Erosion and Sediment Control
- Construction Stormwater (CSW) Permit (MPCA or EPA)
- Is permit coverage active? Ask contractor for proof of permit coverage (could be an email or letter).
- Is the Contractor listed on the permit as the Operator? (see MPCA’s Permit Search page)
- DNR Public Waters Permit
- Is a public waters permit needed?
- Is a water appropriations permit needed (see below)?
- Are there water areas with aquatic invasive species?
- Coordinate with DNR Liaison
- SWPPP amendments
- Have Contractor amend SWPPP immediately after the pre-construction meeting to include: names and certification cards of Erosion Control Supervisor and installer, locations of toilets, staging, spill kits, concrete washout, stockpiles, exit controls, etc.
- Review the plan (together). Does it make sense for contractor’s proposed operations? Are the wetlands, and other environmental commitment delivery clearly shown (see section below)?
- Have contractor document all changes in the form of a SWPPP amendment (write on the plan itself photograph, or other document) and submit within 7 days of when the need for a change was identified.
- Erosion Control Supervisor
- Are they certified? Check the Construction Site Manager Certification List.
- Explain Erosion Control Supervisor Expectations. Refer to 1717 (Quality control) and 2573.3A.1
- Demand proactive professional performance. This person’s job is to keep your project in compliance with the CSW Permit and out of trouble.
- Site Management Plans
- Where are site management plans needed?
- Do plans explain how the contractor will protect the Area of Environmental Sensitivity?
- Do they have contingency plans and materials on site to respond to problems?
- Has plan been shared with DNR Liaison if work is adjacent to public water?
- Erodible Acre Withholding
- Add up acres of soil disturbance
- Withhold from partial estimate payments according to 2574
- Stormwater inspections
- Ensure Erosion Control Supervisor (ECS) is inspecting weekly and after ½ inch rains
- Join the ECS on their inspection occasionally (at least once a month)
- Compare plan sheets to actual conditions – are amendments necessary?
- Inspection reports
- Agree on an inspection report form such as MnDOT’s Inspection Report Templates
- Reports should document:
- whether BMPs are effective
- corrective actions needed, with location and deadline
- corrective actions completed since the last inspection
- condition of all stormwater discharge locations
- Weekly erosion control schedule
- Discuss at weekly meeting
- How does the weather forecast compare to their plans for grading and stabilization?
- Will disturbed soils be worked or stabilized? Has call been made to either the grading contractor or the erosion control contractor?
- Does their schedule meet CSW Permit time frames?
- Perimeter controls
- Verify that perimeter controls aren’t being placed on up-slope perimeters (amend SWPPP if necessary)
- Ensure that perimeter controls (including inlet protection) are in place before any soil disturbance in each area
- Work in water
- Require site management plan, have it reviewed by DNR if public water. Do not allow work to start before plan has been accepted.
- Silt curtain is to be used only while working in water
- Ensure silt curtain is removed from water and redundant perimeter control is installed on shore as soon as work in water is complete
- Dewatering
- Require a dewatering plan showing how water will be cleaned, how scour will be prevented, and how Contractor will respond to problems. Do not allow work to start before plan has been accepted.
- Have contractor monitor frequently (according to spec and CSW Permit timelines) and document observations with photos
- Stop work immediately if sediment discharge occurs
- Stabilization
- Soils stabilized within 7 days or 14 days (see SWPPP narrative)
- Swales/ditches/conveyances within 200’ of outfall are stabilized within 24 hrs
- Slopes draining to public waters during exclusion dates are stabilized within 24 hrs.
- Ditches and concentrated flow areas steeper than 2% need blanket
- Straw Mulch
- Type 3 Mulch must arrive with certification tags attached to each bale. Reject bales that do not have tags attached.
- Straw mulch must be crimped immediately and cover 90% of soil
- Neither Type 1 or 3 Mulch can have visible weeds.
- Hydraulic Mulch
- Hydraulic Erosion Control Products (Hydromulch) must be on the Approved Products List.
- Green hydromulch is not allowed. Product must be blue or dye-free.
- Hydromulch must be applied from two directions and cover 100% of soil
- Rolled Erosion Prevention Products (REPP)
- Blankets and Turf Reinforcement Mats (TRMs) must be on the Approved Products List.
- Plastic netting is not allowed on any blanket (REPP categories 10 – 47).
- Blankets must be trenched, overlapped, and correctly anchored.
- Blanketed areas must be watered for 45 days if plan states that maintenance is required.
- Maintenance
- Perimeter controls are functional and cleaned out when ½ full
- Inlet protection is functional and kept clean
- Exit controls are preventing trackout, and any trackout is cleaned up by end of day or sooner
- Stabilization is functioning and repaired/supplemented as needed
- Pollutant Prevention
- Spill kits present and stocked
- Secondary containment on all pollutant sources
- Toilets are anchored and have secondary containment
- containment of overspray for bridge washing and painting, covering any materials that could pollute stormwater, and keeping stie clean and free of litter.
- concrete washout facilities are managed appropriately
- Spills and sediment releases
- Report all spills and sediment releases to MN Duty Officer (use Spill Reporting Template).
- Clean up spills immediately after reporting
- Begin coordinating access to off-site spills immediately after reporting
- Clean up off-project spills within 7 days of gaining permission
- Permanent Stormwater Treatment
- Ensure basin is protected with extra stabilization and sediment control until all contributing drainage areas are fully vegetated
- Test infiltration rate of underlying soils before placing filter media on infiltration basins
- Test infiltration rate of filter media after placing filter media and establishing vegetation on both infiltration and filtration basins
- Verify that water drains away within 48 hrs after a rain
- Enforcement
- Contact OES and OCIC if contractor is not following stormwater permit or related spec requirements
- Review stormwater compliance enforcement tools on the DOT_Construction Eng & Supv Teams channel or on the Construction Site Management website.
- Permit Close-out Requirements
- Ensure permanent stormwater treatment is functioning
- Ensure sediment is removed from stormwater treatment and conveyance system
- Photograph vegetation to document 70% cover of perennial vegetation (not weeds, annuals, or cover crop)
- Have all temporary sediment controls removed, and any resulting disturbance repaired
References: Permit requirements; Specifications 1717, 2106, 2573, 2574, 2575, and 3876-3890; Schedule for Materials Control