Environmental Impacts, Permits, and Permitting Process - UNO-EF

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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.pdf
HYDRAULIC FRACKING - PROCESS
POROSITY & PERMEABILITY
Key Parameters for Oil & Gas Exploration
Porosity
Permeability
Open Pores Space
= ------------------------ x 100
Total Rock Volume
The permeability of a rock is a
measure of the resistance to the
flow of a fluid through a rock.
Example: Sandstone 8% porosity, mean
8% open space for oil, gas, water, air.
Units of Permeability = millidarcy
SANDSTONE Vs. SHALE PERMEABILITY
Sandstone
Porosity – High
Permeability - High
Shale
Porosity – Very High
Permeability – Very Low
TRADITIONAL AND NEW RESOURCES
Advances 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:
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
Reduces Friction effects over Base
water in pipe
http://fracfocus.org/chemical-use
Additive (Chemical Category)
Purpose
Gel
Thickens the water in order to suspend the
proppant
Iron chelating agent that helps prevent
precipitation of metal oxides
Used to break or separate oil/water
mixtures (emulsions)
Maintains the effectiveness of other
additives such as cross linkers
Keeps Fractures open allowing for
hydrocarbon production
Prevent scale in pipe and formation
Iron Control
Non-Emulsifier
pH Adjusting Agent/Buffer
Propping Agent
Scale Inhibitor
Surfactant
Biocide
http://fracfocus.org/chemical-use
Reduce surface tension of the treatment
fluid in the formation and helps improve
fluid recovery from the well after the frac
is completed
Eliminates bacteria in the water that can
cause corrosive by products
CHEMICALS REPEATING IN MANY COMPOUNDS
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
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.
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
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.)
• 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.
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.
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