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.pdf
HYDRAULIC FRACKING - PROCESS
POROSITY & PERMEABILITYKey Parameters for Oil & Gas Exploration
PermeabilityPorosity 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
ShalePorosity – Very HighPermeability – Very Low
Sandstone Porosity – HighPermeability - High
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.
According to EPA 2 to 5 million gallons of water are required to fracture a single well.
Typically injection90% water10% sand (~300,000 lbs of proppant)0.05% chemical additives
Among water used63% - 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)
HYDRAULIC FRACTURING RELATED FACTS
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:
Additive (Chemical Category)
Purpose
Acid
Helps dissolve minerals and initiate cracks in the rock
Acid/Corrosion Inhibitor Protects casing from corrosion
Base Carrier Fluid (Water)
Create fracture geometry and suspend prop pant
Breaker
Allows a delayed breakdown of gels when required
Clay and Shale stabilization/Control
Temporary or permanent clay stabilizer to lock down clays in the shale structure
Cross linker Maintain viscosity as temperature increases
Friction Reducer
http://fracfocus.org/chemical-use
Reduces Friction effects over Base water in pipe
Additive (Chemical Category) Purpose
Gel Thickens the water in order to suspend the proppant
Iron Control Iron chelating agent that helps prevent precipitation of metal oxides
Non-Emulsifier Used to break or separate oil/water mixtures (emulsions)
pH Adjusting Agent/Buffer Maintains the effectiveness of other additives such as cross linkers
Propping Agent Keeps Fractures open allowing for hydrocarbon production
Scale Inhibitor Prevent scale in pipe and formation
Surfactant Reduce surface tension of the treatment fluid in the formation and helps improve fluid recovery from the well after the frac is completed
Biocidehttp://fracfocus.org/chemical-use
Eliminates bacteria in the water that can cause corrosive by products
Chemical Number of Products that Contain Specified Chemical (on the left)
Methanol 342
Isopropanol 274
Crystalline silica 207
Ethylene glycol monobutyl ether 126
Ethylene glycol 109
Hydro treated light petroleum distillates
89
Sodium hydroxide 80
CHEMICALS REPEATING IN MANY COMPOUNDS
ENVIRONMENTAL IMPACTS
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.
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.
IMPACT ON GROUND WATER
ENVIRONMENTAL PERMITS AND PROCESS
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 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.
NRDC’s Efforts
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.
• Ground water 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.
Pennsylvania Regulations (Contd.)
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.
• 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.
Louisiana Regulations (Contd..)