Proposed Reporting Requirements for the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6)

Public water systems (PWSs) subject to UCMR 6 (i.e., community water systems (CWSs) and non-transient non-community water systems (NTNCWSs)) will be required to take action in the EPA’s web-based reporting system, the “Safe Drinking Water Accession and Review System” (or “SDWARS 6”). Users including PWSs, laboratories, and states access SDWARS 6 through the EPA’s Central Data Exchange (CDX). SDWARS 6 will allow PWSs to review sampling locations, schedule, and results, complete responses to Data Elements, and receive automatic email reminders and notifications about their monitoring requirements. Laboratories responsible for sample analysis under UCMR 6 will submit data to SDWARS 6 on behalf of PWSs, consistent with prior UCMR cycles. States who register with CDX/SDWARS 6 will be able to view PWS monitoring schedules and sampling locations, and review data submitted by laboratories.

• CDX

PWSs that are subject to UCMR 6 are also subject to the Consumer Confidence Report (CCR) and the Public Notification (PN) rules. The CCR rule requires that community water systems (CWSs) report monitoring results when unregulated contaminants are measured at or above the UCMR 5 minimum reporting level. CWSs must report the average and range of the year’s monitoring results. Consumers interested in their CCR should contact their water supplier or may find information on how to obtain a copy of the CCR in their water bill. The PN rule requires that PWSs notify their customers that the UCMR results are available no later than 12 months after they are known. Many CWSs meet these PN requirements using their CCR, which is to be delivered to all billing customers each year by July 1. Effective in 2027, large CWSs serving more than 10,000 people are also required to deliver a second CCR, including any newly received UCMR data, by December 31. Please refer to the CCR rule and the PN rule webpages for further information.

• PWS Types

• Questions and Answers
• Proposed Data Elements for UCMR 6

Questions and Answers

What do PWSs serving 10,000 or fewer people ("small PWSs") need to do?

The EPA arranges and pays for sample analysis, and reviews monitoring results for small PWSs. After review, the EPA releases data to the small PWSs and states through SDWARS 6 followed by public release. After public release, UCMR data reside on UCMR's Occurrence Data page as part of EPA's National Contaminant Occurrence Database (NCOD).

As proposed, small PWSs notified by the EPA that they are subject to UCMR 6 participation will need to do the following:

• Establish a CDX/SDWARS 6 account before December 31, 2027, and take the following actions:
  • Read and accept their UCMR 6 Notification Letter
  • Review and, as needed, adjust sample locations
  • Add the zip codes associated with all customers in their service area
  • Review their sampling schedule
  • Provide a physical shipping address
  • Select responses to the UCMR 6 Data Elements (e.g., Disinfectant Type)
• Collect samples for UCMR 6 contaminants using sampling kits and following sampling instructions provided by the EPA's support contractor and notify the contractor of sample location changes or if unable to sample according to their original schedule
• Save the SDWARS 6 report as their official record.

What do PWSs serving more than 10,000 people ("large PWSs") need to do?

As proposed, large PWSs subject to UCMR 6 will need to do the following:

• Establish a CDX/SDWARS 6 account before December 31, 2027, and take the following actions:
  • Read and accept their UCMR 6 Notification Letter
  • Review and, as needed, adjust sample locations
  • Add the zip codes associated with all customers in their service area
  • Review their sampling schedule
  • Select responses to the UCMR 6 Data Elements (e.g., Disinfectant Type)
• Collect samples for UCMR 6 contaminants per the established schedule, and notify the EPA of sample location changes or if unable to sample according to their original schedule
• Contract with laboratories approved by the EPA for analysis of their UCMR 6 samples

Six months prior to scheduled sample collection, large ground water PWSs that wish to monitor from representative entry points to the distribution system, using the flexibility described in the proposed rule, must submit either a copy of an approved ground water representative monitoring plan (GWRMP) from a prior UCMR cycle, or a new, proposed GWRMP. Changes to sampling locations in SDWARS 6 that impact a large PWS’s GWRMP must be reported within 30 days of the change.

Large PWSs will have 30 days after their laboratory submits data to SDWARS 6 to review and approve their analytical results. If the PWS does not act on their data within those 30 days, the EPA will consider the data approved by the PWS and available to the EPA and states for review in SDWARS 6 followed by public release. After public release, UCMR data reside on UCMR's Occurrence Data page as part of EPA's National Contaminant Occurrence Database (NCOD).

What do laboratories need to do?

Laboratories approved to support UCMR 6 monitoring through the UCMR 6 Laboratory Approval Program will need to establish a CDX/SDWARS 6 account. Laboratories granted EPA approval will be obligated to report their data to SDWARS 6 within 90 days of sample collection. Laboratories can only submit data for methods for which they have received EPA approval.

What do states need to do?

States will have the opportunity to register for a CDX/SDWARS 6 account in order to view PWS monitoring schedules and sample locations, and review data in real-time prior to public release. States will be able to review PWS data in SDWARS 6 upon:

• PWS approval for results from large PWSs, and
• EPA review/approval for results from small PWSs

Proposed Data Elements for UCMR 6