THE RESPONDENTS ENTER INTO THIS ADMINISTRATIVE ORDER ON CONSENT TO PERFORM WORK IDENTIFIED BY EPA WHICH WILL PARTIALLY CHARACTERIZE THE RELEASE OR THREAT OF RELEASE OF HAZARDOUS SUBSTANCES AT THE SITE IN ORDER TO PROTECT THE PUBLIC HEALTH OR WELFARE OR THE ENVIRONMENT. MILL TAILING PILES AND WASTE ROCK PILES ARE FOUND WITHIN THE SITE. MILL TAILING IS THE ROCK DEBRIS REMAINING AFTER MILLING AND SEPARATION HAS REMOVED THE METAL AS CONCENTRATES FROM THE ORE. TAILING IS GENERALLY FINE-GRAINED PARTICLES. MINE WASTE ROCK CONSISTS OF MINE DEVELOPMENT ROCK AND LOW GRADE ORE REMOVED TO GAIN ACCESS TO AN ORE BODY AND OFTEN DEPOSITED NEAR ADITS AND SHAFT OPENINGS. SOME OF THE CONSTITUENTS, ALSO KNOWN AS HEAVY METALS, FOUND IN MILL TAILING AND WASTE ROCK ARE HAZARDOUS SUBSTANCES. SMELTER OPERATIONS PREVIOUSLY OPERATED AT THE SITE ARE ANOTHER POTENTIAL SOURCE OF HEAVY METAL CONTAMINATION. FUGITIVE DUST MAY BE GENERATED BY WIND EROSION, EARTH MOVEMENT DURING CONSTRUCTION, OFF-ROAD VEHICLES, AND VEHICULAR TRAFFIC ON DIRT AND GRAVEL ROADS. DATA COLLECTED PURSUANT TO THE WORK PLAN IS INTENDED FOR USE IN EVALUATING THE POTENTIAL FOR MIGRATION OF METALS THROUGH VARIOUS ENVIRONMENTAL MEDIA AND POTENTIAL ASSOCIATED TO PUBLIC HEALTH OR WELFARE OR THE ENVIRONMENT.