July 31, 2010
Protecting watersheds in the Marcellus Shale region and forcing driller disclosure of fracking chemicals are the foremost demands of those concerned about potential environmental harm from natural gas activity.
The focused attention leaves out potentially greater threats, said Conrad "Dan" Volz, Ph.D., director and principal investigator of University of Pittsburgh's Center for Healthy Environments and Communities. The region's air could face a so far undetected threat, he said.
While a spill at a natural gas drilling site that contaminates water is catastrophic, air pollution can be a more insidious problem - one he said he feels is being overlooked.
While environmental groups and citizens scour lists of chemicals added to hydraulic fracturing fluid used to break up the shale formation, the greater threat may come from toxins that come to the surface as flowback, said Mr. Volz. He said state air-monitoring stations tend to be located in urban areas, away from rural areas where much of the drilling would be taking place.
He said the flowback is a slurry that can contain naturally-occurring benzene, strontium and arsenic. The flowback is often stored in uncovered fracking ponds where volatile organic compounds evaporate into the air. Condenser stations, wells and pipelines also discharge VOCs.
VOCs, both manmade and naturally occurring, are emitted into the air by certain liquids and solids. Some can adversely affect health in cases of chronic exposure, according to the Environmental Protection Agency.
VOCs emitted by a single well pad may not be that significant, and Dr. Volz said there's debate over the risk to air quality and health. But as drilling intensifies, however, air quality will become an issue, he said.
Dr. Volz delivered his comments at a rollout of his group's Marcellus Shale website, www.fractracker.org, to a group of stakeholders that included economic development officials, environmental groups and academics in Danville on Thursday.
He hopes Fractracker.org will help inform policymakers on issues such as where to place permanent air-monitoring stations.
Compounding air quality unknowns is the lack of state Department of Environmental Protection air-monitoring stations in many parts of the Marcellus Shale region. The stations tend to be in urban areas with historically high industrial activity. Stations are in Swiftwater, Peckville, Scranton, Wilkes-Barre and Nanticoke. None are in Wayne, Wyoming, Susquehanna or Bradford counties, where drilling activity is more common.
The DEP has a mobile air-quality lab collecting data around natural gas activity. The data has not been released, said DEP spokesman Mark Carmon. But Mr Carmon said it can provide a snapshot of the impact of natural gas activity on air quality.
Chris Tucker, spokesman for Energy In Depth, an oil and gas producers' association, said open fracking pits are increasingly being replaced by closed loop systems such as one being used by Anadarko Petroleum Corp., reducing the release of VOCs.
He also said that unlike natural gas in Southwestern Pennsylvania, natural gas coming from the Northeast is so- called "dry gas," nearly pure methane, with fewer condensates and VOCs.
University of Scranton chemistry professor Michael C. Cann said thousands of different chemicals come out of the earth in fracking fluid, but without research or testing, it's hard to assess the impact of the process.
"Certainly there are dangerous, naturally-occurring volatile organic compounds, but without research and testing, there's no way to know the risk," Dr. Cann said.