This section of the manual is current undergoing review.
This page provides discussion and links to information on regulations that apply to stormwater pond dredging operations. This information on this page comes primarily from the MPCA Dredged materials management website and MPCA guidance, Managing Stormwater Sediment Best Management Practices Guidance (wq-strm4-16).
FAQs
- Is a permit required for stormwater pond dredging/sediment removal projects?
- Is sediment testing required for all stormwater pond dredging projects?
- How many samples do I need to collect?
- What pollutants do I need to test for?
- How do I make sense of lab analysis results?
- What can I do with recovered sediment once I have test results?
- How can I find a facility that will accept sediment recovered from ponds or other stormwater BMPs?
- What about street sweepings?
Discussion and links to information
1. Is a permit required for all stormwater pond dredging/sediment removal projects?
No - MPCA does not require a permit all pond dredging projects. Depending on the scale you pond dredging project, a construction stormwater (CSW) permit may be required, and depending on the location of your project, a permit or notification of work may be required by the local governmental units (LGUs).
For some dredging projects, a State Disposal System (SDS) permit, or Public Waters Work Permit may be required. These are not likely to be needed for maintenance of stormwater BMPs. A brief description is provided below.
SDS Permit
State Disposal System permits are issued by the MPCA. An SDS permit is required for the storage or reuse of material removed from navigational channels, harbors, docks, and similar settings if the volume removed is greater than 3,000 cubic feet. Maintenance of constructed stormwater ponds is unlikely to trigger this requirement. For more information visit the following:
- MPCA Dredged materials management website - DO I need a permit?
- MPCA guidance document wq-gen2-02, Best Management Practices for the Management of Dredged Material
Public Waters Work Permit
Public Waters Work Permits are issued by the Minnesota DNR. Work activities below the ordinary high water level (OHWL) in public waters require a permit from the DNR. For more information visit the Minnesota DNR website, Public Waters Work Permit Program.
2. Is sediment testing required for all stormwater pond dredging projects?
Yes - If you plan to reuse the sediment or dispose of it at a landfill.
MPCA’s Remediation Division soil reference values (SRVs) are used determine where excavated sediment may be used or disposed
- Depending on the type and level of contamination they contain, dredge materials may be classified as level 1, 2, or 3 dredged materials with level 1 representing the lowest risk to human health/least restrictive management options and level 3 the greatest risk/most restricted management options. See guidance in Section 2 of wq-strm4-16 for more information on dredged materials classifications.
- If sediments are found to have significant contamination or are otherwise unsuitable for use as fill, testing is needed to determine whether the sediment can be accepted at a municipal, industrial, or hazardous waste landfill. See MPCA's Landfills website for more information on the different types of landfills.
3. How many samples do I need to collect?
The recommended number of samples to collect depends on the size and shape of the area to be dredged. Guidance on sediment sampling depth, number, location, and collection, storage, and handling procedures is provided in Appendix A of wq-strm4-16.
4. What pollutants do I need to test for?
The recommended scope of contaminant testing will vary based on the following:
- Testing required by MPCA prior to disposal of sediment. This includes concentrations of 17 cPAHs, 10 noncarcinogenic PAHs, and the metals arsenic and copper (Appendix A, wq-strm4-16).
- Consideration of historic and current land use within the pond drainage area.
- Additional testing required by landfill operators - dredged materials classified as Level 3 or pond sediment otherwise not suitable for fill that will be landfilled must meet the material specification of the landfill accepting the material. Contact prospective landfill facilities for site specific testing requirements.
5. How do I make sense of lab analysis results?
MPCA has develop a spreadsheet for summarizing contaminant levels for the required testing described in the first bullet under question 4 above. This spreadsheet can be used to determine whether sediments will be classified as level 1, 2, or 3 dredge materials based on analysis of these pollutants. We have also developed a flow chart which provides an overview of how sediments are classified as level 1, 2, or 3 dredge material based on sediment analysis results.
Contact the MPCA solid waste program for management of pond sediments that contain other pollutants of concern.
6. What can I do with recovered sediment once I have test results?
Guidance on appropriate use of level 1, 2, and 3 dredge material is discussed in Section 2 of wq-strm4-16. Additional sediment characterization may be needed for specific applications within the acceptable use categories.
7. How can I find a facility that will accept sediment recovered from ponds or other stormwater BMPs?
Landfills that may accept contaminated stormwater sediment include:
- Municipal solids waste (MSW) landfills - MPCA maintains a list MSW landfills in Minnesota. That list and additional information are available on the MPCA Landfills website.
- Facilities permitted to accept industrial waste may also be able to accept contaminated stormwater sediments. You can search for permitted solid waste facilities by county using MPCA's What's in My Neighborhood search tool.
8. What about street sweepings?
In 2010, the MPCA completed beneficial use determination for the management and limited reuse of sediment collected through street sweeping. Contaminant testing is not required if sweepings can be screened and managed in accordance with restrictions outlined in the beneficial use guide for sweepings, Managing street sweepings.
Contaminant testing may be required if sweepings cannot be screened, are not suitable for the reuse options outlined under the beneficial use determination and will instead be disposed of at a landfill. See the page Disposal options for street sweeping materials for information and related considerations.