November 21, 2002
Mr. Ted McCall
McCall Oil and Chemical Corporation
5480 NW Front Avenue
Portland, Oregon 97210
RE: Supplemental RI Work Plan
McCall Oil Site
ECSI No. 134
Dear Mr. McCall:
Thank you for submitting the November 4, 2002 Conceptual Supplemental RI Work Plan for the McCall Oil Site. The Department of Environmental Quality (DEQ) accepts the work plan with the following comments.
1. The work plan proposes actions to evaluate a data gap concerning ambient water quality criteria (AWQC) for certain polycyclic aromatic hydrocarbons (PAHs) that were exceeded at riverbank well MW-8. Based on groundwater monitoring data collected through March 2002, the sample from riverbank well MW-7 also exceeded AWQC for benzo(a)anthracene. Therefore, the evaluation of potential impact of site groundwater on the Willamette River should include the region around MW-7 and MW-8.
2. Source control evaluations for Portland Harbor sites must evaluate groundwater contamination under the “fish consumption” exposure pathway. The following riverbank groundwater monitoring locations at the McCall site exceed DEQ’s Table 20 fish consumption water quality criteria of 0.031 µg/L for total PAHs: EX-2, EX-3, EX-5, MW-5, MW-7, and MW-8.
3. Coordinate your proposed bathymetric survey with such data collected by the Lower Willamette Group (existing data from multiple LWG surveys may be useful for your evaluation).
4. During our meeting on May 29, 2001 (see July 24, 2001 memo from John Edwards), we discussed measures to address PAH-contaminated stormwater observed at catch basin S-3. In your September 24, 2001 status report, McCall acknowledged DEQ’s request to consider placing sediment screens in site catch basins to prevent contaminated sediment from discharging to the river (particularly at location S-3). DEQ requests an update on the progress of these measures, including catch basin sediment removal/characterization, placement of sediment screens, and continued stormwater quality data.
5. The draft Portland Harbor Source Control Strategy uses five times the AWQC to screen storm water concentrations for impact to the Willamette River (the direct AWQC is used to screen groundwater). This is consistent with storm water benchmarks established in the 1200Z permit. All four storm water samples collected at the McCall site in December 2000 exceed five times the fish consumption water quality criteria, but only storm water sample S-4 exceeded this standard in the second sampling event in March/April 2002. The S-4 sample location is discharge from an oil/water separator in the northeastern bulk petroleum portion of the facility. Contaminant sources discharging to the oil/water separator and/or the operation of the separator should be evaluated to determine if additional measures are required to achieve a discharge screening level of five times the water quality criteria. The December 2000 samples from S-3 exceeded the screening criteria for dissolved copper and zinc. DEQ requests another sampling of storm water at locations S-3 and S-4 for PAH and total and dissolved metal analyses to confirm whether or not storm water contaminant concentrations have been reduced.
Please call me at (503) 229-5326 if you have any questions, particularly if any DEQ comments or the format of your response requires further discussion.
Sincerely,
Tom Gainer, P.E.
Project Manager
Cleanup & Portland Harbor
cc: Eric Blischke, CU/PH
John Edwards, Anchor Environmental