EPA Discusses Regulatory Determination Plans with Stakeholders

On June 16th, EPA held a stakeholder meeting with water industry representatives, environmental groups, chemical and pesticide manufacturer representatives, and others (including ASDWA representatives) to discuss the progress of regulatory determinations from the third Contaminant Candidate List (CCL3).  This round of regulatory determinations is commonly referred to by EPA as “RegDet 3”.   Making regulatory determinations for contaminants on the CCL is an EPA action mandated by the 1996 amendments to the Safe Drinking Water Act (SDWA).  Under the SDWA, EPA must make a decision on at least 5 contaminants from CCL every 5 years.  However, the decision does not have to be to regulate a contaminant; EPA may also decide not to regulate the contaminant.  EPA may also defer action on the other contaminants until more information can be gathered.

EPA has reviewed data on 116 contaminants from CCL3.  Based on the information EPA has on health effects, occurrence, and other factors, EPA has narrowed this list down to 32 that may have adequate data to support a decision in this round.  From this list (shown below) EPA will make the final regulatory determinations, although EPA stressed that no final decisions have been made yet.  The “short List” of 32 contaminants being considered by RegDet3 is as follows:

Nitrosamines (5)

N-nitrosodimethylamine (NDMA)
N-Nitrosodiethylamine (NDEA)
N-Nitroso-di-n-propylamine (NDPA)
N-nitrosopyrrolidine (NPYR)
N-Nitrosodiphenylamine (NDPhA)

Inorganic Chemicals (4)
Chlorate
Molybdenum
Strontium
Vanadium

Organic chemicals (6)
1,1,1,2-Tetrachloroethane
1,2,3-Trichloropropane (TCP)
1,3-Dinitrobenzene
1,4-Dioxane
Methyl tert-butyl ether (MTBE)

Nitrobenzene
Perfluorinated Compounds (2)
Perfluorooctane sulfonic acid (PFOS)
Perfluorooctanoic acid (PFOA)

Explosives (1)
RDX

Pesticides and Degradates (14)
Dimethoate
Disulfoton
Diuron
Molinate
Terbufos
Terbufos sulfone
Acetochlor
Acetochlor ethanesulfonic acid (ESA)
Acetochlor oxanilic acid (OA)
Alachlor ethanesulfonic acid (ESA)
Alachlor oxanilic acid (OA)
Metolachlor
Metolachlor ethanesulfonic acid (ESA)
Metolachlor oxanilic acid (OA)

EPA provided stakeholders with a brief description of the data that is being reviewed for each these contaminants, including health effects data and occurrence data.  No decisions have been made by EPA for any of these contaminants and nothing was announced at the meeting.  However, the attendees speculated during discussion that EPA could make decisions not to regulate some of the organic chemicals and many of the pesticides because none had occurrence at any level of public health concern.  EPA will make its draft regulatory decisions by next year and states will have an opportunity to comment on those decisions before they are finalized in 2013. ASDWA will provide additional information as it becomes available.

For more details about the CCL and regulatory determination process, you may see EPA’s website at http://water.epa.gov/scitech/drinkingwater/dws/ccl/index.cfm.