Eleven contaminants under a national primary drinking water regulation (NPDWR) pursuant to the Safe Drinking Water Act (SDWA) wont be regulated by the U.S. Environmental Protection Agency (EPA), it announced on May 1 (see 72 Fed. Reg. 24016). A decision not to regulate a contaminant isnt typical, but under this particular program, its not unheard of.
How EPA decides
Every five years, the SDWA requires EPA to decide whether to regulate at least five so-called unregulated contaminants with an NPDWR. Candidate contaminants are drawn from the Contaminant Candidate List (CCL), which EPA must publish every five years. The CCL is a long list of contaminants that arent subject to any proposed or final NPDWRs and are either known or expected to be found in public water systems, and thus may require regulation under the SDWA.
If EPA determines that a CCL contaminant may have an adverse effect on human health, its known to occur or theres a substantial likelihood that it will occur in public water systems with a frequency and at levels likely to cause public health concerns, and in EPAs judgment regulation of such a contaminant would reduce public health risk, then EPA must publish a Maximum Contaminant Level Goal (MCLG) and issue an NPDWR for the contaminant.
An MCLG is the maximum level of a contaminant in drinking water at which no known or anticipated adverse effect on the health of persons would occur, and which allows a margin of safety. MCLGs are largely advisory as theyre legally unenforceable. An NPDWR is a legally enforceable standard that applies to public water systems. These standards set legal limits, called maximum contaminant levels (MCL), or identify a specific treatment technique for public water systems for a specified contaminant or group of contaminants.
Compiling the list
EPA formed the National Drinking Water Advisory Council (NDWAC) shortly after the 1996 SDWA Amendments were enacted to provide input on what contaminants should be on the CCL. EPA published the final CCL in 1998, which contained 50 chemical and 10 microbiological contaminants. EPA published preliminary regulatory determinations for a subset of these 60 contaminants in 2003, identifying nine contaminants that had sufficient data and information to make regulatory determinations.
These included: Acanthamoeba, aldrin, dieldrin, hexachlorobutadiene, manganese, metribuzin, naphthalene, sodium, and sulfate. EPA also decided that the establishment of an NPDWR wasnt needed for any of them. EPA did, however, issue guidance on Acanthamoeba and health advisories for magnesium, sodium, and sulfate.
EPA issued CCL2 in 2004, with 51 contaminants carried forward from CCL1. Of these, EPA took action on 11: boron, dacthal di-acid degradate, dacthal mono-acid degradate, DDE, 1,3-dichloropropene (telone), 2,4-dinitrotoluene, 2,6-dinitrotoluene, EPTC, fonofos, terbacil, and 1,1,2,2-tetrachloroethane. As noted, based on the data and information on which it relied, EPA decided that an NPDWR wasnt appropriate for any of them. The Federal Register notice outlines in significant detail the decision-making process that EPA used. EPA also solicited comment on its decision, which were due by July 2.
Monitor the list
EPAs CCL process affects many stakeholders with different and sometimes competing interests. For contaminant manufacturers (or manufacturers of substances that form a degradate), CCL inclusion is clearly not good news. EPA offers opportunities for public comment on any decision to regulate or not; manufacturers and others should avail themselves of such opportunities to correct the record or otherwise advocate that no NPDWR is needed. An EPA decision to establish an NPDWR poses formidable commercial challenges to any product thats found to occur in ground water/drinking water supplies at levels believed to pose a public health threat.
For technology manufacturers, knowledge of the CCL and EPAs schedule for reviewing contaminant candidates is important. Contaminant removal/abatement technology will be in demand for any contaminant that EPA determines needs regulation in the SDWA. For this reason, these manufacturers should monitor EPAs scheduled reviews of contaminants.
Others, including regulatory experts, lawyers, citizen activists, state and local regulators, also have a stake in this important regulatory process. To stay abreast of these developments, and participate as necessary, EPAs website offers useful information at http://www.epa.gov/safewater.
By Lynn Bergeson, regulatory editor. She is managing director of Bergeson & Campbell, P.C., a Washington, D.C.-based law firm that concentrates on chemical industry issues. Contact her at firstname.lastname@example.org. The views expressed herein are solely those of the author. This column is not intended to provide, nor should be construed as, legal advice.