Frequent Questions

Are IDSE results required to be reported in CCRs? If so, is this monitoring used for compliance purposes?

Yes, results must be included in CCRs, but are not used for determing compliance with the MCLs.  Systems can include an explanation of IDSE sampling in their CCRs if they choose to do so.

For additional guidance on the Stage 2 Disinfectants and Disinfection Byproducts rule please visit

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