FACT SHEET
Center Criteria For Evaluating Fracking Projects
EPA and litigants WildEarth Guardians and the San Juan Citizens Alliance have agreed to a two-week extension – until April 17, 2012 - on a consent decree to issue air pollution standards for natural gas wells developed with hydraulic fracturing. EPA, under the consent decree, faced an April 3 deadline to complete rules to cut smog-forming and toxic emissions from gas wells, compressors, oil storage tanks and other oil-and-gas sector equipment. The agency requested the additional time to fully address the issues raised in the more than 156,000 public comments we received on the proposed rules.
The rules are aimed at curbing smog-forming volatile organic compounds, emissions of benzene, which are linked to cancer, and releases of methane, which is a potent greenhouse gas. The proposal would cut smog-forming volatile organic compound (VOC) emissions by nearly one- fourth across the oil and gas industry, including a nearly 95 percent reduction in VOCs emitted from new and modified hydraulically fractured gas wells.
In addition to EPA plans to set air pollution standards for "fracked" wells, the Interior Department is crafting rules for fracking that occurs on public lands. The upcoming Interior Department proposal will require disclosure of chemical ingredients injected underground, and will also address well integrity and management of large volumes of wastewater.
Fracking involves high-pressure injections of water, chemicals and sand into rock formations in order to open up seams that enable trapped gas to flow. The Clean Air Act requires EPA to set New Source Performance Standards (NSPS) for industrial categories that cause, or significantly contribute to, air pollution that may endanger public health or welfare. Oil and gas production, processing, transmission and storage are significant sources of VOCs, which contribute to the formation of ground-level ozone (smog). The law requires EPA to review new source performance standards every eight years.
The proposal would cut smog-forming volatile organic compound (VOC) emissions by nearly one-fourth across the oil and gas industry, including a nearly 95 percent reduction in VOCs emitted from new and modified hydraulically fractured gas wells. This significant reduction would be accomplished primarily through use of a proven technology to capture natural gas that currently escapes to the air.
The proposed rules would apply to the more than 25,000 wells that are fractured and refractured each year, as well as to storage tanks and other pieces of equipment. In 2009, about 1.1 million wells were producing oil and natural gas in the United States. The wells are located in many areas of the country, including both urban and rural areas.
Some of the largest air emissions in the oil and gas industry occur as natural gas wells that have been fractured are being prepared for production. During a stage of well completion known as "flowback," fracturing fluids, water, and reservoir gas come to the surface at a high velocity and volume. This mixture includes a high volume of VOCs and methane, along with air toxics such as benzene, ethylbenzene and n-hexane. The typical flowback process lasts from three to 10 days. Compression is necessary to move natural gas along a pipeline. The proposed rule would reduce VOC emissions from two types of compressors:
Centrifugal compressors would have to be equipped with dry seal systems.
Owners/operators of reciprocating compressors would have to replace rod packing systems every 26,000 hours of operation.
Pneumatic controllers: Pneumatic controllers are automated instruments used for maintaining a condition such as liquid level, pressure, and temperature at wells, gas processing plants, compressor stations, among other locations. These controllers often are powered by high-pressure natural gas. These gas-driven pneumatic controllers may release natural gas (including VOCs and methane) with every valve movement, or continuously in some cases.
EPA is proposing VOC emission limits for pneumatic controllers.
For new or replaced pneumatic controllers at gas processing plants, the proposed limits would eliminate VOC emissions. These limits could be met through using controllers that are not gas-driven.
For controllers used at other sites, such as compressor stations, the emission limits could be met by using controllers that emit no more than six cubic feet of gas per hour. (The Hill, 4/2/2012, EPA)
For new or replaced pneumatic controllers at gas processing plants, the proposed limits would eliminate VOC emissions. These limits could be met through using controllers that are not gas-driven.
For controllers used at other sites, such as compressor stations, the emission limits could be met by using controllers that emit no more than six cubic feet of gas per hour. (The Hill, 4/2/2012, EPA)
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