SEAB subcommittee studies environmental safety risks of shale gas

Increased transparency and best practices were emphasized in a preliminary, 90-day report from the Shale Gas Subcommittee of the Secretary of Energy Advisory Board (SEAB). The subcommittee focused on ways to reduce environmental and safety risks of US shale gas production.

The recommendations are open to public comment, and the subcommittee is scheduled to submit a final report in November.

The seven-member SEAB subcommittee issued recommendations for key areas of shale gas production although it stopped short of outlining specifics of achieving those recommendations, which largely seek to protect air and water quality.

Public concern and debate about shale gas has grown with expanding US shale gas production. Possible pollution of drinking water from methane and chemicals used in hydraulic fracturing stimulation is a key concern. Other concerns involve possible air pollution and community disruptions, such as increased truck traffic associated with shale gas exploration and production.

The subcommittee’s preliminary report called for full disclosure of chemicals used in fracing as well as for creation of a national database to consolidate all information already available to the public about shale gas.

Fracing fluid disclosure

Regional diversity of shale gas and evolving technology prohibit one best engineering practice for all locations and for all time, the subcommittee report said.

“The subcommittee shares the prevailing view that the risk of fracturing fluid leakage into drinking water sources through fractures made in deep shale reservoirs is remote,” the report said. “Nevertheless, the subcommittee believes there is no economic or technical reason to prevent public disclosure of all chemicals in fracturing fluids with an exception for genuinely proprietary information.”

Many companies already post this information on their own individual web sites, said subcommittee member Stephen Holditch, chairman of the Department of Petroleum Engineering at Texas A&M University.

The subcommittee recommends gas producers measure and publicly report the composition of fracing fluids pumped into the ground and publicly report the composition of fluids coming back out, Holditch said.

The subcommittee also called for additional field studies on possible methane leakage from gas wells to water reservoirs.

Holditch said gas producers should measure water quality and methane levels in existing water wells before gas drilling. Producers should publicly report the composition of water stocks and flow throughout the fracing and cleanup processes.

“Effective action requires both strong regulation and a shale gas industry in which all participating companies are committed to continuous improvement,” the report said.

Holditch noted that the US Department of Energy (DOE) has no mechanism or authority to implement the recommendations because DOE is not a regulator of air quality or water quality. The subcommittee talked with the US Department of the Interior and also the US Environmental Protection Agency, he said.