Proposed Ground Water Rule

EPA is proposing a rule which specifies the appropriate use of disinfection in ground water and addresses other components of ground water systems to assure public health protection.  The Ground Water Rule (GWR) establishes multiple barriers to protect against bacteria and viruses in drinking water from ground water sources and will establish a targeted strategy to identify ground water systems at high risk for fecal contamination.  The GWR is scheduled to be issued as a final regulation in Spring 2003.

Background

Although ground water has historically been thought to be free of microbial contamination, recent research indicates that some ground waters are a source of waterborne disease.  Most cases of waterborne disease are characterized by gastrointestinal symptoms (diarrhea, vomiting, etc.) that are frequently self limiting in healthy individuals and rarely require medical treatment.  However, these same symptoms are much more serious and can be fatal for persons in sensitive subpopulations (such as, young children, elderly and persons with compromised immune systems).  In addition, research indicates that some viral pathogens found in ground water are linked to long term health effects (for example, adult onset diabetes, myocarditis).  EPA does not believe all ground water systems are fecally contaminated; data indicate that only a small percentage of ground water systems are contaminated.  However, the severity of health impacts and the number of people potentially exposed to microbial pathogens in ground water indicate that a regulatory response is warranted. 

Presently, only surface water systems and systems using ground water under the direct influence of surface water are required to disinfect their water supplies. The 1996 amendments to the Safe Drinking Water Act require EPA to develop regulations that require disinfection of ground water systems “as necessary” to protect the public health (§1412(b)(8)). The proposed GWR will specify when corrective action (including disinfection) is required to protect consumers who receive water from ground water systems from bacteria and viruses.

This rule applies to public ground water systems (systems that have at least 15 service connections, or regularly serve at least 25 individuals daily at least 60 days out of the year). This 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.  The GWR does not apply to privately owned wells, however, EPA recommends private well owners test for coliform bacteria once each year. 

While developing the proposal, EPA consulted extensively with stakeholders.  EPA benefited from the stakeholders’ participation in four public meetings across the country, and their comments are reflected in the proposed rule.  EPA also received valuable input from small entity representatives as part of the Small Business Regulatory Enforcement Fairness Act (SBREFA) panel.  The GWR Small Business Advisory Panel met seven times from April to June, 1998.  Many of the panel’s recommendations have been incorporated into the proposed rule.

In February 1999, EPA posted an informal draft of the GWR preamble on the Internet.  Approximately 300 copies were also mailed to participants of public meetings or to those who requested a copy.  EPA  received valuable comments and stakeholder input from over 80 individuals representing States, trade associations, environmental interest groups, as well as individual stakeholders.

Public comment on the Proposed Rule

EPA took public comment on the proposed Ground Water Rule for 60 days.  The comment period closed August 4, 2000. EPA received over 250 comments. For more information, the general public can call the Safe Drinking Water Hotline at 800-426-4791.  A fact sheet, the proposal, and additional information are also available at http://www.epa.gov/safewater/gwr/gwrfs.html.

What Requirements are Proposed in the GWR?

• System sanitary surveys conducted by the State and identification of significant deficiencies;
• Hydrogeologic sensitivity assessments for undisinfected systems;
• Source water microbial monitoring by systems that do not disinfect and draw from hydrogeologically sensitive aquifers or have detected fecal indicators within the system’s distribution system;
• Corrective action by any system with significant deficiencies or positive microbial samples indicating fecal contamination; and 
• Compliance monitoring for systems which disinfect to ensure that they reliably achieve 4-log (99.99 percent) inactivation or removal of viruses.

Sanitary Surveys

Applies to: 

All ground water systems

Every 3 years for community water systems; 5 years for non-community water systems, consistent with the 1998 Interim Enhanced Surface Water Treatment Rule (Community water systems serve the same populations year round, e.g., houses and apartment buildings. Non-community water systems do not serve the same people year round, e.g., schools, factories, office buildings, hospitals, gas station and campgrounds.)

• State must perform each system’s sanitary survey and address the 8 elements from the joint EPA and Association of State Drinking Water Administrators guidance. 
• State must have authority to enforce corrective action requirements.
• State must provide a list of significant deficiencies (e.g., those that require corrective action) to the system within 30 days of identification of the deficiencies.

Applies to: 

All ground water systems which do not provide 4-log (99.99%) virus inactivation/removal

One-time assessment of sensitivity (within 6 years of the final rule’s date of publication for community water systems and 8 years for non-community water systems).  Sensitive systems must monitor monthly (see below).

State must conduct a one-time assessment of all systems that do not provide 4-log virus inactivation/removal to identify those systems located in sensitive aquifers.

EPA considers karst, gravel, or fractured bedrock aquifers to be “sensitive” to microbial contamination.  States may waive source water monitoring for sensitive systems if there is a hydrogeologic barrier to fecal contamination.

Applies to: 

Ground water systems that are sensitive or have contamination in their distribution system (“triggered monitoring”) and do not treat to 4-log removal or inactivation of viruses

Monthly for sensitive systems; once for triggered monitoring 

• Routine Monitoring. For systems determined by the State to be hydrogeologically sensitive, the system must conduct monthly source water monitoring for fecal indicators. Sampling frequency may be reduced after twelve negative samples.
• Triggered Monitoring.  If a total coliform-positive sample is found in the distribution system, then the system must collect one source water sample and monitor for a fecal indicator.

Applies to: 

Ground water systems that have a significant deficiency or have detected a fecal indicator in their source water

Correct within 90 days or longer with a State-approved schedule

• Significant Deficiency or Source Water Contamination.  If a ground water system is notified of significant deficiencies by the State, or notified of a source water sample positive, within 90 days it must correct the contamination problem by eliminating the contamination source, correct the significant deficiencies, provide an alternative source water or install a treatment process which reliably achieves 4-log removal or inactivation of viruses.  A system may take longer than 90 days for corrective action with a State-approved plan.  Systems must notify the State of completion of the corrective action or the State must confirm correction within 30 days after the 90 day period or scheduled correction date. 
• Treatment. Systems providing treatment must monitor treatment to ensure at least 4-log virus inactivation and/or removal. 

Applies to: 

Applies to all ground water systems that notify States they disinfect in order to avoid source water monitoring, and to systems which disinfect as a corrective action.

Systems serving less than 3,300 must monitor disinfection treatment once daily, while systems serving 3,300 or more people must monitor their disinfection treatment continuously.

• If monitoring shows the disinfection concentration to be below the required level, the system must restore the disinfection concentration within 4 hours or notify the State.

For general information please contact the Safe Drinking Water Hotline at (800) 426-4791.  The Safe Drinking Water Hotline is open Monday through Friday, excluding Federal holidays, from 9:00 am to 5:30 PM Eastern Time. 

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