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Drinking Water Requirements for States and Public Water Systems

Stage 1 and Stage 2 Compliance Help for Community Water System Owners and Operators

Complying With the Stage 1 Disinfectants and Disinfection Byproducts Rule: Basic Guide

The Stage 1 DBPR applies to PWSs that add a chemical disinfectant. EPA has developed three documents to address the requirements of the Stage 1 DBPR:

The Basic Guide – for CWSs and NTNCWSs that add a chemical disinfectant and serve fewer than 10,000 persons.

Supplement A – for CWSs, NTNCWSs, and transient non-community water systems (TNCWSs) that use chlorine dioxide and CWSs and NTNCWSs that use ozone.

Supplement B – for Subpart H CWSs and NTNCWSs that add a chemical disinfectant and use conventional filtration.

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Operational Evaluation Guidance Manual

This manual assists PWS in meeting requirements for operational evaluations under the Stage 2 DBPR. The manual provides guidance for documenting and reporting an operational evaluation level (OEL) exceedance.

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Simultaneous Compliance Guidance Manual for Stage 2 Rules

This manual discusses issues that PWSs will face as they evaluate and implement rules simultaneously. It discusses changes necessary to comply with the Stage 2 DBPR and the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR). It also covers how to maintain compliance with earlier rules such as the Total Coliform Rule and Lead and Copper Rule.

EPA has developed this guidance manual to provide PWSs and states with information on operational and capital changes and approaches to enable PWSs to evaluate different compliance strategies and technologies.

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Consecutive Systems Guidance Manual for the Stage 2 DBPR

This manual discusses requirements for consecutive systems to comply with Stage 2 DBPR monitoring and maximum contaminant level (MCL) requirements. Consecutive systems are PWSs that receive treated water from other PWSs. Most previous drinking water rules have not specifically addressed requirements for consecutive systems to comply with.

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Complying with the Stage 2 Disinfectants and Disinfection Byproducts Rule: Small Entity Compliance Guide

This manual contains an introduction for the Stage 2 DBPR. It describes the requirements of the Rule that apply to small systems (serving fewer than 10,000 people). It also provides step-by-step guidance on how to comply with Stage 2 DBPR requirements.

Quick Reference Guides

Additional quick reference materials (e.g., Stage 1 and Stage 2 Comprehensive Disinfectants and Disinfection Byproducts Rules Laboratory Quick Reference Guide).

For more information, please see the Stage 1 & Stage 2 Disinfectants And Disinfection Byproducts Rules page.

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