The Cottage Grove facility manufactured PFAS from the 1940s to 2002. In response to PFAS contamination of the Mississippi River and surrounding area, 3M stated the area will be "cleaned through a combination of groundwater pump-out wells and soil sediment excavation". The restoration plan was based on an analysis of the company property and surrounding lands. The on-site water treatment facility that handled the plant's post-production water was not capable of removing PFAS, which were released into the nearby Mississippi River. The clean-up cost estimate, which included a granular activated carbon system to remove PFAS from the ground water was $50 to $56 million, funded from a $147 million environmental reserve set aside in 2006.