The US Environmental Protection Agency (EPA) announced on 17 June 2010 that it is proposing to revise the 1989 Total Coliform Rule to incorporate improvements recommended by a federal advisory committee.
The revised rule requires those responsible for drinking water systems to take action when monitoring results indicate that contamination or a pathway to contamination may be present.
US water utilities are required to monitor regularly for microbial contamination in the distribution system. Although microbes detected in monitoring are not necessarily pathogens themselves, the detection can indicate that there is a pathway that would allow pathogens to enter the system, such as a water main break or an opening in a storage tank.
Under the proposed rule, when monitoring results are positive, systems must find and fix any pathways leading to microbial risk. The proposal also provides incentives for better system operation by improving the criteria for public water systems to qualify for and stay on reduced monitoring, which provides an opportunity to reduce system burden.
In addition, the proposed rule updates conditions that will trigger public notices to better represent the relative health threat identified. It also makes the wording required in these public notices more clear.
EPA is seeking public comment on this proposed rule for 60 days following publication in the Federal Register.
More information about the proposed rule can be found online.