Where state environmental agency was adequately supervising remediation efforts by corporation to clean up PCB contamination of plaintiffs’ land, district court did not abuse discretion in denying supplemental injunctive relief under federal statutes.The 7th U.S. Circuit Court of Appeals affirmed a decision by Chief Judge James D. Peterson, Western District of Wisconsin.William and Nancy Liebhart own property near Watertown, Wis. In 1953, Heavy-Duty Electric Company announced plans to convert a building located in …