See Polrep # 2 for Site Description for this Phase II Removal Action.
Release of this POLREP # 8 was delayed while product recovery activities were ongoing and Post-Removal Site Control discussion were occurring with Washington State Department of Ecology.
One EPA OSC, 1 ERT hydrogeologist, 6 ERRS personnel, and 5 START personnel conducted the following activities:
1. EPA returned to the site during the week of March 19, 2007, to complete the Phase II Removal Action, which was stopped in December 2006 for the winter.
2. Once the snow had melted and temperatures had risen above freezing, ERRS received an additional 1,000 cubic yards of top soil and finished the re-grading of the site. Most of the top soil was placed in the north stockpile area, which was where excavated soil was stockpiled before being sent off site for disposal.
3. ERRS also removed the temporary fencing that had been placed around the former treatment area. The fencing had been used to enclose the area of excavation and the recovery wells, but some of the fencing sections fell over during the winter. At the direction of the OSC, the fencing was dismantled and returned to the vendor.
4. In place of the temporary fencing, ERRS placed wood poles around the perimeter of the former treatment area. The wood poles were obtained from stockpiles remaining on the site after the removal action. The poles were placed on the border of the driveway and the back-filled area with the recovery wells to delineate the driveway and to prevent traffic from disturbing the recovery well area.
5. ERRS placed additional gravel to prevent erosion around the culvert that drains into the channel to the south of the former treatment area.
6. Following re-grading, an ERRS subcontractor applied hydroseed to backfilled and re-graded areas, including the former treatment area, the north stockpile area, and a few smaller cleanup areas in the south stockpile area.
7. START was on site to document the removal activities.
8. START was also on site during this week to perform the March 2007 quarterly groundwater sampling event, which is part of EPA's ongoing efforts to monitor groundwater conditions on and around the site.
1. Continue to monitor product-recovery system periodically and remove collected product from passive skimmers.
2. Continue to perform quarterly groundwater sampling and monitoring of the on-site and off-site monitoring wells and neighboring domestic wells under the removal assessment scope of work.
1. ERRS will continue to monitor the product recovery system on a biweekly basis. A local ERRS employee will visit the site every other week to record data about product thickness levels in the recovery wells and to monitor the amount of product recovered by the product recovery skimmers. Data provided by ERRS will be evaluated by the OSC and START to determine the need for any potential system upgrades in summer or fall.
2. START plans to return to the site in June or July to complete the next round of quarterly groundwater monitoring and sampling.
1. ERRS is still having some issues with the product recovery skimmers. There are only two on site in the recovery wells, and only one is completely functional. The other one has small cracks in the bottom and also collects more water than it should. The amount of product observed in the recovery wells has been very low, though, so the skimmers that are available appear to be sufficient. ERRS and START will investigate ways to resolve the equipment issue and will continue to monitor the site for any changes in the amount of free product.
|
