Thursday, September 2, 2010

Around the Sound: Future land use and Rayonier cleanup levels

by Rebecca Lawson, regional Toxics Cleanup Program manager

In my July blog “Questions from Olympic Environmental Council’s forum on Rayonier”, I shared some of the complex questions we heard at that event. Several forum participants had questions related to the future use of the Rayonier property and how it might affect cleanup levels for the Study Area. This same question came up during our comment period for the cleanup agreement with Rayonier.

What are cleanup levels?

Eliminating all risks at a contaminated site often is not possible. “Clean” generally means that a site is cleaned up enough that contamination no longer poses an unacceptable threat to human health and the environment. That point is the cleanup level. Cleanup levels are set for each contaminant at a site, and they are set for each medium (soil, groundwater, surface water).

Pathways of exposure

We’re interested in soil, groundwater, etc. is because they are possible pathways of exposure for both humans and other living things. For example, contamination in soil could be accidentally swallowed or inhaled. Contamination in surface water could impact the fish and shellfish we eat.

Cleanup levels also depend on contamination pathways

It gets even more complicated… Ecology isn’t just concerned about what’s on the soil surface—we’re also looking at what’s in groundwater, how soil might impact groundwater, and how groundwater might contaminate surface water. Often, the most stringent cleanup standard is for protecting surface water.

What does land use have to do with cleanup levels?

In rare cases, Ecology may allow less protective soil cleanup levels to protect only against direct soil contact at industrial sites. This is because vulnerable populations such as children will not have direct exposure to soil at the site. However, any other use—residential, commercial, schools, parks—requires a more stringent cleanup level. You may have heard this called an “unrestricted land use” soil cleanup level. The industrial cleanup level may not be appropriate for the Rayonier cleanup.

The Rayonier site

In our March blog about the three-year cleanup timeline, we posted a diagram showing how contamination in the soil could pollute Port Angeles Harbor. If this is the case, surface water cleanup levels could drive the cleanup, making the choice between industrial and unrestricted land use a moot point.

Keep in mind…

We won’t be able to set cleanup levels until we have more information about contamination! Rayonier is currently collecting the data needed for these decisions.

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