Under the Safe Drinking Water Act (SDWA), EPA is required to establish disinfection requirements for groundwater systems. A system in this case includes the source, well, treatment hardware and distribution lines. The existing Total Coliform Rule (TCR) mandates monitoring for fecal contamination in public water supplies, but does not explicitly require correction of violations or other identified problems. Additionally, it only acts "after the fact," since by the time TCR monitoring results have revealed contamination, people have already consumed the contaminated water. Congress asked EPA to ensure additional protection to the public to prevent such situations. Currently, many states have some groundwater system protection and/or disinfection regulations already in place, although the specific requirements vary substantially. The GWDR will provide the national guidance and requirements to correct problems and provide adequate protection.

Why the Public Health Concern?
There are legitimate concerns for public health from microbial contamination of groundwater systems. Microorganisms and other evidence of fecal contamination have been detected in a large number of wells tested, even those wells that had been previously judged not vulnerable to such contamination. The scientific community believes that microbial contamination of groundwater is real and widespread. Public health impacts from this contamination while not well quantified, appear to be large. Disease outbreaks have occurred in many groundwater systems. Risk estimates suggest several million illnesses each year. Additional research is underway to better characterize the nature and magnitude of the public health problem.

Current Thinking on Regulatory Elements
The working public health goal for the GWDR is to protect consumers from fecal contamination in their drinking water. To achieve this goal, the final regulation should ensure adequate protection of sources, wells and distribution systems from fecal contamination and provide treatment if contamination occurs. In addition, it must be feasible to implement and enforce. Options so far actively being considered center around a general requirement for a periodic sanitary survey to include wells and treatment, distribution, operations and management, and monitoring and assessment. Correction of fecal contamination or system defects would be required, which could include installation of treatment. Maintenance of a distribution system disinfectant residual (for systems with distribution) has wide support. A groundwater vulnerability assessment may be required. Highly vulnerable sources would have additional source water monitoring requirements. Monitoring requirements may focus on E.coli and coliphage as indicators of fecal contamination. Operator training or certification will likely be required.

How Might Small Community Systems be Affected?
Groundwater-based public water supply systems are substantially different from surface water systems. Also, groundwater systems have very different circumstances with respect to each other and to the likely elements of this rule. Compared to larger groundwater systems, the small community systems (serving fewer than 1000 people) have fewer resources and less routine oversight. Small non-community systems (schools, restaurants, etc) typically have even more limited resources and infrastructure. Most have no distribution system. The majority do not disinfect or treat their water at all. Operators are generally not certified. These small systems have the majority of microbial violations, mostly from source or wellhead contamination. They are not well represented in the drinking water community. Because of their resources and limited current involvement with drinking water regulations, the GWDR would likely have the most noticeable impact on these systems. New SDWA amendments direct EPA to specifically consider the feasibility of regulatory requirements for small systems. 

Current Workgroup Activities
There has been wide and open participation in the regulatory discussions, including representatives from states, utilities, EPA, other agencies and interest groups. Over the last two years, broad issues of public health problems and goals, existing state protection approaches, vulnerability assessment methods and general treatment possibilities have been considered. As the workgroup discussions have developed, several topic areas have been identified for detailed study. Information-gathering groups are now examining the public health and microbiological monitoring issues, existing state and federal regulations and approaches, criteria for sanitary surveys, possible requirements for operations and maintenance, and appropriate treatment technologies. It is expected that these groups will bring forward their recommendations during 1996. EPA is anticipating a proposed GWDR by mid-1998. 

How Can You Get Involved?
The GWDR discussions are open to all. Interested parties are encouraged to participate, especially members from small communities. If you are interested or want more information on this rule, contact Bruce Macler, GWDR Regulation Manager, at 415 744-1884 or macler.bruce@epamail.epa.gov.