A state study revealing mercury hot spots in Cambria County is fueling debate over whether the state should adopt stricter mercury-emission standards or rely on weaker federal ones.

Eight years of water samples Penn State University collected for the state Department of Environmental Protection show mercury concentrations 47 percent higher in Cresson, Cambria County, downwind of Western Pennsylvania coal-fired power plants (including three in Cambria), than in Wellsboro, Tioga County, which is far removed from any power plants.

The findings support arguments that mercury emissions tend to produce hot spots around the source of emissions, a DEP release states.

The U.S. Environmental Protection Agency put mercury emission rules into effect in July and has given states until Nov. 17 to adopt stricter state mercury pollution standards. EPA's rules would reduce mercury emissions from coal-burning power plants by 70 percent by 2018. Power plants could delay installing controls for up to five years.

Given the opportunity, the DEP has proposed stricter standards. Pennsylvania is second only to Texas in mercury pollution it generates. Kurt Knaus, DEP's press secretary, said the state generates about five tons of mercury pollution each year, three-fourths of which comes from the state's 36 coal-fired power plants.

But state House and Senate bills, including one co-sponsored by state Sen. Mary Jo White, R-Venango County, would force the state to adopt the EPA standards in part to avoid a rise in energy costs.

Sen. White said hearings on her bill have raised doubts about mercury hot spots. She said people ingest mercury by eating fish, not by breathing it.

The state Health Department says when mercury is washed from the air by rain into streams and lakes, it is transformed to a highly toxic form that builds up in fish as it moves through the food chain. The department issues advisories that recommend restricted consumption of local fish.

There's no evidence, she said, that adopting stricter state regulations would benefit health. But there's plenty of evidence it would cause energy costs to spike.

"To put Pennsylvania under a different rule is to put the state at a competitive disadvantage," she said. "I would do this for a real benefit, but that's not what I hear. I cannot believe the stuff the DEP is putting out."

EPA's rules will reduce mercury pollution, she said, noting her hopes that her bill should be ready for a Senate vote "in a matter of weeks."

Mercury, a heavy metal, is a neuro-toxin that can create cerebral palsy, deafness and blindness in newborns and adversely affect development, motor function, language skills and verbal memory in children. It also can cause motor-skill problems, among other problems, in adults, Mr. Knaus said.

The EPA regulations, he said, would not reduce mercury emissions in Pennsylvania, prompting DEP to propose stricter regulations.

Pennsylvania is one of 20 states that have sued the EPA on claims its mercury standards violate the Clean Air Act by not considering mercury to be a hazardous toxin, Mr. Knaus said.

"Pennsylvania has a compelling case for seeking a state-specific rule that cuts mercury emissions faster and more substantially than the EPA's Clean Air Mercury Rule," the DEP news release states.

The Clean Air Council, a statewide environmental group, said House and Senate bills favoring EPA standards are "misguided."

"Blocking the implementation of Pennsylvania-specific power plant regulations would force the state to adopt much weaker federal mercury rules that would allow unsafe levels of mercury pollution to continue poisoning Pennsylvania's waterways until at least 2026," it said in a news release.

Arthur Stamoulis, the Clean Air Council's director of government affairs, said EPA's rules allow too much time for polluters to reduce mercury emissions and permit power plants to continue polluting at current levels.

EPA's rules allow pollution credits, which means a plant could continue current levels of mercury emissions if it buys credits from out-of-state plants that have reduced emissions.

If that happened, Mr. Knaus said, mercury emissions in Pennsylvania never would drop.

Rather than allow credits, the state regulations would require each plant to reduce emissions under a tighter timetable.

David Masur, director of PennEnvironment, a statewide advocacy group, said the House and Senate bills, if brought to the floor now, would produce a close vote.

But in the aftermath of Republican leaders losing elections in the primary, he said, legislators might be nervous about voting on such a controversial issue before the November election.

"The more information that comes out -- like the DEP study -- sends a clear message to elected officials that a huge problem exists and it needs to be addressed in common-sense ways," he said.