SEDIMENT Dredging
The majority of the cleanup project involved dredging sediment containing PCBs from the lake bottom and transporting it via a pipeline into very large mesh bags (called geotextile tubes) in our main staging area at 1475 N. Lake Street. These tubes were used to drain the water from the dredged lake bottom sediment. That water was then treated at our water treatment facility and returned to the lake through a clean water return pipe. After the sediment had been dewatered in the tubes, it was placed into sealed dump trucks, which were then covered with tarps for transport to the disposal site.
Photo of one of the dredges that operated up to 24 hours a day, six days a week on Little Lake Butte des Morts.
The dredges used had highly sophisticated Global Positioning Systems (GPS) that aided them in getting to the right spots for removing sediments containing PCBs above the level established by the WDNR and EPA.
The map below shows the remedy areas, including dredged locations, for Little Lake Butte des Morts (OU1).
