Marcellus Gas Drilling and Water Resources
Post on 02-Jan-2016
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Marcellus Gas Drilling and Water Resources
PA’s abundant water resources - a blessing and a concern
Bigger rigs More wastewaterMore waterMore disturbance
Marcellus drilling involves ….
Hydrofracturing
83,000 miles of streams Thousands of ponds/lakes 80 trillion gallons of groundwater
Water Resources Concerns
Photo courtesy – Paul Hart, Hart Resource Technologies, Inc
Regulations and enforcementImpact of water withdrawals
Protection of drinking water
Fracing chemicals
Adequate wastewater treatment
Protection of Drinking Water Supplies
• One million homes, 3.5 million residents
• Use groundwater
• Are drilling regulations protective enough?
• Are homeowners aware of water testing documentation needed and leasing stipulations?
Wells drilled 1966-1994
Water Well Studies
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Northeast PA - 200 wells
McKean County - 200 wells
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Contaminant
Some recent western U.S. studies indicate higher contamination rates
Symptoms of Problems Erosion/sediment in surface water
Changes in water appearance Sediment during construction or drilling Effervescence, spurting faucet Foaming
Changes in drinking water taste
Metallic (iron, manganese) Salty (chloride)
Changes in water odor
Changes in well or spring yield
Freshwater Use During Shale Drilling
Access + Allocation
Typically 3 to 4 million gallons of water per gas well
Freshwater Use for Drilling Withdrawal must be permitted
River basin commissions DEP permit Clean Streams Law
Water withdrawals Purchase water from communities Large rivers and impoundments Small streams and groundwater Incentives – wastewater use and
storage of water during spring
Biggest concerns Withdrawals in western PA with no
river basin oversight Illegal withdrawals - enforcement
Hydrofracturing
• Several million gallons of water mixed with sand (proppant) and various additives
• 30-40% return of frac fluids = >100,000 gallons
Hydrofracturing Mixtures
Source: Arthur et al. 2008. Hydraulic Fracturing Considerations for Natural Gas Wells of the Marcellus Shale. The Ground Water Protection Council , 2008 Annual Forum, Cincinnati, OH.
Salt (sodium, chloride, total dissolved solids)
Metals (iron, manganese, barium, arsenic)
Chemical oxygen demand
Surfactants/detergents
Total suspended solids
Oil and grease
Methane gas (migration)
Additives
Wastewater Pollutants(drilling, brine, flow-back, production)
Challenges Limited existing capacity Volume of wastes Highly polluted, variable waste
Treatment methods Dedicated facilities – salt discharge Road spreading – limited circumstances Deep injection wells – limited number + capacity POTW’s – just diluting waste, stop gap measure Reuse / recycle – dilute waste for reuse
New regulations will prohibit high TDS discharges in 2011 New treatment plants to remove salts will be needed
Wastewater Treatment
Regulations and Enforcement Sufficient setback distances to water
Sufficient bonds during permitting
Well construction to prevent methane migration
Inspections on freshwater protection string
Zone of presumed responsibility (1,000’ enough?)
Water testing burden on homeowners
Waste fluid collection – pits with liners – leaks?
Proper chemical storage on sites – preventing spills
Tracking of waste fluids – preventing illegal dumping
Staff to investigate complaints (10 days / 45 days)
Educational ResourcesGas Drilling and Water Resources
Publications Web sites / webinars
Portable Classroom DVD • Gas drilling and your private water supply
• Water stipulations for gas leases
• Treatment options for gas waste fluids
• Gas well drilling and water resources
Presentations
Questions?
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