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HYDRAULIC FRACKING: ENVIRONMENTAL IMPACTS, PERMITS, AND PERMITTING PROCESS. Chandra Theegala, PhD, PE Professor Biological & Agricultural Engineering LSU & LSU AgCenter. Kura Bhaskar, PhD, PE Professor & Interim Chair Associate Dean – Program Dev. Civil & Environmental Engineering
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HYDRAULIC FRACKING: ENVIRONMENTAL IMPACTS, PERMITS, AND PERMITTING PROCESS Chandra Theegala, PhD, PE Professor Biological & Agricultural Engineering LSU & LSU AgCenter Kura Bhaskar, PhD, PE Professor & Interim Chair Associate Dean – Program Dev. Civil & Environmental Engineering University of New Orleans
Acknowledgements Assistance received by Ms. Poojitha Aleti, who is a graduate student at UNO in Civil & Environmental Engineering Department is acknowledged.
Outline • Hydraulic Fracking – Process • Environmental Impacts • Environmental Permits and Process
http://www2.epa.gov/sites/production/files/documents/hf_study_plan_110211_final_508.pdfhttp://www2.epa.gov/sites/production/files/documents/hf_study_plan_110211_final_508.pdf
POROSITY & PERMEABILITYKey Parameters for Oil & Gas Exploration Permeability Porosity Open Pores Space = ------------------------ x 100 Total Rock Volume Example: Sandstone 8% porosity, mean 8% open space for oil, gas, water, air. The permeability of a rock is a measure of the resistance to the flow of a fluid through a rock. Units of Permeability = millidarcy
SANDSTONE Vs. SHALE PERMEABILITY Sandstone Porosity – High Permeability - High Shale Porosity – Very High Permeability – Very Low
TRADITIONAL AND NEW RESOURCESAdvances in Directional Drilling
HYDRAULIC FRACTURING • Increase permeability by fracturing the low-permeability oil formations to stimulate oil and gas production. • Through injection of water, permeable sand, chemicals at high pressure into a gas or oil well. • Injected proppants (sand) – keeps the fractures open when pressure is released. This assists in long term yield.
HYDRAULIC FRACTURING RELATED FACTS • According to EPA 2 to 5 million gallons of water are required to fracture a single well. • Typically injection 90% water 10% sand (~300,000 lbs of proppant) 0.05% chemical additives • Among water used 63% - From rivers, streams. 20% - Public water systems. 15% - Recycled fluid. 02% - proppants and chemicals. • Proppants are sand material that keeps bed rock fractures open to allow gas to flow out
HYDRAULIC FRACTURING RELATED FACTS • Shale runs horizontal – so directional drilling and “laterals” are key to oil & gas extraction • Laterals - 1,500-5,000 ft in Barnett Shale, Texas - up to 10,000 ft in Bakken formation, ND • Injection pressure up to 100 Mpa (15,000 psi) • Injection rate up to 9.4 cu ft/s (100 barrels/min)
CHEMICALS USED • More than 750 chemical components are used in the hydraulic fracturing products injected underground between 2005 and 2009. • Chemicals are selected based upon their advantages. • Fluid viscosity manipulation critical for proppant transport and oil/gas extraction (gels and cross-linkers) • A few chemical categories, their purpose, and select chemicals are shown in the following slides:
SIGNIFICANT ENVIRONMENTAL IMPACTS • Water – Major • Air – Due to combustion and transport activities • Solid / Hazardous Wastes - Due to chemicals transported, stored and handled
Health Effects Due to Chemicals Used in Hydraulic Fracking • Congenital heart defects. • Sinus problems, eye burning, severe headaches, persistent cough and skin rashes. • Hemolysis (destruction of red blood cells). • Damage to the spleen, liver, and bone marrow. • High blood pressure, and nerve disorders
IMPACT ON SURFACE WATER Three risks to drinking water that can occur on the surface. • Depletion of water sources. • Spills and leaks of fracking chemicals and fluids. • Mismanagement of fracking waste.
IMPACT ON GROUND WATER Four risks to drinking water that can occur below ground surface are related to: • Well construction, cementing and casing. • Out-of-zone growth. • Neighboring oil and gas wells. • Natural fracture networks.
Environmental Permits and Process • Federal • State • General State Guidelines • Pennsylvania • Louisiana
Certain Exemptions for Hydraulic Fracturing from Federal Environmental Laws*(as Per Energy Policy Act of 2005) • Clean Water Act: • Regulates quality standards for surface water and provides structure for regulating discharges of pollutants into water . • Clean Air Act: • Authorizes EPA to regulate air pollutant emissions and to protect public health and welfare. • Safe Drinking Water Act • Statues regulating quality of water whether from ground or underground sources, that are potentially designed for human consumption. *William J. Brady and James P. Crannell.
Exemptions (Contd..) • National Environmental Policy Act: • Concerns about major environmental impacts of any federal action that significantly affects environment. • Resource Conservation and Recovery Act: • Statute to regulate the generation, transportation, treatment, storage, and disposal of hazardous waste. • Emergency Planning and Community Right-to-know Act • National Legislation designed to help communities protect public health, safety, and the environment from chemical hazards.
Certain Exemptions/Clarifications • The CWA exempts stormwater discharges • Whereas, discharges resulting from construction activities are not exempt • Surface water discharges of flowback are regulated by the NPDES
Certain Exemptions/Clarifications (..Contd.) • The underground injection of fluids and proppants (other than diesel) are excluded from UIC of the SDWA • Underground injection of flowback is regulated by the UIC program. • Oil and gas exploration and production activities are exempted from EPCRA.
NRDC’s Efforts • NRDC urges the use of key management practices to minimize the risks associated with fracking activities. This includes: • Federal regulation of all hydraulic fracturing under the Safe Drinking Water Act • Regulation of toxic oil and gas waste under federal and state hazardous waste laws • Stronger standards and enforcement under the federal Clean Water Act and state laws.
IOGCC’s Efforts • IOGCC - Interstate Oil and Gas Compact Commission • IOGCC member states have all stated that there have been no cases where hydraulic fracturing has been verified to have contaminated drinking water. • Member states of IOGCC passed a resolution in January 2009 Urging congress not to remove the exemption for Hydraulic Fracturing from the provisions of the safe drinking water act. • Each state has it’s own regulations regarding Hydraulic Fracturing
Critical Disclosure Information for Permitting • Distance from well to aquifers. • Surface water drains. • Drinking water sources nearby. • Pressure, volume, type and source of the base fluid. • Source of the base fluid.
Pennsylvania Regulations • Permit: Obtain permit from PA Department of Environmental Protection by submitting plan for construction and stimulation of fracking well. • Drilling distances: Gas drilling must not occur within 200 feet of drinking water supplies. • Water contamination: Drillers are responsible for contamination if it occurs within 1000 feet from the well and within 6 months after well completion.
Pennsylvania Regulations (Contd.) • Groundwater Contamination: State legislation requires drillers to report the quantity and chemical content of produced water created by well. • Produced water disposal: Limit on TDS in produced water before disposal is 2000 mg/L. • Well closing: The state requires drilling companies to plug wells after production ceases. • Surface disturbance: Pennsylvania requires the submission of an erosion and sedimentation plan to the DEP before drilling can begin.
Louisiana regulations • Operator must obtain work permit from Louisiana department of natural resources(DNR) by submitting plan for construction and stimulation of fracking well. • Drilling permit must also be taken. • DNR requires well casings of different depths which depends on depth of well. • Flow back from hydraulic Fracturing must be stored in tanks or pits and are exempt from Louisiana hazardous waste regulations.
Louisiana Regulations (Contd..) • Temporary containment pits must be closed within 6 months of well completion to protect soil and water. • Before closing the pits, their content must be tested for pH, heavy metals, oil and grease content. • Operator is responsible for handling and transportation of waste for disposal. • Operators must disclose the composition and volume of fracking fluids they use after completing the well.