General Mills/Henkel Corp. Superfund Site

MPCA Citizens’ BoardInformation Item

February 25, 2014

Chemical Disposal 1947-1962

Former General Mills Facility2010 East Hennepin Avenue

Minneapolis

Generalized Groundwater Contamination

Water Table

Generalized Vapor Intrusion

Dissolved contamination in groundwater

Groundwater Contamination

Soil Gas Investigation 2012-2013

Public Involvement• Two Public Meetings November 12, 2013

• Five Community Group Meetings

• “Office hours” sessions

• MPCA Project website

• E-mail distribution list for interested parties

• Widely covered in local media

Sub-slab Sampling

Building Mitigation

Current Status as of 2/19/14

Current StatusSub-slab Sampling

• 236 properties sampled

Sub-slab Sampling Results

• 126 properties over 20 ug/m3

Mitigation Systems

• 56 installed and verification testing complete

• 30 installation process begun

Additional Remedial Actions

Questions & Discussion

Soil and Groundwater Cleanup• 1981“absorption pit” removed addressing the soil

contamination.

• 1984 Response Order by Consent between MPCA and General Mills

• 1985 Extraction and Treatment of Contaminated Groundwater began.

• 2010 Groundwater system turned off. TCE concentrations below the cleanup concentrations established in the Consent Order

November 6, 2013 Mailing to Residents