General Permit Requirements for Ferrous/Nonferrous Foundries, Casting, Extrusion, Rolling, Galvanizing and Finishing, MO-R203

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 act was amended to include the regulation of certain stormwater classes by NPDES permitting.

Through the NPDES permit program, the Missouri Department of Natural Resources 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 Stormwater 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. 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-R203 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 in the primary metal industry and having SIC codes of 2514, 2522, 2542, 33xx, 34xx, 35xx, 36xx, 37xx, and 38xx may need to apply to the department for Missouri State Operating Permit MO-R203 to discharge stormwater. It is the responsibility of the owner or operator to apply for a MO-R203 permit. Questions regarding applicability of a MO-R203 permit should be directed to the appropriate regional office.

Permit Applications and Fees
Facilities applying to MO-R203 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-R203, application Form E must be submitted at least 30 days prior to the expiration of the MO-R203 along with appropriate fees. If the facility has any questions concerning fees, the facility needs to contact the appropriate regional office.

Permit Requirements
MO-R203 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 aluminum, copper, iron, oil and grease, pH, total suspended solids, and zinc. At this time, the above parameters are monitoring requirements only.

MO-R203 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-R203 does not authorize stormwater discharges within 2 miles upstream of biocriteria reference locations. MO-R203 does not authorize stormwater discharges within 100 feet of a wetland (Class W), major reservoir (Class L2), permanently flowing stream (Class P), or intermittent stream (Class C). 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-R203. The facility shall select, install, use, operate, and maintain the best management practices prescribed in the SWPPP. At minimum the SWPPP shall include best management practices designed to:

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.

Permit Exemptions
Facilities that discharge stormwater directly to a combined sewer system with a department approved Long Term Control Plan [10 CSR 20-7.015(10)] or to a publicly owned treatment works that has consented to receiving such a discharge are exempt from MO-R203 permit requirements.

Important Permit Dates
Mo-R203 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 fee.

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 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