Mealey's (April 20, 2020, 1:09 PM EDT) -- WASHINGTON, D.C. — The nation’s high court on April 20 found that a group of 98 landowners who live on a portion of a Superfund site in Montana can pursue state law claims seeking additional remediation of the site but that any cleanup activities that go beyond those in an agreement between Atlantic Richfield Co. and the U.S. Environmental Protection Agency must be approved by the agency (Atlantic Richfield Co. v. Gregory A. Christian, et al., No. 17-1498, U.S. Sup., 2020 U.S. LEXIS 2405)....