Renard Isle is a man-made island, or confined disposal facility (CDF) in the lower Green Bay, just northeast of the mouth of the Fox River (Wisconsin).
Formerly called Kidney Island, it is 55 acres constructed in 1977 by the U.S. Army Corps of Engineers as a disposal site for dredged materials taken from the Fox River and Green Bay harbor entrance channel.
During the mid 20th century, paper mills producing a PCB containing carbonless copy-paper began contaminating the waters.
[2] Since the channel in the lower Fox River and Green Bay harbor entrance needed to be maintained to provide a suitable depth for ship traffic, dredging is done to remove sediment at the bottom.
And since that sediment is contaminated with PCBs that do not naturally biodegrade, Renard Isle was constructed to house those dredge spoils.