RESPONDENT IS LOCATED APPROXIMATELY 7 MILES WEST OF BUTTE MT-ADJACENT TO SILVER BOW CREEK. THE PLANT BEGAN OPERATION IN 1900 & CONTINUED UNTIL 1951. IN ADDITION TO FRAMING MINE TIMBERS, THE PLANT WAS USED TO TREAT TIMBER WITH ARSENICALS AND CREOSOTE. VARIOUS SAMPLIHG EVENTS AT THE SITE REVEAL EXTREMELY ELEVATED LEVELS OF ARSENIC AND HEAVY METALS, SUCH AS CADMIUM, COPPER, LEAD AND ZINC. VOLATILE ORGANIC COM- POUNDS SUCH AS ETHYLBENZENE AND TOTAL XYLENES WERE ALSO FOUND. THE STATE ISSUED AND ADMINISTRATIVE ORDER TO RESPONDENT IN 1989. RESPONDENT EXCAVATED AND SHIPPED MOST OF THE CONTAM- INANTS TO THE CHEM SECURITIES LANDFILL IN OREGON. DESPITE THE EFFORT, THE SITE STILL REMAINS HIGHLY CONTAMINATED. THE ACTUAL OR THREATENED RELEASE OF ONE OR MORE OF THESE HIGHLY HAZARDOUS MATERIALS PRESENTS AN IMMINENT AND SUBSTAN- TIAL ENDANGERMENT TO THE AREA.