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 exposureWe’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.