Dredging on Little Lake Butte des Morts Dredging typically occurred during spring, summer and fall months, with hauling of sediment continuing through fall, winter and into spring. The dredging work for the entire project was completed in June 2008, and sediment drying and hauling was completed in January 2009. In-water work consisting of the placing of sand and caps was completed in May 2009. 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 by LLCT 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 units were among the quietest dredges in use, and two operators worked on each dredge. Click here to view a map of Little Lake Butte des Morts and the remediation areas addressed by the LLCT.