Industrial storm water permit overview
Tier 1 and Tier 2 industrial facilities
Natural Resources Chapter 216, Wis. Adm. Code, (NR 216) lists certain types of industries in the state that need to obtain storm water discharge permits from the Department of Natural Resources. Permits are issued under a tiered system that groups industries by type and by how likely they are to contaminate storm water. NR 216 lists industries by Standard Industrial Classification (SIC) code. See NR 216 for complete information on listings of industrial activities by SIC and tier. Here is a brief summary of how industries are classified by Tier:
- Tier 1 permits cover various “heavy” manufacturers such as paper manufacturing, chemical manufacturing, petroleum refining, shipbuilding/repair, and bulk storage of coal, minerals and ores.
- Tier 2 includes “light” industries that engage in activities that may contaminate storm water or have materials exposed to storm water. The potential for storm water exposure to industrial materials at these sites, while still a concern, is less than at Tier 1 sites. The Tier 2 group includes:
- Facilities engaged in food processing, furniture manufacturing, paper products, or electronics.
- Non-metallic mineral mining (e.g., sand, gravel, rock, and other aggregate).
- Transportation facilities with vehicle maintenance areas, and other industrial activities listed in NR 216.
The DNR may also allow a classification of “No Exposure” for industrial facilities if the industry has no discharge of contaminated storm water. This exclusion applies to a facility that has no outdoor storage of materials or waste products and that meets all the requirements of the “No Exposure” classification.
See EPA guidelines for Conditional No Exposure Exclusion . The no exposure exclusion is determined on a case-by-case basis at industrial sites where storm water is not contaminated by industrial activity.
To request the no exposure exclusion, an appropriate representative of the facility must file the DNR No Exposure Certification Form #3400-188 found on the industrial storm water permit forms page.
An industry facility granted no exposure status is required to reapply for no exposure every five years to re-certify the facility’s no exposure status.
Types of industrial storm water permits
In Wisconsin, there are two types of Industrial Storm Water Permits, general permits and industry-specific permits.
General storm water discharge permits and requirements
- Tier 1 (Permit Number: WI-S067849-4) - The Tier 1 general permit covers the industries listed in s. NR 216.21(2)(a) , including “heavy” industries such as paper manufacturing, chemical manufacturing, petroleum refining, shipbuilding/repair, and bulk storage of coal, minerals and ores.
- Tier 2 (Permit Number: WI-S067857-4) - The Tier 2 general permit covers industries listed in s. NR 216.21(2)(b) , including a variety of “light” industries such as food processing, furniture manufacturing, paper products, and electronics.
These general permits differ in chemical monitoring requirements, inspection frequency, plan development requirements and the annual permit fee. See ch. NR 216 for a complete list of SIC codes and the corresponding Tiers.
Comparison of Industrial Storm Water Discharge
General Permit Requirements by Tier
|Requirements||Tier 1||Tier 2||No Exposure|
|Identify & Eliminate Non-Storm Water Discharges||Yes||Yes||Yes|
|Develop a Storm Water Pollution Prevention Plan||Yes||Yes||No|
|Document source-areas and implement BMPs per the SWPPP*||Yes||Yes||No|
|Complete Quarterly Visual Inspection*||Yes||Yes||No|
|Complete Annual Facility Site Compliance Inspections*||Yes||Yes||No|
|Perform Chemical Monitoring*||Yes||No||No|
|No Exposure Certification every 5 years*||No||No||Yes|
|Submit an Annual Permit Fee||$260||$130||None|
Industry-specific storm water discharge permits
The industry-specific storm water discharge permits are general permits customized to address potential storm water contamination issues common to a particular industry category. These industry-specific general permits have the same basic elements as the statewide general permits. Three industry-specific storm water discharge general permits have been issued in Wisconsin.
- Dismantling of vehicles for parts selling and salvage (WI-S059145) - This industry-specific storm water discharge general permit covers those facilities with Standard Industrial Code (SIC) 5015 - Motor Vehicle Parts, Used. The requirements for this permit are similar to those of the Tier 1 General Industrial Permit described above. However, Auto Dismantling facilities have the option to participate in a privately-managed Cooperative Compliance Program (CCP) to help oversee permit compliance.
- Recycling of scrap and waste materials (WI-S058831) - This industry-specific storm water discharge general permit covers those facilities with Standard Industrial Code (SIC) 5093 - Scrap and Waste Materials. The requirements for this permit are similar to those of the Tier 1 General Industrial Permit. Similar to the Dismantling of Vehicles Permit, this permit provides the option to participate in a privately-managed Cooperative Compliance Program (CCP) to help oversee permit compliance.
- Nonmetallic mining operations (WI-A046515) and (WI-B046515) - These general permits cover construction sand, gravel, dimension stone, rotten granite, clay pit, crushed stone, and industrial sand operations and processing where wash water, pit dewatering, dust control and non-contact cooling wastewaters are discharged to surface waters or groundwater. These general permits also contain storm water requirements in accordance with ch. NR 216, Wis. Adm. Code.
Summary of general permit requirements
Storm water permits require industries to take action to reduce the exposure of storm water to industrial activities. Each facility must also develop and implement a storm water pollution prevention plan (SWPPP). The SWPPP must be kept at the industrial facility and should include the following items.
- Name and job title of the person(s) responsible for developing and implementing the storm water pollution prevention plan and serving as the facility’s contact.
- A map showing facility boundaries, how storm water runoff flows throughout the facility, the location of activities and materials which may contaminate storm water, and any existing storm water management practices.
- A summary of any information that helps characterize the quality of storm water discharge. Information that illustrates dry weather flow conditions should also be included.
- Potential sources of storm water contamination.
- Status of all non-storm water discharges to the storm water conveyance system which do not currently have a permit issued by the DNR through the Wisconsin Pollutant Discharge Elimination System.
- Control practices that reduce the exposure of storm water to contamination sources. Examples are covering a loading dock or storage area so that storm water does not come into contact with potential pollutants or the use of regular “housekeeping” procedures to keep pollutants away from storm water.
- Identification of residual pollutants that could remain in storm water even after pollution prevention activities have taken place.
- Treatment practices to remove pollutants from storm water if there are no practical ways to control contamination before it occurs.
- A monitoring plan to determine the effectiveness of the facility’s pollution prevention activities.
- A schedule for implementing the pollution prevention plan.
Tier 1 permitted facilities must conduct annual chemical monitoring. Wisconsin Guidance for Industrial Storm Water Sampling provides information on chemical monitoring requirements and methods.