Natural Gas Drilling and Marcellus Shale
Natural gas drilling in Pennsylvania state forest. Photo by Tom Pelton/CBF Staff
Safeguarding Our Waters from Drilling Contamination
As energy companies across the nation position themselves to tap into our country's natural gas reserves, many residents and environmentalists are concerned about the potential problems associated with extracting this valuable resource. No one disputes the need for local clean, efficient energy resources. But there are concerns over the land and water impacts drilling may cause.
About Marcellus Shale and the Hydraulic Fracturing Process
The Marcellus Shale rock formation—lying beneath parts of New York, Pennsylvania, Ohio, Maryland, Virginia, and West Virginia—holds huge supplies of cleaner-burning natural gas. In a process called hydraulic fracturing, drilling companies inject millions of gallons of water—mixed with a variety of chemicals and sand—into the shale at high pressure to crack the rock and release the natural gas.
Different wells need different amounts of fluids, ranging from 1 to 9 million gallons. Once the gas has been freed, some of that water, generally between 20-50 percent, comes back to the surface. That flowback is contaminated with salt, minerals, chemicals, and, in some locations, naturally-occurring radioactive isotopes. The remainder remains deep underground where it may eventually affect groundwater aquifers and local streams. Another method of disposal is to pump the fluids into a large, lined impoundment ponds or storage tanks, to be vacuumed up later and shipped by fleets of tanker trucks to a wastewater plant. Increasingly, some companies "recycle" portions of the fluids for use in other wells.
The Concerns About Natural Gas Drilling
The environmental, human health, and community challenges presented by natural gas drilling cannot be underestimated. Some of these include:
- Contamination of groundwater, drinking water, and local streams with toxic chemicals, high levels of salt, and even naturally-occurring radioactive materials.
- Vital habitat, forest, and pristine public lands, converted to well pads, pipelines, roads, impoundments and other infrastructure.
- Accelerated stormwater runoff—and its resulting increase in nutrient and sediment levels in nearby streams—as extensive areas are cleared, roads are degraded, and soils are compacted.
- Increased air pollution due to the hundreds to thousands of tanker truck trips necessary to bring water and equipment to a single well into production, as well as thousands of compressor stations, potentially leaking methane and toxic gases into the air.
- Costly stress on roads, bridges, and other infrastructure from fleets of tanker trucks.
- If wells are abandoned, inadequate bonding may not cover the cost of properly plugging a well, leaving the state to cover the remaining costs.
- Outdated or inadequate requirements for how far wells must be placed from drinking water supplies, streams, wetlands and floodplains.
These and other challenges underscore the need for comprehensive analysis of the environmental and quality of life impacts of long term drilling across the Chesapeake Bay watershed.
CBF does not oppose natural gas development if done safely, nor have we called for a permanent ban on gas development in the region. Instead, we have embraced the precautionary principle. Our over-arching goal is to ensure that future energy development in the Chesapeake Bay region takes place in as safe and environmentally responsible a manner as possible. We are calling for a federal study of cumulative impacts of all unconventional natural gas extraction in the Marcellus shale basin and pending exploration activities in the Taylorsville basin.