Site testing should occur before building a park | Guest Column | Jan. 27

We believe the installation of a park at the Unocal site should be aggressively pursued, but there are underlying issues that must be addressed before a park is constructed at the corner of Winslow Way and State Route 305.

We believe the installation of a park at the Unocal site should be aggressively pursued, but there are underlying issues that must be addressed before a park is constructed at the corner of Winslow Way and State Route 305.

The site is owned by the City of Bainbridge Island and Kitsap Transit. Both have neglected to test the monitoring wells on site for a few years, therefore, before a park is designed and built, the extent of contamination must be defined.

The state’s Department of Ecology (DOE) has documented that the extent of contamination onsite has not been defined. Once the extent of the problem is defined, then a cleanup method can be selected and implemented.

When environmental work does not follow a logical sequence, we end up with another Strawberry Park site on Bainbridge.

Full definition of contamination was not done before the construction of Strawberry Park, which resulted in a listing on the state hazardous sites list, and will result in additional costs to disturb the site by sampling and completing cleanup mandated by DOE.

We met with DOE on Jan. 24, and were told that there are two potential funding sources to pay for contamination definition and cleanup: the Washington Remedial Action Grant Program (through DOE); and Chevron, which purchased Unocal.

Funding currently exists in this grant program. DOE is in discussions with Chevron regarding financial assistance for sites with substantial soil contamination and groundwater contamination, including the presence of floating petroleum product.

Because petroleum product exists and the site is subject to shoreline regulations, DOE said, the site is a more likely candidate to receive funding sooner than some other contaminated sites.

Large oil companies have recently provided substantial funding of gas station cleanups around the state. Shell and British Petroleum currently fund two full-time employees through DOE, dedicated solely to petroleum cleanups.

It is incumbent upon the city and Kitsap Transit, both of which are responsible for cleanup of the site, to vigorously pursue these funding mechanisms to clean the site before park design and construction begins.

In summary then:

• Hasn’t enough cleanup been done on the site?

We don’t know. The site’s hazard ranking is currently a 2 on a scale of 1 to 5, indicating the toxicity risk is relatively high.

The two main steps to cleaning up a site include defining the extent of contamination, then selecting a remedial (cleanup) method.

State and federal law requires that contamination be defined before selecting a cleanup method. Contamination is defined by sampling the soil, groundwater and surface water, and analyzing them for the constituents used onsite.

Cleanup methods include removal, treatment of contamination with chemicals, or natural attenuation (i.e., allowing natural breakdown of contaminants over time). DOE  wrote a letter in 2003, clearly stating that natural attenuation is not an option until defining the extent of contamination.

About 2,500 cubic yards of near-surface contaminated soil were removed in the 1990s, and 2,000 yards were shipped offsite for disposal.

The remaining 500 cubic yards were treated onsite; a few confirmation samples were collected from this treated material, and that soil was returned to the site surface.

It is not clear if all of that material on the surface is clean. Aside from surface soils, the western creek side of the site requires sampling.

• Why not just build the park and clean the site later?

Construction of the park before defining the extent of contamination and implementing a cleanup strategy is not a good idea because viable cleanup methods may require that the park be removed in order to implement the remedy.

For example, capping the site with clean material or removal of the existing 8,500 cubic yards (source: GeoEngineers 2003) of buried contamination would require complete destruction of the park.

Melanie Keenan and Malcolm Gander are licensed geologists and hydrogeologists who have contributed their time toward numerous environmental conservation studies on the island.