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Proceedings of the Technical Workshops for the Hydraulic Fracturing Study: Chemical & Analytical Methods

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Proceedings of the Technical Workshops for the Hydraulic Fracturing Study: Chemical & Analytical Methods EPA 600/R-11/066 | May 2011 | www.epa.gov Proceedings of the Technical Workshops for the Hydraulic Fracturing Study: Chemical & Analytical Methods U.S. Environmental Protection Agency EPA 600/R‐11/066 May 2011 Proceedings of the Technical Workshops for the Hydraulic Fracturing Study: Chemical & Analytical Methods Office of Research and Development US Environmental Protection Agency Washington, DC Table of Contents List of Figures .......................................................................................................................... ii List of Tables........................................................................................................................... iv Introduction ............................................................................................................................ 1 Workshop Participants ............................................................................................................ 3 Agenda .................................................................................................................................... 5 Summary and Abstracts from Theme 1: Fracture Fluid Chemistry ............................................ 8 Summary of Presentations for Theme 1: Fracture Fluid Chemistry ............................................... 9 Summary of Discussions Following Theme 1: Fracture Fluid Chemistry Presentations ............... 11 Abstracts for Theme 1: Fracture Fluid Chemistry ......................................................................... 14 Hydraulic Fracturing Fluid Considerations in Marcellus Shale Completions ............................................................ 15 High Rate Hydraulic Fracturing Additives in Non‐Marcellus Unconventional Shales .............................................. 17 Unconventional Fracturing Fluids ............................................................................................................................ 22 Produced Formation Water Sample Results from Shale Plays ................................................................................. 34 Trace Metal Chemistry and Mobility in the Marcellus Shale ................................................................................... 38 Fracture Fluid Additive and Formation Degradations .............................................................................................. 40 Evaluating Interactions of Fracturing Fluids and Degradation Products with Radionuclides Contained in Organic‐ rich Solid‐Phase Host Materials ............................................................................................................................... 43 Summary and Abstracts from Theme 2: Chemical Fingerprinting ........................................... 45 Summary of Presentations for Theme 2: Chemical Fingerprinting .............................................. 46 Summary of Discussions Following Theme 2: Chemical Fingerprinting Presentations ................ 48 Abstracts for Theme 2: Fracture Design and Stimulation ............................................................. 52 Chemical and Isotopic Tracers of Natural Gas and Formation Waters in Fractured Shales..................................... 53 Distinguishing the Source of Natural Gas Accumulations with a Combined Gas and Co‐produced Formation Water Geochemical Approach ............................................................................................................................................ 60 The Origin of Some Natural Gases in Permian through Devonian Age Systems in the Appalachian Basin & the Relationship to Incidents of Stray Gas Migration .................................................................................................... 64 Tracking Fracture Fluid Movement with Chemical and Gamma‐emitting Tracers with Verification by Microseismic Recording ................................................................................................................................................................. 70 Designing a Water Quality Program for Shale Exploration ...................................................................................... 76 Elucidating Water Contamination by Fracturing Fluids and Formation Waters from Gas Wells: Integrating Isotopic and Geochemical Tracers ......................................................................................................................................... 81 Summary and Abstracts from Theme 3: Field and Analytical Challenges ............................... 84 Summary of Presentations from Theme 3: Field and Analytical Challenges ................................ 85 Summary of Discussions Following Theme 3: Field and Analytical Challenges Presentations ..... 86 Abstracts for Theme 3: Field and Analytical Challenges ............................................................... 89 Quality Assurance, Quality Control and Method Performance Considerations for Chemical Testing of Environmental Samples Impacted by Hydraulic Fracturing Fluids ........................................................................... 90 Determination of Total Organic Carbons in Difficult Sample Matrices Utilizing the Supercritical Water‐Oxidation TOC Procedure ......................................................................................................................................................... 98 Practical Quantitation, Method Detection Limits, Interferences and Dilution Challenges .................................... 103 Challenges for Precise Radium Analysis in Brine .................................................................................................... 109 Revisiting the Major Discussion Points of the Technical Presentation Sessions .................... 111 Summary of Discussions Following Workshop and Theme Lead Summaries ............................ 112 Glossary of Terms ................................................................................................................ 114 i List of Figures Figure 1. Effect of capillarity on water saturation (after Holditch, 1979) .................................... 33 Figure 2. Effect of water imbibtion on relative permeability changes (after Keelan, 1975) ........ 33 Figure 3. Cross‐section of Illinois Basin from Schlegel et al. (in press) ......................................... 53 Figure 4. Methane to ethane + propane ratios versus carbon isotopes of methane for various gas ................................................................................................................................................. 54 Figure 5. Carbon isotopes of carbon dioxide versus methane for various gas sources ............... 55 Figure 6. Chloride vs. bromide concentrations (log‐scale) of formation waters associated with various gas sources ....................................................................................................................... 56 Figure 7. Stable isotopes of formation waters associated with natural gas accumulations ........ 56 Figure 8. Carbon isotopes of dissolved inorganic carbon (DIC) versus alkalinity concentrations of formation waters associated with natural gas accumulations ..................................................... 57 Figure 9. Isotope geochemistry for Marcellus Shale gas have expanded our view to reveal more thermally mature thermogenic methane than fit within the standard isotope crossplot, and that also reveal isotope reversals (C1, C2) throughout the stratigraphic section. Similarly, stable carbon and hydrogen isotope compositions reveal a broader range for early thermogenic methane. ....................................................................................................................................... 66 Figure 10 provides a small dataset of a much broader database documenting isotope compositions of thermogenic gases in areas across the Central and Northern Appalachian basin. In addition, recent geochemistry for Marcellus shale gas (unpublished data, Baldassare, 2011) and deeper natural gas resources in areas of the Appalachian basin reveal a complicated thermogenic history that cannot be explained by current hydrocarbon generation models (Burruss, Laughrey, 2010). ............................................................................................................ 67 Figure 11 provides a small dataset of a much broader database documenting isotope compositions of thermogenic gases in areas across the Central and Northern Appalachian basin. In addition, recent geochemistry for Marcellus shale gas (unpublished data, Baldassare, 2011) and deeper natural gas resources in areas of the Appalachian basin reveal a complicated thermogenic history that cannot be explained by current hydrocarbon generation models (Burruss, Laughrey, 2010). ............................................................................................................ 67 Figure 12. A sequential or zipper fraced well pair in Tier 2 of the Barnett was drilled in a NNW direction in an area with possible faulting in the Ellenberger (immediately below the Barnett) with general primary frac direction of NE/SW. Well T1H has 8 stages; well T2h has 10 stages. Each stage was approximately 200,000 lb 100 mesh sand (1000 lb/ft); 7400 bbls water ( 40 bbls/ft of lateral); 6 perf clusters per frac stage; 1 bpm/perf; design frac rate was 50 bpm. ...... 72 Figure 13 shows an unexplained pumping pressure break at about 60 minutes. ....................... 72 Figure 14. 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