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EPA Revises E. coli Drinking Water Rule


By Bingham Greenebaum Doll LLP

On December 20, 2012, EPA Administrator, Lisa Jackson, signed the National Primary Drinking Water Regulations: Revisions to the Total Coliform Rule (RTCR).  The rule applies to all public water systems including public and privately owned community, transient non-community, and non-transient non-community water systems.  This includes municipal water systems as well as water systems in mobile home parks, day care centers, churches, schools, and homeowner’s associations.  The RTCR is an update to the Total Coliform Rule (TCR) which was first adopted in 1989.  EPA says the revisions to the rule will offer an opportunity for greater public health protection while reducing the implementation burden and improving the rule’s effectiveness.

The 1989 TCR set the drinking water Maximum Contaminant Level (MCL) based on total coliforms, including fecal coliforms, rather than E. coli specifically.  It also established Maximum Contaminant Level Goals (MCLG) for total coliforms to protect public health.  Public water systems were required to regularly monitor and report coliform levels to the public, but there was no requirement to investigate or remediate the cause of the contamination.  While fecal coliforms, particularly E. coli, are known to cause gastrointestinal illness, many other forms of coliform bacteria are harmless and are not a good indicator of fecal contamination in drinking water systems.

There are four categories of violations under the RTCR: (1) E. coli MCL Violations; (2) Treatment Technique Violations; (3) Monitoring Violations; and (4) Reporting Violations.

E. coli MCL Violations.  Under the RTCR, total coliform levels now serve only as an indicator of a potential pathway of contamination into a drinking water system, and not an MCL violation.  If a routine sample tests positive for total coliforms, a water system must collect more samples, investigate to determine if a sanitary defect is causing the contamination and repair it as necessary.  If a routine sample tests positive for total coliforms and is followed by a repeat sample that tests positive for E. coli, an E. coli MCL violation occurs.  If an initial sample tests positive for E. coli and is followed by a repeat sample that tests positive for total coliforms, an E. coli MCL violation occurs.  Failing to take repeat samples after detecting E. coli or total coliforms also constitutes an E. coli MCL violation.

Treatment Technique Violations.  A treatment technique violation occurs when a system exceeds a treatment technique trigger and fails to conduct the required assessment or when a seasonal systems fails to complete a state-approved start-up procedure prior to serving water to the public.

Monitoring Violations.  A monitoring violation occurs when a system fails to take a routine sample during a compliance period or fails to analyze for E. coli following a total-coliform positive routine sample.

Reporting Violations.  A reporting violation occurs when a system fails to submit a monitoring report or completed assessment report.  A violation also occurs when a system fails to report an E. coli positive sample in a timely manner.  Seasonal systems are subject to a reporting violation if they fail to submit certification of completion of a state-approved start-up procedure.

Under the RTCR, monitoring frequency can be reduced for small, well-operated systems with a good history of coliform-free operation, while high-risk systems with a history of contamination will be subject to a more stringent monitoring schedule.  The RTCR requires water systems to notify the public only when a violation of an E. coli MCL occurs, eliminating the former requirement to report total coliforms monthly.  A system must also report if it detects total coliforms, but fails to conduct the required assessment and corrective action.  The RTCR adds monitoring requirements for seasonal systems such as campgrounds and state and national parks not covered under the 1989 TCR.

The RTCR becomes effective 60 days after publication in the Federal Register.  Public water systems will have until April 1, 2016 to comply with the new rule.  More information on the rule can be found at

To view a complete PDF of the November/December 2012 issue of the Environmental Letter, click HERE.

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