The Pentagon has officially declared victory over the Environmental Protection Agency in the battle over perchlorate, a toxic ingredient in rocket fuel that now contaminates water in 35 states.
After losing a prolonged debate with the Department of Defense last year over the level at which perchlorate should be considered dangerous, the EPA last week issued guidance saying cleanup of contaminated sites is needed only if perchlorate levels in water exceed 24.5 parts per billion, far above the 1 ppb limit EPA first proposed in 2002. Some state regulators believe the new federal standard is dangerously lenient.
As soon as the EPA released its new guidance, the Pentagon put the higher limit into effect by issuing its own new policy. As a result, DoD is now likely to avoid cleanups at hundreds of sites, including many old firing ranges, where perchlorate levels are below 24.5 ppb.
The actions had been anticipated since early last year, when a National Academy of Sciences panel backed up a Pentagon challenge that said EPA’s proposed perchlorate limit of 1 ppb was too stringent.
The DoD had cited studies by its own scientists showing perchlorate to be harmless at levels as high as 200 ppb. The academy panel didn’t go that far, but did say a person could safely drink water with perchlorate levels of 24.5 ppb before the chemical begins to disrupt thyroid functions. The EPA accepted the panel’s conclusion and adopted that level as the cleanup trigger.
Some say the EPA surrendered too quickly on perchlorate. The suggest that focusing exclusively on perchlorate levels in water in insufficient since people are also exposed to the chemical in food. Nearly all lettuce grown in California, for instance, contains traces of perchlorate from the water used to irrigate farmlands there. To address this problem, regulators in California and Massachusetts are considering adopting limits of 6 ppb and 1 pbb, respectively.
Sen. Dianne Feinstein, D-Calif., was quick to point that out in blasting the EPA’s new perchlorate limit last week. “This preliminary standard is unacceptable and could put the health of thousands of Americans at risk,” Feinstein said. “It also ignores perchlorate contamination in food.”
