EPA's Residual Designation Authority

Lynn J. Preston and John E. Peltonen

What is RDA?

Nestled in midst of the Clean Water Act’s (CWA’s) complex permitting requirements and related regulations is a little known and, until recently, little used “catch-all” provision that authorizes the Environmental Protection Agency (EPA) to issue stormwater discharge permits for existing unpermitted discharges relating to commercial, industrial and institutional sites. This authority, also known as Residual Designation Authority (RDA), gives EPA the ability to regulate stormwater discharges via the CWA’s primary permitting program, the long established National Pollutant Discharge Elimination System (NPDES). For sites where EPA determines that storm water controls are needed for the discharge as part of meeting the required total maximum daily loads (TMDLs), that the discharge or category of stormwater discharges within a geographic area contributes to a violation of a water quality standard, or that the stormwater discharge is a significant contributor of pollutants to waters of the United States, RDA allows EPA to designate these stormwater sources for regulation. 40 C.F.R. § 122.26(a)(9)(i)(C) and (D). Essentially, what RDA does - and why it has recently become so popular to environmental advocacy groups - is to provide an avenue for the federal government to expand the scope of the CWA’s permitting coverage beyond the traditional industrial and municipal general permit programs to include the regulation of sites on a case-by-case or category-by-category basis by issuing NPDES permits for discharges of stormwater which result in localized adverse impacts to water quality. For example, individual sites now subject to regulation through RDA include industrial, commercial and residential sites often with impervious areas of one or two acres.

Why Now?

Historically, and until very recently, NPDES permits were issued for discharges associated with new construction projects under the Construction General Permit (CGP) program, for industrial sites falling within specific categories under the Multi-Sector General Permit (MSGP) program and for municipal stormwater systems under the Municipal Separate Storm Sewer System (MS4) Permit program. For years, these NPDES permits were the main instruments in EPA’s regulatory tool box for controlling and monitoring stormwater runoff.  However, EPA, and particularly Region I, have recently been “sharpening” RDA to expand its tool box to include the imposition of stormwater discharge requirements through the use of NPDES permits on additional sources not currently covered by the above listed programs. This expansion will allow EPA to begin to regulate water quality issues relating to urbanization, often called non-point source discharges, the implications of which could greatly affect local land use controls.

How and Where is RDA Being Applied?

The following are examples illustrating how environmental advocacy groups and EPA have recently used – and are in the process of using – RDA to impose stormwater discharge requirements on currently unregulated discharges.

In 2008 the Conservation Law Foundation (CLF) effectively petitioned EPA to use RDA to designate stormwater discharges from certain existing sites in Maine’s Long Creek watershed. Under the federal regulations, 40 C.F.R. § 122.26(f)(2), any person is allowed to petition the EPA to require a NPDES permit for a discharge of stormwater where that discharge either contributes to a violation of water quality standards or is a significant contributor of pollutants to the waters of the United States. The State of Maine is a NPDES delegated state and, thus, the Maine Department of Environmental Protection (MEDEP) is the permitting authority in the State responsible for administering the NPDES permit program, including permits for designations made under RDA. Thus, in October 2009, as a result of EPA’s designation of the Long Creek watershed, MEDEP issued a general permit for the designated discharges in the watershed. These designated discharges included, among others, municipalities, transportation agencies, and commercial and retail properties with one acre or more of impervious surface. Under the general permit, property owners had the option of either participating in implementation of the collaboratively developed Watershed Management Plan (administered through a Watershed Management District) or obtaining an individual MEDEP permit and treating their individual discharges. The permit is currently in its fourth year of implementation and renewal is scheduled by 2014.

Also in 2008, EPA Region I- took its own action under RDA to require all private commercial, industrial, institutional, and high-density residential properties of one or more impervious acre(s) (ultimately changed in the draft permit to two or more acres) discharging stormwater into the upper Charles River watershed in Massachusetts to operate under a NPDES permit. Not surprisingly, CLF and the Charles River Watershed Association in a letter dated February 6, 2009 formally petitioned the EPA for designation of the same. EPA remains the permitting authority in Massachusetts (and in New Hampshire) and, thus, issued a draft general permit in May of 2010 for residually designated discharges in the municipalities of Milford, Bellingham and Franklin, Massachusetts. The draft permit applies to any owner and/or operator of a designated discharge (designated discharge is defined in the draft permit as a discharge from two or more acres of impervious surfaces located in the Charles River watershed in whole or in part in the municipalities of Milford, Bellingham and Franklin…) from which there is a stormwater discharge either directly to the Charles River or its tributaries or indirectly to the Charles River or its tributaries through an MS4. The draft residual designation permit requires the implementation of a series of stormwater controls, including Best Management Practices (BMPs), designed to reduce phosphorus loadings, the development and implementation of a comprehensive Storm Water Management Plan and a Phosphorus Reduction Plan. Sites subject to the general permit will be required to reduce total phosphorus load in their discharge by 65% (the current draft MS4 for the Massachusetts North Coastal Watersheds requires total phosphorus reductions of 57.0%, 51.8% and 52.1% for the towns of Milford, Bellingham and Franklin, respectively). The draft permit provides alternatives for achieving the required phosphorus reductions such as using structural or non-structural BMPs or by joining a Certified Municipal Phosphorus Program (CMPP) administered by the municipality. While the draft RDA permit sets out compliance options for designated dischargers, such as described above, it does not specify how municipalities might structure a stormwater management program or fund existing and future permit requirements. The Charles River Watershed permit is still in draft form, likely due to the number of comments and high cost associated with meeting permit requirements.

Most recently, on July 10, 2013, CLF and other environmental organizations, including the Natural Resources
Defense Council and American Rivers, petitioned EPA Regions 1, 3, and 9 to use RDA to impose permit requirements on non-de minimis, currently non-NPDES permitted, stormwater discharges from impervious surfaces contributing to violations of water quality at existing commercial, industrial, and institutional sites located throughout New England, the Mid-Atlantic, and California and the Southwest. Per the federal regulations, EPA had 90 days (until October 8, 2013) to either grant or deny the petition. As of the date of this article, EPA has not responded to the pending petition. When EPA does respond, and if granted, the EPA’s use of RDA as a tool to regulate designated discharges would be expanded to a regional level and implications to the currently unpermitted sources and municipalities are, thus, difficult to predict. Also, if granted, due to the broad scope of CLF’s (and other parties’) petition, two very important items would need to be clearly defined in EPA’s decision, what constitutes a “non-de minimis” discharge and what it means to be a “commercial,” “industrial” or “institutional” site.

RDA in Sum

While the EPA and environmental advocacy groups through the RDA process seem to have found a way to expand the scope of the CWA’s stormwater permitting coverage, they have clearly not provided resources for designated dischargers and/or municipalities to fund ongoing improvements and other items and activities needed to ensure compliance requirements are met. Thus, designated dischargers are left to determine how they will ultimately comply and fund the new federal mandates.

Lynn J. Preston is an Attorney with Sheehan Phinney Bass + Green PA. She may be contacted at 603-223-2020. John E. Peltonen is a Shareholder with Sheehan Phinney Bass + Green PA. He may be contacted at 603-668-0300.