Credit: SCS Engineers
This construction site includes outfall protection with rip-rap. Slope stabilization techniques had to be used to construct a proper outfall. Outfalls should be constructed so that they do not increase erosion.
As stormwater flows through industrial areas, construction sites, and urban environments, various pollutants are transported and deposited into waterways, affecting the beneficial uses of the receiving waters. As part of most programs that require stormwater permits, a stormwater pollution prevention plan (SWPPP) must be developed and implemented to reduce or eliminate pollutants from industrial activities and construction sites.
SWPPPs have two major objectives. First, a plan helps identify sources of potential pollution that may affect the quality of industrial or construction stormwater discharges and authorized non-stormwater discharges. Second, a plan helps describe and ensure the implementation of best management practices (BMPs) to reduce or prevent pollutants in stormwater discharges. These objectives assist public works department employees in managing stormwater systems and implementing stormwater programs. By implementing a proper program, a municipality can reduce or eliminate possible pollutants and promote good water quality.
SWPPPs also are used to ensure compliance with regional permit requirements. They become a dynamic document to help track the success of a site's stormwater program. For example, a municipality that operates a vehicle maintenance yard, maintains a green waste collection and storage facility, or conducts street repairs must comply with an industrial permit for those sites. However, if a city conducts construction activities that disturb an acre or more of soil, the site requires a construction permit.
With some variation, the process of planning and organization, assessment, identification of BMPs, implementation, and evaluation can be applied to both types of permits. Some of this information also holds true for municipal permits.STARTING THE ASSESSMENT
Forming a pollution prevention team is one of the first steps in the process. A team's size may vary depending on the size of the facilities. Department leaders or others who are most familiar with the facilities and operations should be included. An individual or a small team should be designated to develop, implement, maintain, and revise the plan, while the others provide input.
Develop a site map that illustrates the location of site activities, noting points of discharge or outfalls, runoff patterns, structural control measures, locations of significant material that may enter runoff, and locations of industrial activities such as loading areas, fueling areas, and waste disposal areas. A site map also should include nearby surface water bodies.
The types of materials stored, handled, or processed at the facilities must be inventoried. These materials may include gasoline, solvents, raw materials, and waste. Record any spills or leaks of hazardous materials that have occurred in the past three years in excess of reportable quantities as specified by the Comprehensive Environmental Response, Compensation, and Liability Act. Describe any activities that may contribute to stormwater pollution and pollutants present in these areas. An assessment should include the locations of all outside industrial and construction activities.
Following the assessment phase, BMPs are selected to reduce or eliminate pollutants from site activities. BMPs may take the form of engineered, structural approaches and non-structural approaches such as standard operating procedures. BMPs are selected based on the most effective practice for the activity to be controlled. A number of sources are available on the Web to assist in choosing an appropriate BMP. Furthermore, some states have developed BMP manuals that list various types of BMPs and their specific applications.
At the start of the implementation process, it is important to have the appropriate controls for a specific activity. Develop a schedule for implementating these controls and delegate the responsibilities to specific individuals for certain aspects of the plan and monitoring.