General Permit Requirements for Chemical and Lubricant Manufacturing, MO-R23A

Water Protection Program fact sheet
Division of Environmental Quality Director: Ed Galbraith

The original 1948 Federal Water Pollution Control Act, now known as the Clean Water Act, has seen many changes. Among these changes were the 1972 amendments, which included the establishment of the National Pollution Discharge Elimination System (NPDES) in Section 402 of the act. "NPDES prohibits [discharges] of pollutants from any point source into the nation's waters except as allowed under an NPDES permit." In 1987, the CWA was amended to include the regulation of certain stormwater classes by NPDES permitting.

Through the NPDES permit program, the Missouri Department of Natural Resources (department) has received authorization to regulate point sources that discharge pollutants into waters of the state. Point sources are generated from a variety of municipal and industrial operations, including treated wastewater, process water, cooling water, and stormwater runoff from drainage systems. The NPDES Storm Water Program has been in place since 1990 and regulates discharges from municipal separate storm sewer systems (MS4s), construction activities, industrial activities, and those designated by the Environmental Protection Agency due to water quality impacts.

Missouri Industrial Permits
The EPA delegated authority for the NPDES permitting program to the department in 1974. Although the federal government oversees and reviews the Missouri State Operating Permit program, it is the state which issues and enforces these permits. Missouri’s stormwater regulations are located in 10 CSR-20.6.200. These laws require that permits be issued to certain industrial facilities for their discharges. A permit may be required for discharges of water contaminants to waters of the state or to a Municipal Separate Storm Sewer System (MS4). If the activity does not discharge any water contaminants to either, no permit is needed. If it does discharge water contaminants to one or both or if the industrial activity is listed among the regulated categories and meets certain requirements as outlined in 10 CSR 20-6.200(2), a permit is required. 

An industrial activity may be excluded from stormwater permitting if the activity does not expose materials to stormwater as stated in 10 CSR 20-6.200(1)16. Qualified permit holders as well as new applicants that qualify must submit a completed “No Exemption Certification” form (EPA form 3510-11) to the department. This form is available online at:

Who Needs a MO-R23A Permit
Stormwater and wastewater regulations use the Standard Industrial Classification (SIC) system to determine if an industry is regulated under the law. This classification system was devised by the U.S. Office of Management and Budget to cover all economic activities. Facilities having SIC codes of 2992 (Lubricant Manufacturing) and 28xx (Chemical Manufacturing), except 282x, 2869, and 287x, may need to apply to the department for Missouri State Operating Permit MO-R23A to discharge stormwater. It is the responsibility of the owner or operator to apply for a MO-R23A permit. Questions regarding applicability of a MO-R23A permit should be directed to the appropriate regional office.

Permit Applications and Fees
Facilities applying for MO-R23A for the first time must submit application Form E (MO 780-0795), which can be found at, along with the appropriate fees. After issuance of the permit, fees will be assessed annually. To request a renewal of MO-R23A, application Form E must be submitted at least 30 days prior to the expiration of MO-R23A along with appropriate fees. If the facility has any questions concerning fees, the facility needs to contact the appropriate regional office.

Permit Requirements
MO-R23A requires facilities to conduct quarterly sampling of stormwater runoff from all outfalls and to submit quarterly reports to the appropriate regional office. If a discharge does not occur during the reporting period, report as no-discharge in the report. The parameters to be tested for include chemical oxygen demand, chemicals listed in 40 CFR 122 Appendix D, oil and grease, pH, and total suspended solids. At this time, the above parameters are monitoring requirements only.

MO-R23A does not authorize stormwater discharges within 1,000 feet upstream of waters identified as: a losing stream, sinkhole, or other direct conduit to groundwater; a designated use of drinking water supply; critical habitat for endangered species; or an Outstanding State Resource Water. MO-R23A does not authorize stormwater discharges within 2 miles upstream of biocriteria reference locations. MO-R23A does not authorize stormwater discharges within 100 feet of a major reservoir (Class L2) or permanently flowing stream (Class P) and within 500 feet of an intermittent stream (Class C) or wetland (Class W). Facilities within the watershed of an Outstanding National Resource Water are authorized to only discharge uncontaminated stormwater or operate as a no-discharge facility. The above waters are identified or described in Missouri Water Quality Standards (10 CSR 20-7.031).

A Stormwater Pollution Prevention Program (SWPPP) must be developed when applying for MO-R23A. The facility shall select, install, use, operate, and maintain the best management practices prescribed in the facilities SWPPP. At minimum, the SWPPP shall include best management practices designed to:

  1. Prevent spillage or loss of fluids, oil, grease, etc. from vehicle maintenance, equipment cleaning, etc.
  2. Provide collection facilities on-site and arrange for proper disposal of waste products, including but not limited to, petroleum waste products and solvents.
  3. Store all paint solvents, petroleum products, petroleum waste products (except fuels), and storage containers such as drums, cans, or cartons so that these materials are not exposed to stormwater. Facilities must provide spill prevention, control, and countermeasures to prevent any spills of these pollutants from entering waters of the state.
  4. Provide good housekeeping practices on-site to keep solid waste from entering waters of the state.

The SWPPP shall require that all involved personnel be trained in material handling and storage, and housekeeping of maintenance areas. Upon request, proof of training must be submitted to the department.

To the extent required by law, discharges to waters of the state shall not cause a violation of Missouri Water Quality Standards (10 CSR 20-7.031), including both specific and general criteria.

Important Permit Dates
Mo-R23A is issued on a five-year cycle. Important dates of each permit are:

Transfer of Permit
A permit may be transferred to a new owner by submitting an Application for Transfer of Operating Permit (MO 780-1517), which can be found at, along with the appropriate fees.

Termination of Permit
General permits may be terminated when activities covered by the permit have ceased and no significant materials are stored in such a way as to come into contact with stormwater. When general permit termination is sought, the permittee must submit Form H, (MO 780-1409), which can be found at

Site-Specific Permit
If requested by the owner or operator, a facility may apply for a site-specific permit. A site-specific permit takes into account the individual characteristics of the site. In addition, the department may determine that the quality of waters of the state can be better protected by requiring the owner or operator of a facility to apply for a site-specific permit. For questions or guidance regarding the need for a site-specific permit or to begin the application process for a site-specific permit, the facility should contact the appropriate regional office.

Map of Missouri Department of Natural Resources’ Regional Offices with Contact Information
The regional office map is available online at

For More Information
Missouri Department of Natural Resources
Water Protection Program
P.O. Box 176
Jefferson City, MO 65102-0176
800-361-4827 or 573-751-1300 office
573-526-1146 fax