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

This guidance is intended to assist agrichemical facility owners and operators with understanding the National Pollutant Discharge Elimination System permitting process in Missouri. While this guidance is helpful in applying for a permit, it does not contain all the information and details that may be necessary. In addition, this document does not cover the permit requirements, and therefore, permittees must read their permit carefully. Facility owners are encouraged to contact the department early in the planning stage if questions or unusual circumstance arise. In addition, the applicant should be familiar with the applicable state laws and regulations.

Permit Applicability
The first step in the permit process is to determine if a permit is required. A permit will be required if the facility meets the definition of an agrichemical facility.

Any site, with the exception of chemical production facilities, is defined as an agrichemical facility if bulk agrichemicals are stored in nonmobile containers or dedicated containers for more than 30 consecutive days per year. The thresholds for bulk agrichemicals are outlined in Table 1.

Table 1. Bulk Agrichemicals: Stored or transported in individual containers of quantities greater than:




5,000 pounds net dry weight

100 pounds net dry weight


500 U.S. gallons

56 U.S. gallons

Agrichemical Facility Regulatory Requirements
Requirements for agrichemical facilities are found under RSMo 644.026 and 644.036 and in state regulations under 10 CSR 20-2.010, definitions, 10 CSR 20-6.010, permit requirements and 10 CSR 20-8.500, design guides.

Air Permitting
An agrichemical facility may need a construction or operating permit from the department’s Air Pollution Control Program. Air permits are required for the construction or modification of an air emission source at certain levels of emissions. Air construction permits allow a facility to construct and operate an air emission source and are required prior to construction of the air emission source. An air operating permit, if required, is needed after operations commence. The level of air permitting depends on the potential emissions of the facility or project. More guidance about air permitting is available on the department’s website at, or contact the Air Pollution Control Program’s Permit Section at 573-526-3835.

Construction Permits
New, expanding or remodeled agrichemical facilities must apply for a construction permit at least 60 days prior to planned construction. The application must include:

Such a facility would need to apply for a site-specific operating permit. Additional information about antidegradation is available on the department’s website at:

To avoid the expenses involved with an antidegradation review and a site-specific operating permit, new facilities should be constructed and operated as no-discharge systems. No-discharge means that storm water collected in secondary or operational containment structures must be land applied, used in the dilution of agrichemicals, or hauled to a permitted wastewater treatment facility.

Minor changes may qualify for an exemption to the requirements of a construction permit. These requests are evaluated on a case-by-case basis. Construction permits are issued for one year and may be renewed one time.

Operating Permits
New, expanding or remodeled agrichemical facilities that have received a construction permit must also apply for an operating permit, unless they qualify for the no exposure exemption as described in the next section.

Three operating permits are available.

No-Exposure Exemption
If an operation is completely under roof and has no exposure to rainfall, including the load-out area, it can apply for an exemption to the operating permit requirements under a “no-exposure” exemption. Please note that a construction permit is still required. After the facility is constructed, the owner must send the department a letter requesting authorization to operate the facility, an engineering certification and a completed EPA Form 3510-11, No Exposure Certification for Exclusion from NPDES Storm Water Permitting. This form is available online at The exemption is reevaluated every five years.

Permit Renewal
All operating permits have an expiration date. The department will send a renewal application to current permit holders during the year preceding the permit expiration. The applicant is required to submit a renewal application at least 180 days before the permit expires. If the applicant has submitted a timely application, the permit continues in the event the department fails to take action upon the renewal application prior to the expiration date. Send no fee with the renewal form.

Land Disturbance Permits
Land disturbance permits are required for storm water discharges from the construction sites of agrichemical facilities if the area to be disturbed will total one acre or more for the entire project. This permit must be obtained prior to any land clearing or grading. The land disturbance permit requires installation of best management practices to limit soil erosion and sediment movement during construction activities. A general permit is available for this activity.

Permit Transfer
To transfer a permit, fill out Application for Transfer of Operating Permit, found online at This is signed by both the previous and new owners.

Annual Fees
The department will bill facilities annually, but payment must be made regardless of whether a bill is received.

For More Information Air Permitting Missouri Department of Natural Resources Air Pollution Control Program P.O. Box 176, Jefferson City, MO 65102 573-751-4817 or 800-361-4827

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

Well Drilling Questions Missouri Department of Natural Resources Wellhead Protection Section P.O. Box 250, Rolla, MO 65402 573-368-2165