Friday, August 16, 2013

Around the Sound: Work Underway at the Rayonier Mill Cleanup Site

By Marian Abbett, Site Manager, Toxics Cleanup Program

Soil stockpiles at the Rayonier Mill site. July 2013
You may have noticed more activity recently at the Rayonier Mill cleanup site in Port Angeles. Rayonier removed the unused guard shack at the entrance to the site. The shack was in the way of new fencing and a gate that the City of Port Angeles (city) plans to build for the Olympic Discovery Trail. Rayonier removed asbestos-containing material from the guard shack before tearing it down. Rayonier will continue removing old structures into the fall, which will improve safety.

Long-term soil stockpile management work to begin

Rayonier will also soon begin moving soil that they have stockpiled on the site. The soil in the stockpiles is from trenches the city dug on the mill property for their combined sewer overflow (CSO) project.

The soil is currently in 13 mounds that are covered with plastic (see photo). The plastic was a temporary cover that Rayonier used during construction to prevent erosion by wind and rain. However, it would likely not last for several years under harsh weather conditions.

Now, Rayonier needs to arrange the stockpiles for long-term management. Until final site cleanup, the new system will:
  • Minimize direct contact with contaminated and potentially contaminated soil.
  • Keep wind and rain from eroding the soil by stabilizing it with a grass cover.
  • Ensure that rainwater that seeps into the stockpiles doesn’t leave the stockpile area.

Stockpile management plan

Click on figure for larger image.
Rayonier will push the soil in some of the 13 stockpiles together to make mounds that are shorter and have less steep sides (see figure). This will make them easier to mow and maintain. They will put plastic sheets between stockpiles so that soil from different piles does not get mixed when they are pushed together.

Then Rayonier will plant grass seed on the new stockpiles. They will inspect the stockpiles every week until the grass is growing well. Once there is a good grass cover, Rayonier will inspect the stockpiles monthly through the winter, and then every three months to make sure soil is not eroding and that all soil is covered with grass.

Pilot stockpile testing

To find out what general types and levels of contamination are in the stockpiles, Rayonier did some pilot sampling of the existing stockpiles. This very general pilot sampling gave Rayonier and Ecology enough data to develop a plan for managing the stockpiles. Before final site cleanup, Rayonier will develop a plan for fully sampling and cleaning up the stockpiles.

Based on the pilot sampling, most of the stockpiles have some metals and dioxins slightly above the screening levels developed for the upland data summary report. One composite sample found some heavy oil contamination and one found carcinogenic polycyclic aromatic hydrocarbons (cPAHs) above the screening levels.

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