Clapper, Patti, Schweizer and Mason

In an area of northwest Washington, there is naturally-occurring asbestos that has been carried downstream of Swift Creek and ended up along the banks of the Sumas River.  It is thought that beginning in the 1930’s there was a landslide in the Sumas Mountain caused by heavy rain, which exposed and broke down a certain type of rock that contained asbestos fibers.  When scientists sampled the creek’s banks in 2006, it was found to contain up to 4 percent asbestos and averaged 1.7 percent. 

Each year the landslide brings up to 120,000 cubic yards of material into Swift Creek and the Sumas River.  There has been great potential for exposure along the river’s banks because it is popular for outdoor activities such as hiking and horseback riding.  And for years, people have hauled away the material along the banks for use as yard and driveway fill.

In January 2009, even more residents were affected when there was a flood that brought this material-containing asbestos onto the properties boarding the Sumas River.  Water flooded onto farmers’ fields and lawns and even into basements.  The United States Environmental Protection Agency (EPA) took samples from one resident’s affected property and nearby, which revealed three to eleven percent asbestos.  Testing also revealed asbestos in samples taken from this same resident’s basement.   

State Department of Health personnel reviewed years of cancer data and determined that there was no higher incidence of lung cancer or mesothelioma in the affected area than in the general population.  However, it has not been determined if the material-containing asbestos has been present along the Sumas River banks since the 1930’s or is a more recent occurrence. 

As asbestos-related diseases can take ten to forty years to manifest, if the presence of asbestos containing material is more recent, it can take decades for an abnormally high incidence of asbestos-related diseases to appear.  The Agency for Toxic Substances and Disease Registry has set up a year-long monitoring program.  For more information, read the article by Craig Welch, “A flood of asbestos: How much should residents worry?” in The Seattle Times, Sept. 4, 2010, Section A1.  See also http://yosemite.epa.gov/r10/cleanup.nsf/sites/swiftcreek for more up to date information.