2.1.1 Narrative
2.1.2 Response Actions to Date
Week of 11 Oct:
Continued excavation of Bays 1 through 5 with concurrent installation of shoring to support safely reaching target excavation depth of 30 feet. Excavated soil continued to be stored in containment cells awaiting profile sampling results for disposal. This material will be shipped off-Site for disposal beginning the week of October 23rd. It is estimated that a total 4,000 cubic yards of contaminated soil, and 750 cubic yards of clean overburden has been excavated to date.
The new water treatment control unit was a help to treatment operations. Due to the greater than expected quantity of groundwater needing removal from the excavated bays additional storage tanks needed to be ordered and situated on Site until it could be determined that it was safe to discharge treated water to the nearby wetland. By Friday, 16 October the site hosted approximately seventeen full 20,000 gallon water tanks of treated water. It is believed that the source of all the extra ground water is the area that was excavated and backfilled as part of the EPA Removal Action in 2009. The backfill used to backfill that area has a greater capacity to retain water than does native soil and it is hydrologically connected to the new excavation area. Lab results were received on the morning of Friday 16 October enabling the initial discharge of treated water into the wetland.
During the course of the week it was also discovered that the first three tanks of treated water had pH levels slightly higher than Oregon drinking water standards. These tanks were treated before the original water treatment control unit was replaced and a significant portion of this water, which was used to start up the water treatment system, came from the municipal water system. It is believed based on public advisories that City actions to address a valve failure nearby may have increased the pH of City water. EPA contract crews treated the water to bring the pH down to within acceptable levels. As of the end of this period an estimated 610,000 gallons of water has been treated.
2.1.3 Enforcement Activities, Identity of Potentially Responsible Parties (PRPs)
2.1.4 Progress Metrics
Waste Stream |
Medium |
Quantity |
Manifest # |
Treatment |
Disposal |
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