Cleanup Activities in Operable Unit 1

Little Lake Butte des Morts, which lies between Lake Winnebago and Appleton, is also known as Operable Unit 1 in the cleanup plan for the Lower Fox River and Green Bay. The Little Lake Buttes des Morts cleanup plan calls for dredging 784,000 cubic yards of PCB contaminated sediment. The final cleanup plan for OU 1 is currently being designed by WTM I and GW Partners, the two paper companies who signed an agreement with DNR and EPA to clean up this portion of the river (see the Administrative Order on Consent here). Two paper companies that have agreed with DNR and the U.S. Environmental Protection Agency (EPA) to design, carry out and pay for the cleanup in this stretch of the river are P. H. Glatfelter Co. and WTM I Co. (see the Consent Decree here).

Cleanup activities at Little Lake Butte des Morts began in June 2004 with the construction of an on-shore sediment treatment site, also called a staging area, on the west shore of the lake.

The site is located on North Lake Street in sight of the U.S. Highway 41-441 interchange, and features an observation deck that's open to the public. The staging area includes a boat dock, a water treatment plant, and a gravel dewatering (or draining) area lined with several layers of special impermeable plastics. On top of this gravel dewatering area are large sediment-collection tubes (called "geotubes") made of a special geotextile fabric that doesn't allow water in but does allow it to seep out (see pictures of the geotubes).

Dredging in Little Lake Butte des Morts started in summer 2004 and continued into early winter until the weather got too cold. It is expected to resume next spring. The dredge is only removing sediment from areas that have been shown through extensive sampling to contain concentrations of PCBs at 1 part per million or more.

The process involves several steps: First, sediment is sucked from the lake bed by the hydraulic dredge and is pumped through a floating pipeline back to the staging area and into the geotubes, where it sits while the water drains out of it. Next, the water is collected from the lined gravel drainage area under the geotubes and pumped into the treatment plant, where it's cleaned with sand and activated carbon treatments to remove contaminants. The clean water is then returned through another pipeline to the lake. Finally, when the sediment is dry enough, it is removed from the geotubes and loaded into lined, covered trucks for transport to the disposal site. The disposal site for sediment from this part of the river is Onyx Hickory Meadows landfill in the Town of Chilton, which is fully licensed for the disposal of sediment containing PCBs. Transportation of the sediment to the in Chilton began in late 2004.

All equipment and phases of the process have been designed to minimize noise and disruption to residents of the area. The public is welcome to visit the cleanup site; an observation deck has been built for that purpose. Also, the paper companies and DNR have made sure the pipeline is clearly marked so boaters on the lake can avoid it, and boater safety information has been made available at the boat ramps, marinas, fishing clubs and bait shops. For more information on boater safety, visit the Little Lake Cleanup Team web site (exit DNR).

This agreement does not address cleanup work for the remaining portions of the Lower Fox River and Green Bay (OUs 2-5); DNR, EPA and the paper companies are engaged in ongoing discussions regarding those plans. The actual cleanup work in OU 1 is being done by contractors for Glatfelter and WTM I (GW Partners) and is expected to take three to six years.

Please click the link below to view a graphical representation of OU 1.
OU 1

Last Revised: Tuesday November 21 2006