Hello Jim,
In follow up to our recent discussion, I have attached a DRAFT figure showing the general proposed sample locations for the wetland characterization. Below is a general description of the sampling strategy that will be included in the work plan. Please make any necessary comments/revisions or just call me to discuss. My objective is to submit a workplan to you that meets your expectations from the start, or as close as possible to that. I meant to discuss the rationale for not sampling the far side of the wetland channel with you during our phone call. It was my understanding that the product did not reach the far side, but I was not an initial responder so I would like confirmation from you. If that is not the case, let me know and we will add samples there as needed. Also, I anticipate the possibility that follow up sampling may be needed based on the results of the initial samples.
<Draft Excerpt From Wetland Workplan>
Sampling Strategy and Anticipated Locations:
A general strategy for identifying and determining the appropriate number of samples and locations is discussed below. In general, the proposed sample locations are based on previous observations of product and water entering the wetland or field observations at the time of the event. The actual locations will be determined in the field based on the following general strategy. The proposed approximate sample locations are presented on the attached Proposed Wetland Sample Locations map (Figure 2). The sample locations are primarily situated on the embankment above the water level. The highest observed concentrations, if present, are expected to be in proximity to the water level at the time of the release. Note that sample locations A and B are specifically associated with previously observed product/water seeps or flows into the wetland area. These areas are not currently contributing product or water to the wetland. In addition, a sample will be collected for analysis from the identified “Palustrine Forested Wetland” and the “Overland Stormwater Drainage” areas as identified on Figure 2. The remaining sample locations are distributed along the bank of the wetland area for requisite coverage, but will be adjusted based on field screening. The bank of the wetland will be thoroughly field screened using observations and PID readings from the former high-water line, to the water level at the time of the sampling event. Any discrete areas identified with high levels of PHCs based on field screening, will be sampled for analysis. Vertical delineation samples might also be collected as warranted, at locations where high PHC concentrations are observed. If no discrete areas of high PHC concentrations or elevated PHC concentrations are observed, the wetland samples will be collected in proximity to the locations illustrated on Figure 2. The soil condition between and around the sample locations will be thoroughly field screened and documented based on observations and PID readings. If PHCs are observed beyond the current network of proposed samples, the investigation/sampling area will be extended, as warranted, until PHCs are no longer observed. Two sediment sample locations are currently proposed adjacent to the two areas where water/product incursion (A and B) was observed at the time of the release. The sediment samples will be collected from the bottom of the channel using a hand auger. The sampling activities will be performed in general accordance with the MSBA Field Methods and Procedures (FM&P) presented in Attachment B. Quality control samples such as field duplicates, equipment blanks, trip blanks, etc., will be collected in accordance with the Quality Control Plan presented in Attachment C.
Sincerely,
Marty Burck
Licensed Geologist OR, CA, WA
Phone: 855 387 4422