WASA Lead Test Procedure Gives False Readings, Groups Say
Friday, August 1, 2008
A group of six Washington area environmental organizations says the D.C. Water and Sewer Authority's lead-testing procedure violates federal regulations and artificially lowers lead readings. The organizations have put their complaint in a letter to the Environmental Protection Agency.
High lead levels affected the District's water in 2002, 2003 and 2004, and WASA was criticized for not publicizing tests that showed there was a problem. A chemical added to the water supply in 2004 reduced lead corrosion, and WASA's tests since then have shown that the city's lead levels have been within EPA guidelines.
But a part of the testing added in 2005 could result in falsely rosy data, the organizations said.
The environmentalists object to home-testing instructions to run water for 10 minutes six to eight hours before testing lead levels. That pre-flush of the system eliminates water that has been sitting in the city service line from the street, a key source of lead in Washington's household drinking water, the environmentalists said.
"It's just a blatant disregard for scientific evidence," said Yanna Lambrinidou, president of Parents for Nontoxic Alternatives, one of the letter signers. "WASA's compliance with federal water safety standards at this point depends on cleaning peoples' lead service lines and pipes the night before they sample for lead."
In 2004, WASA told District residents that running taps for 10 minutes was an effective way of cleaning lead from drinking water.
WASA officials say they are trying to ensure standardization of the data they collect.
"If you're gone for the weekend, then the lead levels would typically be higher," said Maureen Donnelly, supervisor of WASA's Water Quality Division. "We want to get samples that represent the same premise . . . that water has sat in the pipe for at least six to eight hours."
Lead leaches into the water during the hours the water sits in pipes, Donnelly said.
But some lead experts found the testing procedure problematic.
"If you wanted to find a lead problem, this is not what you would do," said Marc Edwards, a Virginia Tech professor of civil and environmental engineering and a 2007 MacArthur Fellow who has studied the lead levels in the District's water. "If you wanted to hide a lead problem, this is what you would do.
"It removes all traces of lead that would come from the lead service line," Edwards said. "If they had used this instruction in 2004" -- when tests showed dangerously high levels of lead in many residents' water -- "they would have missed the problem."
Baltimore also tests lead levels in home water supplies, but it does not do pre-flushing. Brooks Baker, a spokesman for the Los Angeles Department of Water and Power, wrote in an e-mail that regulations there specifically forbid the use of pre-flushing.
The EPA requires that "worst-case" lead levels be measured in water but does not detail how to find those conditions and does not specifically forbid a pre-flush of the water.
"Neither the lead and copper rule or the guidance really addresses flushing prior to stagnation," said David Sternberg, a spokesman for EPA Region 3, the division that oversees the District. "We've neither approved nor disapproved that sampling."
Sternberg said WASA submits its sampling plans to the EPA for review. "I think it's safe to say that if EPA had a problem with it, there would have been comment," Sternberg said.