Six-Year Review 3 of Drinking Water Standards
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EPA announced the review results for the Agency’s third Six-Year Review (called Six-Year Review 3). Based on the Agency's detailed review of 76 national primary drinking water regulations (NPDWRs), EPA concluded that eight NPDWRs are candidates for regulatory revision. The eight candidates are Chlorite, Cryptosporidium (under the SWTR, IESWTR and LT1), Haloacetic acids, heterotrophic bacteria, Giardia lamblia, Legionella, Total Trihalomethanes, and viruses (under the SWTR). These eight NPDWRs are included in the:
- Stage 1 and Stage 2 Disinfectants and Disinfection Byproducts Rules
- Surface Water Treatment Rule
- Interim Enhanced Surface Water Treatment Rule
- Long Term 1 Enhanced Surface Water Treatment Rule
EPA determined that for the contaminants regulated under these rules there is new information on health effects, treatment technologies, analytical methods, occurrence and exposure, implementation and/or other factors that provide a health or technical basis to support a regulatory revision that will improve public health protection. This announcement is not a regulatory decision. Instead, it initiates a process that will involve more detailed analyses of health effects, analytical and treatment feasibility, occurrence, benefits, costs and other regulatory matters relevant to deciding whether a rulemaking to revise a regulation should be initiated. EPA is seeking public comment and information to help inform potential regulatory revisions for the eight candidates. Read more about these activities.
In addition to the 76 NPDWRs, this review included 12 other NPDWRs that did not need a detailed review because of recent, ongoing, or pending regulatory actions. Those contaminants having recent or ongoing regulatory actions are: lead, copper, total coliforms (under ADWR and RTCR), E. coli, and eight carcinogenic volatile organic compounds (cVOCs).