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Drinking Water Analytical Services

Stage 2 DBPR

The Environmental Protection Agency's Stage 2 Disinfectants and Disinfection Byproducts Rule (Stage 2 DBPR) is designed to help reduce the levels of TTHM and HAA5 in distribution systems. The rule affects community water systems (CWSs) and nontransient noncommunity water systems (NTNCWSs) that add a primary or residual disinfectant other than ultraviolet light, or deliver water that has been treated with a primary or residual disinfectant other than ultraviolet light.

Some affected systems are subject to an Initial Distribution System Evaluation (IDSE), which is used to determine Stage 2 monitoring locations. IDSEs are required by all affected CWSs and NTNCWSs that serve at least 10,000 people.

All systems affected by the Stage 2 DBPR are required to submit Stage 2 compliance monitoring plans. These plans must include recommendations on a compliance monitoring schedule and sampling locations.

Your Stage 2 DBPR Compliance Partner

UL offers the services and expertise to help you comply with Stage 2, including determining your system's compliance schedule and IDSE requirements.

We take pride in both our technical expertise to analyze for disinfection by-products and our in-depth understanding of Stage 2's complex requirements.

This knowledge allows us to serve as a resource for our clients as they develop and implement their monitoring schedules. It also provides our clients and regulatory agencies with confidence that the data we generate will meet Stage 2's compliance requirements.

Results generated by our laboratory are automatically uploaded to the EPA's LT2/Stage 2 Data Collection & Tracking System (DCTS) as required by the rule. Once the results have been posted, they are available for your system to approve.

We look forward to assisting you in complying with Stage 2 DBPR.

Additional Resources

Please use the following resources for more information on the Stage 2 rule:

To learn about how UL can help you meet other drinking water regulations, please visit the following pages:

Contact Us

For more information on UL's drinking water analytical services you may email us or call +1-800-332-4345. You may also wish to visit our FAQs.