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EXPOSURE AND TOXICITY OF CHEMICALS RESULTING FROM NATURAL GAS EXTRACTION AND HYDRAULIC FRACTURING Debra A. Kaden, Boston, MA; Angela Harris, Little Rock, AR; John Imse, Denver, CO; Mark Travers, Chicago, IL; Rosalind Schoof, Seattle, OR www.environcorp.com INTRODUCTION What is hydraulic fracturing? • Established technology, but more widely used with advances in drilling technology (horizontal drilling) ° Over past 6-8 years, use has expanded greatly ° Opens up productivity of unconventional oil and gas resources Why the controversy? • Expansion in the public awareness regarding those resources and an intensified regulatory scrutiny of development • Unconventional resources in areas where oil and gas production has not been seen on this scale for many years ° Example: Marcellus Shale in Pennsylvania, New York, and Ohio. • Overall increased awareness of environmental issues in society • Vast array of readily available and accessible information resources WHAT ARE THE POTENTIAL EXPOSURE PATHWAYS? Inhalation • Exploratory drilling • Methane fugitive emissions • Vapor intrusion • Air toxic emission • Hydrogen sulfide • Particulates Sources • Air ° Exploration Drilling — Relatively short term from exposure perspective ° Development and Production — Longer term — Leaks and venting (methane) ° Support activities — Truck and engine exhaust — Fugitive dust • Water ° Surface water ° Groundwater ° Waste water — Volatilization from pits or impoundments Ingestion • Methane • Naturally Occurring Radioactive Material (NORM) • Salts (brine) • Various chemicals from injected fluids Sources • Well construction failure – casing and cement integrity • Direct contact with and disposal of wastewater • Possible hydraulic connections between deep and shallow aquifers • Hydraulic connections created by historical drilling in regions being developed • Wastewater release Abstract # 2112 CHEMICALS ASSOCIATED WITH HYDRAULIC FRACTURING Pollutant Emissions (tpy) Health concerns VOCs Ethane Isopentane Propane Isobutane N-Butane Ethylene N-Pentane Methane 2.2 million VOCs react in the air to form ozone and PM 2.5 . Ozone (regulated as a criteria pollutant) can cause asthma attacks, hospital and emergency department visits, school loss days, and premature mortality PM 2.5 (regulated as a criteria pollutant) can cause premature mortality for adults and infants, heart attacks and hospital admissions. Also can cause asthma attacks, acute and chronic bronchitis, hospital and emergency room visits, work loss days, restricted activity days, and respiratory symptoms. Air Toxics Acetaldeyde Benzene Toluene Ethyl benzene Xylenes 1,3-Butadiene 130,000 Including benzene, others. Can cause cancer and other serious, irreversible health effects . Regulated through the Clean Air Act. GHG Methane 16 million (300,000 MMTCO 2 e) Reacts in the air to form ozone (see above). A potent GHG. Once emitted into the atmosphere, it absorbs terrestrial infrared radiation, which contributes to increased global warming and continuing climate change. Adapted From: EPA (July 2011) Overview of proposed new regulations Study What was measured What was found TCEQ Dec 2009 Due to complaint of odor • Up to 84 VOCs over 3 days • Fixed and mobile monitors • All but 1 found non-detectable or below short-term AMVCs • p-Diethylbenzene measured above the odor-based AMCV at 1 location, but not above the health-based AMCV TCEQ Nov 2010 • 18 carbonyls • Downwind of possible sources • All non-detects or below short-term AMCVs • Formaldehyde concentrations 1-.0 – 5.4 ppbv. • Note, limit of detection of isovaldehyde above AMCV, but characteristic odor not detected. City of Fort Worth Sept/Oct 2010 (ERG report July 2011) • ~140 pollutants (> 40 HAPs) measured at 8 locations • Highest concentrations: Methane, ethane, propane, butane. • Some pollutants with greater toxicity (e.g., benzene) also found, but at much lower concentrations. • High-level activity area site had generally higher concentrations than other sites. • 2 Medium activity sites (within 350 ft of active well pads) “surprisingly low “relative to the other sites.” Zielinska et al 2010 • Non-methane volatile organic compounds (NM VOC) examined near gas well sources >90% ethane, propane, n-butane, iso-butane, iso-pentane, and n-pentane ~10% of VOC were mostly C6-C8 n-alkanes, branched- and cyclo-alkanes. ~0.1 – 0.2% benzene, toluene, and xylenes (part of BTEX) 4-week average individual VOC concentrations were low, generally <1 ppb Comparable or slightly higher than TCEQ sites (same time period) Monitoring at a nearby residential community found average speciated VOC concentrations generally <1 ppb. University of Colorado Air Toxics Study (2007-2008) Collaboration between BCPH, U Colorado, EPA Region 8 • Measured VOC, carbonyls, ozone • Source apportionment to tie back to sources From PCA results, mobile source exhaust, natural gas condensate emissions, and meteorology are significant pollution source Garfield County 2008 Monitoring CO Department of Public Health & Environment with review by ATSDR • 4 Locations within 1.5 miles of oil & gas development activities: ° 2 urban, near I 70 ° 2 rural, close to oil & gas activities • Measured 90 speciated NM VOCs (1,3-Butadiene, Benzene, Ethylbenzene, Toluene, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, others) every 6 days • Measured carbonyls (acetaldehyde, formaldehyde, crotonaldehyde, others) every 12 days • Used conservative assumptions (95% upper confidence level of mean values for chronic/ maximum values for acute; assumes 24/7, 30 years) • Cancer risk found within EPA acceptable range • Noncancer risk (acute or chronic) below health-based guidelines • Cautions: Measurements only once every 6 (or 12) days; Measurements at single station for each location; Reflect emissions from other sources too; Risk estimates use conservative, regulatory values AIR EXPOSURE DATA CONCLUSIONS Air While many of the chemicals associated with fracking are toxic (at some concentration)…. • Benzene, toluene, ethylbenzene, xylene (BTEX), other VOC ° Stationary and truck Diesel engines, flaring, venting, produced water storage, dehydration of natural gas • Methane ° Greenhouse gas (GHG) From: Zielinska et al 2010 1st 2nd 3rd Boulder Mobile Source Secondary Formation Evaporative Longmont Evaporative Secondary Formation Mobile Source Lyons Secondary Formation Evaporative Mobile Source Niwot Ridge Secondary Formation Mobile Source Evaporative South Boulder Mobile Source Evaporative Secondary Formation POTENTIAL POLLUTION SOURCE RANK BY SITE From: University of Colorado Air Toxics Study (2007-2008) Pavillion, WY • USEPA response to complaints from domestic well owners about objectionable odors and tastes from well water. • Four phases of investigation conducted March 2009 – April 2011. • Sampled residential wells, municipal wells, stock wells and monitoring wells Garfield County, CO • Garfield County Board of County Commissioners • Evaluate surface and groundwater vulnerability near gas well developments and other human activities • Four phases of investigation • Baseline groundwater studies have also been conducted in Colorado LeRoy Township, PA • Investigation conducted in 2011 to evaluate potential effects of a wellhead valve release on a well pad to nearby residential wells • Some baseline data available for comparison SUMMARY OF GROUNDWATER STUDIES Analyte (mg/L) Pavillion Garfield County Leroy Township Deep (Monitoring Wells) Shallow (Residential Wells) Baseline Studies Groundwater Baseline Residential Well 1 BTEX Benzene ND - 256 ND – 0.54 ND ND – 1.0 NR Toluene ND - 617 ND – 0.71 ND ND – 14.0 Ethylbenzene ND - 67 ND ND ND – 1.0 Xylenes ND - 750 ND ND ND – 1.5 Napthalenes ND – 6.1 ND – 0.39 NR NA NR Isopropanol 212 - 581 ND NA NA Arsenic 3.6 – 41.8 ND - .089 4.8 2 4.1 2 ND – 1.8 Uranium NA NA NR 1.5 - 47 ND - .023 1 After valve release at well pad 2 Mean value 3 Unknown methane origin: ND (not detected) NA (not analyzed) NR (not reported) Analyte (mg/L) Pavillion Garfield County Leroy Township Deep (Monitoring Wells) Shallow (Residential Wells) Baseline Studies Groundwater Baseline Residential Well 1 pH 11.2 – 12.0 6.9 – 10.0 7.8 2 7.4 2 8.42 7.3 – 8.6 Methane 16.0 – 19.0 ND - .808 ND – 36.7 3 ND - 11 0.76 .76 - 12 Anions Cl 23.1 - 466 0.6– 80.3 147.5 2 1.0 - 2300 116 1750 K 24.7 – 54.9 0.3 – 11.4 3.0 2 0.4 – 14.2 1.78 0.38 - 6.7 TPH DRO 0.63 – 4.0 ND - .10 NA NA NR NR GRO 0.39 – 3.7 ND – 0.48 NA NA • Hydrogen sulfide ° Occurs in formations with lots of pyrite, like the Marcellus ° Others: formaldehyde, diesel exhaust, 1,4-dioxane, hydrochloric acid, methanol Air exposures found to be minimal • Often not detectable • Below health-based benchmarks • Dissipate as you move away from the site • Other sources of same VOC Odor detection is not necessarily toxic REGULATORY ACTIVITIES Currently, regulation of industry largely the responsibility of states, sometimes regional commissions • Regulations vary from state-to-state ° Direct regulation (Air Pollution Control Act) ° Indirect regulation via permitting • Types of regulation ° General permitting ° Project-specific review ° Notification/registration requirements ° Common law – “reasonable use” • Several states considering moratoriums on hydraulic fracturing ° New York has temporary moratorium in place ° Vermont considering a three-year moratorium ° Ohio has proposed moratorium on horizontal stimulation until USEPA water study complete ° Michigan has proposed two-year moratorium on new permits until USEPA water study complete ° USEPA assured states it will not issue a moratorium on hydraulic fracturing • Existing or possible new state and local regulations and practices can serve to manage groundwater impacts ° Regulations for construction, maintenance and closure of both gas wells and water wells ° Baseline and ongoing groundwater well water quality monitoring ° Public disclosure of chemicals used Increased Federal Activities in Recent Years • USEPA: New rules under Clean Air Act expected by April 3, 2012 ° Includes review of four rules for the oil and natural gas industry ° New source performance standard for VOCs ° New source performance standard for sulfur dioxide ° Air toxics standard for oil and natural gas production ° Air toxics standard for natural gas transmission and storage • Includes requirement to capture 95% of VOC emissions ° Largely through capturing natural gas that currently escapes into the air, making that gas available for sale ° Will also reduce emissions of methane and air toxics Aggregation of Air Emissions • Several pending litigation actions address aggregation ° Process of determining whether emissions from multiple operations should be combined, or aggregated, into a single source for air permitting purposes • If emissions from individual operations are combined, they could constitute “major stationary source” or “major facility” for purposes of the Prevention of Significant Deterioration, New Source Review and Title V permitting programs under the Clean Air Act • Definition of “adjacent” likely to be applied differently in some of the litigation cases ° Clean Air Council v. DEP (EHB Docket No 2011-072-R), pending before Pennsylvania’s Environmental Hearing Board (USEPA Region 3) ° Citizens for the Future of Pennsylvania v. Ultra Resources, 4:11-cv- 01360-JEJ, pending in the US District Court for the Middle District of Pennsylvania (USEPA Region 3) ° Summit Petroleum Corporation v. EPA (Case No. 09-4348) pending before the federal Sixth Circuit Court of Appeals (EPA Region 5). ° Others • If different interpretations across different USEPA regions, likely USEPA will attempt to resolve conflicting Congressional bills • HR 1204: Bringing Reductions to Energy’s Airborne Toxic Health Effects Act (“BREATHE” Act) ° Eliminates NESHAP exemption to have aggregated wells viewed as “major sources” to use best available control technology ° Sponsored by Rep Jared Polis (D-Colorado 2nd District) ° Status: Bill in the first step in the legislative process. Federal Water Regulations Study on Impact of Hydraulic Fracturing on Drinking Water Resources (USEPA) • Initial study results due end of 2012; additional report based on long-term study projects in 2014. • Researchers examining impacts of: ° large volume water withdrawals from ground- and surface waters ° surface spills resulting from hydraulic fracturing fluids ° injection and fracturing process ° surface spills of flowback and produced wastewater treatment and waste disposal • Results likely to drive regulatory and policy changes—could have significant impact on the shale gas industry Development of Hydraulic Fracturing Wastewater Standards (USEPA) • National standards for wastewater discharges via Clean Water Act (CWA) effluent guidelines program • Based on best available technologies that are economically achievable • Prohibit on-site direct discharge of wastewater from shale gas extraction into US waters • Currently, disposal of wastewater regulated by the states. In some states, wastewater injected into deep underground shafts; in others, wastewater sent to sewage treatment plants • USEPA gathering data, consulting with stakeholders, soliciting public comment on proposed rule for wastewater discharges ° Proposed rule for coalbed methane in 2012 ° Proposed rule for shale gas in 2014 Permitting Guidance on Underground Injection Control for Facilities that Use Diesel Fuels in Injection Fluids (USEPA) • Safe Drinking Water Act’s (SDWA) Underground Injection Control (UIC) program has requirements for proper well siting, construction, operation to minimize risks to underground sources of drinking water • Energy Policy Act of 2005 excluded hydraulic fracturing for oil and gas production from permitting but exclusion did not include fracturing using diesel fuel • USEPA developing permitting guidance with a broad definition of diesel fuel (e.g., physical and chemical characteristics of diesel such as BTEX) Rulemaking on the Disclosure of Chemicals Used in Hydraulic Fracturing (USEPA) • EPA starting rulemaking process under Toxic Substance Control Act (TSCA) to require disclosure of information on the chemicals used in hydraulic fracturing. ° In a response to a petition filed by Earthjustice and 120 other organizations ° Will limit disclosure to substances used in hydraulic fracturing ° Will attempt to avoid duplication of “the well-by-well disclosure programs already being implemented in several states,” and will “focus on providing aggregate pictures of the chemical substances and mixtures used in hydraulic fracturing” ° Advanced notice of proposed rulemaking expected in 2012 Proposed Regulations Related to Hydraulic Fracturing on Public Lands (US Department of the Interior) • Drafting regulation for shale gas production on public lands • In addition to chemical disclosure provisions, the rules are expected to address wellbore integrity following hydraulic fracturing and the management of wastewater Other Regulatory or Industry Activities DOE Shale Gas Subcommittee: Recommendations for immediate implementation • Federal agencies ° Measures to reduce emissions of air pollutants, ozone precursors and methane as quickly as practicable (USEPA) ° Interagency planning effort to acquire data and analyze the overall greenhouse gas footprint of natural gas use • States ° Encourage shale-gas production companies and regulators to expand immediately efforts to reduce air emissions using proven technologies and practices. Federal funding at $5m/y for state regulators/NGOs/ industry will encourage planning • Industry ° Enlisting a subset of producers in different basins to design and field a system to collect air emissions data WATER EXPOSURE DATA Water Baseline studies are integral to interpreting data from groundwater studies associated with nearby hydraulic fracturing activities. The data and conclusions from one groundwater study are not generally applicable to potential impacts in another region. • Differences in underlying hydrogeology • Variability in stratography of residential wells • Potential for domestic/agricultural/municipal impacts to groundwater vary by region Precautionary Principle often cited… • Do no harm • Prove scientifically that what you are doing is not harmful ...but to date the facts do not support health risks • Still, need to move forward cautiously with air and water monitoring to make sure...
