Hydraulic fracturing & its environmental & health implications

Rosemary FergusonLetterkenny Institute of Technology

Science DepartmentAnalytical & Forensic Science

Energy- ‘ability to do work’

Renewable • Solar• Hydropower• Biomass- harvests• Geothermal- heat from

inside the earth

Non-renewable• Nuclear power

fossil fuels• Oil/Petroleum• Natural gas• Coal

•Reliance on foreign producers•90% of natural gas consumed in the US in 2010 was produced domestically

Source formationConversion of organic material to hydrocarbons by kerogen maturity Geology of natural gas resources

What is Shale Gas?

• Shale- fine grained rock produced from clays under pressure

• Shale gas- formed due to decay of organic material over a long time and under huge pressure

• Unconventional gas- so called because it is trapped in small pores in the rock

• Seismology-creation of a vibration on the surface & recording the reflected vibration → geological profile of ground formation beneath

Fracking•Directional drilling - access the thin layer of shale with long laterals for exposure to a large area•High frac fluid volumes - stimulate gas release from fractures•Slickwater -chemicals &water to reduce the amount of friction & control the amount of power needed to pump the large volumes of frac fluids at high pressures, quickly, over long distances through small diameter cement casing•Multi well pads - access as much of the gas inventory as possible

Concerns

Methane contamination

of drinking water wells

Health implications

Migration of induced

fractures & fracturing fluids

Lack of legislation- Halliburton

loopholeLack of health

professionals on advisory

committees

Fracture & fluid migration

• Ingraffea conducted physical & computer simulation testing in the Lawrence Livermore National Laboratory for the Unconventional Gas Program in Schlumberger Terra Tek 1984-87. The ‘ideal’ rock did not compare to the computer simulation →unpredictable problem of non-linear chaos; where any slight change in any of the conditions (pressures/tension, flow characteristics of the joint, permeability) results in a big change in the answer

• In 2008 Veatch reported what is still unknown; depth of penetration, vertical extents, symmetries, planar or multi-stranded, direction & their conductivities

0%10%20%30%40%50%60%70%80%

Health effects of chemicals in fracturing fluids on systems

Health effects of chemicals in fracturing fluids

Colburn et al (2010)632 chemicals-353 CAS numbers

Endocrine disrupting chemicals(EDC)

Law outlined 3 chemicals used as known EDC’s• Arsenic- interacts with 7 of the nuclear receptor super-

family & is linked to Type II diabetes• Thiourea- anti-thyroid medications → reduce production

of the thyroid hormone• Cadmium- androgen & oestrogen receptor agonist,

prostate cancer in rats & implicated in breast cancerSynthetic organic chemicals → potential EDC’s → non-

monotonic dose responsive curves→ adipose tissue→ fat deposits(¹/₂ life’s) → circulation system

Methane contamination of drinking water wells

Methane found in 51 of 60 wells (Osborn et al 2011)• concentrations 17 times higher (19.2 mg CH4 L-1) in wells from

active (<1km) drilling sites than wells from non-active (>1km) sites (1.1 mg CH4 L-1)

• δ13 C-CH4 <-50% → thermogenic methane, >-64% →microbial methane (Schoell 1980)

• δ13 C-CH4 (-37 7%) in shallow groundwater <1km → thermogenic methane, in contrast with groundwater >1km lower methane conc. of -54%11%.

• Hydrochemistry of active wells showed no contamination of chemicals derived from produced waters

EPA case study

Monitored drinking in homes in Wyoming & found organics used in fracturing fluids in their aquifers

→Still under dispute

Conclusions

• Unavoidable environmental impacts→ land usage, transport

• Current regulatory framework does not cover hydraulic fracturing

• Co-operation between industry, state regulatory agencies, health professionals & university researchers

• Full life cycle analysis of process required- air, water & epidemiology monitoring programs

• Introduction of trackers in fracturing fluids

References• Colborn, T., Kwiatkowski, C., Schultz, K., Bachran, M., 2010. Natural Gas Operations from a Public Health

Perspective. International Journal of Human and Ecological Risk Assessment. September 4, 2010. Expected publication: September-October 2011.

• Department of Energy, 2011. Natural Gas benefits. Alternative &Advanced fuels. U.S Department of Energy. Retrieved from http://www.afdc.energy.gov/afdc/fuels/natural_gas_benefits.html on March 2nd 2012

• Energy Information Administration. 2011. Energy explained. U.S Energy Information Administration. Retrieved from http://www.eia.gov/energyexplained/index.cfm?page=about_home on March 2nd 2012

• Environmental Protection Agency. 2011. Groundwater Investigation: Pavillion. Environmental Protection Agency Region 8. Retrieved from http://www.epa.gov/region8/superfund/wy/ pavillion/ on April 1st 2012

• HESGEC. 2011. Goldstein, B.D., Law, A. 2ND Annual Health Effects of Shale Gas Extraction Conference. Pittsburgh, PA., November 18th 2011. University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA.

• Ingraffea, A. 2010. The Facts on Fracking. The Gas Drilling Awareness Coalition. Retrieved from http://www.youtube.com/watch?v=mSWmXpEkEPg on March 3rd 2012

• Osborn, S.G., Vengosh, A., Warner, N.R., Jackson, R.B., 2011. Methane contamination of drinking water accompanying gas-well drilling and hydraulic fracturing. Proceedings of the National Academy of Sciences of the United States of America. 108 (20). Retrieved from http://www.pnas.org/content/early/2011/05/02/1100682108.full.pdf+html on March 1st 2012

• Natural Gas, 2010. Overview of Natural Gas. Natural Gas Supply Association. Retrieved from http://www.naturalgas.org/overview/background.asp on March 5th 2012

• Schlumberger, 2012. Catagenesis, Diagenesis & Metagenesis. Oilfield glossary. Schlumberger Limited. Retrieved from http://www.glossary.oilfield.slb.com/DisplayImage.cfm?ID=664 on March 6th 2012

• Schoell, M. 1980. The hydrogen and carbon isotopic composition of methane from natural gases of various origins. Geochim Cosmochim Acta. 44 649-661

• Veatch, R.W. 2008. A Historical Perspective of Hydraulic Fracturing. Tulsa, Oklahoma. Retrieved from http://spemc.org/resources/presentation_011708.pdf on March 29th 2012