 0.014%

Emulsion polymer 1 17 0.014%

Table continued on next page

84Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Ethoxylated amine 2 17 0.014%

Fused inorganics 1 17 0.014%

Organometallic salt 2 17 0.014%

Salt of phosphate ester 2 17 0.014%

Alcohol ethoxylate C

- 10/16 with

6.5 EO 1 16 0. 013 %

Ethoxylated alcohol linear 1 1 16 0. 013 %

Ethoxylated alcohol linear 3 1 16 0.013%

Fatty alkyl heteroclyclic amine

salt 2 16 0.013%

Organo clay 2 15 0. 012 %

Sodium salt of

phosphonodimethylated

diamine 3 15 0. 012 %

Oxyalkylated ammonium salt 1 14 0. 011 %

Polyethoxylated fatty amine salt 2 14 0. 011 %

Polyurethane resin 1 14 0.011%

Quaternary ammonium chloride 3 14 0.011%

Alkyl amine salts 2 13 0.011%

Ethoxylated decyl alcohol 1 13 0.011%

Alkaline salt 2 12 0. 0098 %

Chloride compound 1 12 0. 0098 %

Complex ester 1 12 0. 0098 %

Ester mixture 1 12 0. 0098 %

Ethoxylated surfactant 1 12 0. 0098 %

Glycol 4 12 0. 0098 %

Hydrocarbon solvent 1 12 0. 0098 %

Acrylic polymer 5 11 0. 0089 %

Amine phosphate 5 1 11 0. 0089 %

Amine phosphate 5, potassium

salt 1 11 0. 0089 %

Bis quaternary compond 1 11 0.0089%

Organic chloride 1 11 0.0089%

alpha

- (4

- nonylphenyl)

- omega

hydr oxy

- , branched 2 10 0. 0081 %

Complex carbohydrate 3 10 0. 0081 %

Hydrotreated mineral oil 1 10 0. 0081 %

Propoxylated alcohol 1 10 0.0081%

Alcohols, C14

- C15, ethoxylated 3 9 0. 0073 %

Amine sulfonate 2 9 0. 0073 %

Table continued on next page

85Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Ethylene/propylene oxide

polymer 2 9 0. 0073 %

Phosphonic acid salt 1 9 0. 0073 %

Phosphonium salt 2 9 0.0073%

Oxyalkylated polymer 1 8 0. 0065 %

Oxyalkylated resin 1 8 0. 0065 %

Polyoxyalkenes 2 8 0. 0065 %

Amino compounds 1 7 0. 0057 %

Carbonates 1 7 0. 0057 %

Carboxylic acid salt 1 7 0. 0057 %

Ether salt 1 7 0.0057%

Isobutyl ketone I 1 7 0.0057%

Isobutyl ketone II 1 7 0.0057%

Isomeric aromatic ammonium 1 7 0.0057%

Modified polyacrylate 1 7 0.0057%

Phosphonate 1 7 0.0057%

Polylactide resin 2 7 0.0057%

Quaternary ammonium

compounds, dicoco

alkyldimethyl, chlorides

- TS 1 7 0.0057%

Alkoxylated alcohol 1 6 0. 0049 %

Anionic polyacrylamide

emulsion in mineral oil 1 6 0. 0049 %

Aromatic alcohol glycol ether 1 6 0. 0049 %

Cationic polyamine 1 6 0. 0049 %

Cationic polyamine blend 1 6 0.0049%

Ethoxylated alkyl amines 1 6 0.0049%

Hydrotreated petroleum

distallate 1 6 0.0049%

Mineral oil 1 6 0.0049%

Organophosphonate 2 6 0.0049%

Oxyalkylated fatty acid

derivative 2 6 0.0049%

Phosphonate of a diamine,

sodium salt 1 6 0.0049%

Alkyl phosphonate 1 5 0. 0041 %

Alkyl thiol 1 5 0. 0041 %

Alkylarylpyridinium quaternary 1 5 0. 0041 %

Amino alcohols 1 5 0. 0041 %

Carboxylate salt 1 5 0. 0041 %

Table continued on next page

86Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Citrus rutaceae extract 2 5 0.0041%

Cured resin 1 5 0.0041%

Mixed alkyl phosphate ester

(mixture) 1 5 0.0041%

Naphthenic acid ethoxylate 2 5 0.0041%

Phosphonate, amine salt 1 5 0.0041%

Polyacrylate polymer 1 5 0.0041%

Polycarboxylate 1 5 0.0041%

2,7

- Naphthalenedisulfonic acid, 1 4 0. 0033 %

Alkanolamine 2 4 0. 0033 %

Alkylpyridinium quaternary 1 4 0. 0033 %

Alphiatic polyol 1 4 0. 0033 %

Amine phosphate 1 4 0. 0033 %

Amino methylene phosphonic

acid 1 4 0.0033%

Aromatic alcohol polyglycol

ether 2 4 0.0033%

Aromatic ammonium salt 1 4 0.0033%

Aromatic hydrocarbon 2 4 0.0033%

Ester salt 1 4 0.0033%

Ethoxylated alcohol linear 1,2

and 3 1 4 0.0033%

Fatty alcohol polyglycol ether

surfactant 1 4 0.0033%

Heavy aromatic petroleum

naphtha 1 4 0.0033%

Inorganic oxygen compound 1 4 0.0033%

Modified acrylamide copolymer 2 4 0.0033%

Oxylated alcohol 2 4 0.0033%

Polyether 1 4 0.0033%

Polyoxyalkylated ether 2 4 0.0033%

Aliphatic alcohol polyglycol

ether 1 3 0. 0024 %

Aliphatic amide derivative 1 3 0. 0024 %

Amide 1 3 0. 0024 %

Amine phosphonate 7,

ammonium salt 1 3 0. 0024 %

Amino phosphonate 5 1 3 0. 0024 %

Amino phosphonate 5,

potassium salt 1 3 0.0024%

Aromatic acid derivative 1 3 0.0024%

Table continued on next page

87Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Aromatic amine, TOFA salt 1 3 0.0024%

Condensed alkanolamine 1 3 0.0024%

Dicarbonous ethoxylate 2 3 0.0024%

Ether compound 1 3 0.0024%

Ethoxylated C12

- 15 alcohols 1 3 0.0024%

Imidazolium compound 1 3 0.0024%

Phosphate acid blend 1 3 0.0024%

Phosphoric acid salt 1 3 0.0024%

Phosphorous based chemical

blend 1 3 0.0024%

Ployacrylate/phosphonate acid

blend 1 3 0.0024%

Polyester castor 1 3 0.0024%

Quaternary compound 1 3 0.0024%

Silicate mineral 2 3 0.0024%

Sulfur compound 1 3 0.0024%

Alcohol amine 1 2 0. 0016 %

Aliphatic ester 1 2 0. 0016 %

Aliphatic synthetic polymer 1 2 0. 0016 %

Alkanes 1 2 0. 0016 %

Alkyl aryl amine sulfonate 1 2 0. 0016 %

Amines, coco alkyl, ethoxylated 1 2 0.0016%

Aminofunctional polymer 1 2 0.0016%

Carboxymethylhydroxypropyl

guar blend 1 2 0.0016%

Ester 1 2 0.0016%

Ethoxylated oleyl amine 1 2 0.0016%

Formaldehyde polymer 1 2 0.0016%

Hemicellulase enzyme 2 2 0.0016%

Liquid salt 1 2 0.0016%

Non

- anionic surfactant 1 2 0.0016%

Organic amino silane 2 2 0.0016%

Organic polymer 1 2 0.0016%

Oxyalkylate polymer 1 2 0.0016%

Oxylated phenolic resin 1 2 0.0016%

Polycarboxylic acid 1 2 0.0016%

Polyoxyethylene derivative 2 2 0.0016%

Raffinates(Petroleum) 1 2 0.0016%

Salt of aliphatic acid 1 2 0.0016%

Table continued on next page

88Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Silicane derivative 2 2 0.0016%

Sodium xylene sulfonate 1 2 0.0016%

Terpenes and terpenoids, sweet

orange

- oil 1 2 0.0016%

Terpolymer sodium salt 1 2 0.0016%

Acrylamide copolymer 1 1 0. 00081 %

Acrylic acid polymer 1 1 0. 00081 %

Alcohol amine salts 1 1 0. 00081 %

Alcohol ethoxylate distillate 1 1 0. 00081 %

Alcohol ethoxylates 1 1 0. 00081 %

Alkalines 1 1 0. 00081 %

Alkanolamine chelate of

zirconium 1 1 0.00081%

Alkanolamine chelate of

zirconium alkoxide 1 1 0.00081%

Alkenens, C15

- C18 1 1 0.00081%

Alkkoxylated alkylphenol 1 1 0.00081%

Alkyl sulfonate 1 1 0.00081%

Alkyl sulfonate amine salts 1 1 0.00081%

Alkylamine halide salt 1 1 0.00081%

Alkylamine salts 1 1 0.00081%

Alkylammonium 1 1 0.00081%

Alkylbenzenesulfonic acid 1 1 0.00081%

Amine phosphate 1 1 1 0.00081%

Amphoteric alkyl amine 1 1 0.00081%

Aromatic polymer 1 1 0.00081%

Chloromethylnapthalene

quinoline quaternary amine 1 1 0.00081%

Citrus terpenes 1 1 0.00081%

Copolymer resin 1 1 0.00081%

Cycloparrafins 1 1 0.00081%

Derivative of acrylic acid

copolymer 1 1 0.00081%

Enzyme protein 1 1 0.00081%

Ethoxylated lauryl alcohol 1 1 0.00081%

Fatty amine quaternary 1 1 0.00081%

Guar

- carbohydrate 1 1 0.00081%

Guar gum 1 1 0.00081%

Heavy aromatic petroleum 1 1 0.00081%

Hydrotreated light 1 1 0.00081%

Table continued on next page

89Analysis of Data from FracFocus 1.0 March 2015

Standardized chemical

family name Number of chemical

names with this

standardized family

name * Number of CBI

ingredient records CBI records as percent

of total CBI

ingredient records

Hydrotreated paraffinic solvent 1 1 0.00081%

Metal chloride 1 1 0.00081%

Methanol complex fatty

- acid

compound 1 1 0.00081%

Modified acrylate polymer 1 1 0.00081%

Modified cycloaliphatic amine 1 1 0.00081%

m

- olefins 1 1 0.00081%

Noionic fluorsurfactant 1 1 0.00081%

Non hazardous sodium

polyacrylate solution 1 1 0.00081%

Non

- hazardous synthetic acid 1 1 0.00081%

Olefins oganic salt 1 1 0.00081%

Oranophilic clay 1 1 0.00081%

Organic acid zirconium salt 1 1 0.00081%

Organic amine 1 1 0.00081%

Organic phosphonate salts 1 1 0.00081%

Organophosphorous salt 1 1 0.00081%

Oxyalkylated fatty amine 1 1 0.00081%

Polacrylamide copolymer 1 1 0.00081%

Poly(dimethylaminoethyl

methacrylate dimethyl sulfate

quat) 1 1 0.00081%

Polyamine polymer 1 1 0.00081%

Polyolycol ester 1 1 0.00081%

Quarternary ammonium salt 1 1 0.00081%

Quaternary amine compounds 1 1 0.00081%

Quaternary heteropolycycle salt 1 1 0.00081%

Resin coated cellulose 1 1 0.00081%

Sodium carboxylate 1 1 0.00081%

Sodium salt of aliphatic amine

acid 1 1 0.00081%

Sodium salt

phosphonodimethylated 1 1 0.00081%

Surface base on cocamide 1 1 0.00081%

Zirconium salt solution 1 1 0.00081%

Zirconium/triethanolamine

complex 1 1 0.00081%

Total 97, 610 79%

* Counts in this column represent the number of distinct combinations of chemical name and CASRN (for example, “borate

salts” with a CASRN of “CBI” and “borate salts” with a CASRN of “Confidential” are counted separately).

90Analysis of Data from FracFocus 1.0 March 2015

Table B

- 2. Most frequently reported chemical families among CBI ingredients and their most commonly listed

purposes.

Standardized chemical

family name Most commonly listed purposes for additives containing the chemical

Alcohol ethoxylate

surfactants Friction Reducers, Corrosion Inhibitors, Surfactants

Aliphatic acids Corrosion Inhibitors

Aliphatic alcohols,

ethoxylated #1 Corrosion Inhibitors

Aliphatic hydrocarbon Surfactants, Scale Control, Friction Reducers

Alkylene oxide block

polymer Surfactants, Corrosion Inhibitors, Sca le Control

Amino alkyl phosphonic acid Scale Control

Aromatic aldehyde Corrosion Inhibitors

Carbohydrate polymer Gelling Agents and Gel Stabilizers

Copolymer Surfactants, Scale Control, Solvents

Cured acrylic resin Surfactants, Breakers and Breaker Catalysts, Scale Control

Fatty acids Corrosion Inhibitors, Clean Perforations

Olefins Corrosion Inhibitors, Iron Control Agents, Clean Perforations, Gelling Agents

and Gel Stabilizers

Organic amine resin salt Corrosion Inhibitors

Oxyalkylated alcohol Non

- Emulsifiers, Surfactants, Friction Reducers, Scale Control

Petroleum distillates Gelling Agents and Gel Stabilizers, Solvents, Friction Reducers, Crosslinkers and

Related Additives

Polyglycol ester Surfactants, Scale Control, Solvents, Biocides

Poly ol ester Surfactants, Scale Control, Solvents, Biocides

Polyoxyalkylenes Corrosion Inhibitors, Clean Perforations

Quaternary ammonium

compounds Corrosion Inhibitors, Non

- Emulsifiers, Surfactants

Vinyl copolymer Surfactants, Scale Control, Solvents

Note: Analysis considered 36,544 disclosures and 1,218,003 ingredient record s that met selected quality assurance criteria

, including: completely parsed; unique combination of fracture date and API well n umber; and fracture date between

January 1, 2011, an d February 28, 2013. Disclosures that did not meet quality assurance criteria (1,986 disclosures) or

other, query

- specific criteria were excluded from analysis.

91Analysis of Data from FracFocus 1.0 March 2015



# Appendix C. Histograms of Hydraulic Fracturing Fluid

Concentrations for Most Frequently Reported Additive

Ingredients

The histograms in this appendix display the distributions of the median maximum hydraulic

fracturing fluid concentrations for the twenty most frequent ly reported additive ingredients

. The

graphs were developed to supplement the data provided in Table s 8 and 9 by providing a visual

display data that can help in assessing how effectively the median indicates central tendency for

these additive ingredients

. Graphs indicate the median for oil wells (graph heading “Oil”) , gas wells

(“Gas”) , and oil plus gas wells ( “A ll disclosures ” ) for the entire project database and are displayed

with both a linear x

- axis scale and a log normal x

- axis scale.

The data for t he histograms were based on the QA criteria used to produce Table s 8 and 9. The data

included in analyses came from unique disclosures (unique combin ation of fracture date and API

well n umber) with fracture dates between January 1, 2011, and February 28, 2 013, successfully

parsed ingredients data, valid CASRNs for ingredient records, and valid additive and fluid

concentrations for ingredient records.

92Analysis of Data from FracFocus 1.0 March 2015

93Analysis of Data from FracFocus 1.0 March 2015

94Analysis of Data from FracFocus 1.0 March 2015

95Analysis of Data from FracFocus 1.0 March 2015

96Analysis of Data from FracFocus 1.0 March 2015

97Analysis of Data from FracFocus 1.0 March 2015

98Analysis of Data from FracFocus 1.0 March 2015

99Analysis of Data from FracFocus 1.0 March 2015

100Analysis of Data from FracFocus 1.0 March 2015

101Analysis of Data from FracFocus 1.0 March 2015

102Analysis of Data from FracFocus 1.0 March 2015

103Analysis of Data from FracFocus 1.0 March 2015

104Analysis of Data from FracFocus 1.0 March 2015

105Analysis of Data from FracFocus 1.0 March 2015

106Analysis of Data from FracFocus 1.0 March 2015

107Analysis of Data from FracFocus 1.0 March 2015

108Analysis of Data from FracFocus 1.0 March 2015

109Analysis of Data from FracFocus 1.0 March 2015

110Analysis of Data from FracFocus 1.0 March 2015

111Analysis of Data from FracFocus 1.0 March 2015



# Appendix D. List of Operators

Table D

- 1. Disclosure s per state , summarized by well operator (428 operators included in the project database ).

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

**Unspecified** 8 2 3 2 19 34

3

- M Energy Corporation 4 4

Abraxas Petroleum Corporation 1 1 4 1 7

Aera Energy 447 447

Alpha Shale Resources LP 5 5

Alta Mesa Holdings 1 1

Amerada Hess Corporation 1 1

Amexco LLC 1 1

Anadarko E & P Company LP 1 4 5

Anadarko E&P Onshore LLC 11 44 55

Anadarko Petroleum Corporation 1 7 171 621 654 101 1 1556

Anschutz Exploration Corporation 3 3 6

Antero Resources 25 20 45

Apache Corporation 1 2 278 112 1078 9 1480

Apollo Operating, LLC 15 15

Approach Resources 22 22

Arabella Petroleum Company LLC 2 2

ARCO Permian 1 1

Argent Energy (US) Holdings 1 1

Aruba Petroleum 23 23

Athlon Energy 99 99

Athlon Energy Operating 1 1

Athlon Fe Operating LLC 4 4

Atlantic Operating 7 7

Table continued on next page

112Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Atlas 2 2

Atlas Barnett LLC 5 5

Atlas Energy, L.P. 25 2 27

Austin Exploration, Inc. 2 2

Axia Energy LLC 2 11 13

Aztec Drilling and Operating 30 30

BASA Resources, Inc. 5 5

Bass Enterprises Production Company 7 7

Bayswater Exploration and Production 43 43

Baytex Energy USA LTD 21 21

BC Operating 1 46 47

Berry Oil Company 5 5

Berry Petroleum 2 45 29 76

Best Petroleum Exploration 6 6

BHP Billiton Petroleum 138 111 262 3 514

Big Star Oil & Gas LLC 19 19

Bill Barrett Corp 190 140 4 2 336

Bird Creek Resources Inc. 1 1

Black Hills Exploration and Production 1 1

Black Hills Plateau Production 1 1

Black Raven Energy 19 19

Blackbrush Oil and Gas 17 17

BLS Production 3 3

Bluestem Energy 16 16

Bluestone Natural Resources 8 8

BLX Inc 2 2

Boaz Energy LLC 1 1

Table continued on next page

113Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Bonanza Creek Energy, Inc. 121 121

BP America Production Company 17 9 51 43 230 350

Brammer Engineering 1 1

Breck Operating Corporation 3 3

Bridwell Oil Co. 6 6

Brigham 9 102 2 113

BTA Oil Producers 4 4 8

Burk Royalty Co., LTD 10 10

Burlington Resources Oil and Gas

Company 8 12 1 51 72

Burnett Oil Co., Inc. 4 4

BVX Operating Inc 5 5

Cabot Oil & Gas Corp 14 155 44 213

Callon Petroleum Company 1 1

Canan Operating, Inc. 4 4

Cannon Oil and Gas 1 1

Capstone Natural Resources, LLC 1 4 5

Carrizo Oil and Gas Inc. 30 35 56 121

Cazar Energy, Inc. 1 1

Cd Consulting and Operating Company 1 1

Chaparral Energy 10 6 2 18

Chesapeake Energy 1 1

Chesapeake Operating, Inc. 46 22 5 277 6 23 130 608 383 1414 114 61 3089

Chevron USA Inc. 21 72 62 5 102 492 9 1 764

Cheyenne Petroleum Company 22 22

Chief Oil & Gas 88 88

Choice Exploration, Inc. 2 2

Cimarex Energy Company 70 60 46 176

Table continued on next page

114Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Cinco Resources 7 2 9

Cirque Resources LP 3 3

Citation Oil and Gas 2 45 35 1 83

Citrus Energy Corporation 11 11

Clayton Williams Energy, Inc. 1 46 1 48

Clear Fork Inc 3 3

CML Exploration 8 8

Cobra Oil and Gas Corporation 24 24

Collins & Ware Inc 1 1

Compass 33 33

Comstock Oil & Gas 21 71 92

Concho Operating Group 4 314 318

Condor Energy 1 1

ConocoPhillips Company 17 3 60 227 346 2 655

CONSOL Energy Inc. 1 91 10 1 103

Continental Resources, Inc 8 43 291 78 1 2 423

Corinthian Exploration Corp. 5 5

Corlena Oil Company 10 10

Crescent Energy 19 2 21

Crimson Exploration Inc. 6 6

Crown Equipment Corporation 1 1

CrownQuest 128 1 129

David H. Arrington Oil and Gas 2 2

Delta CO2, LLC 2 2

Delta Oil and Gas 29 29

Denali Oil and Gas 2 2

Denbury Resources 25 25

Table continued on next page

115Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Devon Energy Corporation 25 25

Devon Energy Production Company L. P. 9 3 128 5 199 1027 4 51 2 1428

Diamondback E&P LLC 21 21

Diamondback Energy 12 12

Diamondback Resources LLc 1 1

Discovery Operating 6 6

DTE Gas Resources, LLC 35 35

Eagle Energy Acquisitions LP 11 11

Eagle Rock Energy 1 1

EagleRidge Energy, LLC 11 11

Edge Barnett Operating Company 1 1

EF Energy 6 6

EGL Resources, Inc. 9 9

El Paso E&P Company 13 63 30 89 27 9 231

Element Petroleum Operating, LLC 13 13

Elk Prod Uintah Llc 1 1

Elm Ridge Exploration Company, LLC 3 3

Empresa Energy LP 1 1

Encana Oil & Gas (USA) Inc. 787 3 132 5 4 8 74 193 1206

Endeavor Energy Resources 94 94

Enduring Resources II, LLC 8 8

Energen Resources Corporation 55 1 8 21 804 889

Energy Corporation of America 35 8 43

Enerplus 24 24

EnerQuest Operating LLC 1 1

Enervest Energy Partners LP 1 1

EnerVest, Ltd. 1 11 127 5 144

Table continued on next page

116Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Entek Energy, Ltd. 2 2

EOG Resources, Inc. 37 17 13 158 33 53 87 1381 20 18 5 1822

Eor Operating Co 1 1

EP Energy 7 65 16 23 111

EP Energy E&P Company LP 3 3

EQT Production 54 43 97

Equal Energy Us Inc 3 3

Estancia Oil & Gas LLC 3 3

EV Energy Partners 14 14

EXCO Resources, Inc. 136 74 82 292

EXL Petroleum 10 10

Extex Operating Company 4 4

ExxonMobil 89 49 6 1 46 191

Fair Oil Limited 2 2

Fairway Resources 1 1 2

Fairways Exploration and Production,

LLC 1 1

Fasken Oil and Ranch, Ltd. 114 114

FIML Natural Resources, LLC 160 160

Finley Resources, Inc. 12 3 9 24

Fivestones Energy LLC 1 1

Foree Oil Company 4 4

Forest Oil Corporation 5 4 5 43 1 58

Forge Energy LLC 8 8

Franks Operating Company, LLC 1 1

Front Range Oil & Gas 3 3

G3 Operating, LLC. 1 17 4 22

GeoResources 2 2

Table continued on next page

117Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

GeoSouthern Energy Corporation 5 5

Getty Oil Company 2 2

GMX Resources Inc 5 5

Goodrich Petroleum Company, LLC 1 24 25

Gordon Creek LLC 8 8

Gosney & Sons Inc. 1 1

Great Plains Operating LLC 1 2 3

Great Western Oil and Gas Company 76 76

Guinn Investments, Inc 1 1

Gulf Oil Corporation 3 3

Gunn Oil Company 2 2

Gunnison Energy Corporation 3 1 4

H&L Exploration Company 4 4

Hadaway Consulting and Engineering,

LLC 2 2

Halcon Resources 2 43 45

Hannathon Petroleum LLC 6 6

Helis Oil & Gas Company, LLC 9 9

Henry Resources, LLC 78 2 80

Hess Corporation 377 20 3 33 4 437

Hibernia Resources, LLC 5 5

HighMount Exploration & Production 30 103 133

Hilcorp Energy Company 1 1

Howell Petro. Corp. 222 222

Hunt Oil Company 17 1 11 50 2 81

Huntington Energy LLC 2 2

Indigo II Louisiana Operating, LLC 1 1

Indigo Minerals 39 1 40

Table continued on next page

118Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Ironwood Oil & Gas LLC 5 5

J CLEO THOMPSON 101 101

JAMEX INC 2 2

JDL Operating, LLC 1 1

Jetta Operating Company 4 3 7

Johnson And Ernst Operating Company 6 6

Jones Energy 12 12 24

Juno Operating Company II, LLC 51 51

J

- W Operating Company 28 1 5 34

K.P. Kauffman Company 18 18

Kaler Energy Corporation 1 1

Keith F. Walker Oil and Gas Company 2 2

KERR

- MCGEE OIL & GAS ONSHORE LP 1250 1 1251

Keystone Petroleum LP 1 1

Killam Oil Co Ltd 4 4

Kinder Morgan 2 2

Kodiak Oil & Gas Corporation 64 64

Lakota Energy Ltd 2 2

Laredo Petroleum, Inc. 13 296 309

Layline Petroleum LLC 20 20

LCS Production Company 16 16

Le Norman Operating LLC 16 2 18

LeClair Operating Co., Inc. 1 1

Legacy Reserves Operating LP 6 6

Legado Permian, LLC 13 13

Legend Natural Gas, LLC 1 48 1 50

Lewis Energy Group 78 78

Table continued on next page

119Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Lewis Operating Corporation 1 1

Liberty Resources LLC 21 21

Limestone Exploration II, LLC 1 1

Linn Energy, LLC 3 112 115

Llewellin Operating Company 1 1

Louis Dreyfus Highbridge Energy 1 1

Lowe Royalty Partners LP 1 1

LP Operating, LLC 2 2

M & A Oil Co Ltd 1 1

Magnet Oil 1 1

Magnum Hunter Resources Corporation 12 3 15

Marathon Oil 23 5 172 55 261 127 1 644

Mariner Energy Inc 1 1

Marlin Oil Corporation 2 2

Matador Production Company 14 14

McClure Oil Company 1 1

McElvain Energy Inc. 1 1 2

MDS Energy Development LLC 7 7

MDU Resources 10 32 8 50

Medders Oil Company, Inc 1 1

Merit Energy Company 36 36

Meritage Energy Co. 2 2

Mesa Energy Partners, LLC 7 7

Mestena Operating Ltd. 2 2

Mewbourne Oil Company 13 52 65

Midenergy Operating LLC 4 4

Midland Oil And Gas, Inc. 4 4

Table continued on next page

120Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Mid

- States Operating Company 5 5

Milagro Exploration, LLC 1 1

Mitchell Energy and Development

Corporation 1 1

Mohican Operating LLC 3 3

Molopo Energy Texas LLC 6 6

Momentum Oil & Gas LLC 1 1

Mountain V Oil & Gas 7 7

Murphy Exploration and Production 113 113

MWS Producing Inc. 6 6

Navidad Resources, LLC 7 7

New Gulf Resources, LLC 2 2 4

Newark E&P Operating, LLC 13 13

Newfield Exploration 4 46 54 56 437 597

Newfield Production Company 1 1

NFR Energy, LLC 8 1 9

NMR Energy 2 2

Noble Energy, Inc. 942 20 4 1 967

NorthStar Operating Company 1 1

Oasis Petroleum 33 69 2 104

O'Brien Energy Company 1 1

Occidental Permian Ltd 7 7

Occidental Petroleum Corporation 93 184 37 66 65 1 655 6 1107

Ohio Valley Energy Systems Corp. 1 1

Omni Oil and Gas, Inc. 230 230

Opal Resources Operating Company 18 18

Osborn Heirs Company 1 1

Overland Resources LLC 3 3

Table continued on next page

121Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

P O & G Operating LLC 5 5

Pacesetter Energy LLC 2 2

Paloma Resources 10 10

Parallel Petroleum, LLC 15 15

Parsley Energy Operations 84 84

Partee Drilling Company 4 4

Parten Operating Inc. 1 1

Patara Oil & Gas, LLC 6 2 9 17

Patriot Resources, Inc. 31 31

PDC Energy 56 17 11 84

Peak Powder River Resources LLC 1 1

Peak Resources, LLC 4 4

Pecos Operating Company LLC 5 5

Penn Virginia Oil & Gas Corporation 1 60 1 62

Pennsylvania General Energy 62 2 64

PETEX 9 9

Petroglyph Operation Company 23 23

Petrohawk Energy Corporation 8 64 4 76

Petro

- Hunt, LLC 77 2 79

Petroquest Energy, Inc. 31 6 3 40

Piceance Energy LLC 2 2

Piedra Resources, Ltd. 6 6

Pioneer Natural Resources 3 80 3 1500 1586

Pitts Energy Company 5 5

Plains Exploration & Production

Company 2 167 2 1 172

Plantation Petroleum Company Inc. 5 5

Price Operating LLC 20 20

Table continued on next page

122Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Primexx Energy Partners 7 7

Propel Energy, LLC 3 3

Prospect Energy LLC 6 6

QEP Energy Company 38 11 18 3 4 119 193

Quantum Resources Management, LLC 3 26 29

Questar 5 33 38

Quicksilver Resources, Inc. 4 23 27

Range Operating New Mexico, Inc. 2 2

Range Resources Corporation 27 277 20 90 1 415

Red Willow Production Company 1 2 3

Reliance Energy, Inc. 47 1 48

Renegade Oil and Gas 4 4

Resolute Energy 26 6 32

Rex Energy 1 41 3 45

Rice Drilling B, LLC 7 7

Ricochet Energy 3 3

Rife Energy 1 1

Riley Exploration, LLC 3 3

RIM Operating, Inc. 1 1

RK Petroleum 8 8

RKI Exploration and Production 15 1 16

Robert Bayless Producer LLC 2 2

Roff Operating Company 4 4

Roff Resources 2 2

Rosetta Resources, Inc. 5 67 72

Rosewood Resources 1 1

Royalty Land & Development

Corporation 1 1

Table continued on next page

123Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

RSP Permian, LLC 52 52

S.B. Street Operting Inc. 6 6

Sabine Oil & Gas 3 3

Sahara Operating Company 1 1

Samson Oil & Gas Ltd 6 10 4 62 14 60 45 201

Sandalwood Oil and Gas Exploration

and Production 1 1

SandRidge Energy 56 4 188 653 2 903

Santa Fe Energy Resources Inc. 1 1

Schlachter Operating Corporation 3 3

Seaboard Oil Company 3 3

Seaboard Operating Company 3 3

Seneca Resources Corporation 7 82 89

Sequel Energy, LLC 2 2

SG Interests Inc. 1 1

Sharp Image Energy, Inc. 2 2

Shell Exploration & Production

Company 12 100 224 99 73 508

Silver Creek Oil & Gas, LLC 3 3

Sinclair Oil & Gas Company 1 5 6

Slawson Exploration Company, Inc. 19 23 2 1 1 46

SM Energy 2 58 10 20 162 9 2 263

Snyder Brothers, Inc. 21 21

Southern Bay Operating, L.L.C. 9 9

Southwest Royalties, Inc. 21 21

Southwestern Energy 964 1 4 71 6 1046

Stanolind Operating 1 1

Statoil 3 23 26

Table continued on next page

124Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Steller Energy and Investment 5 5

Stephens and Johnson Operating

Company 4 1 7 12

Steward Energy, LLC 1 1

Stone Energy Corporation 21 21

Stout Energy 2 2

Strat Land Exploration Company 3 5 9 17

Suemaur Exploration and Production

LLC 4 4

Summit Oil and Gas 2 2

Summit Petroleum 29 29

Sundance Energy 15 15

Swift Energy Company 68 1 69

Sydson Energy, Inc 1 1

Synergy Resources Corporation 41 41

Tacor Resources Inc. 3 3

Talisman Energy USA Inc. 179 111 7 297

Tanos Exploration, LLC 3 3

TAQA North Ltd. 20 20

Tecpetrol Operating LLC 16 1 17

Tekton Windsor Llc 3 3

Telesis Operating Company 1 1

Tema Oil and Gas Company 1 1

Tenneco Inc. 1 1

Texaco Inc. 12 12

Texakoma Operating 5 5

Texas Energy Operations, LLC 2 2

Texas International Operating, LLC 3 3

Table continued on next page

125Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Texas Royalty Corporation 2 2

Texland Petroleum, LP 1 21 22

Texon Oil Company 2 2

The Cumming Company 8 8

The Termo Company 1 1 2

Thompson Engineering and Production

Company 2 2

Three Rivers Operating Company 27 27

Thums Long Beach Co 2 2

Timmerman 5 5

Titan Operating, LLC 41 41

Trap Rock Oil, Ltd. 3 3

Treadstone Energy Partners LLC 9 9

Trey Resources Inc. 2 2

Triana Energy 4 4

Triangle Petroleum Corporation 14 14

Tri

- C Resources, LLC 3 3

Trilogy Resources LLC 7 7

Trio Operating Company 4 4

Trivium Operating LLC 3 3

True Oil LLC 2 2

Tug Hill Operating 6 6

Ultra Resources 1 6 144 151

Unit Petroleum 6 36 42

US Enercorp Ltd 2 2

Vaalco Energy Inc. 3 3

Valence Operating Company 20 20

Vanguard Permian LLC 1 1

Table continued on next page

126Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

Vantage Energy 1 1

Vantage Energy Appalachia LLC 4 4

Vantage Fort Worth Energy LLC 10 10

Venoco Inc. 20 20

Veritas Energy, LLC 11 11

Vintage Production of California 36 36

W&T Offshore 94 1 95

Walsh and Watts, Inc. 10 10

Walsh Petroleum 8 8

Walter Exploration Company 10 10

Wapiti Operating Llc 3 3

Ward Petroleum 11 11

Warren American Oil Company 5 5

Wellstar Corporation 3 3

WG Operating 9 9

Whiting Petroleum 19 7 24 208 175 1 1 435

William H. Lackey Oil & Gas 2 2

Williams Production 340 12 38 18 408

Willowbend Investments 4 4

Windsor Permian, LLC 8 8

Wolverine Gas & Oil Corporation 1 1

Woodbine Acquisition, LLC 11 11

Woolsey Operating Company 2 2

WPX Energy 300 49 50 7 406

XTO Energy 297 60 20 5 66 98 150 62 1092 20 23 1 6 1900

Zavanna, LLC 26 26

Table continued on next page

127Analysis of Data from FracFocus 1.0 March 2015

Operator Number of disclosures

AK AL AR CA CO KS LA MI MS MT ND NM OH OK PA TX UT VA WV WY N/A All

ZaZa Energy Services 18 18

Zenergy Operating Company 25 1 26

Note: Analysis considered 38,050 disclosures and 428 operators that met selected quality assurance criteria , including: unique combin ation of fracture date and API well

n umber and fracture date between January 1, 2011, and February 28, 2013. Disclosures that did not meet quality assurance criteria were excluded from analysis (480).

128Analysis of Data from FracFocus 1.0 March 2015



# Appendix E. Reporting Requirements for States with

Data in the Project Database

Table E

- 1 presents information on report ing requirements for the 20 states with data in the project

database , as of February 28, 2013. Table E

- 1 also shows the number of unique disclosures with

fracture dates between January 1, 2011, and February 28, 2013 , for each state

. Fourteen of 20

states with data in the project database enacted reporting requirements either before or during the

time period studied in this report. Six of those states (Colorado, North Dakota, Oklahoma,

Pennsylvania, Texas, and Utah) mandated reporting to FracFocus. The other eight states required

reporting to the state or to either the state or FracFocus. Six of the 20 states with data in the project

database had no rep orting requirements in effect prior to February 28, 2013.

Table E

- 1. Reporting regulations for states with data in the project database.

State Regulatory

effective date State regulation Number of disclosures

Alabama None

-- 55

Alaska None

-- 37

Arkansas 1/15/2011 State Rule B

- 19. Applicable to wells issued a

new drilling permit on or after effective date.

Report to the state within 30 days of well

completion or recompletion. 1,450

California None

-- 718

Colorado 4/1/2012 State regulation Rule 205A. Applicable to all

hydraulic fracturing treatments performed on

or after effective date. Reporting must occur

within 60 days after the conclusion of

fracturing, or no later than 120 days after

commencement. Reporting is required to

FracFocus. 4,938

Kansas None

-- 136

Louisiana 10/20/2011 State regulation LAC 43:XIX.118. Applicable to

all new wells issued an initial drilling permit

on or after effective date. Reporting to the

state must occur within 20 days after the

conclusion of fracturing. Alternatively,

reporting may be made to FracFocus or any

other similar registry. 1,038

Michigan 6/22/2011 State Supervisor of Wells Instruction 1

- 2011.

Applicable to large water withdrawals

(average of 100,000 gallons per day over 30

day period) on or after effective date.

Reporting to the state must occur within 60

days after well completion. 15

Mississippi None

-- 4

Table continued on next page

129Analysis of Data from FracFocus 1.0 March 2015

State Regulatory

effective date State regulation Number of disclosures

Montana 8/26/2011 State regulation 36.22.1015. Applicable to all

treatments performed on or after effective

date. Reporting to the state must occur upon

well completion or treatment. Alternatively,

reporting may be made to FracFocus. 213

New Mexico 2/15/2012 State regulation NMAC 19.15.16.19.

Applicable to all treatments on or after

effective date. Reporting to the state within

45 days after completion of well. 1,162

North

Dakota 4/1/2012 State regulation 43

- 02

- 03

- 27.1. Applicable to

all treatments performed on or after

effective date. Reporting to FracFocus must

occur within 60 days after the conclusion of

fracturing. 2,254

Ohio 9/10/2012 State regulation ORC 1509.10. Applicable to

hydraulic fracturing performed on or after

effective date. Reporting to the state must

occur within 60 days after the conclusion of

fracturing. Alternatively, reporting may be

made to FracFocus or other means

acceptable to the state. 148

Oklahoma 1/1/2013 State regulation OA C 165:10

- 3

- 10. Applicable

to horizontal wells hydraulically fractured on

or after effective dates. Reporting to

FracFocus (or to the state, which will post the

information to FracFocus) must occur within

60 days after the conclusion of fracturing.

Regulati on effective for other wells that are

hydraulically fractured on January 1, 2014. 1,909

Pennsylvania 2/5/2011 State statute 78.122. Applicable to wells

completed on or after the effective date.

Reporting to the state must occur within 30

days after completion.

2,483

4/14/2012 State statute 58.3222 and 3222.1 . Applicable

to hydraulic fracturing of unconventional

wells performed on or after effective date.

Reporting to FracFocus must occur within 6 0

days after conclusion of fracturing. Reporting

is also required to the state agency within 30

days after well completion

.

Texas 2/1/2012 State regulation 16 TAC 3.29. Applicable to

wells issued an initial drilling permit on or

after effective date. Reporting to FracFocus

must occur within 30 days of well completion

or 90 days after drilling operation is

completed (whichever is earlier). 18 ,075

Table continued on next page

130Analysis of Data from FracFocus 1.0 March 2015

State Regulatory

effective date State regulation Number of disclosures

Utah 11/1/2012 State regulation R649

- 3

- 39. Applicable to

hydraulic fracturing performed on or after

effective date. Reporting to FracFocus must

occur within 60 days after the conclusion of

fracturing. 1,429

Virginia None

-- 90

West

Virginia 8/29/2011 Emergency rule § 35

- 8 . Applicable to

horizontal wells issued permits after effective

date and which withdraw more than 210,000

gallons of water per month. Reporting to the

state is required within 90 days after well

completion.

277

12/14/2011 WV Code §§ 22

- 6A

- 7. Applicable to horizontal

wells issued permits after effective date and

which disturb more than three acres of

surface or operations withdrawing more than

210,000 gallons of water per month.

Reporting to the state is required within 90

days after well completion.

Wyoming 8/17/2010 State regulation Wyoming Code of Rules and

Regs. Chapter 3. Applicable to new drilling

permits approved on or after effective date.

Reporting to the state prior to stimulation

and within 30 days after completion. 1,457

Note: Analysis considered 37,888 disclosures that met selected quality assurance criteria , including: unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and with confirmed

state location. Disclosures that did not meet quality assurance criteria were excluded from analysis (642 disclosures).

131Analysis of Data from FracFocus 1.0 March 2015



# Appendix F. Additive Purposes

Ta ble F

- 1. Number of disclosures, summarized by additive purpose categories

.

EPA

- standardized a dditive purpose Number of disclosures Number of ingredient

records reported as CBI

Proppants 27,943 896

Biocides 27,057 3,339

Breakers and breaker catalysts 22,283 5,325

Friction reducers 18,935 6,618

Crosslinkers and related additives 18,353 7,137

Gelling agents and gel stabilizers 18,243 7,719

Acids 18,138 266

Corrosion i nhibitors 17,824 21,519

Surfactants 17,778 21,581

Base fluid 16,112 486

Scale control 15,335 13,090

Iron control agents 13,472 1,071

Clay control 11,432 4,526

pH control 11,200 245

Non

- emulsifiers 10,943 7,587

Other/Multiples 4,207 1,406

Solvents 4,115 2,551

Activators 2,652 1,031

Inhibitors 1,998 1,129

Resin curing agents 1,473 422

Clean perforations 1,373 955

Fluid foaming agents and energizers 1,262 147

Stabilizers 917 198

Viscosifiers 900 455

Reducing agent 796 4

Acid inhibitors 786 378

Fluid loss additives 604 139

Oxidizer 513 5

Emulsifiers 510 44

Oxygen scavengers 428 218

Antifoaming agents 351 349

Flow enhancers 247 91

Tracers 200 1,127

Sulfide scavengers 190 161

Sealers 136 70

Formation breakdown 87 0

Antisludge agents 57 4

Table continued on next page

132Analysis of Data from FracFocus 1.0 March 2015

EPA

- standardized a dditive purpose Number of disclosures Number of ingredient

records reported as CBI

Antifreeze 45 0

Flowback control 44 64

Fluid diverters 3 3

Delaying agents 1 0

Proppant r esin 1 1

Note: Analysis considered 36,544 disclosures and 1,218,003 ingredient records that met selected quality

assurance criteria, including: completely parsed; unique combination of fracture date and API well number; and

fracture date between January 1, 2011, and February 28, 2013. Disclosures not meeting quality assurance criteria

(1,986) or other, query

- specific criteria were excluded from analysis.

133Analysis of Da ta from FracFocus 1.0 March 2015



# Appendix G. Most Frequently Reported Additive Ingredients for Five Selected

Counties

Table G

- 1. Twenty most frequently reported additive ingredients in Andrews County, Texas, ranked by frequency of occurrence

.

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Methanol 67

- 56

- 1 885 (81%) 0.022 0.0014 0.11 1

, 570 (8.8%) 50 5.0 96

Peroxydisulfuric acid,

diammonium salt 7727

- 54

- 0 852 (78%) 0.010 0.0017 0.045 929 (5.2%) 100 60 100

Ethylene glycol 107

- 21

- 1 765 (70%) 0.030 0.0083 0.13 959 (5.4%) 40 10 69

Glutaraldehyde 111

- 30

- 8 724 (67%) 0.013 0.0033 0.020 724 (4.0%) 15 14 30

Sodium hydroxide 1310

- 73

- 2 563 (52%) 0.010 0.00013 0.028 606 (3.4%) 10 2.0 30

Potassium hydroxide 1310

- 58

- 3 544 (50%) 0.025 0.0015 0.057 554 (3.1%) 23 0.17 50

Distillates, petroleum,

hydrotreated light 64742

- 47

- 8 527 (48%) 0.23 0.0025 0.35 671 (3.8%) 55 21 70

Tetradecyl dimethyl

benzyl ammonium

chloride 139

- 08

- 2 521 (48%) 0.0046 0.0012 0.0062 521 (2.9%) 5.0 5.0 5.0

Hydrochloric acid 7647

- 01

- 0 457 (42%) 0.53 0.15 4.3 486 (2.7%) 20 4.3 60

Isopropanol 67

- 63

- 0 439 (40%) 0.014 0.00038 0.35 537 (3.0%) 30 0.60 100

Water 7732

- 18

- 5 417 (38%) 1.3 0.0017 14 815 (4.6%) 72 5.0 97

Guar gum 9000

- 30

- 0 407 (37%) 0.17 0.032 0.36 407 (2.3%) 50 1.1 100

Alcohols, C12

- 14

- secondary, ethoxylated 84133

- 50

- 6 391 (36%) 0.026 0.0021 0.053 395 (2.2%) 70 7.0 70

Quartz 14808

- 60

- 7 363 (33%) 0.0028 0.000070 8.8 415 (2.3%) 5.0 1.0 89

Polyethylene glycol 25322

- 68

- 3 331 (30%) 0.0018 0.00016 0.0045 334 (1.9%) 5.0 0.016 5.0

2

- Butoxyethanol 111

- 76

- 2 304 (28%) 0.011 0.000068 0.33 334 (1.9%) 1.1 0.10 60

Propargyl alcohol 107

- 19

- 7 290 (27%) 0.00040 0.000070 0.0049 301 (1.7%) 5.0 0.0082 35

Sodium chloride 7647

- 14

- 5 260 (24%) 0.026 0.00026 0.29 291 (1.6%) 40 0.081 100

Citric acid 77

- 92

- 9 205 (19%) 0.0078 0.0012 0.028 230 (1.3%) 70 7.0 70

Acetic acid 64

- 19

- 7 198 (18%) 0.0061 0.00000 * 0.047 221 (1.2%) 50 5.0 100

* Concentration is less than a millionth of a percentage by mass.

Note: Analysis considered 1,088 disclosures and 20,716 ingredient record s that met selected quality assurance criteria , including: completely parsed; unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; with confirmed state location; with confirmed county location; valid

CASRN ; and valid concentrations. Disclosures that did not meet quality assurance criteria (132) or other, query

- specific criteria were excluded from analysis. A total of 880

disclosures (77% of 1,147 disclosures that met quality assurance criteria ) reported a total of 3,159 ingredient record s (8.1% of 39,099 ingredient record s) with information

indicating the data were confidential business information.

134Analysis of Da ta from FracFocus 1.0 March 2015

Table G

- 2. Twenty most frequently reported additive ingredients in Bradford County, Pen nsylvania, ranked by frequency of occurrence

.

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Hydrochloric acid 7647

- 01

- 0 458 (93%) 0.061 0.0059 0.63 539 (9.9%) 15 1.0 20

Methanol 67

- 56

- 1 374 (76%) 0.001 0.000034 0.011 570 (10%) 40 5.0 100

Propargyl alcohol 107

- 19

- 7 357 (73%) 0.000052 0.000000 * 0.00078 364 (6.7%) 10 1.0 40

Water 7732

- 18

- 5 321 (66%) 0.30 0.039 100 582 (11%) 85 40 99

Distillates, petroleum,

hydrotreated light 64742

- 47

- 8 232 (47%) 0.016 0.010 0.033 250 (4.6%) 30 27 40

Glutaraldehyde 111

- 30

- 8 200 (41%) 0.0073 0.0013 0.030 229 (4.2%) 27 5.0 30

Citric acid 77

- 92

- 9 172 (35%) 0.00083 0.00011 0.0099 172 (3.1%) 50 30 60

2,2

- Dibromo

- 3

- nitrilopropionamide 10222

- 01

- 2 144 (29%) 0.0046 0.0024 0.026 144 (2.6%) 10 10 100

2

- Butoxyethanol 111

- 76

- 2 138 (28%) 0.000080 0.000030 0.0027 138 (2.5%) 15 5.0 40

Ethanol 64

- 17

- 5 135 (28%) 0.0015 0.00034 0.0018 135 (2.5%) 5.0 1.0 5.0

Isopropanol 67

- 63

- 0 135 (28%) 0.00042 0.000015 0.0039 140 (2.6%) 35 5.0 60

Quaternary ammonium

compounds, benzyl

C12

- 16

- alkyldimethyl,

chlorides 68424

- 85

- 1 130 (27%) 0.0026 0.0015 0.0041 143 (2.6%) 7.0 5.5 10

Sodium hydroxide 1310

- 73

- 2 126 (26%) 0.000030 0.000010 0.011 136 (2.5%) 1.0 1.0 100

Sodium erythorbate 6381

- 77

- 7 124 (25%) 0.00028 0.00013 0.0043 125 (2.3%) 100 100 100

Polyethylene glycol 25322

- 68

- 3 117 (24%) 0.023 0.0080 0.039 117 (2.1%) 70 60 70

Acetic acid 64

- 19

- 7 100 (20%) 0.0011 0.00017 0.0021 100 (1.8%) 50 50 60

Didecyl dimethyl

ammonium chloride 7173

- 51

- 5 98 (20%) 0.0026 0.0021 0.0032 98 (1.8%) 8.0 8.0 10

Ethylene glycol 107

- 21

- 1 96 (20%) 0.0043 0.00025 0.018 132 (2.4%) 40 5.0 60

Ammonium chloride 12125

- 02

- 9 95 (19%) 0.0025 0.00070 0.0046 95 (1.7%) 5.0 1.5 10

Sodium sulfate 7757

- 82

- 6 86 (18%) 0.000040 0.000023 0.00010 86 (1.6%) 2.0 2.0 2.0

* Concentration is less than a millionth of a percentage by mass.

Note: Analysis considered 510 disclosures and 6,002 ingredient record s that met selected quality assurance criteria , including: completely parsed; unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; with confirmed state location; with confirmed county location; valid

CASRN ; and valid concentrations. Disclosures that did not meet quality assurance criteria (12) or other, query

- specific criteria were excluded from analysis. A total of 180

disclosures (35% of 513 disclosures that met quality assurance criteria ) reported a total of 448 ingredient record s (3.6% of 12,590 ingredient record s) with information

indicating the dat a were confidential business information.

135Analysis of Da ta from FracFocus 1.0 March 2015

Table G

- 3

. Twenty

- one most frequently reported additive ingredients in Dunn County, North Dakota , ranked by frequency of occurrence

.

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Potassium hydroxide 1310

- 58

- 3 231 (75%) 0.022 0.000000 * 0.051 235 (4.2%) 15 0.25 50

Guar gum 9000

- 30

- 0 213 (69%) 0.25 0.10 0.42 231 (4.1%) 60 1.6 100

Methanol 67

- 56

- 1 200 (65%) 0.025 0.0014 0.12 378 (6.8%) 30 0.36 100

Quartz 14808

- 60

- 7 185 (60%) 0.011 0.0000020 9.4 248 (4.4%) 5.0 0.20 69

Peroxydisulfuric acid,

diammonium salt 7727

- 54

- 0 184 (59%) 0.0037 0.000080 0.023 242 (4.3%) 100 0.016 100

Distillates, petroleum,

hydrotreated light 64742

- 47

- 8 176 (57%) 0.18 0.0037 0.43 238 (4.3%) 43 0.56 70

Solvent naphtha,

petroleum, heavy arom. 64742

- 94

- 5 136 (44%) 0.0047 0.000000 * 0.025 137 (2.4%) 5.0 0.028 30

Water 7732

- 18

- 5 136 (44%) 0.022 0.017 87 211 (3.8%) 80 30 100

Tetrakis(hydroxymethyl)

phosphonium sulfate 55566

- 30

- 8 127 (41%) 0.012 0.0021 0.016 130 (2.3%) 60 0.022 60

Sodium hydroxide 1310

- 73

- 2 106 (34%) 0.022 0.000000 * 0.093 115 (2.1%) 30 0.17 60

Carbonic acid,

dipotassium salt 584

- 08

- 7 102 (33%) 0.069 0.022 0.19 105 (1.9%) 60 48 60

Naphthalene 91

- 20

- 3 101 (33%) 0.0014 0.000000 * 0.0041 102 (1.8%) 5.0 0.0057 5.0

Formic acid, potassium

salt 590

- 29

- 4 100 (32%) 0.065 0.0084 0.12 100 (1.8%) 60 50 60

Diatomaceous earth,

calcined 91053

- 39

- 3 86 (28%) 0.024 0.0032 0.032 87 (1.6%) 100 100 100

Ethylene glycol 107

- 21

- 1 84 (27%) 0.037 0.0050 0.11 104 (1.9%) 30 0.70 100

Ethanol 64

- 17

- 5 78 (25%) 0.042 0.000000 * 0.062 82 (1.5%) 60 30 60

Boric acid 10043

- 35

- 3 77 (25%) 0.0028 0.00065 0.025 78 (1.4%) 30 15 100

Tetramethylammonium

chloride 75

- 57

- 0 76 (25%) 0.047 0.030 0.11 76 (1.4%) 0.43 0.28 60

Isopropanol 67

- 63

- 0 74 (24%) 0.026 0.00021 0.049 84 (1.5%) 30 0.18 60

Table continued on next page

136Analysis of Da ta from FracFocus 1.0 March 2015

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Nonyl phenol

ethoxylate 9016

- 45

- 9 73 (24%) 0.0039 0.0034 0.0092 73 (1.3%) 10 8.8 10

White mineral oil,

petroleum † 8042

- 47

- 5 73 (24%) 0.049 0.012 0.076 73 (1.3%) 100 91 100

* Concentration is less than a millionth of a percentage by mass.

† White mineral oil, petroleum is included as a 21st chemical because it had the same number of disclosures as nonyl phenol eth oxylate.

Note: Analysis considered 311 disclosures and 6,450 ingredient record s that met selected quality assurance criteria , including: completely parsed; unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; with confirmed state location; with confirmed county location; valid

CASRN; and valid concentrations. Disclosures that did not meet quality assurance criteria (35) or other, query

- specific criteria were excluded from analysis. A total of 258

disclosures (80% of 323 disclosure s that met quality assurance criteria ) reported a total of 1,435 ingredient record s (12% of 12,003 ingredient record s) with information

indicating the data were confidential business information.

137Analysis of Da ta from FracFocus 1.0 March 2015

Table G

- 4. Twenty most frequently reported additive ingredients in Garfield County, Colorado , ranked by frequency of occurrence

.

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum ingredient concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Ethanol 64

- 17

- 5 996 (86%) 0.025 0.00043 0.055 1,001 (6.4%) 60 5.0 60

Distillates, petroleum,

hydrotreated light 64742

- 47

- 8 932 (80%) 0.014 0.0059 0.022 934 (6.0%) 30 30 40

Methanol 67

- 56

- 1 830 (71%) 0.0045 0.0012 0.016 1,481 (9.5%) 30 5.0 70

Solvent naphtha,

petroleum, heavy

arom. 64742

- 94

- 5 770 (66%) 0.019 0.0010 0.027 1,101 (7.0%) 30 5.0 30

Sodium hypochlorite 7681

- 52

- 9 759 (65%) 0.023 0.0038 0.077 985 (6.3%) 30 13 100

Sodium hydroxide 1310

- 73

- 2 691 (59%) 0.0018 0.00096 0.0049 866 (5.5%) 2.0 2.0 5.0

Naphthalene 91

- 20

- 3 664 (57%) 0.0021 0.000030 0.0045 669 (4.3%) 5.0 1.0 5.0

Hydrochloric acid 7647

- 01

- 0 656 (56%) 0.037 0.010 0.078 659 (4.2%) 10 7.5 30

Sodium chloride 7647

- 14

- 5 651 (56%) 0.0059 0.000000 * 0.55 677 (4.3%) 10 1.0 100

1,2,4

- Trimethylbenzene 95

- 63

- 6 618 (53%) 0.00043 0.00027 0.00092 623 (4.0%) 1.0 1.0 1.0

Poly(oxy

- 1,2

- ethanediyl)

- nonylphenyl

- hydroxy

(mixture) 127087

- 87

- 0 617 (53%) 0.0022 0.0012 0.0085 622 (4.0%) 5.0 5.0 10

Isopropanol 67

- 63

- 0 493 (42%) 0.034 0.00011 0.044 810 (5.2%) 30 5.0 60

Acetic acid 64

- 19

- 7 397 (34%) 0.0018 0.00076 0.0028 397 (2.5%) 60 60 60

1

- Benzylquinolinium

chloride 15619

- 48

- 4 396 (34%) 0.000060 0.000028 0.000090 396 (2.5%) 10 10 10

Acetic anhydride 108

- 24

- 7 396 (34%) 0.0030 0.0013 0.0046 396 (2.5%) 100 100 100

Glutaraldehyde 111

- 30

- 8 393 (34%) 0.016 0.0066 0.016 393 (2.5%) 30 30 30

Didecyl dimethyl

ammonium chloride 7173

- 51

- 5 336 (29%) 0.0052 0.0026 0.0055 336 (2.1%) 10 10 10

Quaternary ammonium

compounds, benzyl

C12

- 16

- alkyldimethyl,

chlorides 68424

- 85

- 1 336 (29%) 0.0026 0.0013 0.0038 336 (2.1%) 5.0 5.0 7.0

Table continued on next page

138Analysis of Da ta from FracFocus 1.0 March 2015

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum ingredient concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

percentile Number (%)

of ingredient

records Median 5th

percentile 95th

percentile

Ammonium chloride 12125

- 02

- 9 331 (28%) 0.0031 0.0010 0.0074 359 (2.3%) 7.0 0.017 10

Water 7732

- 18

- 5 293 (25%) 0.050 0.0012 0.22 303 (1.9%) 100 60 100

* Concentration is less than a millionth of a percentage by mass.

Note: Analysis considered 1,166 disclosures and 17,337 ingredient record s that met selected quality assurance criteria , including: completely parsed; unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; with confirmed state location; with confirmed county location; valid

CASRN; and valid concentrations. Disclosures that did not meet quality assurance criteria (254) or other, query

- specific criteria were excluded from analysis. A total of 516

disclosures (44% of 1,169 disclosures that met quality assurance criteria ) reported a total of 1,493 ingredient record s (6.1% of 24,505 ingredient record s) with information

indicating the data were confidential business information.

139Analysis of Da ta from FracFocus 1.0 March 2015

Table G

- 5. Twenty most frequently reported additive ingredients in Kern County, California, ranked by frequency of occurrence

.

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

perc entile Numb er (%)

of ingredient

records Median 5th

percentile 95th

percentile

Guar gum 9000

- 30

- 0 511 (93%) 0.18 0.11 0.34 513 (5.1%) 60 0.74 60

Quartz 14808

- 60

- 7 486 (89%) 0.013 0.000010 27 979 (9.8%) 1.0 1.0 94

Water 7732

- 18

- 5 452 (83%) 0.055 0.034 80 508 (5.1%) 97 60 100

Peroxydisulfuric acid,

diammonium salt 7727

- 54

- 0 451 (82%) 0.0062 0.0033 0.051 462 (4.6%) 100 0.15 100

Diatomaceous earth,

calcined 91053

- 39

- 3 388 (71%) 0.012 0.00060 0.030 580 (5.8%) 60 60 100

Sodium hydroxide 1310

- 73

- 2 388 (71%) 0.0099 0.0062 0.016 391 (3.9%) 10 5.0 30

Hemicellulase Enzyme

Concentrate 9025

- 56

- 3 363 (66%) 0.0015 0.0010 0.0046 363 (3.6%) 3.0 3.0 3.0

2

- Methyl

- 3(2H)

-

isothiazolone 2682

- 20

- 4 360 (66%) 0.00011 0.000030 0.00027 360 (3.6%) 5.0 5.0 5.0

5

- Chloro

- 2

- methyl

3(2H)

- isothiazolone 26172

- 55

- 4 360 (66%) 0.00023 0.000060 0.00055 360 (3.6%) 10 10 10

Cristobalite 14464

- 46

- 1 360 (66%) 0.000020 0.000010 0.000060 360 (3.6%) 1.0 1.0 1.0

Magnesium chloride 7786

- 30

- 3 360 (66%) 0.00011 0.000030 0.00027 360 (3.6%) 5.0 5.0 5.0

Magnesium nitrate 10377

- 60

- 3 360 (66%) 0.00023 0.000060 0.00054 360 (3.6%) 10 10 10

Boron sodium oxide 1330

- 43

- 4 352 (64%) 0.029 0.020 0.045 352 (3.5%) 30 10 30

Ethylene glycol 107

- 21

- 1 349 (64%) 0.029 0.014 0.045 349 (3.5%) 30 30 30

1,2

- Ethanediaminium,

N, N'

- bis[2

- [bis(2

- hydroxyethyl)

methylammonio]

ethyl]

- N,N'bis (2

- hydroxyethyl)

- N,N'

- dimethyl

- ,tetrachloride 138879

- 94

- 4 339 (62%) 0.055 0.043 0.075 343 (3.4%) 60 60 60

Distillates, petroleum,

hydrotreated light 64742

- 47

- 8 316 (58%) 0.079 0.052 0.16 318 (3.2%) 30 30 30

1

- Butoxy

- 2

- propanol 5131

- 66

- 8 311 (57%) 0.013 0.0088 0.026 311 (3.1%) 5.0 5.0 5.0

Distillates, petroleum,

hydrotreated light

paraffinic 64742

- 55

- 8 310 (57%) 0.080 0.054 0.16 310 (3.1%) 30 30 30

Table continued on next page

140Analysis of Da ta from FracFocus 1.0 March 2015

EPA

- standardized

chemical name CASRN Maximum concentration in hydraulic fracturing fluid

(% by mass) Maximum concentration in additive

(% by mass)

Number (%) of

disclosures Median 5th

percentile 95th

perc entile Numb er (%)

of ingredient

records Median 5th

percentile 95th

percentile

Isotridecanol,

ethoxylated 9043

- 30

- 5 308 (56%) 0.013 0.0090 0.026 308 (3.1%) 5.0 5.0 5.0

Phosphonic acid 13598

- 36

- 2 220 (40%) 0.00021 0.000090 0.00033 220 (2.2%) 1.0 1.0 1.0

Note: Analysis considered 547 disclosures and 10,997 ingredient record s that met selected quality assurance criteria , i ncluding: completely parsed; unique combin ation of

fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; with confirmed state location; with confirmed county location; valid

CASRN ; and valid concentrations. Disclosures that did not meet quality assurance criteria (153) or other, query

- specific criteria were excluded from analysis. A total of 523

disclosures (79% of 666 disclosures that met quality assurance criteria ) reported a total of 767 ingredient record s (3.9% of 19,854 ingredient record s) with information

indicating the data were confidential business information.

141Analysis of Data from FracFocus 1.0 March 2015



# Appendix H. Total Water Volumes by County

Table H

- 1. Total w ater volumes, summarized by county

.

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Colorado Weld 3,011 2,335,336,985 407,442 128,100 2,977,508

Colorado Garfield 1,355 3,624,211,889 1,707,024 695,047 8,093,060

Texas Andrews 1,171 518,991,576 91,697 29,631 1,429,964

Texas County

Uncertain 1,049 2,441,366,185 1,306,225 25,241 6,868,724

Texas Glasscock 935 1,241,568,473 981,372 569,677 2,662,435

Utah Uintah 835 326,559,958 340,715 81,509 804,497

Texas Martin 823 937,501,845 1,099,924 494,534 1,705,162

Texas Ector 822 497,360,705 209,209 40,444 1,886,442

Texas Upton 777 974,777,378 1,216,685 30,060 1,924,754

Texas Tarrant 747 2,968,194,610 3,678,696 1,324,407 7,575,669

Texas Dimmit 715 3,938,854,414 5,322,954 3,076,202 8,709,221

California Kern 677 89,129,306 77,238 19,135 328,606

Texas Karnes 595 2,254,998,809 3,514,377 2,148,427 6,484,902

Texas La Salle 568 2,683,074,962 4,488,267 2,684,300 7,498,348

Texas Midland 530 654,029,168 1,254,809 455,722 1,892,398

North Dakota Mountrail 520 916,997,966 1,558,022 707,235 3,357,661

Pennsylvania Bradford 513 2,168,115,265 4,350,571 213,158 7,181,555

Utah Duchesne 501 183,472,997 129,079 18,228 1,297,842

North Dakota McKenzie 483 1,241,789,756 2,433,648 784,762 4,216,218

Wyoming Sublette 474 629,569,835 1,099,287 675,704 3,464,024

Louisiana De Soto 457 2,233,883,199 4,796,568 2,851,654 7,677,568

Texas Reagan 450 885,418,227 1,145,983 414,863 8,962,874

New Mexico Eddy 442 475,792,263 566,934 60,256 3,590,099

Texas Webb 439 2,294,331,122 4,983,952 1,228,471 11,178,023

North Dakota Williams 430 1,163,067,734 2,390,827 907,390 5,878,448

Arkansas Van Buren 401 1,816,523,710 4,341,724 2,455,755 7,247,129

Texas McMullen 384 1,641,511,084 3,933,824 210,720 8,545,215

Texas Montague 375 1,958,947,601 5,137,420 3,286,042 7,334,297

Pennsylvania Lycoming 361 1,498,219,767 3,877,797 1,597,625 7,475,978

Texas Ward 345 227,837,517 246,085 7,795 2,156,625

Texas Gonzales 344 1,253,423,805 3,632,223 1,890,399 5,892,711

North Dakota Dunn 331 630,097,859 2,017,621 409,803 3,361,183

Pennsylvania Susquehanna 327 1,546,179,194 4,798,290 940,909 7,816,150

Wyoming Sweetwater 321 84,850,331 229,974 79,090 435,011

Texas DeWitt 320 1,104,210,329 3,426,088 2,028,110 4,790,741

Table continued on next page

142Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Arkansas White 309 1,749,005,205 5,782,854 3,655,427 7,416,763

Arkansas Conway 302 1,596,170,693 5,266,774 2,919,365 7,957,921

Texas Gaines 298 44,087,004 79,411 18,330 269,241

Texas Wise 291 1,157,129,977 3,875,046 918,692 7,969,196

Texas Johnson 289 1,190,791,843 3,969,422 1,754,012 7,202,405

New Mexico Lea 286 244,252,238 183,645 53,235 3,730,169

Pennsylvania Tioga 286 1,132,668,079 3,598,474 2,285,636 6,572,202

Texas Howard 286 219,523,127 895,986 26,018 1,523,373

Texas Irion 284 945,564,352 895,468 45,494 11,729,639

Texas Wheeler 283 1,773,621,591 6,292,608 879,360 12,398,544

Texas Mitchell 278 22,018,458 30,402 14,154 88,003

Arkansas Cleburne 263 1,489,329,655 5,974,108 3,401,011 7,538,336

Texas Denton 263 934,748,202 1,836,744 1,014,405 9,008,399

Texas Reeves 263 352,616,549 1,081,442 104,447 3,865,365

Texas Milam 254 9,844,030 16,000 16,000 18,900

Texas Crane 245 196,718,764 175,308 26,277 2,794,840

Wyoming Natrona 226 3,663,585 5,648 5,032 7,685

Pennsylvania Washington 223 867,457,663 3,358,519 2,553,790 7,031,557

Oklahoma Alfalfa 199 385,043,193 1,865,304 1,266,922 2,923,830

Texas Yoakum 190 16,252,142 65,966 26,097 138,354

New Mexico San Juan 188 24,032,553 72,200 19,998 476,978

Texas Live Oak 182 612,387,421 3,334,502 1,992,043 4,466,792

Texas Cooke 178 930,155,506 5,361,300 1,791,556 7,915,538

Oklahoma Roger Mills 177 490,227,227 2,488,248 662,273 4,991,475

New Mexico Rio Arriba 174 33,138,782 114,732 24,531 452,176

Oklahoma Woods 166 327,924,769 1,916,477 1,306,536 2,664,942

Oklahoma Ellis 165 398,559,056 2,301,505 732,749 4,023,155

State

Uncertain County

Uncertain 158 488,083,669 2,770,090 80,067 6,945,958

Oklahoma Canadian 158 966,487,571 6,340,910 3,045,404 8,472,344

Pennsylvania Greene 157 781,556,032 4,305,363 2,433,957 10,493,381

Texas Loving 155 282,297,269 1,517,208 56,095 4,341,797

Louisiana Red River 153 1,139,265,130 7,179,763 4,293,341 11,653,648

Colorado Las Animas 146 15,768,503 95,974 20,424 260,255

Texas Parker 144 554,945,907 3,665,336 1,340,232 7,112,669

Colorado Rio Blanco 143 294,677,269 2,248,291 96,911 3,232,073

Texas Panola 143 696,572,353 3,804,948 26,987 14,494,738

Texas Atascosa 137 694,264,027 4,089,792 2,289,300 9,904,570

Texas Hemphill 136 549,108,685 3,059,675 460,143 7,574,170

Table continued on next page

143Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

North Dakota Divide 133 212,401,131 1,580,796 678,912 2,536,918

Louisiana Sabine 129 790,459,623 6,424,656 3,557,957 9,120,145

North Dakota County

Uncertain 126 274,188,475 1,986,598 376,173 3,555,922

Oklahoma County

Uncertain 115 354,593,378 1,654,044 16,796 9,930,348

Texas Freestone 113 108,863,226 784,482 151,016 2,485,651

Texas Crockett 107 596,159,001 6,882,549 64,223 10,739,690

Arkansas Faulkner 106 567,953,587 5,289,045 3,204,945 8,067,928

Oklahoma Pittsburg 106 756,599,235 6,939,435 3,607,478 11,799,127

Montana Richland 104 173,612,043 1,604,648 359,501 3,211,767

Wyoming Converse 98 230,123,849 2,303,838 866,463 4,693,910

Oklahoma Washita 95 215,800,796 2,510,928 320,170 3,201,844

Texas Lipscomb 92 182,722,458 1,482,313 312,653 4,038,008

Oklahoma Grant 89 165,254,145 1,792,535 1,490,734 2,219,473

Pennsylvania Westmoreland 89 413,919,647 4,382,954 2,602,314 7,766,369

Texas Nacogdoches 89 543,371,967 6,478,122 190,003 10,899,353

Wyoming Fremont 85 56,372,038 273,651 13,706 1,875,955

Oklahoma Dewey 82 331,068,664 3,774,240 790,768 6,455,102

Louisiana Caddo 80 311,083,907 4,010,916 167,521 6,956,650

Oklahoma Blaine 79 414,164,933 5,109,410 2,743,823 8,789,371

Ohio Carroll 78 334,774,734 4,104,765 3,127,692 5,738,399

Texas Robertson 75 92,251,731 739,196 148,897 3,382,029

Texas Ochiltree 71 71,885,269 852,457 358,029 2,179,675

Texas Schleicher 69 54,035,392 93,282 23,663 4,415,300

North Dakota Burke 68 130,039,568 2,181,879 92,238 2,916,078

North Dakota Stark 67 97,818,062 1,485,580 687,725 1,903,938

Louisiana County

Uncertain 65 417,334,020 6,099,364 2,141,777 12,166,446

Pennsylvania Fayette 65 243,844,255 3,614,704 1,982,122 5,899,561

Texas Frio 61 256,406,734 4,248,636 1,424,183 6,901,482

Texas Jack 61 36,154,895 414,918 25,200 2,594,283

Utah Carbon 60 14,656,123 234,643 122,492 363,483

Oklahoma Beckham 59 221,343,112 3,231,150 87,765 8,214,126

Pennsylvania Wyoming 59 319,383,314 5,360,166 1,131,136 9,250,744

Louisiana Bienville 56 217,714,155 4,514,531 86,517 6,986,721

Texas Roberts 56 80,958,031 1,203,233 40,661 3,316,569

Wyoming Park 56 1,802,669 28,412 15,488 41,300

Texas Hidalgo 55 17,112,033 287,654 77,524 647,891

Table continued on next page

144Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Oklahoma Grady 54 253,307,556 4,864,995 73,199 7,757,636

Pennsylvania Butler 53 256,960,489 4,748,310 3,075,507 7,167,812

Texas San Augustine 53 364,221,026 6,307,110 1,748,771 12,199,824

Texas Crosby 51 2,808,045 58,296 36,905 78,430

Montana Roosevelt 50 110,068,800 2,427,634 860,538 3,227,131

Pennsylvania Clearfield 50 222,985,275 4,219,803 2,721,829 7,109,046

Texas Zavala 50 273,942,903 6,147,960 3,163,445 7,218,131

Texas Harrison 49 293,540,779 5,717,723 875,642 10,451,956

Oklahoma Carter 48 340,585,434 8,224,986 37,298 8,983,229

Wyoming Carbon 48 8,909,624 182,173 70,660 285,534

North Dakota Billings 47 88,868,499 2,149,224 732,783 2,819,213

Texas Hood 47 163,449,153 3,402,126 1,926,744 5,561,762

Pennsylvania Armstrong 46 126,190,783 171,396 101,966 6,931,090

Texas Wilson 46 174,790,616 3,822,813 1,434,854 5,635,023

West Virginia Ohio 45 245,169,636 5,509,812 3,406,789 7,881,980

Pennsylvania Clinton 44 188,730,732 4,257,620 2,798,770 5,723,557

Texas Dawson 44 42,668,983 1,133,139 43,394 1,457,678

Louisiana Bossier 42 220,225,439 5,269,992 92,427 8,328,128

Texas Winkler 42 15,930,828 103,501 12,115 1,638,809

Wyoming County

Uncertain 41 6,508,970 129,640 6,550 305,735

Colorado Larimer 40 10,832,123 224,906 71,698 470,367

Colorado La Plata 39 6,967,007 196,744 36,136 227,087

Texas Madison 39 99,968,464 2,378,670 431,446 4,848,839

Texas Stephens 39 5,270,482 71,484 6,002 214,294

Pennsylvania Sullivan 38 140,540,343 4,009,971 943,893 5,851,066

Texas Leon 38 112,445,340 2,709,214 165,049 7,517,538

Texas Starr 37 10,683,140 255,412 58,081 531,802

Alaska North Slope (the

borough of) 37 13,150,891 88,448 36,437 435,638

Texas Borden 36 15,968,027 111,756 22,427 1,357,392

Virginia Buchanan 36 1,267,707 33,243 20,559 52,605

West Virginia Marshall 36 168,954,993 4,596,144 3,217,379 6,367,568

Alabama Jefferson 35 1,157,495 33,335 22,668 40,846

Texas Shelby 35 277,531,622 6,327,720 88,089 17,230,326

Texas Sterling 35 86,577,074 345,374 160,584 10,062,476

Virginia Dickenson 34 1,562,380 37,430 16,865 113,089

West Virginia Doddridge 34 180,858,468 5,281,962 2,200,764 7,939,842

Texas Culberson 32 83,961,631 2,515,323 40,181 5,496,785

Table continued on next page

145Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Montana Sheridan 31 21,734,049 410,690 236,019 1,712,485

Oklahoma Noble 31 67,438,727 2,166,133 854,988 3,423,273

West Virginia Marion 31 140,220,776 4,718,028 2,231,481 6,620,712

Oklahoma Coal 30 180,062,029 4,824,002 246,744 11,560,111

Texas Kleberg 30 7,048,508 223,965 49,495 488,846

Texas Medina 30 505,485 17,031 14,868 19,099

Texas Pecos 30 16,588,529 139,020 61,410 1,960,109

Texas Rusk 30 141,023,149 4,837,499 29,078 9,800,251

Kansas Comanche 29 53,072,084 1,796,122 1,064,162 2,616,347

New Mexico Colfax 29 1,470,173 38,640 1,054 113,820

Oklahoma Marshall 29 221,714,808 8,006,838 5,420,209 9,310,417

Texas Terry 29 14,987,507 173,754 30,441 3,220,820

West Virginia Wetzel 29 156,461,105 5,288,881 3,922,061 7,170,799

Arkansas Independence 28 160,687,548 5,588,037 4,208,795 7,447,169

Oklahoma Beaver 28 58,081,436 2,328,146 109,363 2,960,234

Wyoming Campbell 28 27,762,544 964,350 166,791 2,092,830

Texas Lavaca 27 103,054,135 4,329,321 39,991 6,242,700

Texas Scurry 27 6,853,945 41,118 19,265 493,856

Colorado County

Uncertain 26 45,171,994 2,118,956 122,484 3,175,880

Texas Stonewall 26 1,785,353 38,391 17,042 198,744

West Virginia Brooke 26 109,537,029 4,222,596 3,128,344 5,722,616

Texas Brooks 25 3,179,142 93,450 42,428 326,259

Texas Wilbarger 25 345,979 14,791 4,368 21,216

Colorado Broomfield 24 9,046,089 397,068 295,096 421,458

Colorado Yuma 24 733,530 29,673 25,626 36,582

Colorado Boulder 23 8,258,548 410,424 129,738 422,881

Kansas Harper 23 36,664,604 1,839,936 47,855 2,551,977

Ohio Columbiana 23 69,107,766 3,213,420 1,709,912 3,850,190

Pennsylvania McKean 23 120,961,008 5,758,704 456,830 8,030,157

Texas Hockley 23 6,058,250 27,578 19,971 274,995

Wyoming Laramie 23 36,626,308 1,561,077 77,990 3,326,760

Oklahoma Stephens 22 63,381,549 1,664,689 38,529 7,941,127

Pennsylvania County

Uncertain 22 84,860,930 4,219,781 984,400 5,973,536

Texas Wichita 22 305,152 11,290 2,564 25,568

Arkansas County

Uncertain 21 114,187,387 5,816,748 3,386,662 6,923,322

New Mexico Harding 21 219,163 6,048 4,662 8,694

Table continued on next page

146Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Alabama Tuscaloosa 20 907,701 45,255 35,353 57,480

Texas Limestone 20 21,484,098 645,913 163,792 3,583,703

Colorado Mesa 19 244,114,104 14,542,836 444,333 22,609,230

North Dakota Mclean 19 24,325,679 1,177,851 675,033 1,958,939

Oklahoma Caddo 19 50,903,859 3,955,052 41,756 5,098,028

West Virginia Taylor 19 105,771,236 5,849,046 3,646,583 7,669,007

Colorado Adams 18 6,504,057 211,902 46,661 880,173

Louisiana Beauregard 18 4,763,121 225,936 62,555 532,135

Oklahoma Harper 17 17,614,411 1,266,798 23,226 1,713,123

West Virginia Upshur 17 69,820,643 4,081,094 643,516 7,880,985

Ohio Jefferson 16 66,343,492 4,257,225 2,942,478 5,471,193

Oklahoma Kay 16 42,971,113 2,746,611 1,411,278 3,847,714

Pennsylvania Beaver 16 64,700,812 3,677,835 309,456 8,591,746

Texas Maverick 16 104,761,837 7,381,269 2,363,809 9,588,600

Texas San Patricio 16 2,120,580 70,539 23,457 369,348

West Virginia Harrison 16 98,359,628 5,923,491 4,334,106 8,748,747

California Sutter 15 373,086 20,622 12,046 40,900

Colorado Phillips 15 346,374 23,100 22,890 23,264

Pennsylvania Centre 15 76,929,372 5,663,806 2,431,605 6,406,011

Texas Cochran 15 5,959,787 316,176 20,152 827,270

Texas Palo Pinto 15 20,579,492 620,510 139,033 3,155,617

Utah County

Uncertain 15 9,138,125 772,448 79,276 1,134,760

Kansas Barber 14 19,858,588 1,436,880 212,300 2,260,322

Kansas Haskell 14 205,387 12,306 8,620 24,215

New Mexico County

Uncertain 14 2,351,840 61,383 21,544 624,674

Oklahoma Custer 14 38,094,335 2,510,865 1,119,405 4,325,305

Oklahoma Pawnee 14 31,321,465 2,317,287 1,375,338 2,850,122

Pennsylvania Elk 14 74,994,059 5,337,218 3,910,733 6,608,196

Texas Oldham 14 2,752,335 195,751 99,457 338,459

Texas Zapata 14 2,344,265 168,845 43,197 374,312

Kansas County

Uncertain 13 7,730,168 104,971 12,029 2,031,354

Texas Bee 13 39,984,197 3,413,242 1,278,998 4,225,536

Texas Houston 13 23,865,860 1,743,168 599,830 3,109,102

Wyoming Hot Springs 13 537,703 41,948 34,372 46,919

California Ventura 12 3,597,475 350,642 48,682 518,445

Colorado Moffat 12 29,096,450 138,711 22,841 13,201,470

Table continued on next page

147Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Montana Glacier 12 10,241,652 950,581 46,805 1,589,657

Ohio Harrison 12 50,031,353 4,058,040 3,447,473 5,102,299

Texas Grayson 12 18,556,255 515,193 5,678 4,773,123

Kansas Finney 11 4,835,816 13,188 10,059 2,333,068

Pennsylvania Lawrence 11 53,944,488 4,144,434 2,668,953 10,003,861

Texas Fayette 11 27,381,679 2,297,402 482,811 4,430,664

Texas Hutchinson 11 630,263 55,772 40,469 79,461

Texas Nolan 11 9,094,250 65,600 15,701 4,334,946

Wyoming Lincoln 11 1,546,099 132,976 107,553 194,334

Arkansas Logan 10 4,767,333 185,451 31,370 1,302,000

Oklahoma Hughes 10 61,080,038 6,028,764 4,663,997 7,603,304

Oklahoma Johnston 10 74,444,034 7,866,033 5,653,253 8,375,373

Pennsylvania Indiana 10 32,371,373 3,323,237 1,051,461 5,060,509

Texas Fisher 10 11,899,478 64,416 31,895 5,949,028

Texas Hansford 10 5,769,487 85,920 9,824 2,437,602

Texas Sutton 10 3,130,092 88,452 26,678 1,418,926

Oklahoma Latimer 9 1,190,337 132,750 58,479 245,112

Pennsylvania Allegheny 9 27,247,149 2,834,574 2,389,479 4,223,652

Pennsylvania Potter 9 32,966,493 4,210,510 2,386,660 4,603,434

Texas Sabine 9 62,217,624 6,447,042 5,435,480 9,144,929

Utah San Juan 9 510,880 54,739 25,469 104,540

Wyoming Uinta 9 1,172,285 137,313 103,664 153,696

Texas Archer 8 308,847 21,653 1,000 119,221

Texas Brazos 8 25,800,462 2,731,726 781,841 5,760,135

Texas Coke 8 11,989,003 91,686 37,289 7,450,787

Texas Gregg 8 18,754,840 2,230,473 186,877 4,466,825

Texas Montgomery 8 471,869 58,611 45,614 75,174

California County

Uncertain 7 808,494 106,176 70,897 168,278

Oklahoma Garvin 7 34,777,900 4,801,914 3,734,442 6,484,745

Oklahoma Kingfisher 7 26,868,858 3,046,680 1,871,734 6,396,409

Texas Erath 7 1,682,982 270,186 101,039 329,339

Texas Grimes 7 30,986,483 2,703,960 1,745,520 12,057,746

Virginia Wise 7 190,722 29,946 9,043 39,421

West Virginia Barbour 7 39,824,792 5,299,900 2,721,541 8,103,067

Colorado Morgan 6 7,705,597 21,766 18,462 4,144,234

Colorado San Miguel 6 570,386 88,618 24,107 179,672

Kansas Morton 6 78,104 11,424 7,709 22,457

Louisiana Natchitoches 6 25,340,370 4,163,259 1,517,208 6,944,319

Table continued on next page

148Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Louisiana Webster 6 2,317,926 273,395 54,306 840,096

Montana County

Uncertain 6 11,894,148 2,515,023 225,288 3,028,253

Montana Rosebud 6 7,027,827 1,072,667 836,642 1,763,954

North Dakota Golden Valley 6 9,148,766 1,514,858 1,123,363 1,980,707

Oklahoma Bryan 6 20,568,752 2,242,258 122,955 8,047,494

Oklahoma Logan 6 8,439,674 498,015 43,493 3,690,810

Oklahoma Major 6 2,389,800 356,034 215,492 667,853

Texas Newton 6 625,073 77,241 62,387 211,680

Texas Orange 6 684,146 105,385 88,559 167,470

Wyoming Big Horn 6 5,765,641 55,162 12,381 2,953,715

Wyoming Goshen 6 11,555,075 2,000,185 285,903 3,526,013

Colorado Jackson 5 1,915,902 326,830 61,733 663,932

North Dakota Bottineau 5 479,974 97,744 83,732 108,279

Pennsylvania Jefferson 5 27,574,346 5,302,920 4,801,747 6,469,091

Texas Burleson 5 6,071,020 1,154,644 1,054,014 1,522,626

Texas Haskell 5 169,100 32,394 7,115 60,191

Texas Potter 5 855,385 176,538 123,606 210,865

Texas Runnels 5 68,082 6,930 5,888 31,542

Texas Washington 5 5,307,569 936,726 336,941 1,930,527

Michigan Gladwin 4 2,157,052 360,827 14,730 1,313,607

Michigan Kalkaska 4 47,996,702 10,511,866 6,250,906 19,829,679

Michigan Missaukee 4 87,660 21,971 18,272 25,480

Oklahoma Le Flore 4 513,318 128,066 98,134 158,894

Oklahoma Oklahoma 4 2,317,560 463,008 462,126 859,589

Oklahoma Payne 4 19,797,691 4,734,292 3,989,483 6,210,545

Oklahoma Texas 4 149,766 22,302 7,256 88,822

Texas Austin 4 4,159,098 1,163,621 147,045 1,759,120

Texas Hardeman 4 716,148 215,661 60,175 246,626

Texas Kent 4 899,295 19,326 10,983 726,362

Texas Lynn 4 2,278,945 415,474 97,330 1,258,110

West Virginia County

Uncertain 4 19,386,108 4,514,832 3,182,953 6,974,474

California Colusa 3 61,614 15,162 13,612 31,227

California Los Angeles 3 437,350 143,892 127,112 165,778

Colorado Arapahoe 3 7,947,553 2,580,173 2,430,678 2,915,999

Colorado Delta 3 1,071,931 490,320 109,451 512,063

Kansas Clark 3 1,557,336 45,864 44,730 1,324,768

Kansas Gray 3 6,518,606 2,227,926 1,882,288 2,424,909

Table continued on next page

149Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Kansas Hodgeman 3 5,475,838 1,839,978 1,790,202 1,850,068

Louisiana East Feliciana 3 7,323,225 3,087,995 536,804 3,892,502

Louisiana Union 3 9,721,910 180,586 74,089 8,549,220

Mississippi Amite 3 28,706,118 11,916,618 4,746,676 12,747,197

New Mexico Chaves 3 5,558,331 1,772,439 1,406,084 2,355,707

Ohio Guernsey 3 16,806,622 5,205,007 3,182,721 8,299,734

Oklahoma Osage 3 7,680,204 2,847,348 1,476,002 3,443,038

Pennsylvania Blair 3 11,814,180 3,628,968 3,551,365 4,541,120

Pennsylvania Clarion 3 16,245,996 5,128,302 4,612,694 6,418,891

Pennsylvania Forest 3 15,439,662 4,062,366 4,040,555 7,011,484

Pennsylvania Somerset 3 11,510,817 2,978,576 2,710,144 5,564,588

Texas Dallas 3 11,267,802 3,716,580 3,716,315 3,823,100

Texas Garza 3 1,175,632 27,174 23,772 1,015,275

Texas Kenedy 3 487,536 128,478 65,125 283,723

Texas Nueces 3 2,001,377 141,690 104,748 1,597,309

Texas Polk 3 388,072 115,786 115,113 153,102

Texas Somervell 3 9,651,992 3,283,022 3,068,408 3,320,269

Texas Van Zandt 3 275,610 93,626 88,362 94,149

Texas Walker 3 6,757,968 1,766,352 621,163 4,224,562

West Virginia Preston 3 16,839,606 5,566,722 5,552,471 5,706,469

Arkansas Sebastian 2 1,257,652 628,826 194,392 1,063,260

Colorado Fremont 2 1,178,755 589,378 63,886 1,114,869

Kansas Grant 2 308,196 154,098 152,359 155,837

Kansas Ness 2 3,291,918 1,645,959 1,304,682 1,987,236

Kansas Seward 2 27,782 13,891 13,258 14,524

Kansas Stanton 2 21,672 10,836 10,685 10,987

Louisiana Calcasieu 2 140,231 70,116 40,572 99,659

Louisiana Jackson 2 31,731 15,866 3,365 28,366

Louisiana Lincoln 2 6,627,470 3,313,735 2,375,712 4,251,758

Montana Daniels 2 1,280,951 640,476 403,146 877,805

Ohio Noble 2 16,634,545 8,317,273 7,767,089 8,867,456

Ohio Tuscarawas 2 13,470,465 6,735,233 5,553,163 7,917,302

Oklahoma McClain 2 4,133,534 2,066,767 1,033,703 3,099,831

Pennsylvania Cameron 2 13,246,674 6,623,337 5,046,907 8,199,767

Pennsylvania Columbia 2 11,253,084 5,626,542 4,225,750 7,027,334

Pennsylvania Venango 2 4,885,144 2,442,572 577,880 4,307,264

Pennsylvania Warren 2 4,694,917 2,347,459 296,766 4,398,151

Texas Ellis 2 8,320,032 4,160,016 3,673,341 4,646,691

Table continued on next page

150Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Texas Hardin 2 245,322 122,661 95,993 149,329

Texas Hartley 2 3,889,590 1,944,795 263,049 3,626,541

Texas Jim Hogg 2 252,728 126,364 69,028 183,700

Texas King 2 19,278 9,639 9,545 9,734

Texas Lee 2 2,338,433 1,169,217 1,111,741 1,226,692

Texas Marion 2 11,877,776 5,938,888 5,684,831 6,192,945

Texas Smith 2 413,170 206,585 154,079 259,091

Texas Terrell 2 221,625 110,813 103,115 118,510

Texas Upshur 2 462,828 231,414 114,818 348,010

Texas Waller 2 229,891 114,946 106,473 123,418

Texas Wharton 2 90,173 45,087 35,202 54,971

Texas Willacy 2 220,164 110,082 84,000 136,164

Texas Wood 2 345,995 172,998 58,585 287,410

Texas Young 2 136,836 68,418 11,605 125,231

West Virginia Monongalia 2 13,665,036 6,832,518 6,545,503 7,119,533

West Virginia Ritchie 2 12,994,464 6,497,232 5,775,554 7,218,910

West Virginia Webster 2 4,504,584 2,252,292 2,246,017 2,258,567

Wyoming Niobrara 2 194,418 97,209 92,012 102,407

Arkansas Franklin 1 6,384 6,384 6,384 6,384

Arkansas Yell 1 29,946 29,946 29,946 29,946

California Glenn 1 31,752 31,752 31,752 31,752

Colorado Dolores 1 107,969 107,969 107,969 107,969

Colorado Elbert 1 39,215 39,215 39,215 39,215

Colorado El Paso 1 55,019 55,019 55,019 55,019

Colorado Routt 1 142,372 142,372 142,372 142,372

Kansas Ford 1 1,797,019 1,797,019 1,797,019 1,797,019

Kansas Kearny 1 18,942 18,942 18,942 18,942

Kansas Lane 1 1,645,896 1,645,896 1,645,896 1,645,896

Kansas Meade 1 20,286 20,286 20,286 20,286

Kansas Sheridan 1 1,474,872 1,474,872 1,474,872 1,474,872

Kansas Stevens 1 124,291 124,291 124,291 124,291

Kansas Sumner 1 455,532 455,532 455,532 455,532

Louisiana Allen 1 172,116 172,116 172,116 172,116

Louisiana Caldwell 1 40,110 40,110 40,110 40,110

Louisiana Claiborne 1 7,603,184 7,603,184 7,603,184 7,603,184

Louisiana Rapides 1 3,388,095 3,388,095 3,388,095 3,388,095

Louisiana Tangipahoa 1 3,823,858 3,823,858 3,823,858 3,823,858

Louisiana West Feliciana 1 4,605,619 4,605,619 4,605,619 4,605,619

Table continued on next page

151Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Louisiana Winn 1 2,150,872 2,150,872 2,150,872 2,150,872

Michigan Cheboygan 1 33,306 33,306 33,306 33,306

Michigan Ogemaw 1 20,701 20,701 20,701 20,701

Michigan Roscommon 1 4,804,620 4,804,620 4,804,620 4,804,620

Mississippi Wilkinson 1 6,430,629 6,430,629 6,430,629 6,430,629

Montana Garfield 1 927,438 927,438 927,438 927,438

Montana Musselshell 1 713,908 713,908 713,908 713,908

New Mexico Roosevelt 1 79,212 79,212 79,212 79,212

New Mexico Sandoval 1 792,616 792,616 792,616 792,616

Ohio Ashland 1 2,932,422 2,932,422 2,932,422 2,932,422

Ohio Belmont 1 3,778,068 3,778,068 3,778,068 3,778,068

Ohio Coshocton 1 10,816,646 10,816,646 10,816,646 10,816,646

Ohio Knox 1 2,204,454 2,204,454 2,204,454 2,204,454

Ohio Medina 1 2,572,682 2,572,682 2,572,682 2,572,682

Ohio Muskingum 1 10,170,198 10,170,198 10,170,198 10,170,198

Ohio Portage 1 6,415,458 6,415,458 6,415,458 6,415,458

Ohio Stark 1 4,752,384 4,752,384 4,752,384 4,752,384

Ohio Summit 1 94,537 94,537 94,537 94,537

Ohio Wayne 1 3,309,559 3,309,559 3,309,559 3,309,559

Oklahoma Jefferson 1 4,620 4,620 4,620 4,620

Oklahoma Kiowa 1 216,871 216,871 216,871 216,871

Oklahoma Love 1 8,708,742 8,708,742 8,708,742 8,708,742

Oklahoma Seminole 1 187,740 187,740 187,740 187,740

Pennsylvania Crawford 1 4,803,563 4,803,563 4,803,563 4,803,563

Pennsylvania Huntingdon 1 5,325,418 5,325,418 5,325,418 5,325,418

Texas Angelina 1 1,542,275 1,542,275 1,542,275 1,542,275

Texas Bosque 1 1,444,143 1,444,143 1,444,143 1,444,143

Texas Cherokee 1 1,025,574 1,025,574 1,025,574 1,025,574

Texas Clay 1 25,536 25,536 25,536 25,536

Texas Colorado 1 104,244 104,244 104,244 104,244

Texas Concho 1 29,946 29,946 29,946 29,946

Texas Cottle 1 671,286 671,286 671,286 671,286

Texas Edwards 1 91,350 91,350 91,350 91,350

Texas Franklin 1 13,524 13,524 13,524 13,524

Texas Goliad 1 44,226 44,226 44,226 44,226

Texas Jefferson 1 77,291 77,291 77,291 77,291

Texas Jones 1 56,667 56,667 56,667 56,667

Texas Knox 1 17,178 17,178 17,178 17,178

Table continued on next page

152Analysis of Data from FracFocus 1.0 March 2015

State County Number of

disclosures Cumulative

total water

volume

(gallons) Total w ater volume per disclosure

(gallons)

Median 5 th

percentile 95 th

percentile

Texas Liberty 1 58,668 58,668 58,668 58,668

Texas Menard 1 15,708 15,708 15,708 15,708

Texas Moore 1 37,026 37,026 37,026 37,026

Texas Navarro 1 9,606,805 9,606,805 9,606,805 9,606,805

Texas Sherman 1 67,171 67,171 67,171 67,171

Texas Tyler 1 216,174 216,174 216,174 216,174

Utah Sevier 1 77,859 77,859 77,859 77,859

West Virginia Hancock 1 2,420,124 2,420,124 2,420,124 2,420,124

West Virginia Lewis 1 4,737,978 4,737,978 4,737,978 4,737,978

West Virginia Pleasants 1 32,340 32,340 32,340 32,340

West Virginia Tyler 1 4,168,710 4,168,710 4,168,710 4,168,710

Wyoming Johnson 1 68,250 68,250 68,250 68,250

Wyoming Washakie 1 2,146,866 2,146,866 2,146,866 2,146,866

Entire Dataset 37,796 91,805,425,640 1,508,724 29,526 7,196,702

Note: Analysis considered 37,796 disclosures that met selected quality assurance criteria , including: unique combin ation

of fracture date and API well n umber; fracture date between January 1, 2011, and February 28, 2013; and criteria for

water volumes. Disclosures that did not meet these criteria w ere excluded from an alysis (734)

.

153Analysis of Data from FracFocus 1.0 March 2015



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154Analysis of Data from FracFocus 1.0 March 2015



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