The Environmental Protection Agency has proposed new rules to safeguard drinking water from byproducts formed during chemical disinfection and a parasite spread by human and animal waste.
EPA officials also decided against adding more contaminants to the list of about 90 that the government already regulates in drinking water. The agency concluded that for nine of 60 unregulated contaminants there was no need to create new drinking water standards. The other 51 contaminants are still being studied.
Environmentalists raised concerns Tuesday that perchlorate, a toxic part of solid rocket fuel that has contaminated water supplies in at least 22 states, wasn't among the contaminants whose studies were completed first. EPA is required by Congress only to study at least five unregulated contaminants every five years.
At that rate, according to water experts at the Natural Resources Defense Council, EPA probably will not issue any new enforceable standards for perchlorate - or any other of the unregulated contaminants - until at least 2010.
One of the EPA rules proposed Friday would require communities to improve their water treatment plants' ability to monitor for and protect against cryptosporidium, a waterborne parasite that killed 100 people in Milwaukee in 1993 but is most common in developing countries.
Water systems would also be required to use better filters or create buffer strips to protect watersheds. Annually, EPA estimates, that would add up to $1.68 to the average household's yearly water bills.To guard against disinfection byproducts, which form when organic matter reacts with chorine and other disinfectants added to reduce microbes, EPA would require water treatment systems to monitor and document where the highest concentrations are in their pipelines.
Both rules would take effect by mid-2004.