A new map that refines and narrows the extent of the Asarco smelter plume on Vashon Island is good news for a simple reason: It’s based on better science.
When it comes to the region’s arsenic-laced soil, a legacy of nearly a century of copper smelting in the region, the issue isn’t the impact contamination might have on property values. It’s not what we want to hear that matters. What’s needed is accuracy for the sake of health and safety.
The Department of Ecology is to be commended for engaging in an iterative process, hiring someone preeminent in the area of spatial analysis and refining its map as it got better information. Some might find the change in the state’s analysis suspicious. We see it as a kind of transparency that is welcome in a project as ambitious and far-reaching as the state’s effort to clean up residential yards within the boundaries of a 1,000-square-mile plume, considered the largest contaminated site in the state.
State officials hope to begin the project later this year. What that means is that teams will knock on doors at homes that lie within this smaller cleanup service area, ask permission to sample soils and, if they find elevated levels of arsenic in high-use areas — gardens or play areas, for instance — devise a site-specific plan for soil removal or capping.
At most homes, they likely won’t find a problem. Arsenic does not decompose or move downward through the soils; it will remain permanently in the top layers of the soil. But the process of building and landscaping a site often means that arsenic is removed, covered up or significantly diluted. Those houses built after the smelter closed in 1986 likely have seen enough soil disturbance and landscaping to mitigate the effects.
But the situation could be far different at older homes on the island or at places where there’s been little soil disturbance. And lest one think there’s no problem with arsenic, some would suggest you think again. Public health officials are not terribly worried about naturally occurring, or organic, arsenic. But the kind that fell from the sky during the heyday of Ruston’s copper smelting is inorganic, and it’s considered toxic and harmful to children or others who inadvertently ingest it.
The state program — covered by Asarco’s bankruptcy — is providing a remarkable opportunity for islanders to find out what’s happening on their swath of land and address any contamination that is found. Information is a powerful thing. Better yet is information followed up by an action plan.
We’re lucky to be handed this opportunity. We hope many take full advantage of it.