EPA confirms perchlorate decision

WASHINGTON -- Federal regulators said Friday they don't plan to try to rid drinking water supplies of a toxic rocket fuel ingredient that's been found in 35 states.

The Environmental Protection Agency will take public comment for 30 days before finalizing its decision not to regulate the contaminant, perchlorate, in drinking water. News outlets reported the agency's plans last month based on internal EPA documents.

The announcement Friday provoked outrage from Democratic lawmakers and a lawsuit threat from environmental groups. Particularly widespread in California and Texas, perchlorate has been found to interfere with thyroid function and pose developmental health risks, particularly for babies and fetuses.

"EPA's decision has industry's fingerprints all over it. Weapons makers will benefit at the expense of millions of Americans," said Earthjustice attorney George Torgun.

He said Earthjustice would argue in court that perchlorate does qualify for regulation under the Safe Drinking Water Act.

Ammonium perchlorate was first detected in Lake Mead 11 years ago, downstream from facilities near Henderson that manufactured the compound that is used as an oxidizer for rocket fuel.

Lake Mead is the primary drinking water supply for Southern Nevada.

While perchlorate can't be removed through conventional filtration or ozonation processes at water treatment plants, a system has been set up to intercept and extract it before it enters the Las Vegas Wash, which empties into Lake Mead. As a result, perchlorate levels in water drawn from Lake Mead have dropped dramatically in recent years.

The level in local treated drinking water in 2007 was less than even the most stringent state standard of 2 parts per billion adopted by Massachusetts in the absence of a federal limit. One part per billion is about the same as one drop of water in an Olympic-size swimming pool.

The decision on perchlorate has been pending for years as the Pentagon tussled with the EPA over the issue.

The Defense Department used perchlorate for decades in testing missiles and rockets, and most perchlorate contamination is from defense and aerospace activities, congressional investigators have said.

The Pentagon could face liability if the EPA set a national drinking water standard that forced water agencies around the country to undertake costly cleanup efforts. But Pentagon officials have insisted they did not seek to influence the EPA's decision.

States already have moved ahead with their own drinking water standards, with California setting a limit of 6 parts per billion and Massachusetts setting it at 2 parts per billion.

EPA officials said in a news release Friday that the agency had determined that in more than 99 percent of public drinking water systems, perchlorate was not at levels of public health concern.

Review-Journal writer Henry Brean contributed to this report.