Wednesday, January 03, 2007

Boxer & AWWA Differ On Monitoring For Perchlorate

Dec 22: U.S. Senator Barbara Boxer (D-CA), incoming Chair of the Senate Environment and Public Works Committee, issued a statement on EPA’s final rule which will require monitoring drinking water for up to 25 unregulated chemicals under the Unregulated Contaminant Monitoring Rule (UCMR2) [See WIMS 1/2/06]. Boxer said the rule will not require testing drinking water for the toxic chemical perchlorate. She said the toxin has been found in millions of Americans’ drinking water. EPA’s original 1999 rule ordered testing for perchlorate, and just last year EPA proposed to extend that requirement. However, she indicated in a release that, in the wake of industry opposition, the new final rule says that “based on public comment and further consideration, EPA has removed the requirement for monitoring perchlorate….”

The Senator said, “I am distressed that the agency has said there will be no required testing of our drinking water for the dangerous chemical perchlorate. This is another unwelcome holiday gift from EPA to the American public, one of several recent EPA actions undermining health protection. As a result of this new rule, Americans will not have up-to-date information on whether their tap water is contaminated with this toxin. I also remain deeply concerned that EPA has dragged its feet and refused to set a safety standard for perchlorate in our drinking water. Until EPA sets a standard, at the very least we should know if it's in our drinking water. We will not let this kind of action stand. We will closely examine this issue when the new Congress convenes.”

An October 21, 2005, letter from the American Water Works Association (AWWA), representing 4,200 utilities that supply roughly 80 percent of the nation's drinking water, commenting on the regulation indicated, "...we have significant concerns with an apparent disconnect between the CCL [Contaminant Candidate List] and the UCMR and the inclusion of perchlorate in the proposed UCMR2... AWWA recommends that perchlorate not be included in the final UCMR2. The perchlorate monitoring is unnecessary and will not provide meaningful data that for any regulatory decisions for any potential perchlorate drinking water regulation."

AWWA argued that, "The National Academy of Sciences’ (NAS) National Research Council (NRC) conducted a review of the health effects of perchlorate and concluded that a daily ingestion of up to 0.0007 milligrams per kilogram of body weight can occur without adversely affecting the health of even the most sensitive populations. EPA translated this to a Drinking Water Equivalent Level (DWEL) of 24.5 ug/L, assuming a 70 kg body weight and 2 L per day consumption.

"Based on our evaluation of the current regulatory data, it does NOT appear that any potential perchlorate regulation would be below 4 ppb, which was the UCMR1 minimum reporting level. Therefore, the monitoring requirement for perchlorate in the proposed UCMR2 is duplicative and unnecessary, and would be an inappropriate use of utilities’ limited resources. Requiring utilities to spend more than $4 million to obtain perchlorate occurrence data that is not needed for regulatory development is not justified. EPA already has a large, robust occurrence database above 4 ppb from UCMR1, and this occurrence database is adequate for a regulatory determination for perchlorate."

Access the statement from Senator Boxer (
click here). Access an overview of the UCMR2 from AWWA regulations (click here). Access the AWWA comment letter of 10/21/05 (click here). Access an EPA release (click here). Access a pre-publication copy of the final rule (click here). Access EPA's UCMR 2 website for extensive information (click here). [*Drink]