Though recent radioactivity tests done in Pennsylvania rivers have come back "at or below" safe levels, U.S. EPA is asking the state to perform additional tests within 30 days on water at treatment plants.

In a letter sent to Pennsylvania yesterday, EPA is also requiring that all state-issued permits be reviewed to see whether treatment plant operators handling waste from natural gas drilling are within the law. The state must send data to EPA so the federal agency can decide whether permits are strict enough.

"EPA is prepared to exercise its enforcement authorities as appropriate where our investigations reveal violations of federal law," the agency said in its letter.

Recent reports have shown that wastewater from the natural gas industry contains high levels of radioactivity and is being sent to treatment plants not designed for radioactive materials. Processed water is then discharged into waterways.

Environmental groups say the state failed to capture this radioactivity because the state's sampling sites were upstream from the treatment plants.

Katy Gresh, a spokeswoman for the Pennsylvania Department of Environmental Protection, said the agency was still examining future sampling and testing. In the meantime, Conrad Volz, director of the Center for Healthy Environments and Communities at the University of Pittsburgh, said he plans to release results tomorrow on testing conducted on wastewater discharged into Blacklick Creek from a treatment plant.

Volz did not test for radioactivity but said he found other contaminants, some at more than 10,000 times the safe standard for drinking water.

"As long as we are going to allow oil and gas wastewater to enter these streams," Volz said, "there needs to be monitoring weekly at least for a whole host of contaminants, including radium, barium, strontium" (Ian Urbina, New York Times, March 7). -- AP