In July 2007, questions regarding a clay-like material along a shoreline in Lake Linden, Michigan were brought to the attention of the Western Upper Peninsula District Health Department (WUPDHD) and Michigan Department of Community Health (MDCH).
Samples collected of the material by Michigan Department of Environmental Quality (MDEQ) showed levels above direct contact for metals (lead as high as 78,000 ppm*) and PCBs (as high as 12.4 ppm*).
*At this site, direct contact criteria for lead is 400 ppm and 4 ppm for PCBs.
Prior sampling in 2004 and 2005 were below health based levels. In recent years, lake levels have fallen to nearly historic lows and have exposed this new area.
In response to MDEQ's sample results, WUPDHD cordoned this area of the shoreline.
On July 25, U.S. EPA Emergency Response Branch (ERB) assistance was requested. Between July 25 and August 1, ERB collected samples in the cordoned area and along a 1/2 mile area to determine the extent of contamination. ERB sample results from the cordoned area correlate with results collected by MDEQ. Results from the 1/2 mile area are pending.
Further delineation of sediment contamination will be conducted the week of August 6.
An Emergency Time-Critical Removal is being initiated to remove contaminated soil in the cordoned area. Further action is contingent on pending analytical and results of sediment sampling.
The clay-like material is unrelated to stamp sands. U.S. EPA Remedial Branch is currently working on issues related to stamp sands and information collected during the removal action will be shared.
Lake Linden was recently delisted from the Torch Lake NPL. The near historic drop in lake levels has exposed this new area.
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