If you want to learn how to better control erosion and improve compliance with your Municipal Separate Storm Sewer System (MS4) permit, you'll want to attend the 2025 Minnesota Erosion Control Association Conference & Trade Show, Jan. 28-30, 2025, in St. Cloud, Minnesota. 

MPCA and city staff will be presenting a MS4 Training, Documentation, and TMDL Pre-Conference workshop on Jan. 28. Conference sessions (Jan. 29-30) will cover MS4-Start to Finish and NPDES Compliance Update: Construction and MS4, among other topics. 

For more information, CLICK HERE. Please register by Friday, Jan. 10, 2025. 

Reducing winter salt use does not compromise safety and it helps keep our freshwater lakes and streams from the harmful effects of chloride. To highlight both the problems and solutions to salt pollution, Jan. 27-31, 2025, has been designated Winter Salt Week. MPCA is a proud partner of Winter Salt Week which features daily live streams from ecologists, public works staff, and policymakers from across the United States. Everyone can learn more about the environmental toll of de-icers, private industry successes, actions that states are taking, and how individuals can get involved!

Learn about the speakers and register at www.wintersaltweek.org, then tune in starting Monday, Jan. 27th at 12:30pm CST.

The MPCA Chloride reduction program is hosting a special event for the Friday, Jan. 31, community events day. Join us online at 11am CST for the 2-hour Smart Salting for Community Leader’s workshop. Please register in addition to Winter Salt Week events to receive the workshop link.

For additional questions about these events, chloride or the MPCA’s Smart Salting Trainings, email [email protected] .

As with salt in our meals, a moderate amount of salt in a water softener isn’t necessarily a bad thing. For many Minnesotans who live with hard water, that salt works to lather their soap and stop the buildup of scale in their appliances.

Also, as with salt in our meals, too much salt in a water softener is harmful. It drains wallets, strains backs, and is toxic for the environment. And it’s often not necessary to use much salt in a water softener.

“People don’t often pay attention to the settings on their water softeners,” said Brooke Asleson, who coordinates the MPCA’s chloride reduction program. “Most of the time, they’re still on the factory setting with the highest chloride discharge.”

CLICK HERE to read the whole story. 

A comprehensive geodatabase reflecting total maximum daily load (TMDL) wasteload allocation (WLA) areas for MS4s has been completed! Instead of accessing 90 zipped files through a Sharebase site, the new geodatabase has been checked for accuracy, streamlined, and will be updated as new TMDLs with MS4 WLAs become approved by the US EPA. Stormwater Manual link with more information: Additional resources for completing the TMDL form - Minnesota Stormwater Manual

Direct link to where they are stored in the MnGeo Commons: TMDL Wasteload Allocation Areas for MS4s - Resources - Minnesota Geospatial Commons

Additionally, the MS4 Stormwater Mapping Tool has been updated to better reflect 2020 MS4 General Permit language. It displays the TMDL WLA areas described above if you don’t have GIS capability. It also has a new link: Municipal Separate Storm Sewer System (MS4) Permit Requirements (2024)

Contact Anna Bosch at [email protected] with any questions about either resource.

Industrial stormwater permit holders must ensure stormwater samples meet proper holding times and temperature preservation requirements for their stormwater samples. In most cases this means the sample must be cooled to ≤ 6 ° Celsius.

For reference, holding time and temperature requirements can be found online in the Code of Federal Regulations linked here: 40 CFR 136.3. Accredited labs are required to identify when samples do not meet the proper preservation or holding time requirements.  Ideally, the lab will contact you upon receiving samples when preservation requirements are not met. In those cases, permittees should attempt to gather another sample in that same monitoring period in order to have a sample that properly meets the preservation requirements.

If a new sample cannot be taken, the permittee should indicate that no sample was taken on the compliance monitoring report and select “other” as the reason. Then, report the result of the analysis in the comment field of the monitoring report as well as a description of the preservation/procedure deficiency. The sample result should not be used when calculating the benchmark value. Permittees must take action to ensure future similar issues do not recur. Please routinely review lab reports to check for qualifiers indicating preservation requirements were not met.

For more information, visit the MPCA Industrial Stormwater web page. 

In Oct. 2024, the Minnesota Pollution Control Agency’s (MPCA) Industrial Stormwater (ISW) Program held virtual informational meetings that specifically focused on new requirements for certain facilities that support the MPCA’s efforts to identify and reduce sources of Per- and polyfluoroalkyl substances (PFAS) to the environment. The ISW Program received several questions and comments during and after the informational meetings.

In response, the ISW Program made the following changes to its proposed 2025 NPDES/SDS ISW General Permit (2025 Permit) and No Exposure Certification (NEC) policy:

Update to the NEC policy and timeline: As discussed during the informational meetings, all facilities with a primary SIC Code associated with PFAS as identified in Appendix D of the draft 2025 Permit which are seeking NEC must complete four separate PFAS stormwater monitoring events prior to certifying as no exposure. To meet no exposure, PFAS monitoring results must be below the thresholds identified in Table I below. The MPCA is modifying its timeline for these affected facilities by providing additional time to complete the PFAS monitoring prior to being required to apply for the 2025 Permit. By Dec. 21, 2025, the required facilities must have completed their PFAS monitoring and analysis and apply for NEC or permit coverage.  If PFAS results are at or above the thresholds identified, then the facility must obtain 2025 Permit coverage.

Table I. PFAS Thresholds for NEC

Update to PFAS method requirement: All facilities with a primary SIC Code associated with PFAS as identified in Appendix D of the draft 2025 Permit will be required to monitor for PFAS. During the informational sessions, MPCA discussed that both monitoring and analysis of a facility’s PFAS samples must be completed in compliance with the current version of the U.S. EPA’s Method 1633. The MPCA has modified this permit requirement, now recognizing a facility may utilize any version of the U.S. EPA’s Method 1633 when sampling and analyzing for PFAS.

Please see the ISW webpage, https://www.pca.state.mn.us/business-with-us/industrial-stormwater, to view the recordings and presentation slides and other “meeting resources” from the Oct. 2024 informational meetings copies