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Revised Total Coliform and Groundwater Rule (RTCR)

Groundwater Rule

Summary

The intent of the Groundwater Rule (GWR) is to provide for increased protection against microbial pathogens in public water systems that use ground water sources. The GWR was written with particular concern about those ground water systems that are susceptible to fecal contamination since disease-causing pathogens may be found in fecal contamination.

The GWR applies to public water systems that serve ground water. The Rule also applies to any system that mixes surface and ground water if the ground water is added directly to the distribution system and provided to consumers without treatment.

Rule

Additional Resources

Revised Total Coliform Rule (RTCR)

On February 13, 2013, the Environmental Protection Agency (EPA) revised the 1989 Total Coliform Rule in an effort to provide greater public health protection. The revisions, based on recommendations from a federal advisory committee, are known as the Revised Total Coliform Rule or RTCR.

The RTCR establishes a maximum contaminant level (MCL) for E. Coli and uses E. Coli and total coliforms to initiate a “find and fix” approach to address fecal contamination that could enter into the distribution system. It requires public water systems to perform assessments to identify sanitary defects and subsequently take action to correct them.

Beginning April 1, 2016, all public water systems were required to be in compliance with the RTCR.

Following are guidance documents, forms, and links to resources intended to help Maine public water systems understand and comply with the requirements of the RTCR.

Quick Reference Guides

Startup Procedures (seasonal water systems only)

Under the RTCR, seasonal water systems must conduct a State-approved startup procedure at the beginning of each operating period, before serving water to the public. Seasonal water systems must also certify that they have completed the state-approved startup procedure. The startup procedure must be completed — with certification submitted to the Drinking Water Program — before a PWS opens and begins operating for the season.

For example, if a seasonal public water system opens on May 1, start-up procedures must be completed and the certification form provided to the DWP before May 1 of that year.

Approved Start-up Procedures:

Sampling Site Plans

The RTCR requires that total coliform samples be collected by public water systems at sites that are representative of water quality throughout the distribution. Sampling locations must correspond with those identified in a written sampling site plan that is subject to State review and approval. Sample site plan requirements under the RTCR include, but are not limited to, establishing sample site locations for routine total coliform samples, repeat total coliform samples, raw water samples, and follow-up total coliform samples. Sample site plans must also identify when samples will be taken during the compliance period.

For public water systems serving a population of 1,000 or fewer: Public Water System Inspectors will review and work with public water systems to create or modify sample site plans that meet the guidelines set forth in the RTCR during routine sanitary surveys or on-site visits.

Sampling Site Plan Approval Checklists:

Protected Source

Determining whether a public water system has a “protected source” is important under the Revised Total Coliform Rule, as it can impact whether some water systems are eligible for reduced monitoring of Total Coliform bacteria. Similarly, for water systems that have a default monitoring frequency of quarterly for Total Coliform but have been increased to monthly due to a compliance trigger, source protection status is important for determining eligibility to return to a quarterly monitoring frequency.

RTCR: Assessments and Corrective Actions

The RTCR requires public water systems that have an indication of Total Coliform bacteria contamination (e.g., as a result of TC+ samples, E. coli MCL violations, performance failure) to assess the problem and take corrective action. There are two levels of assessments (Level 1 and Level 2) based on the severity or frequency of the problem. Public water systems that have multiple positive total coliform bacteria sample results are required to conduct a ‘Level Assessment’, an in-depth assessment of their water system to identify problems and determine appropriate corrective actions. There are two levels of assessment — Level 1 and Level 2 — based on the severity or frequency of the problem.

Triggering an Assessment

Level 1 Assessments are triggered by:

  • 2 or more TC+ routine/repeat samples in the same month OR for systems collecting 40 or more samples each month: greater than 5% of routine/repeat samples positive
  • Failure to take required repeat sample(s) after any single TC+

Level 2 Assessments are triggered by:

  • E. coli MCL violation
  • Second trigger of a Level 1 Assessment within a rolling 12-month period

Conducting an Assessment

Level 1 Assessments can be performed by:

  • For public water systems NOT required to have a licensed operator: Public water system owner or responsible party or DWP personnel or approved entity.
  • For public water systems required to have a licensed operator: A licensed operator at a grade comparable to or higher than the grade of the public water system or DWP personnel or approved entity.

Level 2 Assessments can be performed by:

  • For public water systems NOT required to have a licensed operator: A licensed operator holding both a Class II Treatment and Class I Distribution license or higher or DWP personnel or approved entity.
  • For public water systems required to have a licensed operator: A licensed operator holding a license with treatment and distribution classes equal to or higher than that of the PWS, at a minimum Class II Treatment and Class I Distribution, or DWP personnel or approved entity.
  • Companies or Operators Willing to Perform Level 2 Assessments for a Fee (PDF)

Corrective Actions

When sanitary defects are identified during a Level 1 or Level 2 Assessment, they should be corrected as soon as possible to protect public health. The PWS must complete correct actions by one of the following timeframes:

  • No later than the time the assessment form is submitted to State, which must be within 30 days of triggering the assessment, or;
  • Within a state-approved timeframe which was proposed in the assessment form.

Assessment Forms

Additional Resources