October 4, 2017

Jason Hegdahl

Cascade Corporation

2201 NE 201st Ave.

Fairview, OR 97024

RE:  EW-16 Monitoring Conversion; Eastside Conveyance Line Decommissioning Request

East Multnomah County TSA Remedy ECSI No. 1479

Dear Mr. Hegdahl,

The Oregon Department of Environmental Quality (DEQ) has reviewed a document entitled EW-16 Monitoring Conversion; Eastside Conveyance Line Decommissioning Request, East Multnomah County TSA Remedy ECSI No. 1479, dated September 12, 2017, prepared on your behalf by Geosyntec Consultants.

DEQ approves the work proposed in this document and appreciates the conversations with Cindy Bartlett who provided additional clarification and supporting documents. Please keep us informed of progress for this scope of work.

Please feel free to call me with questions.

Sincerely,

Kenneth Thiessen CEG

Northwest Region Cleanup Section

cc:  Cindy Bartlett, Geosyntec Consultants

 Nick Garson, The Boeing Company

 Chris Kimmel, Landau Associates  

ECSI #1479