Quality Assurance Project Plan:  Spokane River Atmospheric Deposition Study for PCBs is now at https://fortress.wa.gov/ecy/publications/SummaryPages/1603112.html .

There is currently a data gap for the atmospheric deposition of polychlorinated biphenyls (PCBs), and toxics in general, in eastern Washington.  The only studies that exist for the atmospheric deposition of PCBs in Washington State come from the Puget Sound region.Filling this data gap is an important first step in determining the significance of the role that PCBs in atmospheric deposition play as a source of PCBs to the Spokane River watershed and ultimately to concentrations found in the Spokane River.This study will measure seasonal PCB concentrations and flux in dry deposition and bulk (wet + dry) deposition in the Spokane River watershed.  Dry deposition will be measured by analyzing PM10 (particulate matter ≤ 10 microns) from a high volume sampler located in an urban area of Spokane.  Bulk deposition will be collected with passive samplers at two urban locations and at a regional background location.  Samples will be analyzed with high resolution method EPA 1668c for PCB congeners.  Sampling will commence in early 2016 with quarterly collection periods over the course of one year (through early 2017).

Secondary objectives to be addressed by this study include:

• Determine if the Spokane Waste to Energy facility is a potential source of PCBs to atmospheric deposition by modeling PCB emission data using AERMOD, a plume dispersion model.
• Provide data for estimating the contribution of PCBs in bulk atmospheric deposition to stormwater in Spokane’s Cochran stormwater basin.  The City of Spokane will be collecting PCBs in stormwater from the Cochran basin starting in spring of 2016.

If you have questions, please contact Brandee Era-Miller at 360-407-6771 or at bera461@ecy.wa.gov.