The Minnesota Pollution Control Agency (MPCA) has issued its new general stormwater permit for industrial activities, effective today. NPDES/SDS Multi-Sector General Permit for Industrial Stormwater Activity No. MNR050000 replaces the previous General Storm Water Permit for Industrial Activity No. MNG611000, which expired on October 31, 2002. Businesses that are required to obtain coverage under the new permit must file applications with the MPCA within 60, 120 or 180 days from today, depending on the type of business.

Who Must Apply?

Facilities that fall within any one of 11 categories of industrial activities must apply for coverage under the new permit. These 11 categories encompass 29 specific Standard Industrial Classification (SIC) codes. Some examples of industrial activities covered by the permit are manufacturing and processing of food, wood, rubber, plastics, chemicals, textiles and other products; vehicle maintenance; scrap recycling; nonferrous metals smelting and refining; leather tanning and finishing; petroleum refining; and mineral mining. A complete list of the applicable SIC codes can be found here.

The new permit covers the same facilities as the expired permit. Thus, if your facility obtained coverage under the expired permit , you will need to apply for coverage under the new permit. If your facility did not obtain coverage under the expired permit, you should not assume that the new permit does not apply to you. The MPCA estimates that there are 4,000 facilities in Minnesota that were required to obtain coverage under the expired permit, but failed to do so.

A facility does not need to obtain coverage under the permit if the facility certifies its eligibility for the No Exposure exclusion. In order to qualify for the No Exposure exclusion, all significant industrial materials and activities must be sheltered from rain, snow and run-off.

What Has Changed?
The new permit retains many of the requirements of the expired permit, such as development and implementation of a site-specific Stormwater Pollution Prevention Plan (SWPPP), periodic self-inspections and filing annual reports with the MPCA. But it also contains some new requirements, including:

• Sector-Specific Requirements: The new permit imposes certain obligations and limitations on stormwater discharges that vary with the type of industrial activity. Among the things that vary by sector are the pollutants to be monitored, the stormwater management practices to be employed and the employee training to be conducted. For example, vehicle maintenance facilities are required to train employees in proper management of used oil and spent solvents.
• Monitoring: Permitted facilities will now be required to periodically monitor stormwater for specific pollutants and to bring concentrations within stated standards for these pollutants in the form of either "Benchmark Values" or "Effluent Limits." The majority of permitted facilities are required to meet stated Benchmark Values. Exceeding these values does not constitute a permit violation, but facilities with exceedances must revise their management practices and engage in further monitoring until the concentrations are below the Benchmark Values. Facilities that are engaged in activities that the MPCA views as higher risk for stormwater pollution, such as fertilizer manufacturing, sand mining and cement manufacturing, are required to comply with more stringent Effluent Limits. A facility that exceeds Effluent Limits is in violation of the permit.
• Non-Degradation Provisions: The new permit also contains provisions that are designed to protect clean waters and prevent further degradation of the state's Impaired Waters. Consequently, discharges to certain water bodies, including Outstanding Resource Value Waters as defined in Minnesota Rules 7050.0180, Trout Waters as defined in Minnesota Rules 6264.0050, wetlands as defined in Minnesota Rules 7050.0186 and Impaired Waters may be prohibited or restricted. A list of Minnesota's Impaired Waters can be viewed here.

The new permit applies only to stormwater discharges associated with industrial activities. It is important to remember that stormwater discharges from construction sites and municipal stormwater sewer systems require different permits.