The St. Regis Paper Co. operated a wood treatment plant in Cass Lake from 1958 to 1985. The area was placed on the Superfund National Priorities List in 1984 because of soil and groundwater contaminants, with the Minnesota Pollution Control Agency as the lead agency.
Initial cleanup was done and monitoring equipment installed in 1985 by Champion International Corp., then the owner/operator of the wood treatment facility (the current owner is International Paper), with oversight by the Minnesota Pollution Control Agency.
EPA became the lead agency in 1995. After site reviews, soil sampling and a risk assessment, EPA determined that contamination remained on the site.
Interim cleanup took place in 2005. Eight permanent cleanup alternatives were then developed, from which EPA proposed a plan in August 2011 that would remove or cover contaminated soil, pave roads and continue monitoring soil and groundwater on the site. The Record of Decision on that plan was delayed in October 2011 after strong opposition to the proposed plan.