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Initial Review for Existing Drinking Water Standards

An initial review is conducted to identify contaminants for which a detailed technical review would not be appropriate in the current review cycle. The following conditions may eliminate a contaminant from further consideration during the current review cycle:

Excluding such contaminants from subsequent steps in the Six-Year Review improves the efficiency and effectiveness of the review process. It prevents duplicative efforts for recent or current regulatory actions in progress to revise specific national primary drinking water regulations. It also avoids recommendations based on inadequate information for contaminants with ongoing or pending health risk assessments that already have MCLs set equal to their respective MCLGs.