Tacoma's history is rooted in lumber and industry. Near where our house is located, a copper smelter was operated for almost 100 years. Native residents of Tacoma are quite familiar with the history behind the ASARCO smelter, the jobs & revenue it brought to the city, it's closure in 1986, demolishment in 1993, and the legacy of arsenic and lead which the smoke stacks layered into the soil of the surrounding areas. I say "native residents are familiar" because when Sarah and I decided to buy our home, being transplants, we were clueless to the history & controversy of the land. As has been shown on 60 Minutes, ASARCO has been found responsible for environmental pollution at 20 Superfund sites across the U.S. - including the one on Commencement Bay, here in Tacoma.
Now before anyone goes and starts thinking we live on some sort of radioactive wasteland, let me tell you, none of us has grown webbed feet, can shoot lasers from our eyes, or any of that other cool X-Men stuff. If fact, the threat (or at least perceived threat) is quite low. Even so, as a result of a law suit a few years ago, the Army Cops of Engineers was commissioned to provide soil sampling tests and soil remediation (if required) for all homes within a specified area around the old smelter. Our home lies a mere 200 yards inside of that boundary, and when we got a letter in the mail asking if we wanted our soil tested - we responded YES.
We live near the red star.
That letter came in January of 2010. The soil sampling didn't happen for another 6 months. We received the results from those tests just 5 days short of 1 year after the sampling. Who said the government works on it's own time?
To backtrack a bit, this whole thing got me thinking, "Is there an acceptable amount of arsenic?" The answer is a bit more complicated than yes/no, but here's a little bit of info for the geek types out there. The EPA, to my understanding, has no statute regarding the levels of Arsenic in soil, only water. However, it is generally accepted that The concentration of arsenic in soil varies widely, generally ranging from about 1 to 40 parts of arsenic to a million parts of soil (ppm) with an average level of 3–4 ppm. The Army Corps of Engineers set their remediation limits (remediation for the Corps of Engineers essentially consisted of removal of the contaminated dirt, and back-filled with "clean" dirt and grass seed) at 23o ppm. I expected the worst thinking we would be high, around 200, but under the limit.
Results? Our soil is too clean for remediation. As it turns out - we aren't all that bad. Our highest sector tested at 44 ppm with an average right at 30 ppm. Our soil was also tested for lead, remediation standard of 500 ppm - our average was in the low 70's.
What do we do now? Basically, we follow the same procedures your mom told you any time you had been playing outside: leave your shoes at the door and wash you hands!
"Tacoma Smelter Plume" Information from King County Health Services:
More information than you ever wanted from the EPA: http://yosemite.epa.gov/R10/cleanup.nsf/sites/ASARCO
The contractors hired by the Army Corps of Engineers - at work sampling our yard.
A calibrated aluminum digging pole. The canister was approximately 6" deep by 2 1/2" wide
it was a requirement to test ALL soil locations - even in the flower beds...
These guys were pretty good at leaving a minimal footprint. After the hole was dug, it would be filled with "clean" dirt, and the grass patch flipped back on top leaving virtually no indication of the sampling process.
This is what a "remediated" yard looks like during the process. By my estimation, in a 1/2 mile radius form our house, about 1 in 20 homes got all or part of their yard remediated.
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