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Certification of Laboratories for Drinking Water

Supplement 2 to the Fifth Edition of the Manual for the Certification of Laboratories Analyzing Drinking Water

The Long Term 2 Enhanced Surface Water Treatment Rule (LT2 Rule) (40 CFR 9, 141, 142) requires public water systems that use surface water or ground water under the direct influence of surface water to monitor their source water (influent prior to treatment) for Cryptosporidium and E. coli and turbidity (40 CFR 141.701).

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