Guidance Coming to Assist States, Regions In Setting Discharge Limits to Cut Nutrients

The Environmental Protection Agency confirmed March 22 that it is developing guidance to help state and regional permitting authorities develop water quality-based pollutant discharge limits and permit conditions to reduce nutrients from municipal and industrial wastewater treatment facilities.

The guidance, expected to be final by May 2012, will build upon a recommended framework for managing nutrients, which EPA recently sent to regional administrators and state water officials, the agency told BNA in an e-mail (42 ER 566, 3/18/11).

Excess levels of nitrogen and phosphorus in surface water contribute to oxygen-starved dead zones and can harm aquatic life.

The framework recommended that states prioritize watersheds for nutrient reductions and that targeted priority “sub-watersheds” be identified within major watersheds for nutrient and phosphorus reductions. It recommended establishing numeric goals for loading reductions for each priority sub-watershed.

One aspect of the framework is to “ensure effectiveness of point source permits in these targeted/priority sub-watersheds for municipal and industrial wastewater treatment facilities that contribute to significant nutrient nitrogen and phosphorus loadings.”

“The guidance being developed by EPA will help state and regional permitting authorities with this element of the framework,” the agency told BNA in its e-mail.

The framework recommended that states establish a work plan and phased schedule for developing nutrient criteria for various classes of waters

Final Document Planned by May 2012.

Options to be included in the planned National Pollutant Discharge Elimination System permit writers guide for implementing nutrient criteria are expected to be selected in June, with the final document scheduled for release in April or May 2012, according to EPA.

In a fact sheet on the planned guidance released to state water officials during a meeting of the Association of State and Interstate Water Pollution Control Administrators earlier this month, EPA said clarification is needed for developing water quality-based effluent limitations for nitrogen and phosphorus.

There are few national technology-based standards for nutrients for industrial dischargers and no national technology standards for nutrients for publicly owned treatment works, the agency said.

“Consequently, effluent limitations for nutrients in permits rely on case-by-case technology-based limitations, state treatment requirements, or implementation of water quality standards through water quality-based effluent limitations.”

Numeric Limitations Key Issue.

A key policy issue the agency is considering addressing in the guidance is how to translate state standards into numeric water quality-based effluent limitations. This could involve looking at narrative standards, including those that “are free from nuisance conditions” or in amounts that cause poor water quality conditions, EPA said.

Another key issue under consideration is how to determine if a facility has “reasonable potential” for exceeding nutrient requirements--in the absence of numeric limits or modeling data, and accounting for downstream uses and standards.

In addition, the guidance is expected to address how to develop water quality-based effluent limitations for nutrients. Factors could include concentrations versus mass limits, an appropriate average period, seasonal limits, mixing zones, and critical flow conditions.

Among other questions that may be addressed by the guidance are:

• What alternatives exist when permit limits are so low that they cannot be reliably achieved by current technology?

• What is the importance of data collection and modeling when dealing with nutrient pollution? and

• How can water quality trading and watershed-based permitting be a useful tool in addressing nutrient pollution?

'Unique Issues' Presented.

The process for determining the need for and, where necessary, calculating water quality effluent limitations for nutrients presents “unique issues” that are not fully addressed by existing national guidance contained in EPA's National Pollutant Discharge Elimination System Permit Writers Manual and the 1991 Technical Support Document for Water Quality-Based Toxics Control, EPA said in the fact sheet.

“These issues include a lack of numeric criteria for nutrients in state water quality standards and permitting procedures that focus on fast-acting, toxic pollutants rather than pollutants such as nutrients, which typically have longer-term and, often, far-afield effects,” the agency said.

Some states have developed treatment standards that generally apply a uniform requirement to point sources within a certain category, such as publicly owned treatment works, or within a particular watershed, according to EPA. However, the agency said, few permitting authorities have developed nutrient standard procedures for developing water quality-based effluent limitations for nutrients that address “the unique issues presented by these pollutants.”

Nutrient pollution, which is linked to stormwater runoff from agricultural and municipal sources, is a major problem confronting federal and state regulators. It also has stirred concern from environmental groups.

Guidance Called 'Stopgap Measure.'

Jon Devine, an attorney with the Natural Resources Defense Council, told BNA March 22 that while NRDC supports EPA's efforts to improve water quality and believes a guidance will be helpful to water permittees, he considers a nutrient guidance as just a “stopgap measure.”

“EPA needs to be more aggressive with the states,” he said, adding that states need to adopt numeric nutrient standards.

The agency has mandated the adoption of numeric nutrient standards by only one state, Florida, because it was under court order to do so. The result has been a flurry of lawsuits challenging EPA's authority (42 ER 81, 1/14/11).

State and municipal water officials have opposed federal numeric nutrient mandates. Alexandra Dunn, counsel and executive director of the Association of State and Interstate Water Pollution Control Administrators, told BNA that states have not yet been consulted but that state officials hope to work with EPA in developing the guidance.

By Linda Roeder