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Drinking Water Requirements for States and Public Water Systems

Optimal Corrosion Control Treatment Evaluation Technical Recommendations

This document provides technical recommendations that both systems and primacy agencies can use to comply with Lead and Copper Rule (LCR) corrosion control treatment requirements and to evaluate and designate optimal corrosion control treatment (OCCT) more effectively.  The appendices include OCCT evaluation templates that can be used to organize data and document decision-making. For added customizability and convenience, these templates are also availabile in a spreadsheet format.

The update addresses common technical questions and clarifies that the recommendations are provided as generalized guidelines. Specific values identified in the recommendations are not intended to be interpreted or prescribed universally as default minimums or maximums. Individual system characteristics (e.g., water quality, distribution system configuration, lead and copper sources, etc.) may warrant other alternatives or values that are distinct from the manual.

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