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THE REMEDIAL ACTION ALTERNATIVES DEVELOPED IN THE FEASIBILITY STUDY FOR OPERABLE UNIT NO. TWO <br />FOR THE CLEAR CREEK/CENTRAL CITY SITE ARE: <br />NO ACTION <br />SLOPE STABILIZATION AND RUNON CONTROL <br />CAPPING <br />OFF-SITE DISPOSAL <br />CHEMICAL FIXATION <br />REPROCESSING. <br />ALTERNATIVES WERE SUBJECTED TO AN INITIAL SCREENING TO NARROW THE LIST OF POTENTIAL REMEDIAL <br />ACTIONS FOR FURTHER DETAILED ANALYSES USING THE CRITERIA OF COST, EFFECTIVENESS, AND <br />IMPLEMENTABILITY (ACCEPTABLE ENGINEERING PRACTICES) AS DIRECTED BY 40 CFR SECTION 300.68(G). A <br />DESCRIPTION OF EACH ALTERNATIVE FOLLOWS ALONG WITH THE RESULTS OF THE INITIAL SCREENING <br />ANALYSIS. <br />NO ACTION ALTERNATIVE <br />UNDER THE NO ACTION ALTERNATIVE, THERE WOULD BE NO MONITORING ACTIVITIES AND NO NEW BARRIERS <br />WOULD BE CONSTRUCTED TO RESTRICT ACCESS TO THE TAILINGS AND WASTE ROCK PILES. THE ANALYSIS OF <br />THE NO ACTION ALTERNATIVE ANALYSIS WAS SUMMARIZED EARLIER IN THIS DOCUMENT IN THE SECTION <br />ENTITLED "CURRENT SITE STATUS". THE EVALUATION INDICATED THAT POTENTIAL HUMAN HEALTH AND <br />ENVIRONMENTAL IMPACT COULD RESULT FROM THE TAILINGS AND WASTE ROCK PILES. IN PARTICULAR, <br />CATASTROPHIC FAILURE AND RUNOFF COULD AFFECT AQUATIC LIFE AND DOWNSTREAM WATER USERS. IN <br />ADDITION, INGESTION OF TAILINGS OR WASTE ROCK MAY HAVE SOME EFFECTS ON HUMAN HEALTH UNDER THE <br />FUTURE RESIDENTIAL USE SCENARIO. THE NO ACTION ALTERNATIVE SERVES AS A BASELINE AND WAS <br />RETAINED FOR FURTHER ANALYSIS AND CONSIDERATION AS REQUIRED BY SECTION 300.68(F)(1)(V) OF THE <br />NCP. <br />SLOPE STABILIZATION AND RUNON CONTROL ALTERNATIVE <br />WPE STABILIZATION MEASURES ELIMINATE OR REDUCE CONTAMINATION OF SURFACE WATER RESULTING FROM <br />COLLAPSE OF TAILINGS AND WASTE ROCK PILES INTO THE STREAM. SLOPE STABILIZATION MEASURES CAN <br />INCLUDE EXCAVATION, GROUTING AND CONSTRUCTION OF RETAINING WALLS. IN ADDITION, CONTAMINATION OF <br />SURFACE WATER RESULTING FROM SHEET FLOW OVER THE PILES CAN BE REDUCED BY PROVIDING RUNON CONTROL <br />TO THE PILES. RUNON CONTROL CAN INCLUDE DIVERSION DITCHES AROUND THE PILES OR CULVERTS THROUGH <br />THE PILES. <br />INITIAL ASSESSMENTS INDICATED THAT SLOPE STABILIZATION AND RUNON CONTROLS ARE EFFECTIVE AND CAN <br />BE IMPLEMENTED. THEREFORE, THESE ALTERNATIVES WERE CONSIDERED FURTHER IN THE DETAILED SCREENING <br />OF REMEDIAL ACTION ALTERNATIVES. THE INITIAL SCREENING OF STABILIZATION ALTERNATIVES IDENTIFIED <br />THE FOLLOWING ALTERNATIVES BY SITE FOR FURTHER STUDY: <br />GREGORY INCLINE <br />- CONCRETE CRIB WALL <br />- TIMBER CRIB WALL <br />- BOX CULVERT <br />- RUNON CONTROL. <br />BIG FIVE <br />- EXCAVATION AND SLOPE LAYBACK <br />- EROSION PROTECTION AT TOE <br />- RUNON CONTROL. <br />NATIONAL, ARGO, AND QUARTZ HILL <br />0 - RUNON CONTROL. <br />THE INITIAL SCREENING EVALUATION INDICATED THAT GROUTING AND RETAINING WALLS AT THE BIG FIVE <br />WERE NOT TECHNICALLY FEASIBLE. THESE ALTERNATIVES WERE ELIMINATED AND NOT CONSIDERED IN THE <br />DETAILED SCREENING.