This Administrative Order for Remedial Action is issued to Atlantic Richfield Company for the remediation of the Fluvial Tailings Remedial Design Unit (RDU) and the Regional Water Waste & Soils Operable Unit (OU). Studies have documented the presence, release, and threat of release of arsenic, cadmium, lead, zinc, and copper at the flucial Tailings RDU. The Fluvial Tailings RDU is also a source of releases or threat of releases of hazardous substances or pollutants or contaminants into ground water beneath and surrounding the area.