Framework Established for New Drinking Water Regulations
Tobey, Bruce, Nation's Cities Weekly
After 20 months of negotiation and deliberation, a Federal Advisory Committee (FAC) appointed by the Environmental Protection Agency (EPA), and on which I served on behalf of NLC, has reached agreement on the framework for a new round of national drinking water regulations.
With the concurrence of NLC President, Bob Knight, I signed that agreement on September 26. NLC thereby joined 20 other groups(**) in support of new rules governing disinfection by-products (DBPs) and pathogens, such as Cryptosporidium, that may occur in public drinking water supplies.
DBPs are contaminants that some scientists believe may cause cancer. They are formed when chemicals used to disinfect our water supplies, such as chlorine, chloramines, and chlorine dioxide, combine with naturally occurring organic materials, such as dead leaves, which are also found in those same water supplies. By managing the application of chemical disinfectants and using watershed protection of filtration to remove organic materials, water suppliers try to reduce DBP levels.
On the other hand, the use of disinfectants is a critical tool for combating many microbial pathogens, which can cause severe illness or even death. But Cryptosporidium presents particularly difficult problems--while it can pose huge health risks (a 1994 Cryptosporidium outbreak in Milwaukee killed 100 people and caused severe illness in 400,000 others), particularly for people with compromised immune systems, it is hard to measure and even harder to fight.
Through the 1996 Amendments to the Safe Drinking Water Act, Congress required EPA to issue regulations that would protect the American public from both microbial contaminants and DBPs. To develop this rule, EPA had to balance two risks: the potential cancer risk of DBPs had to be weighed against the proven risk of illness, or even death, from exposure to Cryptosporidium and other pathogens.
To deal with this challenge--how to reduce DBP occurrence without simultaneously increasing the risk of microbial contamination in the nation's public drinking water supplies--EPA convened the FAC in January 1999, with NLC at the table to represent the interests of the nation's cities and towns.
The FAC was not writing on a blank slate. A previous advisory group, the Stage 1 Disinfectants/Disinfection By-Products Advisory Committee, met from 1992-1994 and developed initial protocols to address these concerns. This group's work yielded Stage 1 Rules, promulgated in November 1998, with
--requirements to enhance the removal of natural organic materials in source water (primarily surface water supplies);
--federal standards, known as Maximum Contaminant Levels (MCLs), for disinfection by-products; and,
--turbidity standards, which provided a surrogate for controlling the tough-to-measure Cryptosporidium.
Both the Stage 1 negotiators and their successors in a subsequent regulatory revision concluded that scientific evidence was inadequate to warrant more stringent measures. They left behind a recommendation, however, that the FAC, which convened in January 1999, should rely on new monitoring data and scientific evidence gathered in the interim.
The agreement reached by the FAC reflects:
--the need to reduce certain DBPs--Total Trihalomethanes and Haloacetic Acids--by altering the way compliance with the current federal standards is measured and calculated - even though scientific evidence remains weak regarding both the link between DBPs and cancer as well as newer concerns that DBPs might have adverse reproductive and developmental impacts; and
--the need for additional monitoring for Cryptosporidium and E. coli, which will lead to determinations as to whether (and what) future treatment will be necessary.
In summary the agreement which I signed for NLC supports rules which:
--require evaluation of drinking water distribution systems;
--maintain the current federal standard for DBPs;
--require new monitoring for Cryptosporidium and more extensive monitoring for DBPs. …