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NH Proposes Lower Arsenic Drinking Water Standard

Last Friday (1/4), the New Hampshire Department of Environmental Services (NHDES) submitted a report to its legislature that recommended lowering the arsenic drinking water standard in NH from 10 ppb (the current EPA standard) to 5 ppb. This report was driven by legislation in 2018 that required NHDES to review the arsenic standard and to submit the report by January 1, 2019. New Hampshire now joins New Jersey as the second state with an arsenic standard of 5 ppb.

EPA revised its arsenic standard in January 2001, lowering the standard from 50 ppb to 10 ppb. Given the turnover in Administration in January 2001, EPA conducted a detailed review in 2001, including three expert panel reviews, and the lower standard held up to the scrutiny of that review. The revised arsenic rule is one of the two times (uranium being the other time) EPA has used Section 1412(b)(6) of the Safe Drinking Water Act (SDWA) that allows the Agency to set the standard at a level where the benefits justify the costs, and not set the standard based solely on feasibility. EPA’s 258-page Economic Analysis for the Arsenic Rule from 2000 provides the details of the benefit-cost analysis used in making that decision.

The NH report is an interesting read for those are that are interested in how drinking water policy works in NH as compared to national water policy decisions at EPA – it’s a solid analysis. The page below summarizes the impacts from the lower standard – essentially that the absorptive media needs to be replaced more frequently. Bed life is reduced from 40,000 to 20,000-bed volumes with the lower standard of 5 ppb, and the annual maintenance cost is 97.5% of the total cost due to more frequent media replacement.

NH arsenic treatment costs