A new report says water pollution from many of the country’s coal-fired power plants are under-regulated, and contributing to problems in already-polluted streams and rivers. Environmental groups are using the data to advocate for stricter federal regulations on power plant pollution.The report looks at all of the country’s 386 coal-fired power plants, and found that 70 percent of them have no hard limits on the heavy metals like arsenic, mercury and selenium that they discharge into waterways. A number of those are releasing pollution into rivers and streams that are already impaired by pollution.Mary Ann Hitt is the director of the Sierra Club’s Beyond Coal campaign. She said ironically, some of the pollution that used to go into the air is now being released into the water.“As we have done a better job of pulling that pollution out of the air using devices like scrubbers, then more and more toxic pollution like mercury, lead, arsenic is ending up in the solid waste that’s left behind,” she said.The Environmental Protection Agency has proposed new regulations to restrict water pollution from power plants. But the proposal includes several possible paths. Abigail Dillen of Earthjustice said signs that the EPA is willing to take action are promising, but she’s concerned the agency won’t end up implementing the most stringent regulation.“The uncertain news is whether those rules, once they’re finalized and there’s a binding deadline for their finalization in May 2014, whether the final rules will actually afford us meaningful protections,” she said.The report also alleges that the White House's Office of Management and Budget watered down the regulations before they were released to the public.