The MPCA has developed procedures for vapor intrusion mitigation and public communication work that will be used by MPCA and our contractors for doing these aspects of vapor intrusion work. The procedures and documents were developed working closely with MDH, environmental consultants under contract to MPCA and expert practitioners in radon mitigation.
Vapor intrusion guiding principles
The vapor intrusion guiding principles are the basis for the more detailed direction and guidance outlined in the vapor intrusion BMP’s.
- Vapor Intrusion can impact indoor air quality, potentially creating health concerns.
- To have a vapor intrusion risk there must be an occupiable building and soil vapor contamination.
- Variations in soil vapor concentrations can be caused by many factors that vary seasonally such as soil moisture, frost, depth to groundwater, etc. Because of this, a minimum of two seasonal sampling events — during heating and non-heating seasons — from multiple sampling points are needed to decide there is no vapor intrusion risk.
- To be protective and account for uncertainties, mitigation decisions are based on the possibility of health risks from vapor intrusion.
- Effective public communication is essential to doing vapor intrusion work well.
- Documenting vapor investigation and mitigation decisions on maps prepared in a consistent format is an effective way to communicate the presence of a vapor intrusion area of concern and building mitigation status to a variety of stakeholders.
- The effectiveness of a mitigation system needs to be verified with confirmation testing.
- Expedited action is needed when there is increased vapor risk to sensitive people present AND exposures to contaminants above health-protection goals or greater potential for such exposures.
- A plan is needed to assure continued operation of mitigation systems.
- Future property owners need to be notified of the presence and need for continued operation of mitigation systems or unresolved vapor intrusion risks.
- When there is a source creating vapor contamination, the source should be addressed with remediation, if feasible.
Investigation and building mitigation decision best management practices
- Best Management Practices for Vapor Investigation and Building Mitigation Decisions (c-rem3-06e)
- Appendix A — Minnesota Soil Gas List — TO15 (c-rem3-06f)
- Appendix B — Sampling Methodology
- MPCA Sub-slab Sampling Methodology — This video demonstrates the steps for collecting a representative sub-slab vapor sample from beneath a building's concrete floor slab.
- Appendix C — Recommended Number of Samples per Building Foundation Size (c-rem3-06h)
- Appendix D — Vapor Intrusion Building Survey Form (c-rem3-01a)
Building mitigation best management practices
- Attachment A — Pre-Mitigation Diagnostic Checklist
- Attachment B — Active Mitigation System Installation Checklist
- Attachment C — Post-Mitigation Diagnostic Checklist
- Attachment D — Post-Mitigation Confirmation Sampling Checklist
Public communication best management practices
Listed below are topics for cleanup guidance information. Select the topic to see the listing of related documents.
- Intrusion screening values and vapor intrusion (c-rem3-14) — ISV plain language fact sheet.
- What is an ISV? (c-rem3-14a) — How intrusion screening values are calculated.
- Interim ISVs Short Guidance (c-rem3-12)
- 2009 ISV spreadsheet — Any revised Interim ISVs listed in the "Interim ISVs Short Guidance" above should be used instead of the values listed in 2009 ISV spreadsheet.
- Spatial data standards for remediation programs
- Coming soon, new SRV guidance
- Coming later, new land use framework
Soil Leaching Value (SLV) guidance
The SLV guidance document and the spreadsheet containing SLVs are new guidance from the MPCA Remediation Division for evaluating risks posed by leaching of contaminants in soil to groundwater.
Corrective Action Design (CAD) for use at Superfund, Resource Conservation and Recovery Act, and VIC Programs
Effective July 1, 2011, the CAD guidance developed earlier by the Petroleum Remediation Program will be utilized at remediation sites, as set forth in the following policy document:
- Underground Storage Tank and Petroleum Remediation Quality Assurance Program Plan
- 1-01 Petroleum Remediation Program General Policy (c-prp1-01)
- 1-02 MPCA Information Request Policy (Web only)
- 1-03 Spatial data collection at petroleum remediation sites (c-prp1-03)
- You as a Responsible Party in the PRP (c-prp1-04)
- Leak Site Ownership Form (c-prp6-07)
- Procedures for Assessing Contamination at Large Above-ground Storage Tank Sites
- 2-01 Reporting of Petroleum Releases
- 2-02 Light Non-Aqueous Phase Liquid Management Strategy (7/2010)
- 2-03 Light Non-Aqueous Phase Liquid Recovery Report
- 2-04 Recent Releases at Petroleum Tank Sites (c-prp2-04)
- 2-05 Release Information Worksheet
- Petroleum Release Notification Follow-up
- 2-08 Petroleum Release Notification Follow-up Template
Soil excavation and treatment
- 3-01 Excavation of Petroleum Contaminated Soil
- 3-02 General Excavation Report Worksheet
- 3-02a Corrective Action Excavation Report Worksheet
- 3-03 Land Treatment of Petroleum Contaminated Soil
- 3-04 Application for a Petroleum Contaminated Soil Land Treatment Site (Form A)
- 3-05 Application to Land Treat Petroleum Contaminated Soil at an Approved Site (Form B)
- 3-06 Notification of Spreading Petroleum Contaminated Soil at a Land Treatment Site (Form C)
- 3-07 Soil Monitoring results for Land Treated Petroleum Contaminated Soil (Form D)
- 3-08 Permit Application for a Land Treatment Facility
- 3-09 Current Pre-Approved Petroleum Contaminated Land Treatment Sites
- 3-13 Composting of Petroleum Contaminated Soil
- Facts About Composting Petroleum Contaminated Soil
- 3-15 Land Treatment General Information
- 3-16 Assessment of Petroleum Contamination at Closed Sites
- 3-17 Thin Spreading Small Quantities of Petroleum Contaminated Soil
Site investigation and risk evaluation
- 4-01 Soil and Groundwater Assessments Performed during Site Investigations (c-prp4-01)
- 4-01a Vapor Intrusion Assessments Performed during Site Investigations (c-prp4-01a)
- Vapor Intrusion Interior Building Survey Form
- 4-01c Intrusion Screening Values (c-prp4-01c)
NOTE: Effective 1/15/14, the dichlorodifluoromethane (Freon-12, CFC-12) ISV has been withdrawn due to lack of adequate toxicity data.
- Vapor Intrusion Technical Support Document
- 4-02 Risk evaluation and site management decision at petroleum release sites (c-prp4-02)
- 4-03 Assessment of Natural Attenuation at Petroleum Release Sites
- 4-04 Soil Sample Collection and Analysis Procedures (c-prp4-04)
- 4-05 Groundwater sample collection and analysis procedures (c-prp4-05)
- 4-06 Investigation Report (c-prp4-06)
- 4-08 Monitoring Report (c-prp4-08)
- 4-09 Groundwater investigations in Karst areas (c-prp4-09)
- FAQs about Investigation and Remediation of AST Facilities
- Assessment of sensitive groundwater conditions (c-prp4-18)
- Investigation Requirements for Ethanol-blended Fuel Releases
- 7-01 Corrective Action Design and Implementation (c-prp7-01)
- 7-02 Conceptual Corrective Action Design Report
- 7-03 Focused Investigation Work Plan
- 7-04 Focused Investigation Report
- 7-05 Pilot Test Work Plan
- 7-06 Pilot Test Report
- 7-07a Remediation System Detailed Corrective Action Design Report
- 7-07b Excavation Detailed Corrective Action Design Report (EDCAD)
- 7-08 Remediation System Operation Monitoring Report (RSOM)
- 7-09a Air Emission Controls
- 7-09b Air Emissions Screening Spreadsheet
To evaluate risks from trichloroethylene (TCE) of tetrachloroethylene (PCE) please contact the MPCA project team for a revised spreadsheet.
- 7-10 Discharging Contaminated Groundwater
Effective June 2011, analytical methodology for the vast majority of remediation sites will be the short list of seven cPAHs. However, under certain site conditions the extended list of 25 cPAH compounds will be recommended. The policy document provides background and situations where the extended list of 25 cPAH methodology applies.
The MPCA will consider, on a case by case basis, disposal in appropriate Minnesota landfills of soils contaminated by mercury at concentrations which are both no greater than 4 ppm and non-hazardous. This will apply to soils from remediation and redevelopment sites. Any such disposal must occur in accordance with industrial solid waste management plans. For further discussion of this issue, please see the program management decision document below:
The MPCA has developed the following policy and guidance for the offsite reuse of excess soil or fill material for brownfield redevelopment sites. For unregulated fill material, please refer to:
For fill material with contaminant levels greater than the MPCA's most conservative risk-based standards, please refer to the following documents that detail procedures for brownfield redevelopment sites (that are enrolled in the MPCA's Voluntary Investigation and Cleanup (VIC) and/or Petroleum Brownfields (PB) programs) to move regulated fill from one VIC/PB site to another VIC/PB site, subject to the terms and conditions as outlined:
- Brownfield Program Services
- Brownfield Program Response Action Plans
- Guidance Document #9: Guidance for Investigating and Remediating Asbestos-Containing Waste Materials
- Asbestos Fact Sheet
- Guidance Document #8 Phase 1 Investigation (vic-gd8)
- Guidance Document #11 Phase II Investigation Work Plan
- Guidance Document #12 Phase II Investigation Report
- Affidavit Concerning Real Property Contaminated with Hazardous Substances (c-rem4-02)
- Environmental Covenant and Easement
- Consent of Mortgage Form