Minnesota Department of Transportation

511 Travel Info

Contaminated Materials

Frequently asked questions



1. Does CMMT drill during winter?

CMMT does not drill during the winter months. There are safety concerns with freezing temperatures, snow plowing activities and ice covered ground surface that cause delays and increased costs. Additionally, the water used to clean the equipment between each sample freezes and prohibits the collection of analytical groundwater samples, and contamination monitoring equipment does not give accurate measurements. The seasonal/winter calendar is Nov 15 - April 1, but can be shorter if there is mild weather.

2. Does CMMT conduct Phase I ESA site walks in winter?

Phase I ESA site walks are not conducted in the winter because many features can not be properly observed due to snow cover and/or dormant vegetation. These features could include a flush-mount monitoring well, stressed vegetation, fill pipes, utility manhole covers and low or depressed area surface dumping.

3. When is the EDD process used?

MnDOT Policy #OP009 Environmental Due Diligence for Property Acquisition details when and why to use the Environmental Due Diligence (EDD) process. In short, MnDOT must perform an EDD evaluation each time it acquires property. This includes, but is not limited to, acquisitions as permanent and temporary easements, fee, lease, Commissioner's Orders, custodial control, rail bank, facilities or from a local unit of government.

4. How can soil be reused?

The reuse of soil anywhere within a project is allowed by the MPCA if it meets the Best Management Practices for the Off-Site Reuse of Unregulated Fill. Soil can also be reused within a project as described with a MPCA approved response action plan (RAP) or under the roadway in the near surface at contamination levels below MPCA Industrial levels as approved by CMMT's project manager.

5. Where can I find an MPCA approved landfill?

MnDOT requires contaminated soil to be disposed of at a Minnesota permitted solid waste or industrial landfill facility as daily cover if it's meets the requirements of daily cover. The MPCA maintains a list of these facilities.

6. How do I submit FOIA request?

The Freedom of Information Act (FOIA) was passed in 1967 to provide the public the right to request access to governmental records. A FOIA request applies to federal agencies. The State of Minnesota has the Minnesota Data Practices Act. To make a request, follow the instructions here.

7. When is a Temporary License Agreement (TLA) required?

The TLA Form is used for water or soil sampling within MnDOT ROW. It will be used to approve work for the necessary collection or sampling of soil and/or water, the traffic control needed and the cleanup and repair of the right of way from that work. It may also be used to install wells for continued water sampling or a perspective buyer's environmental due diligence. A TLA is not required if the company is conducting the sampling under contract with MnDOT to complete the specified work type.

8. Where is information regarding the pre-qualification list?

CMMT uses only companies under work type 5.41 Contamination Inv-Level 1 who are approved through the pre-qualification program.

9. When should the terms: hazardous-, contaminated-, regulated-, unregulated- or clean- soil be used?

Hazardous is used to describe soil that is listed on a F, K, P or U list and are characterized hazardous. These are rarely found on MnDOT projects. Contaminated is used to describe soil that exceeds the MPCA or MDA's values for Industrial land use. This soil is disposed of at a landfill. Regulated is used to describe soil that exceeds the MPCA or MDA's values for Residential land use. This soil is disposed of at a landfill or is reused within the project limits in restricted areas. Unregulated is used to describe soil that meets the MPCA's best management practices for off-site reuse of unregulated fill. This soil can be reused any on the project. Clean is used to describe soil that has sampling data below laboratory detection limits and no debris. The preferred term is Unregulated.

10. What is the difference between MnDOT's OES CMMT vs. RMMT?

The Contaminated Materials Management Team (CMMT) and Regulated Materials Management Team (RMM) are both part of the Environmental Investigation Unit (EIU) within the Office of Environmental Stewardship (OES) at MnDOT. The CMMT identifies, investigates and manages contaminated soil, groundwater and/or vapor. The RMMT identifies, investigations and manages regulated waste such as asbestos, lead paint and treated railroad ties. In general, CMMT does everything below ground whereas RMMT does everything above ground, building demolition, relocation or bridge deck removal/rehab.

11. What is BTB and how should it be handled?

Bituminous Treated Base (BTB) is a label created by MnDOT Materials Office in the 1990's to describe historic former roadway pavements that were constructed with coal tar bitumen as a component. It maybe less than 1 inch up to several feet in thickness, depending on how many historic resurfacing occurred over time. The MPCA allows reuse of BTB. Minnesota Rule 7035.2860 “Solid Waste Utilization Standing Beneficial Use Determination (BUD)” does not differentiate between different types of bituminous. All bituminous can be milled and recycled in accordance with the BUD. MnDOT has a contingency plan for NOT recycling bituminous if it is too soft or has too strong an odor, and is thus not suitable for recycling. If it cannot be recycled, it must be sampled and disposed of in a landfill as a solid waste.

12. Where is information on groundwater discharging permits?

Many projects require a federal National Pollutant Discharge Elimination System (NPDES) permit under the Clean Water Act or a Minnesota State Disposal System (SDS) permit. In Minnesota, the federal NPDES is administered by the MPCA. If there is contaminated groundwater within the project limits that will potentially be discharged during dewatering activities or rainwater that comes into contact with contaminated soil, then the MNG790000 NPDES/SDS permit (Ground Water Pump-Out General Permit) compliance is required. Table 1 of the permit has the discharge limits per contamination parameter, such as diesel range organics and gasoline range organics at 200 ug/L. This permit expires on December 30, 2021.

13. When should trench dams and pipe wrap be used?

A engineering control to stop the potential migration of contaminated groundwater or vapors is required by MnDOT Special Provision 2105 section for Contaminated Soil and Groundwater as determined by the level of contamination identified. Engineering controls are items such as, but not limited to, vapor barrier or pipe wrap installed between native and fill soil materials or trench dams made of clay or bentonite within utility trench at regularly space intervals (i.e.. every 50 feet) and connections leaving existing work area. These items should extend from the base of the excavation to above the high water mark. However, pipe wrap may not be necessary if ductile iron or alternative gaskets are used. All materials must be compatible with known contamination types.

14. Where does CMMT drill and sample?

CMMT drills and collects soil and/or groundwater samples within MnDOT's current rights-of-way, proposed acquisition areas and proposed construction limits. This can include private property with a signed Right of Access form.

15. How do I use the P6 30% checklist?

With the CMMT project manager's approval, add the CMMT Checklist (ESA2499 owner is District Project Manager) and change logic ties from 30% plans to CMMT Checklist task.

16. What if the project won't have 30% plans or construction limits in time for CMMT activities?

Engage with the CMMT project manager to discuss an option to add the CMMT Checklist (ESA2499) to the project schedule. There are risks involved which may require more than 1 mob, increased costs, might not drill and be negative float. Need to involve District R/W.

17. Can P6 durations be changed?

CMMT has many P6 work packages. A couple packages have lengthy durations, such as the ESA packages. The template and standard way of adding these into a project is to use the medium duration. However, some projects are more complex or have less risk. With the approval from the CMMT project manager, the durations can be changed to the high or low template.