Missouri

Missouri Department of Natural Resources
Water Pollution Control Branch
National Pollutant Discharge Elimination System Stormwater Program
1101 Riverside Drive
Jefferson City, MO 65101

Missouri Code of State Regulations 10CST 20-6.200

(V1) (VI) The date and duration (in hours) of the storm event(s) sampled, rainfall measurements of the storm event which generated the sampled runoff, and the duration between the storm event sampled and the end of the previous measurable (greater than one tenth inch (0.1") rainfall) storm event (in hours), at least one-tenth inch (0.1") of rainfall per storm water event are required to be considered a valid storm water event. The reporting rainfall station, if possible, should be within one (1) mile of the sampled outfall and shall be capable of providing rainfall measurements in at least tenths of an inch

MOR13 - Textile and Apparel/Printing and Publ. effective 5-30-2013 thru 5-29-2018

Sampling and reporting may be required by the Department, in that case, the Department will specify specific requirements

MOR203 - Fab. Metal, Light Industrial

effective 9-1-2014 thru 8-31-2019 Stormwater samples shall be collected once per quarter within the first 60 minutes of discharge occurring as a result of precipitation events of 0.1 inches or greater. Precipitation events include rainfall as well as run-off from the melting of frozen precipitation.

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOR22A - Lumber and Wood Primary

effective 9-1-2014 thru 8-31-2019 Stormwater samples shall be collected once per quarter within the first 60 minutes of discharge occurring as a result of precipitation events of 0.1 inches or greater. Precipitation events include rainfall as well as run-off from the melting of frozen precipitation.

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOR22B - Wood Treaters , effective 9-1-2015 through 8/31/2020

Stormwater samples shall be collected once per quarter within the first 60 minutes of discharge occurring as a result of precipitation events of 0.1 inches or greater. Precipitation events include rainfall as well as run-off from the melting of frozen precipitation.

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOR22C - Lumber and Wood (Secondary)

effective 11/1/2013 thru 10/31/2108 Stormwater samples shall be collected within the first 60 minutes of discharge occurring as a result of precipitation events of 0.1 inches or greater. Precipitation events include rainfall as well as run-off from the melting of frozen precipitation.

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOR23A - Chemical Mfg. , effective 11-1-2015 thru 10-31-2020

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOR23D - Plastics and Rubber Mfg.

There are no regular sampling requirements with this permit, but the department may require sampling and reporting

MOR23E - Biodiesel Manufacturing effective 5-23-2013 thru 5-22-2018

Magnitude: greater than 0.1 inches

Interval Between Storms: n/a

MOR240 - Agrichemical Facilities- SIC 5191, effective 5-1-2014 thru 4-30-2019

Magnitude: n/a

Interval Between Storms: at least 72 hours

MOR60A - Motor Vehicle Salvage

effective 11/1/2013 thru 10/31/2018 Stormwater samples shall be collected within the first 60 minutes of discharge occurring as a result of precipitation events of 0.1 inches or greater. Precipitation events include rainfall as well as run-off from the melting of frozen precipitation.

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOR80C - Motor Freight Transportation: effective 10-5-2012 thru 10-4-2017

This permit requires yearly sampling but primary requirement of this permit is the SWPPP. There are benchmarks that are considered necessary to protect existing water quality and shall not be exceeded during discharges resulting from a precipitation event exceeding 0.1 inches during a 24-hour period.

MOR80F - Airports: effective 10-5-2012 thru 10-4-2017

This permit requires yearly sampling, but the primary requirement of this permit is the SWPPP. The sampling should take place the first time runoff occurs after the use of deicers. If deicers are not used at the facility, sampling may take place at any time during the year.

MOR80H - Solid Waste Transfer

effective 9-1-2014 thru 8/31/2019 Stormwater samples shall be collected once per quarter within the first 60 minutes of discharge occurring as a result of precipitation events of 0.1 inches or greater. Precipitation events include rainfall as well as run-off from the melting of frozen precipitation.

Magnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOG50 - Sand and Gravel Washing

No mention of sampling

MOG69 - Dredging Lakes/River Harbors

Effective 3-14-2013 thru 3-13-2018
No mention of sampling

MOG69 - Dredging Lakes/River Harbors

No mention of sampling

MOG698 - Dredging and aggregate mining on the Missouri and Mississippi Rivers

Effective 3-14-2013 thru 3-13-2018
No mention of storm type for sampling

MOG84 - Clay Pits, effective July 1, 2016 thru June 30, 2021

NMagnitude: greater than 0.1 inch

Interval Between Storms: n/a

MOG97 - Yard Waste Compost Sites, effective 11-30-2012 thru 11-29-2017

Monitor once/quarter during the first hour after a discharge from a rainfall event greater than 0.5 inch in a 24-hour period

Sign Up Today to Receive Your Email Alerts Sign Up