United States Office of Water EPA 833-F-99-002 Environmental Protection (4203) April 1999 Agency Fact Sheet 2.0 SEPA Storm Water Phase II Proposed Rule Fact Sheet Series Overview 1.0 - Storm Water Phase II Proposed Rule Overview Small MS4 Program 2.0 - Small MS4 Storm Water Program Overview 2.1 - Who's Covered? Designation and Waivers of Regulated Small MS4s 2.2 - Urbanized Areas: Definition and Description Minimum Control Measures 2.3 - Public Education and Outreach Minimum Control Measure 2.4 - Public Participation/ Involvement Minimum Control Measure 2.5 - Illicit Discharge Detection and Elimination Minimum Control Measure 2.6 - Construction Site Runoff Control Minimum Control Measure 2.7 - Post-Construction Runoff Control Minimum Control Measure 2.8 - Pollution Prevention/Good Housekeeping Minimum Control Measure 2.9 - Permitting and Reporting: The Process and Requirements 2.10 - Federal and State-Owned MS4s: Program Implementation Construction Program 3.0 - Construction Program Overview Industrial "No Exposure" 4.0 - Conditional No Exposure Exemption for Industrial Activity Storm Water Phase II Proposed Rule Small MS4 Storm Water Program Overview This fact sheet is based on the Storm Water Phase II Proposed Rule. Therefore, the information provided herein is subject to change upon publication of the final Phase II rule in November 1999. A revised series of fact sheets will be provided at that time. A comprehensive list of the current fact sheets is in the text box at left. Polluted storm water runoff is often transported to municipal separate storm sewer systems (MS4s) and ultimately discharged into local rivers and streams without treatment. EPA's Storm Water Phase II Proposed Rule would establish an MS4 storm water management program that is intended to improve the Nation's waterways by reducing the quantity of pollutants that storm water picks up and carries into storm sewer systems during storm events. Common pollutants include oil and grease from roadways, pesticides from lawns, sediment from construction sites, and carelessly discarded trash, such as cigarette butts, paper wrappers, and plastic bottles. When deposited into nearby waterways through MS4 discharges, these pollutants can impair the waterways, thereby discouraging recreational use of the resource, contaminating drinking water supplies, and interfering with the habitat for fish, other aquatic organisms, and wildlife. In 1990, EPA promulgated rules establishing Phase I of the National Pollutant Discharge Elimination System (NPDES) storm water program. The Phase I program for MS4s requires owners or operators of "medium" and "large" MS4s, that is, those that typically serve populations of 100,000 people or more, to implement a storm water management program as a means to control polluted discharges from these MS4s. The Storm Water Phase II Proposed Rule would extend coverage of the NPDES storm water program to certain "small" MS4s but takes a slightly different approach to how the storm water management program would be developed and implemented. What Is A Phase II Small MS4? A small MS4 is any MS4 not already covered by the Phase I program as a medium or large MS4. The Phase II Proposed Rule would automatically cover on a nationwide basis all small MS4s located in "urbanized areas" (UAs) as defined by the Bureau of the Census, and on a case-by-case basis those small MS4s located outside of UAs that are designated by the NPDES permitting authority. For more information on Phase II small MS4 coverage, see Fact Sheets 2.1 and 2.2. What Would Be the Phase II Small MS4 Program Requirements? O wners or operators of regulated small MS4s would be required to design their programs to: ~ Reduce the discharge of pollutants to the "maximum extent practicable" (MEP); and ~ Protect water quality. The successful implementation of approved best management practices (BMPs) is considered compliance with the technical standard of MEP. The Phase II Proposed Rule would consider narrative effluent limitations that require the implementation of BMPs and the achievement of measurable goals as the most appropriate form of effluent limitations to achieve the protection of water quality, rather than requiring storm water discharges to meet numeric effluent limitations. The Phase II Proposed Rule outlines a small MS4 storm water management program comprising six required program elements that, when implemented in concert, are expected to result in significant ------- Fact Sheet 2.0 - An Overview of the Small MS4 Storm Water Program Page 2 reductions of pollutants discharged into receiving waterbodies. The proposed six program elements, termed "minimum control measures," are outlined below. For more information on each of these required control measures, see Fact Sheets 2.3 through 2.8. o Public Education and Outreach Distributing educational materials and performing outreach to inform citizens about the impacts polluted storm water runoff discharges can have on water quality. © Public Participation I Involvement Providing opportunities for citizens to participate in program development and implementation, including effectively publicizing public hearings and/or encouraging citizen representatives on a storm water management panel. © Illicit Discharge Detection and Elimination Developing and implementing a plan to detect and eliminate illicit discharges to the storm sewer system (includes developing a system map and informing the community about hazards associated with illegal discharges and improper disposal of waste). © Construction Site Runoff Control Developing, implementing, and enforcing an erosion and sediment control program for construction activities that disturb 1 or more acres of land (controls could include silt fences and temporary storm water detention ponds). © Post-Construction Runoff Control Developing, implementing, and enforcing a program to address discharges of post-construction storm water runoff from new development and redevelopment areas. Applicable controls could include preventative actions such as protecting sensitive areas (e.g., wetlands) or the use of structural BMPs such as grassed swales or porous pavement. identify the most appropriate BMPs for their programs, the proposed rule would require the NPDES permitting authority to issue a list, or "menu," of BMPs to serve as guidance. For more information on application requirements, see Fact Sheet 2.9. Would There Be Implementation Options? Yes. The proposed rule would allow for a number of implementation options to be chosen by the regulated small MS4 owners or operators responsible for developing Phase II municipal storm water programs. Such options would include sharing responsibility for program development with a nearby regulated small MS4, taking advantage of existing local or State programs, or participating in the implementation of an existing Phase I MS4's storm water program as a co-permittee. These options are intended to promote a regional approach to storm water management coordinated on a watershed basis. What Kind of Program Evaluation/Assessment Would Be Required? Permittees would need to evaluate the effectiveness of their chosen BMPs in terms of reducing the discharge of pollutants from their systems to the "maximum extent practicable" and in terms of protecting water quality. Permittees also would be required to assess their progress in achieving the program's measurable goals. The evaluation would not be based on monitoring data, since permittees are expected to meet only narrative, rather than numeric, effluent limitations. Monitoring is not required under the proposal but the NPDES permitting authority would have the discretion to require monitoring if deemed necessary. If there is an indication of a need for improved controls, permittees could revise their mix of BMPs to provide for a more effective program. For more information on program evaluation/assessment requirements, see Fact Sheet 2.9. For Additional Information Contact U. S. EPA Office of Wastewater Management • Phone : 202 260-5816 E-mail: SW2@epa.gov Internet: www.epa.gov/owm/sw2.htm Reference Documents Storm Water Phase II Proposed Rule Fact Sheet Series. Contact the U.S. EPA Water Resource Center at 202 260-7786 or at waterpubs@epa.gov Internet: www.epa.gov/owm/sw2.htm Storm Water Phase II Proposed Rule, published on Jan. 9, 1998 in the Federal Register (63 FR 1536). Internet: www.epa.gov/owm/sw2.htm © Pollution Prevention/Good Housekeeping Developing and implementing a program with the goal of preventing or reducing pollutant runoff from municipal operations. The program must include municipal staff training on pollution prevention measures and techniques (e.g., regular street sweeping, reduction in the use of pesticides or street salt, or frequent catch-basin cleaning). What Information Would Be Included in the NPDES Permit Application? Rather than individual permits, which were required for the Phase I MS4s, the proposed Phase II program for MS4s is designed to accommodate a general permit approach using a Notice of Intent (NOI) as the permit application. The owner/ operator of a regulated small MS4 would need to include in its permit application, or NOI, its chosen BMPs and measurable goals for each minimum control measure. To help permittees ------- |