Human Health Risk Assessment of Hydraulic Fracturing

Andrew Pawlisz, D.A.B.T.

December 2013 Dallas, TX

Introduction Presentation Outline:

1. Disclosures 2. Shale Gas & Oil Exploration 3. Regulatory and Public Issues 4. Risk Literature Review 5. Conceptual Exposure Models 6. Chemical Identity 7. Toxicity 8. Reported Risks 9. Information Gaps 10. Conclusions

Shale Gas & Oil Exploration • Increased application of hydraulic fracturing

(frac) in US and worldwide • First experiment in 1947 • 40 North American shale plays in

exploration and development • Over 1 million frac operations completed in US • Further expansion projected Source: King (2011); Sieminski (2013)

Shale Gas&Oil Exploration

Aquifer

Shale Plays

Drilling Contractor (2013)

Over 6,000 producing wells

Fort Worth, TX

Odessa, TX

Denton, TX

Dallas, TX

Regulatory and Public Issues • Relatively clean alternate fossil energy source • More energy per CO2 than coal • Reduction in reliance on imports • US#1 energy producer (WSJ 2013) • Unconventional gas sources from nil to 30% in 2011 • Concerns with environmental impacts, groundwater

and flowback/produced water • Regulatory, public, and political pressures (e.g., bans,

law-suits, media coverage, demonstrations) • Attribution challenge: conventional vs. unconventional

Source: Vidic (2013)

Regulatory and Public Issues

Adgate (2013)

Risk Information: Media

Risk Information: Science “Trust, but verify.” Scientific Method: 1. Observe 2. Hypothesize 3. Test 4. Conclude 5. Replicate Results to Verify

Risk Literature Review • Search on “Fracking” and “Hydraulic Fracturing” • Abundant Media Coverage

• Several Review Publications by Various Groups • Peer-Reviewed Human Health Risk Evaluations

Conceptual Exposure Model - Worker

Conceptual Exposure Model - Resident

100 to 500 m radius for air exposures

Chemical Identity • As many as 750 chemicals used (US Energy and Commerce 2012) • USEPA identified 1,000 chemicals (USEPA 2012; GW report due 2014) • 347 unique CAS entries (8 states require listing on fracfocus.org) • Trade Secret constituents exempt (with exceptions) • Many not under SDWA and 27 may be hazardous (USEPA 2012) • Frac fluid composition (Fontaine 2008):

- Water (up to 99%; 2 to 7 MG per well; 10% recovered as flowback and up to 90% recycled) - Proppants (up to 1.9%) - Friction reducers (0.025%) - Disinfectants (up to 0.05%) - Surfactants (up to 0.002%) - Thickeners (not common) - Scale inhibitors - Corrosion inhibitors (up to 0.5%) - Acids

Chemical Identity

• Inbound Media: o Typically a fresh water solution fortified with chemicals and

propping media to aid in fracking • Outbound Media: o E.g., NaCl, hydrocarbons (e.g., benzene), elements (e.g., As,

Ba, Sr, Ra, Rn, U, Th, Fe, K) o Formation-specific o Not unique to fracking except for media additives

• Fluid Additives (CEC 2011): o Methanol o Glycols o Diesel o Naphthalene o BTEX o Aldehydes (e.g., glutaraldehyde)

• Formation Elements Detected in Exposure Media: o Benzene o Radium o Boron o Strontium o No Exposure Data on Additives

Chemical Identity

Toxicity Potential CONSTITUENT CAS RfC

OSHA-PEL NIOSH-REL

TWA STEL TWA STEL

Glutaraldehyde 111-30-8 0.00008 - - 0.8 C -

Diethanolamine 11-42-2 - 2 - 15 -

NaphthaleneC 91-20-3 0.003 50 - 50 75

AcetaldehydeC 75-07-0 0.009 360 - - -

FormaldehydeC 50-00-0 0.010 0.922 2.46 0.020 0.123

BenzeneC 71-43-2 0.03 3.19 16.0 0.319 3.19

p-Xylene 1330-20-7 0.1 435 655 435 655

Ethylene Glycol 107-21-1 0.4 - - - -

EthylbenzeneC 100-41-4 1 435 - 435 545

2-Butoxyethanol 111-76-2 1.6 240 - 24 -

Methanol 67-56-1 4 260 - 260 325

Toluene 108-88-3 5 754 1,885 375 560

units: mg/m3

Synopsis of Reported Risks • Air (on-Site): o Air quality study at drilling pads (OSHA/NIOSH 2012)

o Levels of silica dust above work place standards o Increased potential for lung silicosis and lung cancer o Advisory issued and a new rule proposed (OSHA 2013) o Use of personal protective equipment will mitigate this risk o Diesel exhaust impacts (Rodriquez 2013)

Synopsis of Reported Risks • Air (off-Site): o Parachute, CO complaint linked to gas condensate overflow o CO risk assessment using local air quality data (McKenzie 2012)

o CO study estimated elevated risks after 70 yrs exposure (SRI 2008) o CDPHE (2010) study in CO did not indicate unacceptable risks o Air study near CO drill rigs indicated NMHCs (Colborn 2013) o WY study indicated acceptable levels of volatiles (Sierra 2011)

Nygaard (2013)

Synopsis of Reported Risks • Air (off-Site): o Air quality investigations in Dish (aka Clark), TX (Hamilton 2012)

o Health complaints near gas processing facility (OGAP 2011) o No clear link between complaints, health study, and air results o Emissions reduced via engineering controls

o Texas (TCEQ 2010) and Arkansas (ADEQ 2011) air quality monitoring data showing elevated levels of VOCs near active rigs and compressor stations, but not frac operations

o DRI (2010) study shows a steep air levels gradient (100 m radius) o Carmichaels, PA complaint by a resident near a compressor station o PADEP (2011) air monitoring revealed low potential for acute risks o USURF (2011) low levels of benzene in air o Brown (2013) PA Health Project

Air Monitoring Data

Moore (2013)

Synopsis of Reported Risks • Frac Fluid (on-Site): o Accidental releases (Wiseman 2013) o Alleged exposure of worker/nurse in Durango, CO (Tsou 2012) o Blow-outs (TCCG 2011) o BMPs and controls designed to prevent exposure (Nygaard 2013)

• Frac Fluid (off-Site): o Releases to pastures in PA (PP 2010) and LA (PP 2009) o Treatment system residual emissions in PA (Olmstead 2012) o Spills (Bamberger 2012) o Transportation accidents (King 2012) o Blow-outs (DC 2013)

Synopsis of Reported Risks • Groundwater: o Barnett Shale study on private wells show As, Se, and Sr above

drinking water criteria near gas wells (Fontenot 2013) o Frac fluids not commonly detected (Howarth 2011) o Many may pre-date frac operations, non-baseline data o Most focus on methane (Osborn 2011) o Published events allegedly tied to fracking:

o Dimock, PA (StateImpact 2013) o Pavillon, WY (PADEP 2009)

o Rare occurrences caused by non-standard conditions o Boyer (2012) PA GW study on 233 DW wells indicates no impacts o Warner (2012) PA GW study suggest natural links to formations o GW impacts likely prevented by adhering to design specifications

and BMPs (e.g., green completions by 2015)

Synopsis of Reported Risks

Fontenot (2013)

• Surface Water: o Illegal dumping (Hunt 2013) o Pennsylvania and North Dakota (Kusnetz 2012) o Blacklick Creek, PA o Stevens Creek, PA (PR 2013) o Monongahela River, PA o Mahoning River, OH o Brush Run, PA

Synopsis of Reported Risks

Information Gaps • Baseline GW sampling data • Results for specific fluid additives • Proprietary constituents • Small- and large-scale epidemiological studies • Long-term exposure monitoring trends • Hypothetical, but realistic human health risk assessments • Relative risk statements • HF-specific parameters

Monitoring Program

• Sentinel Constituents: - Representative - Not easily biodegradable - Easy to test for - Have solid standards - Detection limits to meet toxicity thresholds - Results can be used for many purposes (i.e., 29

potential carcinogenic risk drivers; USEPA 2012)

Monitoring Program • Proposed Analytical Methods (USEPA 2012):

Alcohols: SW-846 Methods 5030 and 8260C Aldehydes: SW-846 Method 8315 Alkylphenols: No standard method Alkylphenol ethoxylates: No standard method Amides: SW-846 Methods 8032A and 8316 Amines (alcohols): No standard method Hydrocarbons: SW- 846 Methods 5030 and 8260C Carbohydrates: No standard method Ethoxylated alcohols: ASTM D7485-09 Glycols: Region 3 Draft SOP Halogens: SW-846 Method 9056A Inorganics: SW-846 Methods 3015A and 6020A Radionuclides: SW-846 Method 9310

Monitoring Program • Inbound Fluid Sentinels: o Formulation/region/operator-specific o Aldehydes, amides, alcohols, glycols

• Outbound Fluid Sentinels: o Formation-specific o NaCl, benzene, Br, Ba, Sr, Ra, Rn, U, Th

• Method Limitations • Matrix Interference • Applicability to a given media • More guidance from USEPA coming in 2014

Summary and Conclusions • Growth in the shale plays to continue • Regulations and monitoring catching up, but pressure will linger • Engineered shale gas wells designed to protect GW • Mechanical failures occur in modern life, albeit at a low rate • Reported impacts are not exclusive to HF • Unequal risk perception (Walkerton E. coli vs. HF risks) • Air impacts limited to 100 – 500 m radius • Well completion brief – key in prospective risk assessments • Individual complaints vs. health study results • Green chemistry and green well completions • Increased monitoring to provide a baseline • Continue scientific progress (and fill information void)

Thank You

Krum, Texas – July 2013