Prodded by the federal Environmental Protection Agency, Pennsylvania says it's expanding the scope of water tests for radium and other pollutants from the state's booming natural gas drilling industry.

The Department of Environmental Protection's acting secretary, Michael Krancer, tells EPA that he's requiring additional tests by some drinking-water suppliers and wastewater treatment facilities.

Radium, which exists naturally underground, is sometimes found in drilling wastewater that gushes from drilled wells. Krancer also says he wants to add testing stations on affected rivers.

Krancer says some testing was happening before EPA made its request last month. Officials say earlier tests from seven waterways showed no harmful levels of radium.

Unlike most big gas states, Pennsylvania allows partially treated drilling wastewater to be discharged into rivers from which communities draw drinking water.

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