PLAINFIELD TOWNSHIP, Mich. (AP) — A Superfund landfill suspected of chemically polluting a Michigan water system once accepted toxic sludge from a leather tannery that used the same chemical compounds, according to state records and a former truck driver. Sand Lake resident Earl Tefft told MLive that he regularly drove sludge waste from the Wolverine World Wide tannery to the State Disposal Landfill from 1965 to 1966, while hauling for a local pickup service.