What is Industrial Stormwater? 

Any stormwater (rain, flood waters, etc.) which comes into contact with materials or equipment used in, or produced from, industrial activities before leaving the industrial site is considered industrial stormwater. 

Any industrial facility which meets these criteria are subject to State and Federal regulations to maintain water quality by monitoring and managing potential pollutants through Best Management Practices (BMPs). Such pollutants may include heavy metals, oils, salts, or other chemicals. 

Simply put, industrial stormwater is ensuring good house-keeping practices on industrials sites to keep our waters safe and clean. 

• Industrial Stormwater Fact Sheet 

Do You Need a Permit? 

Any facility which has been assigned a primary SIC code or narrative activity must apply for industrial stormwater permit coverage under the SC Industrial General Permit or certify for a No Exposure permit. 

Stormwater discharges associated with industrial activity are required to be covered under an NPDES permit. You can view a description of Stormwater discharges associated with Industrial Activities to see if your facility requires a permit. The Department may also designate other facilities as requiring a permit, particularly where there is a potential for stormwater contamination. 

Primary SIC Code and Narrative Activities 

Primary SIC code(s) can be found on federal tax forms for the industrial facility. The forms which typically contain the SIC code(s) are the Schedule C or C-EZ, Form 1065, Form 1120, or Form 1120-S. Otherwise, the business will be classified by narrative activities. 

You may use the following links to:​ 

• Find your SIC code​
• Convert NAICS code to a corresponding SIC code​
• 29 Sectors of Industrial Activities 

Narrative Activities 

If rather than a SIC code your facility is classified using a narrative activity, you must still apply for permit coverage. You may use the table shown to identify any or all narrative activities which pertain to your facility. 

Regulated Industrial Activities 

Not Authorized​ 

• Wastewater discharges from industrial sites are not considered stormwater discharges and require a separate wastewater permit.​ 

Not Required​ 

• Wastewater permits which already cover stormwater discharges waives the require to apply for a separate industrial stormwater permit.​
• In addition, if your facility was not assigned a primary SIC code or narrative activity, no industrial stormwater permit is required. 

Certify No Exposure 

If any and all industrial materials are located within a storm-resistant shelter and are protected from rain, snow, snowmelt, and/or runoff then a facility may certify for no exposure. These materials may include, but are not limited to: material handling equipment and activities, raw materials, intermediate products, by-products, final products, or waste products. Certifying as no exposure negates the need for a permit, however a No Exposure Certification form and fee must be submitted every five years in place of the permit. Failure to maintain this certification or no exposure conditions constitutes noncompliance with the IGP, State, and Federal regulation. Certifying for No Exposure exempts your site from the following permit requirements:​ 

• creating and maintaining a stormwater pollution prevention plan​
• paying annual fees​
• submitting annual reports​
• monitoring​ 

Assess for Pollutants 

All facilities are responsible for determining if their site contains any of the following significant materials or industrial activities as possible sources of pollutants. They must also determine if rain, snow, snow melt, or runoff ever come in contact with any of these materials. If so, the facility must obtain an Industrial Stormwater NPDES permit under the IGP. The facility may not certify for no exposure. 

Create a SWPPP 

A Stormwater Pollution Prevention Plan (SWPPP) must be developed prior to applying for permit coverage and placing an industrial facility into service. This SWPPP acts as a living document which can be updated to match facility conditions, and serves as a guideline for maintaining compliance with the IGP, State, and Federal regulations. Each SWPPP must include the following information: 

• Facility description​
• Facility map(s)​ with any outfall locations
• SWPPP personnel
• Potential pollutants sources
• Industrial activities
• Pollutants ​
• Spills and Leaks
• Non-stormwater discharges
• Salt storage​
• Sampling Data
• Description of control measures
• Schedules and Procedures (including employee training, inspection schedules, and sampling schedules) 

Other requirements​ 

• Review SWPPP annually and document modifications.​
• Make the SWPPP available to the MPCA upon request.​
• Provide annual reports that reflect current conditions and changes. 

Industrial Stormwater SWPPP Template 

Choose BMPs 

BMPs are best management practices used to prevent illicit discharges from facilities to ensure compliance with State and Federal regulations. Some of the most effective types of BMPs are simply good housekeeping and moving materials indoors in storm-protected facilities to prevent exposure to stormwaters. These can be considered non-structural BMPs. Other BMPs may be structural and installed outdoors where materials are exposed to stormwaters to prevent pollutant runoff. It is important to consider whether materials can be stored indoors or what BMPs may be appropriate if this solution is not feasible.  

Wherever possible, limiting exposure to stormwater is the most cost effective and reliable method of management. Non-structural BMPs must be implemented prior to applying for permit coverage, while structural BMPs may be installed within the first year after applying for permit coverage. 

Apply For, Modify, or Terminate Your Permit 

If your facility requires an industrial stormwater permit, you will need to complete and submit a NOI form. The 2022 Industrial General Permit (IGP) requires all permittees to submit NOI applications electronically. All electronic applications must be submitted through ePermitting for stormwater coverage. Previous versions or “.pdf” versions of the NOI form will not be accepted starting July 1, 2022. You must have an ePermitting account and have an original Certifier Agreement on file with SCDES to submit the request electronically. If you have not set up an account and submitted an original Certifier Agreement, please do so now. An ePermitting account is necessary before submittal of the Certifier Agreement. Your ePermitting account must be linked to your site to access the electronic forms.  

Permit applications and certifications are now required to be conducted electronically, as per recent EPA ruling. Our state uses ePermitting for all Industrial Stormwater permitting.​ 

In order to submit these applications, facility owners and operators must also become certified to sign documents electronically by hand-signing and mailing an original copy of the Certifier Agreement to our office to keep on file. Only once the agreement is received will applicants be able to sign and submit documents electronically.​ 

Meet Requirements 

Once permit coverage is obtained for an industrial facility, it is the responsibility of the owner and operators to ensure that additional permit requirements are being met and recorded appropriately in their SWPPP. The following are additional requirements of industrial facilities: 

Annual Reports 

These reports must be submitted via ePermitting and should contain records of monthly inspections, employee training, TMDL and impaired waters review, reports of spills and methods taken to clean said spills, good housekeeping protocols and maintenance records, sampling records as needed, changes to contact information, and others.  

Employee Training 

Training should be sufficient enough to inform employees of safety procedures, BMP operation and maintenance, spill management, how to prevent contamination, discharge sampling and monitoring procedures, and emergency response to environmental hazards. 

Training should be conducted annually for any employee who play a role in the implementation of the SWPPP, who install, maintain, or inspect BMPs, who conduct discharge monitoring, or who work in any industrial activities covered by the permit. 

Employee training must be documented in the SWPPP by recording the name of the instructor and all attending employees and the date the instruction was given.  

Monthly Inspections 

At least one inspection of industrial sites must be conducted each month with more frequent inspections occurring for larger sites or sites with multiple significant materials or industrial activities. In addition, at least one inspection must be conducted for each runoff event that occurs on the site. 

Inspectors should consider: 

• Does the SWPPP match the current site conditions? (I.e. Are all materials located where they should be? Are all structural BMPs in place where they should be? Are all of the outfalls properly identified?)
• Have new significant materials or activities been added to the site that need to be recorded in the SWPPP and reported?
• Are the BMPs effective at controlling material and activity exposure and stormwater runoff?
• Are any visible contaminants seen in any stormwater during runoff events? 

Impaired Waters Assessment 

It is the responsibility of all industrial facilities to determine if their site discharges to any impaired waterbody. Each year, the facility must confirm the current status of their receiving waters by checking the list of impaired waterbodies for the State. If it is determined that a receiving waterbody has been listed on the most current 303(d) or TMDL list, the facility must begin monitoring for the corresponding pollutant of concern within 180 days following the listing of the waterbody. Monitoring results must be recorded in the SWPPP and reported in each Annual Report. 

Monitoring and Reporting 

Sampling and/or monitoring is required of all industrial sites to ensure that illicit discharges are not occurring from the site during runoff events. The type and frequency of sampling events may vary depending on the sector for which the facility is classified under. A minimum of one sample must be taken within 30 minutes, or as soon as practicable, of a measurable storm event leading to runoff from an outfall.  

There are four types of required monitoring which may apply to an industrial facility: 

• Quarterly benchmark monitoring
• Annual effluent limitations guidelines monitoring
• Impaired waters monitoring
• Other required monitoring as required 

All monitoring data collected must be submitted in an approved format. Only numeric effluent limitations data must be reported on a Discharge Monitoring Report (DMR) once per year. Benchmark monitoring results only need to be reported when specifically required. 

Numeric Effluent Limitations Based on Effluent Limitations Guidelines 

Notice of Termination 

Completion and submittal of a Notice of Termination (NOT) is required when any of the following occurs: 

• The property is sold
• Activities are no longer present that would require a stormwater NPDES permit. 

Starting July 1, 2022, NOTs must be requested through ePermitting. 

Fees and Renewals 

There is an annual fee of $75 for coverage under the general permit. The fee must accompany the NOI. Fees are based on the fiscal year of July 1st through June 30th. There is no prorating of the fee for coverage for a portion of the year. The annual fee is billed about the middle of August each year, for continuing coverage. 

Coverage under the general permit is automatically granted seventeen (17) days after the postmark of the NOI unless the Department notifies the applicant differently. The Department has the authority to request the submission of the SWPPP for review and approval before granting general permit coverage, or at other times. Alternately, the Department has the authority to require an individual permit application be submitted for issuance of an individual permit in lieu of granting general permit coverage. 

No Exposure Certification 

There is a $350.00 fee due with the no exposure certification form. Once approved, no exposure certification is good for five years. At that time, resubmittal of the form and fee will be required.