Superfund record of decision (EPA Region 8): Monticello Mill Tailings (USDOE), Operable Unit 3, Monticello, UT, September 29, 1998

This decision document presents the selected interim remedial action for Operable Unit (OU) 3 surface water and ground water at the Monticello Mill Tailings Site (MMTS) in San Juan County, Utah. The selected alternative for the interim remedial action for OU 3 surface water runoff, continuation of ongoing monitoring efforts, and evaluation of a permeable reactive treatment (PeRT) wall through the use of a pilot-scale treatability study. If monitoring results indicate that the interim remedial action is not achieving the objectives of preventing exposure to and reducing contaminants in contaminated ground water, other alternatives will be evaluated from the OU 3 feasibility study