Per the discussion at the March 1, 2017 TTWG meeting, here is a list of references regarding PCBs and sediments in the Spokane River. The newer studies contain a reference to where the data can be found on the EIM on the “Publication and Contact Information” at the beginning of the document.
This document: https://fortress.wa.gov/ecy/publications/documents/1103013.pdf
Has a summary of all of the PCB data that has been collected up to 2007. See page 30.
This document: is the Urban Waters data, mostly stormwater sediment.
There is an additional dataset of 8 Urban Waters samples that were collected in 2013 (sediment and seeps) which is in the final stages of upload to EIM. I will send the link to download that data when it is ready.
Here is an eclectic mix of all reports that I could find on the publications database on this topic. Some of these reports are quite old and the conditions that they were measuring may have changed (mostly due to clean ups and elimination of the major PCB sources).