In an effort to spur the cleanup of more than 300,000 miles of rivers, lakes and estuaries, the EPA has proposed new rules for how states write — and implement — cleanup plans for waterbodies still polluted nearly three decades after passage of the Clean Water Act.

The new rules govern the development of cleanup plans known as “Total Maximum Daily Loads,” or TMDLs, and seek to force states to better rein in sources of pollution that previously went largely uncontrolled, such as runoff from farms and developments.

The proposed rules were announced by President Clinton in his weekly radio address Aug. 14. He said under the new plan, the EPA would work with the states to “to assess the state of all our waterways, to identify the most polluted waters and to develop strong, enforceable plans to restore them to health.”

The rules encourage states to develop new permit programs, if necessary, to guarantee that their cleanup programs will be successful.

The TMDL program is aimed at making pollution control efforts focus on the health of an entire body of water by looking at all sources of pollution rather than individual dischargers. While regulating end-of-the-pipe pollution has helped to clean waterways, about 300,000 miles of rivers and 5 million acres of lakes are still polluted, largely because of runoff from farms, abandoned mines, development and other land activities.

TMDLs have actually been required under the Clean Water Act for 27 years, but were rarely completed. According to the law, states were supposed to monitor their waterways and submit to the EPA a 303(d) list — sometimes called a “dirty waters list” — every two years.

The list was to identify all waterbody “segments” where water standards were not being met, identify the pollutant — or pollutants — causing the problem, and then develop a TMDL. Simply put, a TMDL is a calculation of the maximum amount of a given pollutant a waterbody can absorb and still meet the water quality standard.

Once that calculation was made, states were to reduce pollution from sources contributing to the problem until the standard was met with an adequate “margin of safety.” The plans were to be submitted to the EPA for approval.

Almost all of those requirements went largely ignored until a spate of more than 40 suits brought by environmental groups in recent years began forcing the EPA to require stepped-up monitoring and TMDL development, with set timetables. So far, more than 20,000 segments needing TMDLs have been identified nationwide, including hundreds in the Bay states.

Unfortunately, the act was vague about critical details concerning TMDLs. How long it should take to develop a TMDL — even whether the plans had to be implemented — was never spelled out.

Now, the EPA has produced hundreds of pages of new rules and guidelines that not only clarify details, but also attempt to make the plans a “fundamental tool” for attaining water quality goals. The agency is strongly encouraging that TMDLs be “bundled together” to clean up entire watersheds.

The new rules seek to guarantee that TMDLs will be carried out, regardless of where the pollution comes from. In the past, it had been unclear how a TMDL would be implemented if most of the problem resulted from unregulated runoff sources.

Under the new rules, states must develop an implementation plan for a TMDL which includes “reasonable assurance” that the pollution controls will be achieved from “point” sources, such as industry and wastewater treatment plans, as well as from “nonpoint” sources, mainly runoff. The EPA defines reasonable assurance as a “high degree of confidence” that the wasteload allocations made to pollution sources will be carried out.

For point sources, that means permits will be revised to meet TMDL requirements. For nonpoint sources, voluntary actions or local ordinances and zoning requirements may be acceptable, but states would have to show that adequate funding or other mechanisms are in place to achieve the results on a predictable timetable.

If monitoring shows that the goal is not being achieved, the proposed rule says, states “may need to establish a regulatory approach.” The new rules allow states to decide that some major nonpoint sources could be required to have a discharge permit, just like an industry, making them subject to regulation and specific pollution limits.

If states don’t take enough action to control runoff pollution, the rules give the EPA authority to designate certain operations, such as animal feedlots, aquaculture facilities and certain forestry activities, as point sources and require discharge permits.

Under the new rules, states will have up to 15 years to complete TMDLs. But the rules do not set a timetable for implementation once plans are drawn up, although a timetable is supposed to be part of each TMDL.

Until TMDLs are developed, the new rules seek to prevent the further degradation of a waterbody by requiring that any large new — or significantly expanded — discharge source offset its pollution by achieving reductions from an existing source on the same waterbody.

Offsets may be achieved from either point sources or from nonpoint sources. Generally, they are to be 1.5 times greater than the amount of the new discharge, according to the proposal.

The new rules also create a new priority system for completing TMDLs. Plans are to be written first for “high priority” waterbodies, which are used for public drinking water supplies or contain a threatened or endangered species. The completion of TMDLs in high priority watersheds will be sought in 5 years.

The rules also more clearly spell out the procedures for public participation. The public is to be notified and have the opportunity to comment on lists, priority rankings, schedules and TMDLs before they are submitted to the EPA, which is ultimately responsible for approving the cleanup plans.

Also, the public may petition the EPA to establish TMDLs where a state has failed to do so consistent with its schedule.

The public has 60 days to comment on the rules. Details about the proposals, and information about how to comment, is available on the Internet at:

www.epa.gov/owow/tmdl/