p 1182806-R8 SDMS
0 STATE OF COLORADO D Record of Decision ^ for the Idarado Mining and Milling Complex
D March 17, 1987 n SUPERFUKJ J fl.!nCOPD CaitS RECORD OF DECISION REMEDIAL ALTERNATIVE SELECTION
SITE: Idarado Mine facility; San Miguel, Ouray and San Juan Counties, Colorado. DOCUMENTS CONSIDERED:
I have considered all significant matters raised in the documents listed in the index to the Public Record in making my decision of the most cost-effective remedial alternatives for the Idarado Mine facility in San Miguel, Ouray and San Juan Counties, Colorado. In addition, I have considered relevant and appropriate portions of depositions taken and documents produced in the case of State of Colorado v. Idarado Mining Co., et al. v. Baumgartner Oil Co., et al.. Civil Action 83-C-2385. I have discussed the foregoing documents with the technical staffs of: the Department of Health, Department of Natural Resources, and the State's consultants, and have considered their recommendations. DESCRIPTION OF SELECTED REMEDY; Remedial Actions Telluride Valley TAILINGS. Tailings and waste materials will be con solidated onto tailings piles #5 and 6 and tailings will be consolidated into a disposal area near Society Turn. Runon diversion structures, flood control features and erosion resistant multilayer caps will be constructed on tailings piles #5 and 6 and at the Soc iety Tum disposal area. WASTE PILES. Runon will be diverted around the meldrum and mill level waste piles. SOILS. Soils in the Town of Telluride and adjacent areas with lead levels in excess of 500 ppm will be removed, covered, mixed, sodded or treated in coop eration with the Town of Telluride. Public health monitoring programs will be conducted in the Town of Telluride. D MILL SITE WASTE. Confirmation studies will be conducted to determine that polychlorinated biphynels (PCB's) and other organic wastes have been cleaned up according to RCRA and TSCA regulatrons. Mill site soils with lead levels in excess of 1000 ppm will be removed, treated, or covered. MINE PORTAL DISCHARGES. A passive geochemical water treatment system will be constructed to treat up to 8900 gallons per minute of mine drainage from the meldrinn and mill level tunnels. An active treatment system or an equally effective system will be implemented if the D passive system is ineffective in achieving cleanup stand- [—I ards for the San Miguel River. Mine water above the 1200 M mine level will be diverted to the Treasury Tunnel in the Red Mountain Creek Valley. SAN MIGUEL RIVER. Habitat enhancement measures will be -1 undertaken along the San Miguel River in the Telluride valley. Restocking of fish in San Miguel River will be C undertaken.
[—] High Country TAILINGS AND WASTE PILES. Surface runon will be diverted „ around waste piles and waste material will be removed from stream courses or stream courses will be rechanneled. MINE PORTALS. Selected portals will be plugged. J MINE INFLOW CONTROL. Water will be diverted away from collapse features and other areas that allow inflow to [—] the mine. L.. ^ Red Mountain Valley -^ TAILINGS PILES. Tailings will be consolidated into one site (Tailings pile #A) in the Red Mountain Creek Valley. n Runon Diversion structures, flood control features and U erosion resistant multilayer caps will be constructed on tailings pile #4 n [j WASTE PILES. Surface runon will be diverted around waste piles. Waste material will be removed from stream courses n or stream course will be rechanneled. MILL SITE WASTE. Confirmation studies will be conducted to determine that PCB's and other organic wastes have C been cleaned up according to RCRA and TSCA regulations. U Mill site soils with lead levels in excess of 1000 ppm will be removed, covered or treated. -2- MINE PORTAL DISCHARGES. Mine water above the 1200 level will be discharged to Red Mountain Creek to partially neutralize the pH of the creek. Lime stone will be added to Red Mountain Creek to neutra lize the pH. A reservoir will be constructed to accumulate metals precipitated by adding the Treasury Tunnel water and limestone to Red Mountain Creek. D Monitoring and Oversight The surface water, groundwater, soils and aquatic life at the site will be monitored on a regular basis. The State shall designate a site coordinator to oversee all actions required by the record of decision. • DECLARATIONS: Consistent with the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended by the Superfund Amendments and Reauthorization Act of 1986 (CERCLA) and the National Contingency Plan (40 C.F.R. Part 300), I have determined that the remedy selected (as described above and as detailed in the remedial action plan, section 3.0), is a cost-effective remedy that effectively mitigates and minimizes D threats to and provides adequate protection of public health and welfare and the environment, and I have preferred remedial actions in which treatment permanently and significantly reduces Q the volume, toxicity or mobility of the hazardous substances, pollutants, and contaminants over remedial actions not involving such treatment.
Date /A Q n U n TABLE OF CONTENTS u n 1.0 SITE DESCRIPTION Paqe ~] 1.1 Site Background Information 1 J 1.2 History 2 1.3 Physiography and hydrogeology 5 r-i 1.4 Nature and Extent of Problem 6 2.0 REMEDIAL INVESTIGATION/FEASIBILITY STUDY PROCESS 12 3.0 REMEDIAL ACTION PLAN - IDARADO MINING AND MILLING 18 D COMPLEX n 3.1 Purpose and Scope 18 LI 3.2 Site Description 20 3.3 Telluride Valley Remedial Activities 21 J 3.3.1 Tailings Piles 21 3.3.1.1 Remedial Activities 21 r 3.3.1.2 Design Investigations 23 U 3.3.1.3 Remedial Design Criteria 24 n 3.3.2 Waste Piles 26 3.3.2.1 Remedial Activities 26 r-j 3.3.2.2 Design Investigations 27 3.3.2.3 Remedial Design Criteria 27 3.3.3 Soils 27 U 3.3.3.1 Remedial Activities 27 3.3.3.2 Design Investigations 29 C 3.3.3.3 Remedial Design Criteria 30 LJ 3.3.4 Telluride Valley Millsite Waste 31 3.3.4.1 Remedial Activities 31 3.3.4.2 Design Investigations 31 3.3.4.3 Remedial Design Criteria 32 3.3.5 Mine Portals 32 3.3.5.1 Remedial Activities 32 3.3.5.2 Design Investigations 34 3.3.5.3 Remedial Design Criteria 35 U n 3.3.6 San Miguel River Aquatic Life and Hydrologic System 35 3.3.6.1 Remedial Activities 35 3.3.6.2 Design Investigations 36 3.3.6.3 Remedial Design Criteria 37 3.4 High Country Remedial Activities 37 3.4.1 Tailings and Waste Piles 37 0 3.4.1.1 Remedial Activities 37 3.4.1.2 Design Investigations 38 3.4.1.3 Remedial Design Criteria 39 U 3.4.2 Mine Portals 40 "1 3.4.2.1 Remedial Activities 40 J 3.4.2.2 Design Investigations 40 3.4.2.3 Remedial Design Criteria 41 y 3.4.3 Mine Inflow Control 41 3.4.3.1 Remedial Activities 41 3.4.3.2 Design Investigations 42 U 3.4.3.3 Remedial Design Criteria 42 n 3.5 Red Mountain Remedial Activities 43 3.5.1 Tailings Piles 43 3.5.1.1 Remedial Activities 43 3.5.1.2 Design Investigations 44 3.5.1.3 Remedial Design Criteria 45 -J 3.5.2 Waste Piles 47 n 3.5.2.1 Remedial Activities 47 U 3.5.2.2 Design Investigations 47 3.5.2.2 Remedial Design Criteria 48 n Ij 3.5.3 3.5.3.Red Mountai1 Remedian Creel kActivitie Millsites Wastes 48 n 3.5.3.2 Design Investigations 48 U 3.5.3.3 Remedial Design Criteria 49 3.5.4 Mine Portals 50 -2- 3.5.4.1 Remedial Activities 50 3.5.4.2 Design Investigations 51 3.5.4.3 Remedial Design Criteria 51 3,5.5 Red Mountain Creek and the Uncompahgre River Aquatic Life and Hydrologic Systems 53 3.5.5.1 Remedial Activities 53 3.6 Remedial Action Schedule and Milestones 53 3.7 Performance Plan 54 D 3.7.1 Introduction 54 3.7.2 Scope of the Performance Plan 55 3.7.3 Contents of Performance Plan 55 3.7.3.1 Organizational Structure 56 3.7.3.2 Surveys, Inspection, Sampling and Testing 57 3.7.3.3 Changes and Corrective Actions 58 3.7.3.4 Documentation Requirements 58 3.7.4 Compliance Monitoring Activities 59 3.7.4.1 Surface Water Monitoring 59 D 3.7.4.2 Ground Water Monitoring 61 3.7.4.3 Aquatic Life Monitoring 65 3.7.4.4 Air Quality 66 3.7.4.5 Soil Testing Program 67 3.7.4.6 Revegetation 68 3.7.4.7 Construction Monitoring 68 3.7.4.8 Water Rights 69 3.8 Compliance Framework 69 U 3.9 Public Health Assessment Program 71 n u 3.9.1 Health Effects 71 4.0 IMPLEMENTATION SCHEDULE AND COMPLIANCE STANDARDS 72 4.1 Implementation Milestones 72 4.2 Compliance Standards 73 -3- 4.2.1 Soils 78 4.2.1.1 Populated Soils 78 4.2.1.2 Unpopulated Soils 79 4.2.1.3 Soils cleanup methodology 79 4.2.2 Surface Water 80 4.2.2.1 San Miguel River 80 4.2.2.2 Uncompahgre River and Red Mountain Creek 83 4.2.2.3 Point Source Discharges 85 D 4.2.2.4 Antidegredation and basic standards 86 4.2.3 Ground Water 88 4.2.4 Vegetation 90 5.0 SELECTION RATIONALE 92 u 5.1 Tailings 94 5.1.1 Selected Option 94 5.1.2 Rejected Options 94 n 5.1.3 Selection Rationale 95 u 5.2 Waste Rock 99 5.2.1 Selected Option 99 5.2.2 Rejected Options 99 5.2.3 Selection Rationale 99 5.3 Mine Water Drainage 101 5.3.1 Selected Option 101 D 5.3.2 Rejected Options 101 5.3.3 Selection Rationale 102 5.4 Hydrologic Systems 103 5.4.1 Selected Option 103 -4- 5.4.2 Rejected Options 103 5.4.3 Selection Rationale 104 5.5 Soils 105 5.5.1 Selected Option 105 5.5.2 Rejected Options 106 5.5.3 Selection Rationale 106 5.6 Millsite Cleanup 107 5.6.1 Selected Option 107 5.6.2 Rejected Options 108 5.6.3 Selection Rationale 108 5.7 Telluride Valley 108 5.8 High Country 109 5.9 Red Mountain Creek and Uncompahgre Valleys 109 5.10 Effectiveness of the Red Mountain District Remedial Actions 109 5.11 Effectiveness of the Telluride 0 District Remedial Actions 113 n 6.0 COMMUNITY RELATIONS ACTIVITIES 121 6.1 The Remedial Investigation/Feasibility Study Process 121 6.1.1 General (Entire Site) 124 U 6.1.2 Telluride District 1476 6.1.3 Red Mountain District 153 6.2 The Record of Decision Process 158 n RECORD OF DECISION APPENDIX A AG Alpha No. LW HW HXEO AG File No. CHW8700770/TC -5- n IDARADO RECORD OF DECISION 1.0 SITE DESCRIPTION 1.1 SITE BACKGROUND INFORMATION The Idarado Mining and Milling Complex is located in south western Colorado within San Miguel, Ouray, and San Juan Counties. The complex covers roughly 13 square miles and spans two major • drainages, the San Miguel River, and Red Mountain Creek, a tribu- n tary of the Uncompahgre River. Existing facilities include many LJ miles of underground workings, a large mill and office complex IJ (Pandora Mill) for processing ore located about 1 mile up valley „ from the Town of Telluride, offices with an old mill area at Red ^ Mountain, eleven tailings piles where waste products from milling n are stored, and numerous mine portals and waste rock piles. Two major portals. Mill Level and Meldrum Tunnels, discharge the IJ majority of mine drainage to the San Miguel River. Eleven other P portals discharge into Savage and Marshall Creeks, tributaries to U the San Miguel River. The Treasury Tunnel, Genessee, Guston, C Joker, Larson Brothers, and numerous smaller portals discharge to Red Mountain Creek. n J The complex can be conveniently divided into three major o areas, the Red Mountain Valley, the High Country, and the -1- 0 n Telluride Valley. The Telluride Valley includes the Pandora Mill area, the Meldrum and Mill Level Portals, and six tailings piles that extend downvalley to the Town of Telluride. The High Coun try refers to the high basins north and east of the Telluride n LJ Valley including Savage, Marshall, and Commodore Gulch. These n basins contain numerous mine adits and waste rock piles. The Red Mountain Valley is made up of the Red Mountain Mill area, numer- ous mine adits and five tailings piles that extend from the Red Mountain Mill site downvalley to Ironton Park. u n 1.2 HISTORY p Mining of the area began in about 1874 with hundreds of mining claims owned by many parties. Idarado Mining Company n became active in the area in 1939. By 1956 Idarado had acquired and consolidated most of their present holdings. Mining for (j zinc, copper, lead, silver, and gold together with milling of r-| these metals continued until 1978 at which time active mining and milling ceased. The property has been maintained on a standby 0 basis since that time. Numerous incidents of surface water pollution and blowing tailings have been reported from the Idarado site. In 1963, the State of Colorado, Department of Health, advised Idarado that effluent discharging from the mill and tailings piles contained 1 quantities of lead, arsenic, cyanide, and copper above tolerable J -2- n ii limits for drinking water. Telluride citizens voiced their con cerns about blowing tailings and leaching of metals from the site n in 1966. During the late 1970's and early 1980's the Town of Telluride continued to express concerns about blowing tailings. The town was also concerned about ground water contamination by chromium discovered during the testing of two new wells con structed for the Town's water supply. The source of the chromium was tailings pile No. 6 where waste (tailings) from the Pandora Mill was disposed. On October 29, 1976, a National Pollution Discharge Elimi nation System (NPDES) Permit was issued to Idarado by the Colo rado Department of Health. Numerous spills and other unauthor ized discharges have occurred at the Idarado complex during the 1970's and 1980's. In December 1983, the State of Colorado filed a lawsuit for natural resource damages and response costs against Idarado Mining Company, Newmont Services Ltd., and Newmont Mining Corpo ration (hereinafter collectively referred to as "Idarado") pur D suant to the Comprehensive Environmental Response, Compensation n u and Liability Act (CERCLA), 42 U.S.C. sec. 9601-9657 (1980), as subsequently amended by the Superfund Amendments and n Ij Reauthorization Act, Pub. L. No. 99-499, 100 Stat. 1613 (1986) (SARA) (hereafter the Act, as amended, shall be referred to as U -3- n U I "CERCLA"). During 1985, the site and surrounding areas were investi- j gated by the state's consultants in order to define the nature Pl and extent of contamination. ^ The investigation resulted in the publication of two P reports by the State of Colorado. The first report, entitled "Idarado Mining and Milling Complex Remedial Investigation," U April 1986, identified the nature and extent of the site problems p and provided a framework for designing remedial measures. The second report,"Idarado Mining and Milling Complex Feasibility n Study," identified a range of remedial alternatives that could be undertaken at the site and evaluated their cost and effective- [j ness. Both reports were issued for public comments and the State Pl of Colorado held public meetings to receive oral comments from ^ the public after issuance of both documents. n Consistent with the National Contingency Plan, 40 C.F.R. sec. 300 (1985) (NCP) and CERCLA section 117, 42 U.S.C. sec. I— [J 9617 (1986), and based on the nature and extent of contamination [~j at the Idarado facility, as defined by the State's Remedial Investigation, the range of remedial alternatives, and the public n comments, on February 9, 1987, the State of Colorado issued a draft final report, entitled "Preliminary Record of Decision for n \j the Idarado Mining and Milling Complex." The Preliminary Record Pl of Decision presented the state's proposed remedial action plan -4- n n for the Idarado facility. Public comments regarding the Prelimi nary Record of Decision were received by the state. A public n (J meeting was also held to receive oral comments. p Culminating this process the State of Colorado now issues its "Record of Decision for the Idarado Mining and Milling Com- n plex" (ROD) which presents the final remedial action plan for the Idarado facility. 0 r-N 1.3 PHYSIOGRAPHY AND HYDROGEOLOGY The Idarado Mining and Milling Complex is located in the G San Juan Mountains, which are the western most extension of the n southern Rocky Mountain physiographic province in Colorado (Fenneman, 1931). Topography is extremely rugged in the San Juan 1 Mountains and is dominated by sharp peaks, narrow ridges, broad basins, and deep steep-walled canyons resulting from glaciation Z of the area (Fischer and others, 1968; Mather, 1957). Ironton n Park and the San Miguel River Valley are the only relatively broad and flat areas within the site. j' Based upon field observations in the Red Mountain District, r^ the area near the Red Mountain Plant Yard and downstream to Mclntyre Gulch contains sparse amounts of valley fill material that could act as a ground water aquifer. Thus, ground water in this area appears to be directly connected to surface waters. A valley fill aquifer also exists in the area of Ironton Park along -5- Red Mountain Creek. In the Telluride District, previous studies by the United States Geological Survey (Grove, et al., 1979) and the state's remedial investigation has shown that ground water along the San Miguel River is hydrologically connected with surface water from the area of the Pandora Mill site downgradient to the west, past the Town of Telluride. The close association of ground water and surface water in both the upper San Miguel River and the upper Red Mountain Creek make differentiation of these two pathways difficult. U 1.4 NATURE AND EXTENT OF PROBLEM a. Tailings are the waste product of the milling process which consists of finely ground ore, water, and chemical rea gents. Releases from tailings to the environment occur through surface water and wind erosion and ground water seepage. There are six tailings piles in the Telluride District containing approximately 12 million tons of tailings. The largest of these n U piles lies adjacent to the Telluride Town Park. There are also P miscellaneous tailings along the San Miguel River in the U Telluride Valley, specifically including the three tailings piles n at Society Turn downvalley of Telluride. There are five tailings piles and other miscellaneous tailings in the Red Mountain Dis- U trict containing approximately 2 million tons of tailings. Other -6- n u miscellaneous tailings piles exist in the Telluride Valley, Red Mountain Valley, and in the High Country watersheds. b. Mine drainage refers to surface water that n infiltrates through fractures and mine openings into the under- U ground workings, degrades in quality in some cases due to n increased acidity and metal pick-up and finally discharges to the surface through mine portals. There are a total of 17 mine por tals at the Idarado facility that are known to discharge year round. Numerous other portals exist that show evidence of dis- U charge during spring runoff. The yearly average discharge from n the Mill Level and Meldrum Portals, the two major portals in the Telluride District, is 4.82 million gallons per day. c. Mine waste rock is broken mineralized and unmineralized rock from the underground workings which is low in U ore. Mine waste rock was deposited underground or near the mine n portals. Portal water discharges and other waters leach through the mineralized waste rock resulting in increased metals concen- j trations. Mine waste rock piles exist near the Mill Level and Meldrum Tunnels, near adits in the High Country and adjacent to U numerous portals in the Red Mountain Valley. n The major contaminants from the Idarado facility are heavy metals and metalloids that include: " aluminum (Al) ** iron (Fe) " arsenic (As) *» lead (Pb) -7- n 0 barium (Ba) o manganese (Mn) o cadmium (Cd) o molybdenum (Mo) 0 chromium (Cr) o nickel (Ni) 0 copper (Cu) o silver (Ag) o zinc (Zn) • Cyanide (CN) is also present. In addition to heavy metals contaminants, manmade organic chemicals used in ancillary operations were found illegally dis n posed of or improperly stored near the mill area in the Telluride District. These include PCB's from electrical equipment and sol n vents, primarily 1,1,1 trichloroethane (TCA) and acetone. Natural resource contamination from the Idarado facilities G by ground water, surface water and air transport pathways has been documented in the state's Remedial Investigation Report. Concern with Idarado's facilities came to the forefront in 1978 when the Town of Telluride completed two new municipal water supply wells to supplement the town's drinking water supply. The wells were contaminated with hexavalent chromium (Cr{VI}) which was seeping from the tailings piles. Ground water quality has improved since mill shutdown in 1978 and water from the city wells now meets primary drinking water standards. Idarado has made an alternate water supply available to Telluride since 1978 to supplement the town's other sources of water. In order to accommodate the town's future growth, Telluride has prepared -8- 0 n engineering plans for a new surface water treatment facility. Dust blowing from Idarado's tailings piles has been a major ' problem to the citizens of Telluride. The first complaints of blowing tailings to the Colorado Department of Health, Air Pollu- U tion Control Division were made in 1975. Concern over windblown n tailings precipitated two studies in the late 1970's by the Colo- u rado Department of Health, and the United States Public Health 1] Service, Centers for Disease Control. Degradation of surface water quality and aquatic life habi- ^ tat in the San Miguel River and Red Mountain Creek has been Cl addressed by state agencies as early as 1963. Sources of contam ination of surface waters from the Idarado facility include acid (J mine drainage, tailings spills, seepage from disposal facilities, n and erosion of tailings. Idarado's NPDES permit, issued by the Colorado Department of Health on October 29, 1976, addressed four discharge points; 001, the outfall of mine drainage from the Mill Level Tunnel; 002, the outfall of mine drainage from the Treasury Tunnel; 003, the outfall of mine drainage from the Meldrum Tunnel; and 004, the outfall of the decant line from tailings pile No. 6. Under the permit, limitations for cadmium, copper, lead, mercury, zinc, cyanide, oil and grease, pH, and total sus pended solids were applicable to surface water discharges leaving the site. Idarado has constructed perforated pipelines (weep lines) at the Meldrum and Treasury Tunnel portals in order to -9- allow infiltration of the discharges from these portals into soils and ground water adjacent to the San Miguel River and Red Mountain Creek. Lagoons were also constructed at the Mill Level Tunnel, the tailings pile No. 6 decant line and below the Treas- n J ury Tunnel weep line to contain surface flows and preclude dis- p charges to surface water streams. The weep lines and lagoons promote releases of mine water and mill tailings water to soils j and ground water. The permit, however, only addresses direct discharges to surface waters. Ll The Idarado mine has had a history of "bypasses" from the r~) infiltration lagoons that receive mine drainage from the Mill Level Tunnel. A bypass can be described as a discharge of efflu ll ent that does not meet limitations or stream standards but is LJ allowed under unusual circumstances. Bypasses from the lagoons Ll occurred in 1983, 1984, and 1985, during which time additional -| lagoons were added to the system. In all cases where bypasses from the infiltration lagoons were claimed, a discharge to sur- I face waters via overtopping of the lagoons was about to occur. The lagoons have thus been ineffective in containing high flows U from the Mill Level portal in 3 of the last 8 years. r-i The infiltration lagoons are also ineffective in treating low flows. Data and analysis presented in the state's Remedial I Investigation and in the report on "Surface and Ground Water Hy drology at the Idarado Mine Site Telluride/Ouray, Colorado" U—J -10- (Water, Waste and Land, 1986), prepared for the defendants' coun sel by Water, Waste, and Land, Inc., indicate that the Mill Level n Tunnel lagoons as well as the Meldrum Tunnel Portal are signifi n cant contributors of cadmium, copper, iron, and zinc to instream u loads observed in the San Miguel River via ground water. n Some documented violations of the NPDES permit are summa u rized in the state's Feasibility Study. Unpermitted discharges 1 of tailings directly into surface waters were observed as recently as April, May and July 1985, by the state's consultants U and personnel from the State Department of Health. These n observed discharges included tailings transported into both Red Mountain Creek and the San Miguel River through breaches in tail- / ings dams caused by snowmelt runoff, large seeps issuing from dam toes with subsequent flow into Red Mountain Creek, and an over- LJ flow decant line that carried impounded tailings water into Red n Mountain Creek. During site investigations conducted in Septem ber 1985, twelve unpermitted mine portal and shaft discharges ri I were also observed in Savage, Marshall, and Commodore Gulch basins. LJ Red Mountain Creek is nearly devoid of all desirable forms n of life. The Uncompahgre River is impacted for at least 15 miles downstream of its confluence with Red Mountain Creek. The n u Ridgway Dam Project, a major dam and reservoir with large recrea r-1 tional potential, will be impacted by metal loadings from Red -11- UJ J Mountain Creek. In addition to metal contaminants, organic hazardous sub- I stances, primarily PCB's (polychlorinated biphenyls), 1,1,1 trichloroethane, and acetone were discovered onsite near the L Pandora Mill near Telluride. These were stored and/or disposed p of outdoors in corroded and broken containers that had leaked and contaminated onsite soils (PCB concentrations around certain electrical transformers exceeded 2000 ppm). A total of thirteen electrical transformers and over 200 fifty-five gallon drums were discovered in September 1985. Some of these were inventoried, placed in new drums, and shipped to a RCRA facility in January u 1986. Confirmation studies are needed to verify that these decontamination procedures were complete and effective. 2.0 REMEDIAL INVESTIGATION/FEASIBILITY STUDY PROCESS 0 In December 1983, the State of Colorado filed a lawsuit for natural resource damages and response costs against Idarado Mining Company, Newmont Services, Ltd., and Newmont Mining Corpo D ration pursuant to CERCLA, 42 U.S.C. 9601-9657 (1980) (amended n 1986). u To guide State and Federal agencies in following the responsibilities and response powers created under CERCLA, the United States Environmental Protection Agency established the u -12- National Contingency Plan (NCP) to act as a road map for perform ing clean up activities at a site where releases of hazardous substances are occurring. u The NCP calls for the preparation of a Remedial Investiga- n L tion to determine the nature and extent of the threat presented n by releases from the site. The preparation of a Feasibility Study is also needed in order to present and evaluate proposed a remedies. Five categories of remedial alternatives were evalu n ated for the Idarado facility. These are outlined below: C a. Alternatives for treatment or disposal at an off-site r] facility approved by USEPA (for example under the following acts. Resource Conservation and Recovery Act (RCRA), Toxic Substance Z Control Act (TSCA), Clean Water Act (CWA), Clean Air Act (CAA), and Solid Waste Disposal Act (SWDA) approved facilities), as n U appropriate; n b. As appropriate, alternatives which exceed applicable and relevant public health and environmental standards; c. Alternatives which attain applicable and relevant public health and environmental standards; U d. Alternatives which do not attain applicable or rele- n vant public health or environmental standards but will reduce the likelihood of present or future threat from hazardous substances; j and e. A no-action alternative. -13- n J n u -] A plan for Community Relations and opportunity for public comment on the Remedial Investigation and Feasibility Study is I I also called for under the NCP process. Finally, the Record of Decision (ROD) presents the appro- [J priate remedial action to be undertaken at a site. fj In order to determine the nature and extent of releases from the Idarado site, the State of Colorado undertook both Ln literature reviews and field investigations of the Idarado site. The literature review, including litigation document production, C culminated in the preparation of a report entitled "Preliminary Report - Idarado Mining and Milling Complex" in July, 1985. Field investigations were undertaken by the state during the n spring, summer and fall of 1985 in order to define the level and extent of contamination from the facility during that time period and to gather information for preliminary remedial design. Information gathered by the defendants was also added to the state's data base. This information is summarized in a report entitled "Idarado Mining and Milling Complex — Remedial Investi gation," April 1986. ,i~^ U Prior to and during the Remedial Investigation, the state n established cleanup goals and corresponding objectives to be used in guiding the feasibility study and subsequent selection of a n L site remedy. The goals of the alternatives for the cleanup of the -14- a n u n, Idarado site are: 1) to eliminate or minimize offsite migration of hazardous contaminants; 2) to eliminate or minimize levels of contaminants that have already migrated offsite; 3) to restore U the injured natural resources; and 4) to prevent or minimize n C future harm to the environment and to human health and welfare. [~1 In order to achieve these goals, specific site problems (source components) must be remedied to the fullest extent achievable, n • I Based on the site problems described in the Remedial Inves tigation and the goals outlined previously, the following cleanup U objectives were established for the site. C~] a. Remove or reduce all releases of metals to surface u L! waterswaste ,roc grounk piled swater ands minaned portalsstream ;sediment s from tailings piles. b. Remove or reduce the risk of structural failure of U tailings piles from flooding; n c. Stop or reduce releases of blowing tailings; d. Remove or reduce metals concentrations in soils and j vegetation adjacent to tailings piles and in the Town of Telluride; n- U e. Reduce metals concentrations to levels which protect R macroinvertebrate and fish populations by controlling sources of L metals; f. Assure that proper disposal of all onsite waste is completed according to all applicable and relevant and appropri- 0 -15- u D ate state and federal regulations; g. Assure that the ground water resources of the n Telluride Valley are protected for future use; u h. Assure an engineered remedial design that will mini mize long term maintenance and allow access to the site. p, Based upon the information obtained and the sources and pathways of releases found, the st:ate prepared a study to evalu n L ate various measures to remedy problems at the Idarado site. This study entitled "Idarado Mining and Milling Complex - Feasi bility Study," June 1986 proposed and evaluated six alternative remedial actions for the Idarado site. The Feasibility Study evaluated numerous response actions and technologies for each problem area or component of the site. The evaluation was based on technical criteria, environmental criteria, institutional requirements, public health and cost as outlined in "Guidance on Feasibility Studies under CERCLA" (USEPA, 1985). Public meetings were held in the towns of Telluride and 0 Ouray on July 28 and 29, and October 14 and 15, 1986 to receive public comments on the Remedial Investigation and the Feasibility Study respectively. A public meeting was held in Telluride on n March 2, 1987 and a telephone conference with public officials and interested citizens of Ouray occurred on March 9, 1987 to receive public comments on the Preliminary Record of Decision. Written public comments were also received. Section 6 of this -16- D n document summarizes all comments received regarding the Idarado LJ site during the previous public comment periods. This Record of Decision presents the remedial actions to be n undertaken at the Idarado site based upon the Remedial Investiga u tion, Feasibility Study, Preliminary ROD and public comments cn received. The Remedial Action Plan outlined in section 3.0 of the ROD is also based on the requirements of CERCLA section 121, 42 n U.S.C. sec. 9621 (1986). Section 121 specifically requires reme dial actions which permanently and significantly reduce the volume, toxicity or mobility of contaminants. In assessing the effectiveness of remedial actions section 121 lists the following elements to be considered: (A) the long-term uncertainties associated n with land disposal; (B) the goals, objectives, and requirements n of the Solid Waste Disposal Act; (C) the persistence, toxicity, mobility, and propensity to bioaccumulate of such hazardous substances and their constitu ents; (D) short and long term potential for adverse health effects from human exposure; (E) long term maintenance costs; (F) the potential for future remedial action costs if the alternative remedial action in question were to fail; and -17- (G) the potential threat to human health D and the environment associated with excava tion, transportation, and redisposal, or n containment. L Sections 4 and 5 of the ROD discuss the schedule and com pliance standards and the rationale for the final remedial action selected. n L 3.0 REMEDIAL ACTION PLAN - IDARADO MINING AND MILLING COMPLEX n 3.1 PURPOSE AND SCOPE Past mining, milling and waste disposal practices in the San Miguel River and Red Mountain Creek watersheds have resulted in seepage of contaminated liquids into soils and ground water, L discharge of mine drainage into the San Miguel River, Red Moun- I tain Creek and their tributaries, wind dispersal of tailings material and placement of large quantities of wastes in locations n U which pose a risk to public health and welfare and the environ ment. G The purpose of the Remedial Action Plan (RAP) is to select a cost-effective remedial alternative that effectively mitigates and minimizes threats to and provides adequate protection of L public health and welfare and the environment. This RAP -| describes the activities to be conducted in order to mitigate human health and welfare and environmental impacts from past mining, milling and waste disposal practices. The Remedial -18- n n Action Plan described in this document is based on the Idarado Mining and Milling Complex - Remedial Investigation (RI), the I evaluation of remedial actions in the Idarado Mining and Milling Complex - Feasibility Study (FS), and public comment. These J actions have been determined to be technologically feasible, J reliable, and to provide the greatest protection to the public health, welfare and the environment. The combination of source n j control and control of contaminant migration as described herein has been determined to be cost-effective. n U The remedial activities to be conducted are described in n sections 3.3, 3.4 and 3.5. These activities shall include: 1) u design investigations, 2) remedial design criteria, and 3) reme- n dial actions. Design investigations are needed in order to I u acquire the specific information for final designs and specifica n L tions. Design criteria are those elements which will be used in the preparation of the final designs and specifications. Addi D tionally, the compliance framework is set forth in section 3.8, the performance plan described in section 3.7, compliance dead n lines outlined in section 4.1, and compliance standards in Ll section 4.2. During the design an implementation phases of the n RAP local governments in Telluride and Ouray, as well as San u Miguel and Ouray Counties, will be active participants with the state in developing the necessary mitigation measures to minimize adverse impacts to the communities from the construction -19- U un n projects. L 3.2 SITE DESCRIPTION n The Idarado Mining and Milling Complex is an area covering L approximately 13 square miles located between Telluride and npi Ouray, Colorado, in San Miguel, Ouray and San Juan Counties. n Three major areas have been identified within this site and u include: C a. Telluride Valley: This area is defined by the topo- U n graphic drainage basin of the San Miguel River down to the con- L fluence with the South Fork of the San Miguel River. It contains n six tailings pile Nos. adjacent to the San Miguel River, two u major mine portals (the Meldrum and Mill Level Tunnels), the D Pandora Mill site and two major waste pile Nos. The waste pile Nos. are composed primarily of non-ore-bearing rock removed during tunneling. Also contained in the valley are miscellaneous tailings deposits along the San Miguel River, and contaminated soils, surface water and ground water. r~i b. High Country; The High Country area is defined by the topographic boundaries of Marshall Basin, Savage Basin and Commodore Gulch Basin upstream of Highway 550. It contains dis charging mine adits as well as numerous waste and tailings pile Nos, c. Red Mountain Valley; The Red Mountain Valley area is -20- n n defined by the topographic boundary of the Red Mountain Creek watershed, with the exception of the Commodore Gulch Basin upstream of Highway 550 (which is included in the High Country), downstream to the lower, northeast end of Ironton Park. It con- L tains the Red Mountain mill site, numerous discharging mine por ri tals including the Hero, Hudson, Treasury Tunnel, Guston, Joker, Genessee and Larson Brothers as well as five tailings pile Nos. j that extend from the Red Mountain mill yard downstream to tail ings pile No. 4 in Ironton Park. The Red Mountain Valley area J also contains miscellaneous waste and tailings piles, contami- n nated stream sediments, and surface water. U n 3.3 TELLURIDE VALLEY REMEDIAL ACTIVITIES u 3.3.1 Tailings Piles 3.3.1.1 Remedial Activities The remedial activities for tailings in the Telluride un Valley are intended to minimize and mitigate contaminant releases to surface water, ground water and air, as well as reduce the J potential for future human exposure. Further, these remedial n activities are intended to achieve permanent control of the tail- L ings material. In order to achieve these objectives, the follow ing remedial activities shall be conducted: a. Remove tailings pile Nos. 1-4 and consolidate this -21- n L n u material onto tailings pile Nos. 5 and 6 as the final waste dis posal area. Ln b. Remove miscellaneous tailings from sparsely vegetated and barren areas along the San Miguel River from the Idarado L millsite downstream to Society Turn and consolidate onto tailings J pile Nos. 5 and 6. c. Remove tailings material from the flood plain of the San Miguel River below Society Turn and relocate to a geologically suitable disposal area near Society Turn (Society U Turn disposal area). n d. Construct a multilayered cap from predominantly locally available material with a low permeability layer, an ero n U sion resistant (random fill) layer, and a plant growth media layer, on tailings pile Nos. 5 and 6 and in the Society Turn dis posal area in order to reduce infiltration, minimize surface ero- n sion and eliminate blowing tailings. e. Construct surface water diversion ditches for tail ings pile Nos. 5 and 6, and the Society Turn disposal area to reduce surface water recharge into the tailings and to minimize U long term erosion. J f. Place rip rap along the sides of tailings pile Nos. 5 and 6 and the Society Turn disposal area to eliminate river ero sion of tailings material and to minimize the risk of major or catastrophic failure. D -22- g. Recontour and revegetate all areas disturbed in the construction activities including borrow source and tailings u removal areas. h. Establish a diverse, self-sustaining vegetative cover L on the tailings pile Nos. 5 and 6 cap and the Society Turn dis- [j posal area. i. Implement wind and water erosion control measures during tailings consolidation and cap construction from tailings pile Nos. 5 and 6 and the Society Turn disposal area, and elimi- U nate all liquid discharge to tailings pile Nos. 5 and 6 as soon (—j as final pile configuration is achieved. L 3.3.1.2 Design Investigations C The following design investigations shall be conducted; a. Tailings Material Evaluation: This study shall J include analysis of the location and volume of the material to be (-, moved, and the tailings material characteristics. L^ b. Disposal Site Evaluation: This study shall evaluate ~| tailings pile Nos. 5 and 6 and the Society Turn area and shall include all information necessary to design both disposal facili- n J ties, including pile configuration, cover, and drainage/flood P control features. '-' c. Construction Materials Evaluation: All construction n materials to be utilized in the disposal areas will be investi- -23- D gated as to their location, availability and ability to meet design specifications and remedial design criteria. d. Revegetation Study: A study to determine the proper revegetation techniques on the materials used for cap construc tion shall be conducted. e. Relocation Study: A study shall be undertaken to determine the need and to find places, if necessary, for reloca n tion of the residences in the Pandora and Liberty Bell communi L ties prior to commencement of construction at the tailings piles. n U Results of this study shall be discussed with the Town of n Telluride. I 3.3.1.3 Remedial Design Criteria U n The following design elements and criteria shall be incorporated into the remedial design: LJ a. Soils Cleanup: Soil cleanup beneath tailings pile PI Nos. 1-4 and cleanup of the tailings in the Society Turn area L shall meet the unpopulated soil standards for lead of 1000 mg/kg n (dry weight). b. Tailings Removal: Tailings removal in riparian areas n J along the San Miguel River shall be conducted in those areas where riparian vegetation is sparse or lacking. u c. Tailings Pile Stability: The waste disposal facili u ties (tailings pile Nos. 5 and 6 and the Society Turn disposal -24- Q -] area shall be designed to withstand the forces of a maximum cred ible earthquake and Probable Maximum Precipitation (PMP) or Prob- n able Maximum Flood (PMF) event. d. Flood Protection and Drainage Control Structures: J These structures shall be designed to withstand and convey the p PMP or PMF. e. Infiltration Control: . The multilayer caps for tail n ings pile Nos. 5 and 6 and the Society Turn disposal area shall I I 1 I be designed with a low permeability layer two (2) feet thick with C L a permeability less than 1.0 X 10(-7) cm/sec, an erosion resis- p tant (random fill) layer of two (2) feet in thickness, and a plant growth media layer of two (2) feet in thickness. 1 f. Runoff Control: Side slopes shall be designed with berms, terraces or other means of adequately reducing surface J runoff velocities and controlling cap erosion. g. Society Turn Disposal Area Liner: The liner for the D Society Turn disposal area shall be designed with a permeability n less than 1.0 X 10(-7) cm/sec. h. Vegetation and Revegetation: Self-sustaining vegeta- n U tion shall be established that is capable of self-regeneration p without continued dependence on irrigation, soil amendments or fertilizer, with a vegetative cover density equal to the refer ence area and other requirements of section 4.2.4 to enhance evapotranspi rat ion. D -25- ^ i. Air Emissions: Air emissions from the site shall '-' comply with the Colorado Air Quality Control Act and regulations J promulgated thereunder as discussed in section 4.2. LJ j. Construction Specifications: The remedial design must describe all construction specifications for the disposal (_, facilities including but not limited to materials selection, ^ placement and compaction, provisions for reducing or eliminating n airborne emissions during all construction activities, and maximizing compaction and consolidation of the tailings material. J k. Construction Schedule: The final plans and speci- P fications shall include a schedule and sequencing of all con- LJ struction activities. 3,3,2 Waste Piles 3,3,2.1 Remedial Activities I The remedial activities for the waste piles in the Telluride Valley (primarily Meldrum and Mill Level piles) are P U intended to minimize metals loadings to the hydrologic system and p to preserve the historical values of the waste pile areas. In order to achieve these objectives the following remedial activity shall be conducted: P a. Divert run-on and provide positive drainage away from the waste pile Nos. n -26- 3,3,2,2 Design Investigations n The following design investigations shall be conducted: Z a. Waste Pile Evaluation: This study shall include map- p ping of the waste deposits in the Telluride Valley area and iden- J tification of all historic structures. This information shall be n used in the design of all drainage diversion structures. n 3.3.2.3 Remedial Design Criteria U The following design criteria shall be incorporated into p the remedial design to be approved by the state: a. Drainage Diversion: All drainage (run-on) diversion [ structures shall be designed to convey the 100 year flood event. U 3.3.3 Soils (J 3.3.3.1 Remedial Activities Remedial activities for soils in the Telluride Valley "-' includes populated and unpopulated areas. Soil remedial activi- n ties are intended to assure that- contaminant levels do not threaten human health and that secondary releases of contaminants p L will not occur in the short or long term. Specifically, remedial „ activities for soils in populated areas are intended to reduce LJ human exposure to contaminants found in the Town of Telluride, ~] assure that a permanent solution to these problems is implemented -27- and establish a mechanism to handle future problems. Remedial activities for soils in unpopulated areas are intended to reduce plant and wildlife exposures to contaminants. Local government officials in the Town of Telluride are an integral participant in the planning, design and implementation of remedial measures for soils cleanup in Telluride. The Town of Telluride will be an active partner in all aspects of these remedial activities. The following remedial activities shall be implemented: a. A comprehensive soil testing program shall be devel oped and performed as described in section 3.7.4.5, to further characterize the levels of selected metals throughout the Town of Telluride, especially for properties in areas where the state's consultants have found levels of lead which are above 500 mg/kg. Future growth areas shall be tested in the same manner as devel opment occurs. b. A program for implementation of the soils cleanup Q shall be developed in cooperation with the Town of Telluride. n This program shall address: 1. Cleanup of soils in populated areas; p 2. Cleanup of soils in unpopulated areas. c. Soils in the Town of Telluride and in residential • areas near the Town of Telluride shall be removed, covered, sodded, mixed, treated or addressed through institutional con trols depending upon the potential human health effects of the -28- nu concentration and toxicity of the hazardous substances through n U available pathways of exposure. Removed soils shall be placed in p tailings pile Nos. 5 and 6. The soil clean up levels and method ologies that are presented in section 4.2.1 shall be considered n I in developing the cleanup program. n d. Soils in future growth areas outside the Town of U Telluride shall be tested and then removed, treated, or mixed n depending upon the potential environmental effect of the concen- U tration, mobility, and toxicity of the hazardous substances. j Soils cleanup levels and methodologies are presented in section n U e. Soils in steep or well-vegetated terrain in p unpopulated areas may not need to be removed, covered, treated or mixed depending upon the environmental sensitivity of these U areas. f. Soils cleanup methodology shall follow the criteria Z set forth in section 4,2.1,3, 0 3,3,3,2 Design Investigations The following design investigations shall be conducted: G a. Soils Study: A comprehensive soils sampling program shall be conducted as described in section 3,3,3,1a, Constitu- G -29- n ents to be sampled and the methodologies to be used are described Z in section 3,7,4,5, n b. Future Growth Areas Study: A methodology shall be developed for addressing cleanup of future growth areas. This n J study shall address measures to be undertaken at the time that development occurs, J c. Clean up Methodology Study: Specific technologies to be used for removal, covering, mixing as outlined in section ^-.j 4,2,1.3 shall be evaluated based on site specific conditions in n the Town of Telluride and adjacent areas. Site access, the use of institutional controls (such as deed or zoning restrictions n and controls), and environmentally sensitive areas shall be con sidered in the evaluation, A methodology for field determination of lead concentrations in soils shall be developed, n 3,3,3.3 Remedial Design Criteria The following design elements and measures shall be n incorporated: j-^ a. Residual soil concentrations of lead shall not exceed 500 mg/kg (dry weight) for populated areas and 1000 mg/kg (dry weight) for unpopulated areas, n b. Methodologies used for remedial activities shall be J those described in section 4,2,1, -30- u 3,3,4 Telluride Valley Millsite Waste 3,3,4.1 Remedial Activities LJ Remedial activities at the Millsite are intended to insure P that levels of organics and metals in the soils do not threaten LJ public health and that releases of these contaminants are mini- C mized. Specifically, these activities are intended to reduce long term human exposure to contaminants. The following reme- U dial activities will be required: P a. Confirm with appropriate testing that all hazardous LJ organic substances such as PCB or TCA have been removed and dis- n posed of in an approved TSCA and/or RCRA facility as required by law. L b. Remove all tailings material and soils with lead con- P centrations in excess of 1000 mg/kg (dry weight) to tailings pile •^ Nos. 5 and 6. L c. Revegetate all areas disturbed during construction or removal activities (existing structures may be left in place). n p 3.3.4.2 Design Investigations L n The following design investigation shall be conducted: a. Millsite Soil Survey: This study shall system- J atically sample the Millsite for lead and pH as well as PCB's and P organics in order to determine constituent levels and locations. ^ -31- n UJ n This study will verify previous sampling at the millsite and U determine tailings or soils to be removed. [j 3.3.4.3 Remedial Design Criteria n ^ The following design elements and measures shall be un incorporated; a. Residual soil concentrations of lead shall not exceed U 1000 mg/kg (dry weight) and shall meet all TSCA and/or RCRA . P requirements as required by law for PCB's and organics, L-' b. Construction activities shall follow the criteria set n forth in sections 3,7.4,5, 4,2,1, and 4.2,4, y 3,3,5 Mine Portals 3,3.5.1 Remedial Activities n The remedial activities for discharges from mine portals in LJ the Telluride Valley are intended to minimize the contaminants p being released to the San Miguel River. In order to achieve this objective, the following remedial activities shall be performed; a. Reduce surface and ground water inflows into the mine workings associated with the Meldrum and Mill Level Tunnels (see n U section 3.4.3, Mine Inflow Control). r^ b. Control, reroute or divert flows within the mine so that Meldrum and Mill Level portal discharges and associated Q metals loads are decreased. n U c. Divert mine water by gravity above the 1200 level of p the mine for discharge from the Treasury Tunnel. d. Where possible segregate mine water which meets water quality standards and discharge directly to the San Miguel River water that meets water quality and effluent limitation standards. U e. Construct and maintain a settling pond and p geochemical absorption field on Royer Gulch to passively treat a mine water flow of no less than 8900 gpm in accordance with the findings of the design investigations (section 3.3.5.2) and the design criteria (section 3.3.5.3). Li f. If five (5) years of ground water and surface water C monitoring indicates that the passive treatment system will not achieve contaminant concentrations listed on Table 4.1 within a reasonable time, or that the ground water standards set forth in section 4.2 are being exceeded, an active treatment plant of ri LJ approximately 700 gpm and other technically feasible alternatives p shall be investigated. The most cost-effective of these alterna tives shall be implemented, if reasonable further progress j j achievedtowards .meetin g the water quality standards in Table 4.1 can be G -33- 3.3.5.2 Design Investigations P The following design investigations shall be conducted: U a. Mine Inflow Study: See section 3.4.3.2, Mine Inflow n u Control. b. Internal Mine Flow Study: This study shall identify all internal mine flows and evaluate measures to control, reroute or divert these flows so that metals loadings are reduced and mine flows are reduced through the use of internal plugging. This study shall also identify "clean water" mine inflows that could be plugged off or diverted and discharged without treat ment. This study shall be performed in conjunction with the Internal Mine Flow Study under section 3.4.3.2. z c. Passive Treatment Systems: Prior to implementation of the remedial measure specified in 3.3.5.I.e., detailed study shall be conducted concerning the location, design and operation of a passive treatment system for a mine portal discharge of 8,900 gpm. This study shall include geochemical tests and an evaluation of the short and long term impacts to surface and n ground waters from the geochemical absorption field. If the study indicates that significant adverse short or long term im G pacts will result from a geochemical absorption field, then an alternative treatment methodology will be designed and imple mented to achieve an equal level of improvement in the water -34- quality of the San Miguel River. 3.3.5.3 Remedial Design Criteria u P The following elements and measures shall be incorporated ^ into the remedial designs: Ci a. Mine Flow and Inflow: All mine inflow and flow U structures shall be designed to withstand the maximum hydraulic U.' head. All mine inflows shall be minimized to the maximum extent P reasonably achievable. b. Water Treatment Systems: All treatment systems shall n be designed to minimize heavy metal loading to the San Miguel River and alluvial ground water and shall meet the effluent pi limitations pursuant to the Water Quality Control Act and ground p water standards in section 4.2.3 and will to the greatest extent ^ practicable achieve surface water standards specified in section n 4.2.2. Discharges from passive treatment systems shall be moni tored according to section 3.7.4.2 (Ground Water Monitoring) and Ll shall meet the requirements of section 3.7.4.8. n 3.3.6 San Miguel River Aquatic Life and Hydrologic System n LJ 3.3.6.1 Remedial Activities P The remedial activities for the San Miguel River hydrologic u system along with the source control measures are intended to 0 G minimize and mitigate ground water, surface water, and stream ! 1 U sediments as sources or conveyors of contaminants. These activi- p ties are further intended to improve aquatic life in the San L Miguel River and to assure that both surface and ground water are protected for future use. The following remedial activities shall be implemented: Z a. Remove tailings material from riparian areas to n enhance aquatic life and habitat and to reduce releases in accordance with section 3,3.1.1. b. Restore and improve aquatic habitat in the San Miguel River to the confluence with the South Fork in order to increase U and protect fish populations and diversity. u 3.3.6.2 Design Investigations The following design investigations shall be conducted: LJ a. Habitat Improvement: Evaluate the existing habitat n in the San Miguel River in order to determine areas in need of improvement and measures to improve those areas. b. Miscellaneous Tailings: Identify locations and volumes of tailings along the San Miguel River according to Ll section 3.3.1.2. 0 n LJ -36- n 3.3.6.3 Remedial Design Criteria The following elements and measures shall be incorporated n ,j into the remedial designs: p a. Habitat Improvement: All habitat improvement mea n sures shall be designed to allow for a stable stream channel at flows up to the 100 year flood. b. Tailings material and mine waste: All tailings and p Ln mine waste in the riparian areas shall be removed in accordance with section 3.3.1.3. All removal methods used shall minimize (t the generation of suspended sediments in the San Miguel River and its tributaries. c. Ground Water Protection: Discharges to ground water n fied in section 4.2.3 and shall not cause violations to the sur np shall not cause violations to the ground water standards speci- face water standards specified in section 4.2.2. 3.4 HIGH COUNTRY REMEDIAL ACTIVITIES n u 3.4.1 Tailings and Waste Piles n 3.4.1.1 Remedial Activities p Remedial activities for the high country tailings and waste pile Nos. are intended to minimize and mitigate contaminant p U releases to surface water, while limiting environmental damage p and preserving the historical values of the area. The following ^ -37- 0 remedial activities shall be conducted: a. Remove tailings and waste material from drainage ways. L b. Reconstruct stream courses where past waste disposal practices have resulted in stream channel alteration. c. Divert surface run-on around the waste pile Nos. n U d. Construct a settling pond at the base of Marshall p Creek to reduce suspended metal loads from Marshall Creek, prior L to discharge to the San Miguel River. n (J 3.4.1.2 Design Investigations p The following design investigations shall be conducted: a. Waste Material Evaluation; The location of all waste and tailings piles shall be mapped. The location of all drainage ways shall also be mapped. The waste piles shall also be assayed LJ for metal content and evaluated for releases to surface waters, p b. Waste Pile Remedial Methodology: This study in con- LJ junction with the Waste Materiai Evaluation shall identify the appropriate measures to divert water around waste piles, recon G struct drainages through waste areas and remove waste material from drainage ways, c. Settling Pond Evaluation; This study shall evaluate the size, design and location of the settling pond at the base of -38- Q Marshall Creek in order to achieve settling of total suspended U solids. R 3,4,1,3 Remedial Design Criteria n The following elements and measures shall be incorporated ri into the remedial design: U a. Drainage Diversion: All (run-on) diversion struc- L tures shall be sized to convey a 100 year flood event. P b. Waste Material Removal: All waste material shall be ^ removed from the 100 year flood plain. The slopes of all n redeposited material shall be reconfigured to assure stability of U the waste materials. L c. Removal Criteria: Where waste material is removed p from the stream, clean up shall be performed until all visible L waste IS removed from the stream. M d. Historic Structures: All measures will be taken to avoid destruction of historic mining structures. P J e. Settling Pond Design: The settling pond shall be p designed to remove suspended solids and zinc loads to the maximum extent reasonably achievable. n -39- G 3.4.2. Mine Portals u n 3.4.2.1 Remedial Activities U Remedial activities for high country mine portals are p intended to reduce metals loading to tributaries of the San "^ Miguel and Uncompahgre Rivers, reduce mine water contact with I waste material, and to reroute contaminated water into the pas- J sive treatment systems. n nU dial activitieIn orders tshalo achievl bee conductedthese objectives: , the following reme a. Plug mine portals with high metals concentrations and where geologic and hydrologic conditions allow. b. Divert mine water around waste piles where discharges continue. p 3.4.2.2 Design Investigations The following design investigations shall be conducted; n a. Mine Portal Evaluations: Evaluate mine portals for discharge, flows and quality and hydraulic heads so that plug designs can be determined. n b. Mine Portal Diversion: This study shall evaluate means of diverting any mine portal discharges that come in con tact with mine waste material. -40- p J Q n •J, 3.4.2.3 Remedial Design Criteria C The following elements and measures shall be incorporated U into the remedial design: D a. Any portal plugs must be able to withstand the maxi- '^n' mum anticipated hydraulic head. n b. Mine water diversions shall be designed to pass the LJ largest reasonably anticipated outflows. p 3.4.3 Mine Inflow Control 3.4.3.1 Remedial Activities -^ Remedial activities for sources of mine inflows in the high p country are intended to reduce the amount of water entering and U rn flowing through the mine and thus, the amount of water requiring passive treatment. These actions will decrease metals concentra tions in Marshall Creek and reduce metals loadings to Red Moun tain Creek and the San Miguel River. In order to achieve these objectives, the following reme dial activities shall be undertaken: a. Divert surface water flowing into collapse features, shafts, stopes and other openings that allow water into the mine U and/or seal collapse features, shafts, stopes and other openings P that allow water into the mine. Li b. Seal stream channels that cross mined out veins where n I n u water flows into the mine using grouting or other methods where practical. P 3.4,3,2 Design Investigations 1 The following design investigation shall be conducted: a. Mine Inflow Study: This study shall include iden- P L tification of all mine inflows and analysis of all topographic, P geologic and hydrologic features that connect the surface and the mine in order to reduce water flowing into the mine. This study G shall also evaluate measures to remediate inflows. J 3.4,3,3 Remedial Design Criteria J The following elements and measures shall be incorporated P into the remedial designs: ^ a. Mine Inflow: All mine inflow structures shall be n designed to withstand the maximum hydraulic head, b. Diversion Structures: All diversion structures shall J be sized to convey the 100 year flood event. P c. Channel Sealing: All portions of channels sealed '-' shall be designed to convey the same volume as the original chan- D n J m -42- n 3.5 RED MOUNTAIN REMEDIAL ACTIVITIES 3.5.1 Tailings Piles 3.5.1.1 Remedial Activities The remedial activities for tailings piles in the Red Moun tain Creek Valley are intended to minimize and mitigate contami LJ nant releases to surface water, ground water and air as well as to reduce the potential for human exposure. Further, these reme dial activities are intended to achieve permanent control of the tailings material. In order to achieve these objectives, the following reme dial activities shall be undertaken: a. Remove the buried tailings pile, tailings pile Nos. 1, 2 and 3 and miscellaneous tailings and consolidate this mate rial onto tailings pile No, 4, b. Construct a multilayered cap from predominantly locally available material with a low permeability layer, an ero G sion resistant (random fill) layer, and a plant growth media layer on tailings pile No, 4 in order to reduce infiltration, minimize surface water erosion and eliminate wind erosion of tailings, c. Construct surface water diversion ditches for tail ings pile No. 4 to reduce surface water recharge into the tail ings and minimize long-term erosion, -43- n d. Place rip rap along the sides of tailings pile No, 4 to eliminate stream erosion of tailings material and to minimize 1 the risk of major or catastrophic failure, e, Recontour and revegetate all areas disturbed by the -I construction activities including borrow source and tailings P removal areas, f. Establish a diverse, self-sustaining vegetative cover J on the tailings pile No, 4 cap, ^ g. Implement wind and water erosion control measures LJ during tailings consolidation and cap construction. u 3,5,1,2 Design Investigations The following design investigations shall be conducted: a. Tailings Material Evaluation: This study shall include analysis of the location and volume of the material to be moved, the tailings' material characteristics, and the moisture content of the tailings, b. Disposal Site Evaluation: This study shall evaluate tailings pile No, 4 disposal area and shall include all informa Q tion necessary to design the disposal facility, including pile configuration cover, and drainage/flood control features, n c. Construction Materials Evaluation: All construction materials to be utilized in the disposal areas will be investi- -44- gated as to their location, availability and if they will meet design specifications and remedial design criteria. This shall include materials excavated from the below grade reservoir. p d. Revegetation Study: A study to determine the proper LJ revegetation techniques on the materials used for cap construc- r tion shall be conducted. L 3.5.1.3 Remedial Design Criteria p p The following elements and measures shall be incorporated n into the remedial design: C a. Soils Cleanup: Soil cleanup beneath the buried tail- n ings pile and tailings pile Nos. 1, 2 and 3, and cleanup of the miscellaneous tailings shall meet the unpopulated soil standard L for lead of 1000 mg/kg (dry weight). b. Tailings Pile Stability: The waste disposal facility U (tailings pile No. 4) shall be designed to withstand the forces J of a maximum credible earthquake and probable maximum precipi tation/flood event. [J c. Flood Protection and Drainage Control Structures: These structures shall be designed to withstand and convey the L PMP or PMF. n d. Infiltration Control: The multilayer cap shall be designed with a low permeability layer two (2) feet thick with a permeability less than 1.0 X 10(-7) cm/sec, a plant growth media _ -45- layer of two (2) feet in thickness, and an erosion resistant (random fill) layer of two feet in thickness. n e. Runoff Control: Side slopes shall be designed with P berms, terraces and other means of adequately reducing surface I 1 runoff velocities and controlling cap erosion. n f. Vegetation and Revegetation: Self-sustaining vegeta tion shall be established that is .capable of self-regeneration J without continued dependence on irrigation, soil amendments or p fertilizer, with a cover density to meet the requirements of section 4.2.4. g. Air Emissions: Air emissions shall meet the require ments of the Colorado Air Quality Control Act and regulations P J promulgated thereunder as discussed in section 4.2. p h. Construction Specifications: The remedial design must describe all construction specifications for the disposal j facility including, but not limited to, materials selection, placement and compaction, provisions for reducing or eliminating J airborne emissions during all construction activities, and p maximizing compaction and consolidation of the tailings material, i. Construction Schedule: The final plans and speci- [ fications shall include a schedule and sequencing of all con struction activities. -46- Q 3,5,2 Waste Piles 3.5.2.1 Remedial Activities The intent of the remedial activities for the Red Mountain u Valley waste piles is to minimize metals loadings to the n hydrologic system and to preserve the historical values of the u waste pile areas. The following remedial activities shall be performed: a. Remove waste material from drainage ways and recon struct stream courses. b. Divert surface runon around waste piles. c. Divert mine portal flows around waste piles. 3.5.2.2 Design Investigations The following design investigations shall be conducted: a. Waste Pile Evaluation: This study shall include G identification and mapping of all waste materials and their rela tionship to drainage ways in the Red Mountain Creek Valley. This p [J information together with the Historic Structure Study shall be „ used in the design of all drainage diversion structures. L b. Historic Structures: This study shall identify all Q historic structures located in the area of the waste piles. -47- 3.5.2.3 Remedial Design Criteria The following elements and measures shall be incorporated LJ into the remedial design: I a. Drainage Diversion: All drainage (run-on) diversion n structures shall be sized to convey the 100 year flood event. LJ b. Waste Material Removal: All waste materiai shall be P removed from the 100 year flood plain. The slopes of all redeposited material shall be reconfigured to assure stability of the waste material. P c. Removal Criteria: Where waste material removal is U required, cleanup shall be performed until all visible waste is P removed from the stream. C 3.5.3 Red Mountain Creek Millsite Wastes 3,5,3,1 Remedial Activities Remedial activities at the mill site are intended to ensure G that levels of organics and metals in the soils do not threaten public health and that releases of these contaminants are mini mized. Specifically, these activities are intended to reduce human exposure to contaminants in the long term. The following remedial activities will be required: a. Confirm with appropriate testing that all hazardous organic substances such as PCB or TCA have been removed and dis- -48- n posed of in an approved RCRA or TSCA facility as required by law. b. Remove all tailings material and soils with lead con- L centrations in excess of 1000 mg/kg (dry weight) and dispose of P these materials in tailings pile No. 4. c. Revegetate all areas disturbed during construction or removal activities (existing structures may be left in place). LJ n 3.5.3.2 Design Investigations LJ n LJ The following design investigation shall be conducted: I" a, Millsite Soil Survey: This study shall system atically sample the Millsite for lead and pH as well as PCB's and P . • J organics in order to determine constituent levels and locations. 3.5.3.3 Remedial Design Criteria U The following design elements and measures shall be p incorporated: a. Residual soil concentrations of lead shall not exceed 1000 mg/kg (dry weight) and shall meet all RCRA and TSCA require ments for PCB's and organics. c J b. Construction activities shall follow the criteria set p forth in sections 3.7.4,5, 4.2,1, and 4,2,4, u -49- G u n 3,5,4 Mine Portals L n 3,5,4,1 Remedial Activities The remedial activities for discharges from mine portals in the Red Mountain Valley are intended to minimize the contaminants released to Red Mountain Creek and the Uncompahgre River. In U order to achieve this objective, the following remedial activi- P ties shall be performed: a. Reduce surface and ground water inflows into the mine J workings associated with discharging portals (see section 3.4.3, Mine Inflow Control). GG b. Divert mine water by gravity above the 1200 level of n the mine to the Treasury Tunnel. c. Discharge the mine water from the Treasury Tunnel to I Red Mountain Cireek in order to induce chemical precipitation of metals. LJ d. Construct and maintain a below grade reservoir in n Ironton Park or other acceptable location to act as a mine water treatment system. Construct and maintain a small sedimentation jj reservoir just upstream to reduce sediment load to the below grade reservoir, LJ e. Charge the stream with limestone above the reservoir n in order to enhance treatment. f. Divert mine water currently discharging from the J Larson Brothers Mine around the existing waste pile and drain any -50- G ponded water in the area. This water shall be channeled to the below grade reservoir. 3.5.4.2 Design Investigations G The following design investigations shall be conducted; a. Mine Inflow Study: This study shall include iden- U tification of all mine inflows and analysis of topographic, p geologic and hydrologic features that connect the surface and the mines of the Red Mountain Creek Watershed in order to reduce water flowing into the mine. This study shall evaluate measures to remediate inflows. n Li b. Reservoir Study: This study shall evaluate the opti- p mal reservoir size, design and location in order to achieve set tling of the precipitate formed by the addition of limestone and diversion of water above the 1200 level to Red Mountain Creek, Q c. Construction Materials Evaluation: All materials used in the construction of the passive treatment system will be investigated as to their location, availability and ability to meet design specifications and remedial design criteria. 3.5.4.3 Remedial Design Criteria The following elements and measures shall be incorporated into the remedial designs: -51- a. Mine Flows and Inflows: All mine flow and inflow prevention structures shall be designed to withstand the maximum L hydraulic head. All mine inflows shall be minimized to the maxi- p mum extent possible. b. Passive Treatment System: The passive treatment sys- ' tem shall be designed to handle the average flow of water in Red n Mountain Creek and provide a 30 day residence time. The combina- U tion of limestone addition and diversion of water above the 1200 P level through the Treasury Tunnel shall yield a near neutral pH in Red Mountain Creek prior to entering the reservoir. c. Sediment Collection Pond: The sediment collection pond shall be sized to collect coarse material in order to reduce U sedimentation in the reservoir. p d. Passive Treatment System: The treatment system shall be designed to minimize heavy metal loading to the Uncompahgre I j River, and shall meet effluent limitations applicable pursuant to the Colorado Water Control Act and should to the greatest extent n U practicable achieve water quality standards specified in section p 4.2.2. Discharges from the passive treatment system shall be monitored according to section 3.7.4.1. Requirements of section i 3.7.4.8, shall also be met. -52- G ri 3,5,5 Red Mountain Creek and the Uncompahgre River Aquatic Life Z and Hydrologic Systems L 3,5,5.1 Remedial Activities I Source control remedial activities for the Red Mountain and Uncompahgre Rivers hydrologic systems are intended to minimize LJ and mitigate ground water and surface water as sources of convey- pi ors of contaminants. These activities are further intended to improve aquatic life in the Uncompahgre River. The following j j remedial activities shall be implemented: a. Conduct a comprehensive surface and aquatic biota GJ monitoring and modeling program in the Red Mountain Creek and p Uncompahgre River basins to measure and predict the performance of the below grade reservoir and other source control measures in achieving the surface water standards specified in section 4.2.2.2. Q n 3.6 REMEDIAL ACTION SCHEDULE AND MILESTONES p All remedial activities described in this document shall follow a schedule and incorporate the milestones in section 4.1. n This schedule assumes the decision to proceed occurs the first quarter of the year (January, February, or March). Plate I U shows the proposed remedial activities schedule. -53- n 0 3.7 PERFORMANCE PLAN 3.7.1 Introduction To maximize the effectiveness of the implemented remedial action, the performance plan described herein shall be conducted, with such modifications as deemed necessary by the state, to achieve the primary objectives of the project shall be made. Quality assurance/quality control (QA/QC), monitoring and a performance evaluation are interwoven into the Performance Plan (Performance Plan). Quality control ensures that the remedial activities proceed in accordance with the final plans and speci n fications; quality assurance provisions are the internal cross-checks on quality control. Monitoring assures that Li required information is available to allow comparison of actual performance with design expectations and conditions prior to con struction of the remedial actions. The performance evaluation is the vehicle by which monitoring feedback is linked to monitoring quality assurance and quality control to ensure that the results of both the design and construction effort are effective. This RAP requires development of a quality assur ance/quality control, monitoring and performance evaluation plan for all remedial activities. The Performance Plan shall be designed to assure that the remedial activities are conducted in a safe manner and the design systems and structures perform in accordance with the RAP. -54- L 3.7.2 Scope of the Performance Plan The Performance Plan shall include all remedial activities u and design criteria related to a plan for cleanup and reclamation Z of the existing facilities including but not limited to worker health and safety programs, monitoring of remedial activities L outlined in the RAP and a description of the duties of the qual- p ity control contractor. The Performance Plan shall apply to all components described in the RAP and the specified remedial activ ities. A quality control contractor shall be selected to imple- U ment, conduct, and document compliance with the Performance Plan. Pl The contractor shall be approved by the state, based upon the state's assessment of the contractor's ability to perform the work. The contractor shall report directly to designated state representatives. Q p 3,7,3 Contents of Performance Plan „ The Performance Plan shall have a definite organizational GJ structure, shall contain specific plans for inspection, sampling, n chain of custody, testing and audit procedures, methods of analy sis, authority for changes and corrective actions, and provisions U for document control, since these factors are critical to the ^ efficient and effective inspection and control of remedial activ- u -55- n ities. Where appropriate the Performance Plan shall incorporate the procedures and approaches specified in Standard Methods for n the analysis of Water and Waste Water, American Society for Test- ing Materials (ASTM), and other appropriate sources. Sampling GG and analysis shall be conducted according to standard methods, P Analytical methods shall follow state and/or USEPA authorized u quality assurance/quality control -guidance. p The Performance Plan shall also include a comprehensive soil erosion and sedimentation control program to minimize the G impacts to surface waters and aquatic life during the remedial construction phase of the RAP, 3,7,3,1 Organizational Structure That portion of the Performance Plan describing organiza tional structure shall include the following: a. A description of the quality control management orga nization; b. The number, classification, qualifications, duties, n responsibilities, and authority of personnel, including the qual u ity control contractor; P u c. The individual who shall be responsible for overall p management at the site for quality control; d. The specific authority and responsibility of all L other personnel regarding the Performance Plan; -56- GJ P e, A program for information flow among workers, con struction management, and inspectors about various QC/QA, and D health safety requirements of the RAP; and n f, A health and safety plan which describes those activ- Z ities necessary to assure public and worker health and safety. The Performance Plan shall include industrial hazards control, monitoring, and emergency procedures, p 3,7,3,2 Surveys, Inspection, Sampling, and Testing The portions of the Performance Plan describing the n U surveys, inspection, sampling, and testing shall include the fol- p lowing: a. Methods and procedures for surveys, inspections, n sampling, chain of custody and testing during all remedial activ ities; L b. The necessary qualifications of individuals perform- p ing surveys, inspections, sampling, and testing; and c. The number and type of surveys, inspections, and/or n tests to be conducted, d. Auditing procedures to follow for all sampling and Ll testing. -57- 3.7.3.3 Changes and Corrective Actions The methodology for implementing changes and corrective actions shall be detailed in the Performance Plan and shall include: a. Identification of the person who has authority to reject work or material, to require removal or replacement, to specify and require appropriate actions if it is determined that G the quality assurance/quality control, personnel, instruction, controls, tests, records are not conforming to contract plans and specifications. 3.7.3.4 Documentation Requirements Documentation requirements shall include the following: a. The identification of the person who has authority to provide for the submittal and/or storage of all survey, test, and inspection reports; b. Specification of reporting requirements forms, formats, and distribution of reports; c. A description of record keeping to docimient construc tion methods and results, surveys, sampling, testing, and inspec tion of construction (samples of forms and records shall be included); and d. Provisions for permanent document and data storage. -58- 3.7.4 Compliance Monitoring Activities 3.7.4.1 Surface Water Monitoring A surface water sampling program shall be initiated prior to the commencement of remedial activities. The purpose of this sampling program is to determine baseline conditions, monitor changes in water quality over time during construction, and to determine water quality improvement in the San Miguel River, Red u Mountain Creek and the Uncompahgre River, This sampling program will be integrated with the ground water and aquatic life monitoring programs in order to develop an overall compliance monitoring scheme, to determine if the ground water is affecting surface quality and aquatic biota, and to determine if further remedial actions are necessary. Programs for baseline sampling and ongoing sampling will include, at a minimum, the locations, periods, and constituents described below: Sample Locations Water quality samples shall be collected at the following locations: Q U SAN MIGUEL RIVER G a, San Miguel River immediately below the confluence of -59- Ingram and Bridal Veil Creeks; b, Marshall Creek upstream of county road; c, San Miguel River below confluence of Marshall Creek; d, Royer Gulch above the influence of tailings pile Nos, 1-4; e, San Miguel River below confluence with Royer Gulch; f*, San Miguel River below tailings pile Nos, 5 and 6, below the confluence with Bear Creek; g, San Miguel River below the town of Telluride; h, San Miguel River at Society Turn; i*, San Miguel River prior to the confluence with the South Fork of the San Miguel River; j, San Miguel River downstream of the confluence with the South Fork of the San Miguel River, •Compliance points for the Standards shown in Table 4,1. RED MOUNTAIN CREEK - UNCOMPAHGRE RIVER a. Red Mountain Creek downstream from outlet of the pas sive water treatment system. b. Red Mountain Creek prior to the confluence with the Uncompaghre River. c. Uncompahgre River above the confluence with Red Moun tain Creek, I d*, Uncompahgre River below the confluence with Canyon -60- Creek. •Compliance Point for the standards shown in Table 4.2. Cl Sample Periods Each sampling location shall be sampled on a quarterly basis for a 5 year period (60 months) or until all remedial activities are completed. Thereafter, sampling shall take place G once every six months until there is no statistically significant change in the water quality. Constituents For the San Miguel River, Red Mountain Creek, and the Uncompahgre River, the following constituents shall be monitored: CONSTITUENT Arsenic*** Cadmium Alkalinity(l) Copper Hardness Chromium** pH(l) Lead Flow(l) Iron TSS* Manganese Zinc * Total Suspended Solids ** For the San Miguel River only. *** For Red Mountain Creek and the Uncompahgre River only. (1) Field Measurements 3.7.4.2 Ground Water Monitoring A ground water monitoring program shall be initiated prior o u -61- n. p to the commencement of remedial activities. The purpose of this sampling program is to determine baseline ground water condi- ) tions, monitor changes in ground water quality over time, to determine if ground water quality is adversely affecting surface GJ water quality and aquatic life, and to determine if additional p remedial actions are necessary. A program for ground water monitoring in the site area p j shall be conducted. The ground water monitoring program shall be integrated with the surface water monitoring program. All wells L shall be completed in the shallow alluvial aquifer. This program P must include the locations, depth, completion interval and u details of all monitoring wells, and the sample periods and field I and chemical analyses to be performed. This program must include at a minimum the following wells, sampling periods, and chemical Z analyses. 0 Well Locations ^ Ground water quality of the Telluride Valley area shall be n monitored at the following locations: ri a. MWIL-4(1) - downgradient of the infiltration lagoons; b. MW-TP4(1) - downgradient of tailings pile Nos. 1-4; -62- u 0 p c. MW-TP5 - between tailings pile No. 5 and the San Miguel River; / d. MW-20(1) - between tailings pile No, 6 and the ^ San Miguel River; Gj e. MW-3,4,5 - (3 wells) a line of wells across the p valley downgradient of tailings pile No. I / u 6 between the pile and Bear Creek; I I f, CW-l(l) - the city wells in City Park g, CW-2(1) - the city wells in City Park n side of San Miguel River; LJj h, MW-6 - western edge of City Park on the south i, MW-7 and 8 - (2 wells) downgradient of the passive u water treatment system. (1) Existing Wells p Ground water quality for the Red Mountain Valley area shall u be monitored at the following well locations: 0 a, GW-1,2 - (2 wells) southeast side of Red Moun tain Creek immediately below tailings pile No, 4; b. GW-3 - west side of Red Mountain Creek in Ironton Park in the area of Crystal Lake, -63- Sampling Periods Monitoring and analyses shall be conducted for all sampling locations on a quarterly basis for a 5 year period (60 months) or until all remedial activities are completed. After that period, sampling shall continue on a quarterly basis (once every 3 months) during high and low flow conditions for a period of 10 years. p Field and Chemical Constituents All monitoring wells shall be sampled and analyzed for the following constituents: Constituent Constituent Arsenic Manganese Cadmium Zinc Chromium* pH(l) Copper Alkalinity(l) Lead Iron Temperature(l) *Telluride Valley wells only (1) Field Measurements -64- pj 3,7,4.3 Aquatic Life Monitoring Ij A monitoring program shall be initiated for aquatic life G^ prior to the commencement of remedial activities at the site. n The purpose of this program is to determine the baseline aquatic conditions, monitor changes in these conditions over time and to determine if the amount of remediation is adequate. „ The aquatic life monitoring program will include at a mini- ^J mum the locations, periods, and constituents described below: Q Sampling Locations: [J The general sampling locations are: P 1. The San Miguel River below Bear Creek. 0 2. The San Miguel River immediately above Society Turn. n 3. The San Miguel River above the confluence with the South Fork. n 4. The San Miguel River below the confluence with the South Fork. 5. Red Mountain Creek above and below Ironton Part. 6. The Uncompahgre River above Red Mountain Creek. 7. The Uncompahgre River below Red Mountain Creek. 8. The Uncompahgre River below Ouray. 9. The Ridgway Reservoir. Sampling Periods Frequency and Constituents; -65- p Fish populations shall be monitored on an annual basis at all stations. A multiple pass methodology shall be used to determine biomass, length frequency distribution, and condition n factor. The sampling shall be performed during the months of U April and July at low flow conditions to determine status of res- p ident trout populations. Once every 3 years the concentrations of cadmium, copper, P \ / and zinc shall be measured in the muscle tissue, kidney, and U n liver of fish. Four stations would be sampled. Thirty fish of each age class of the species shall be collected and monitored at each station. Collection of fish will be accomplished during the annual sampling effort. Bioassays shall be performed utilizing Brown Trout eggs and fry as they relate to winter and spring metals concentrations in n the San Miguel River and the Uncompahgre River. 3.7.4.4 Air Quality ~J An air quality permit will be required and must be obtained P prior to commencement of remedial activities to monitor the effectiveness of the remedial actions for reducing or eliminating I fugitive dust exposure to the residents of Telluride. -66- 3.7.4.5 Soil Testing Program A comprehensive soil testing program shall be initiated prior to the commencement of remedial activities at the site. The purpose of this program is to determine base line conditions, to determine the appropriate cleanup method for a given contain ment level, to confirm the effectiveness of the remedial action taken and determine if additional remedial actions are necessary. z Soils monitoring shall include two distinct parts; 1) z populated soils; and, 2) unpopulated soils. The sampling and testing program for populated and unpopulated soils shall include, at a minimum, the following: Sampling Location: Systematic sampling programs for the following remedial activities and associated locations shall be conducted: a. Telluride Valley: Tailings pile Nos. 1-4, Pandora Millsite, Town of Telluride and future growth areas, and miscel z laneous tailings along the San Miguel River, including the Society Turn area. b. Red Mountain Creek Valley: Tailings pile Nos. 1-3, buried tailings pile, and the Millsite. n Sampling at these locations shall be based on the guide lines outlined in "Soil Sampling Quality Assurance User's Guide" -67- n (Barth and Mason, 1984); and in U.S.E.P.A. Publication No. I I LyJ EPA-560/5-85-026, August 1985, entitled "Verification of PCB Spill Cleanup by Sampling and Analysis" for PCB's. Chemical Constituents: Constituents Remedial Component n, Lead All pH All ^n PCB's Millsites 1,1,1 Trichloroethane Millsites o 3.7.4.6 Revegetation 0 — Revegetation is required in order to stabilize and protect J the disposal area caps from water and wind erosion, reduce wind- Cj blown dust from the cap surface and reduce infiltration through the cap by enhancing evapotranspiration. A monitoring program for the revegetation effort on the tailings pile caps shall be implemented to determine their effectiveness and to determine if GJ additional remedial actions are necessary. The monitoring pro- n gram shall be developed to determine if the revegetation criteria set forth in section 4.2.4 has been met. n 3.7.4.7 Construction Monitoring A monitoring program for major construction activities U -68- n p shall be initiated prior to commencement of remedial activities. The purpose of the construction monitoring is to assure that con- \ struction activities shall be performed according to the final designs and specifications. Construction monitoring together L with compliance monitoring are used to verify that the facilities n, constructed are performing adequately. The construction monitor ing program must, at a minimum, include diversion ditches, tunnel \ I plugs or restrictors, waste repositories, soil erosion and sedi- mentation control measures, and water treatment system(s). U Appropriate monitoring methods shall be instituted for all major O construction activities. 0 3,7.4.8 Water Rights All remedial actions involving the diversion and/or use of ground water or surface water or storage must comply with Colo rado statutes and the rules and regulations of the State Engi neer. 3.8 COMPLIANCE FRAMEWORK A four-phased compliance framework shall be followed so that the RAP can be efficiently implemented and the results of the remedial actions can be effectively evaluated. These phases G are as follows: n Phase I - Design Investigations -69- .n u n u Phase II - Final Remedial Design U Phase III - Final Construction Reports Phase IV - Certification Report Phase I requires detailed design investigations. These design investigations are intended to provide adequate informa tion so that the remedial actions in this RAP can be appropri ately designed. Phase II consists of preparing final plans and specifications and a performance plan. The Performance Plan shall include a quality control and quality assurance program, n and a monitoring and performance evaluation plan. Phase III entails preparation of a final construction report as each reme U dial component, or specific subset of same, is completed. Phase I 1 IV consists of the preparation of a certification report that docimients the completion of the remedial actions described U herein. p The compliance framework shall be implemented in the fol- L^ lowing manner: p a. The detailed design investigations shall be conducted in accordance with the RAP and a design basis memorandum shall be U prepared. This information shall be used as the basis for pre- p paring detailed plans and specifications and the Performance Plan. j b. Final plans and specifications and the Performance Plan for all remedial activities shall be provided 3 months prior ri -70- n G n LJ p to construction. All remedial activities shall be performed in : L accordance with the plans, specifications, and procedures pre- n scribed by these documents. Where the RAP is silent on specific u matters routinely addressed by applicable licenses and permits, J implementation will be according to the licenses and permits, n c, A final construction report shall be submitted immediately after remedial activities for each plan component are j / completed. These documents shall include as-built drawings, quality control surveys and test results, and construction sur- P L veillance information. State approval of the final construction p report for a given area shall signify completion of construction activities in accordance with approved final plans and specifica tions for that area. 3,9 PUBLIC HEALTH ASSESSMENT PROGRAM p 'i 3,9,1 Health Effects U p A public health program including additional health assess- LJf ment studies shall be instituted to protect the health and wel- C fare of the citizens of the Town of Telluride. The public health _l program shall be conducted in cooperation with the Town of ~i \ Telluride. The health program shall include at a minimum: 1) evaluation of the cancer rate information for those living in the L community, 2) establish a registry of adverse reproduction p outcomes among women of childbearing age and among a comparison ^ • -71- n group, 3) establish an ongoing system for screening for elevated c metals' levels in biological specimens for those at risk, and 4) n development of an ongoing program for monitoring children for the LJ adverse health effects of metal exposure, including but not GJ restricted to, neuropsychological abnormalities. The occurrence p of these abnormalities should then be compared to rates found for Colorado and the United States. U 4.0 IMPLEMENTATION SCHEDULE AND COMPLIANCE STANDARDS The remedial activities described in section 3.0 shall be p implemented in accordance with the following implementation milestones and compliance criteria. p J ' 4.1 IMPLEMENTATION MILESTONES U A time schedule for all remedial activities is set out on p Plate I. This schedule assumes that approval of this Record of ^ decision by the court occurs during the first quarter of the year / (January, February, or March 1987). All design investigations P shall be completed within 7 months of the decision to proceed U (approval of this Record of Decision by the court). Under the p schedule proposed, the design investigations would occur during 1987. All final designs and specifications shall be completed j within 15 months of the decision to proceed (spring 1988). All construction activities would be completed in the fall of 1991 ^ -72- p under this schedule. u n 4.2 COMPLIANCE STANDARDS u The remedial activities at the site shall be performed in n compliance with all applicable or relevant and appropriate envi- p ronmental and facility siting laws. The remedial action in this case is not undertaken pursuant to section 104 or 106 of the Com- ]•' prehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments and P L Reauthorization Act (SARA), 42 U.S.C. sec. 9604 and 9606 (1986), p respectively. Therefore, the remedial action selection process set out in section 121 of SARA, 42 U.S.C, sec. 9621 (1986), is [' not strictly applicable. Nevertheless, Colorado has determined ^ cleanup levels for the Idarado site in general comformity with GJ SARA section 121 and in accordance with the National Contingency UP Plan. At a minimum, the remedial action must obtain a degree of n cleanup of hazardous substances, pollutants, and contaminants L released into the environment and of control of further releases P which assures protection of human health and the environment. C Consistent with SARA section 121(d), Colorado has also identified P relevant and appropriate state statutes and regulations which the remedial action must meet. The applicable or relevant and appropriate requirements are detailed below and/or summarized in this section. All activities -73- n G' P affecting surface water must comply with the Colorado Water Qual- ^ ity Control Act (sections 25-8-101 through 25-8-612, C.R.S. (1986 Supp.)). Stream classification and water quality standards apply for all pollutants except the numeric standard selected for zinc P U and lead in the mainstem of the San Miguel River and zinc, cop- P per, and lead in the Uncompahgre River. In order to assure pro tection of human health and the environment, Colorado has deter- P mined that a numeric standard of 0.15 mg/l of zinc and the Colo- rado Basic Standard of 0.004 mgll of lead are relevant and appro- PGG Uncompahgrpriate to eprotec Riverst .th e Coloradaquatico communithas alsoy determinein the Sad n thaMiguet thl e anColod rado Basic Standards for lead on the San Miguel River and copper and lead on the Uncompahgre are relevant and appropriate as goals 0 for the remedial action. All point source discharges must at a -^ minimum meet effluent limitations and Colorado Discharge Permit P System (CDPS) requirements. Moreover, the antidegradation and basic standards of 5 CCR 1002-8, at 3.1.8 and 3.1.11 (1-84) apply I j to all surface water. Regarding ground water cleanup levels, the Colorado Safe LJ Drinking Water authorities (sections 25-1-107(1)(x) and (y) and P 25-1-114 and 25-1-114.1, C.R.S. (1986 Supp.)) and the Colorado Primary Drinking Water Regulations are applicable standards for p J the ground water at the site which may be a source of municipal water supplies. Surface water stream segment, certain other sur- G -74- n L n face water, antidegradation, and basic standards are also rele u vant and appropriate for the ground water to the extent that the ground water prohibits surface waters from being able to achieve such standards. The Basic Standards for Ground Water (5 CCR 1002-8, at 3.11.0 to 3.11.9 (1-87)) are also relevant and appro priate to the remedial action. Any sewage treatment works within the site shall conform to Domestic Wastewater Treatment Works n Regulations (5 CCR 1002-12, at 2.2.0 to 2.2.7 (12-81)). Any u dredge, fill, or stream realignment activities or remedial p actions affecting wetlands must comply with 401 certification p requirements (5 CCR 1002-18, at 2.4.1 to 2.4.9 (7-85)). The relevant and appropriate standards for soils are dis- ~J cussed in section 4.2.1 herein. These standards are based upon C human health considerations, including recommendations of the n pl Colorado Department of Health (CDH) and the Agency for Toxic Sub- p stances and Disease Registry (ATSDR), as well as environmental ^ protection. L The remedial action must comply with the Colorado Air Qual ity Control Act (sections 25-7-101 to 25-7-505, C.R.S. (1986 p Supp.)) and the Colorado Air Quality Control Regulations and n Ambient Air Quality Standards promulgated thereunder (5 CCR 1001-1 to 1001-14). As required by the Air Quality Control Act and regulations, preconstruction permits must be obtained. In Ui particular, all remedial activities must meet the requirements of -75- Z u p LG Air Quality Control Regulation Nos. 1 and 8 and the ambient air LJ quality standard for total suspended particulates. Additionally, L if a fine particulate standard (PMIO) is adopted, compliance with P that standard will be required, L Vegetative density requirements, set forth in section Gl 4,2,4, are relevant and appropriate to insure adequate protection of air quality and surface and ground water quality, L All remedial activities must be conducted in conformance p with the Colorado Mined Land Reclamation Act (sections 34-32-101 ^y through 34-32-125, CR.S, (1984)) and regulations promulgated n thereunder. The hazardous waste treatment, storage, and disposal L requirements established by the Colorado Hazardous Waste Act n PI (sections 25-15-101 through 25-15-313, C.R.S. (1986 Supp.)) and n the Colorado Hazardous Waste Regulations (6 CCR 1007-3, (9-85)) J are applicable to the organic chemicals found on site. The dis- Lu posal requirements under the Toxic Substances Control Act (TSCA) (15 U.S.C. sees. 2601 through 2629, (1984)) are applicable to the P J PCB contaminated materials found at the site. p At a minimum, remedial activities must be conducted in con- formity with the following Colorado statutes and regulations: n 1. The Colorado Wildlife Act (sections 33-1-101 to 33-1-120, C.R.S. (1984)); P J 2. The Nongame and Endangered Species Conservation Act pun (sections 33-2-101 to 33-2-108, C.R.S. (1984)); -76- G n 3. wildlife Enforcement and Penalty provisions, (sec- GJ tions 33-6-101 to 33-6-130, C.R.S. (1984)); L 4. The Colorado Historical, Prehistorical, and Archaeo- P logical Resources Act (sections 24-80-401 to 24-80-410, C.R.S. ^ (1982)); ~| 5. The Colorado Ground Water Management Act (sections 37-90-101 to 37-90-141, C.R.S. (1986 Supp.)); P J 6. The Water Well and Pump Installation Contractors Act (sections 37-91-101 to 37-91-112, C.R.S. (1986)); n 7. The Reservoirs Act (sections 37-80-101 to 37-80-125, G C.R.S. (1986)); 8, The Water Rights Determination and Administration Act P J (sections 37-92-101 to 37-92-602, CR.S, (1986 Supp,)); 9, The Water Well and Pump Installation Contractors G Regulations (2 CCR 402-2, (12-72)); 10. The Well Permit Regulations (2 CCR 402-4, (7-82)); 11. The General Provisions of the Division of Wildlife Regulations (2 CCR 406-0, (2-87)); and 12. The Reservoir Dams Regulations (2 CCR 402-1, (9-77)). The remedial activities at the site shall be performed in order to achieve compliance with the foregoing Colorado statutes and regulations and the standards set out more specifically below. Determination of compliance shall be achieved through monitoring activities as detailed in sections 3.7.4 and 3.8 of -77- this ROD. L n 4.2.1 Soils u LJ The soils within the study area can be categorized as popu- C lated soils and unpopulated soils. Populated soils are defined as soils in the vicinity of areas -where the primary existing and P J potential land use is residential. Unpopulated soils are those u soils upon which food for human or animal consumption is grown, or which have a potential for commercial development, or which C inay be subject to other human disturbance. n J 4.2.1.1 Populated Soils —• ^ For populated soils, Colorado has determined, based on the n information and analysis of the federal ATSDR, that the remedial U activity must follow the soils cleanup methodology in section p L 4.2.1.3 to protect human health, because of the potential direct P ingestion pathway which may result in adverse human health effects. The cleanup of lead will reduce other heavy metals of G concern. The populated soils which must comply with these cleanup levels are all properties within the limits of the Town of Telluride, residential areas near the Town of Telluride, and -78- n residentially zoned areas for the town. 4.2.1.2 Unpopulated Soils To assure adequate protection of human health and the envi ronment due to possible vegetative uptake, direct consumption by animals and phytotoxicity, remedial activities for unpopulated soils must follow the soil cleanup methodology set forth in section 4.2.1.3. Cleanup of the lead soil content will also result in reduction of the other heavy metals of concern. P L The areas which must comply with these cleanup levels are all sites where tailings are being removed for consolidation, in nonresidential areas outside the city limits of Telluride, the Pandora Millsite and miscellaneous tailings in riparian areas. 4.2.1.3 Soils Cleanup Methodology n J The cleanup methodology for populated soils located within p the boundaries of the Town of Telluride, residential areas near the town and future growth areas of the town are as follows: a. Soils with lead levels in excess of 1000 mg/kg (dry weight) as determined from soil material passing a 2 millimeter n L mesh shall be removed, covered, sodded, mixed, treated, or other- --1 wise addressed through institutional controls, as appropriate. -79- G b. Soils with lead levels in excess of 500 mg/kg (dry weight) shall be covered, sodded, mixed, treated or addressed L through institutional controls as appropriate. In some cases no n action may be taken. ! 1 The cleanup methodology for unpopulated soils in the Gl Telluride Valley and beneath the removed tailings ponds in the U Red Mountain Creek area are as follows: L a. Soils with lead levels in excess of 1,000 mg/kg (dry p weight) as determined from soil material passing a 2 millimeter mesh shall be removed, covered, mixed or treated as appropriate, b. Soils in steep or well-vegetated terrain in n unpopulated areas may not need to be removed, covered, mixed, or _l treated depending upon the environmentai sensitivity of these n areas. G 4.2.2 Surface Water 4.2.2.1 San Miguel River G Surface water in the San Miguel River is not currently used P-, as a drinking water source in the Telluride Valley. However, it '—' is utilized as an aquatic habitat for fish and as a recreational n fishing area. In order to protect human health and the aquatic L life in the San Miguel River, the stream classifications and water quality standards for the San Miguel mainstem shall be used ^ -80- p for surface water cleanup (with the exception of the numeric standards for zinc and lead). L 0 TABLE 4.1 SURFACE WATER ~ SAN MIGUEL RIVER PARAMETER CONCENTRATION (mg/l) D.O. 6.0 u 7.0 (spawning) Fecal Coliforms 200/100 (ml) NH3 0.02 (unionized) CL2 (residual) 0.003 Cyanide (free) 0.005 S as H2S 0.002 (undissolved) Boron 0.75 Nitrite 0.05 n Arsenic 0.05 u Cadmium 0.0004 Trivalent Chromium 0.1 Hexavalent Chromium 0.025 Copper 0.005 Lead 0.004* -81- LJ G Mercury 0.00005 Nickel 0.05 J Selenium 0.02 p . Silver 0.0001 ^ Zinc 0.15* n Iron 1.0 iJ n Manganese (total) 1.0 The pH shall remain between 6.5 and 9.0 standard units. *Consistent with the NCP and SARA sec, 121(d), in order to assure protection of human health and the environ ment, Colorado has determined that a concentration of 0,15 mg/l zinc is relevant and appropriate. Higher concentrations will result in undue stress and metal loadings to the aquatic community. The Colorado Basic Standards concentration of 0.05 mg/l for zinc and 0.004 mg/l for lead are relevant and appropriate as goals. The compliance points for surface water in the San Miguel River are the San Miguel River below the confluence with Bear Creek and the San Miguel River above the confluence with the South Fork Compliance sampling shall be conducted as part of the moni toring system described in section 3.7, Performance Plan, Surface Water Monitoring. -82- P u up n L 4.2.2.2 Uncompahgre River and Red Mountain Creek Surface water in Red Mountain Creek does not currently sup port aquatic life. It does significantly degrade the Uncompahgre River. The stream classifications and water quality standards G for the Uncompahgre River mainstem (except the numeric standards for zinc, copper, and lead), shall be applicable to the Uncompahgre River. The compliance point for surface water is the Uncompahgre River below the confluence with Canyon Creek. TABLE 4.2 SURFACE WATER ~ UNCOMPAHGRE RIVER PARAMETER CONCENTRATION (mg/l) D.O. (dissolved oxygen) 6.0 7.0 (spawning) Fecal Coliforms 200/100 (ml) p L NH3 0.02 (unionized) CL2 (residual) 0,003 Cyanide (free) 0,005 S as H2S 0.002 (undissolved) n Boron 0.75 L n -83- LC Nitrite 0.05 Arsenic 0.05 J Cadmium 0.0004 P Trivalent Chromium 0.1 LJ Hexavalent Chromium 0.025 n Copper 0.005* I Lead 0.004* p Mercury 0.00005 p Nickel 0.05 ^ Selenium 0.02 n Silver 0.0001 Zinc 0.15* P J Iron 1.1 (-, Manganese 1.0 The pH shall remain between 6.5 and 9.0 standard units, n L *See note in Table 4.1, above. A concentration of 0.15 mg/l zinc is relevant and appropriate. The Colorado Q Basic Standards concentrations of 0.05 mg/l zinc 0.005 P mg/l copper, and 0.004 mg/l lead are relevant and \ appropriate as goals. C Compliance sampling shall be conducted as part of the moni toring program described in section 3.7, Performance Plan, Sur- n U face Water Monitoring. -84- z G 4.2,2,3 Point Source Discharges All point source discharges from the Idarado site must com ply with Colorado Discharge Permit System requirements as estab U lished in the Colorado Water Quality Control Act (sections P 25-8-501 to 25-8-507, C,R,S, (1986 Supp.)) and the State Dis J charge Permit System Regulations promulgated thereunder (5 CCR G 1002-2, (10-83)). In addition, discharges from all points sources, including G inter alia, water treatment systems, both active and passive, shall meet applicable effluent limitations established by the Colorado Water Quality Control Act (section 25-8-205, C.R.S. (1982)) and the Effluent Limitations Regulations (5 CCR 1002-3, (6-85). In no event shall the effluent limitations exceed the standards set out in Table 4.3. TABLE 4.3 EFFLUENT LIMITATIONS PARAMETER 7-Day Average 30-Day Average BOD 5 45 mg/l 30 mg/l Suspended Solids 45 mg/l 30 mg/l Fecal Coliforms* -85- P L Residual Chlorine less than 0.5 mg/l Oil and Grease 10 mg/l, no visible sheen. *To be determined as necessary to protect public health. G 4.2.2.4 Antidegradation and Basic Standards G p. The remedial action shall enable all surface waters im- "L pacted by the Idarado site to attain the antidegradation standard P and the basic standards which are applicable to all waters of the L 1002-8, at 3.1.8 (1-84), precludes water quality degradation u state. The antidegradation standard, established in 5 CCR which would interfere with, or become injurious to, existing uses. The basic standards, established pursuant to 5 CCR 1002-8, at 3.1.11 (1-84), are applicable to all waters of the state and provide as follows: Substances attributable to human-induced discharges, ... not otherwise controlled by permits ... shall not be introduced into the waters of the state: (a) which can settle to form bottom depos its detrimental to the beneficial uses. Deposits are stream bottom buildup of mate rials which include, but are not limited to, anaerobic sludges, mine slurry or tail ings, silt, or mud; or u (b) which form floating debris, scum, or other surface materials sufficient to harm existing beneficial uses; or -86- (c) which produce color, odor, or other conditions in such a degree as to create a nuisance or harm existing beneficial uses or impart any undesirable taste to signifi cant edible aquatic species or to the water; or n (d) in amounts, concentrations, or combina- ^ tions which are harmful to the beneficial uses or toxic to humans, animals, plants, or aquatic life; or (e) in amounts, concentrations or combina- n tions which produce a predominance of L undesirable aquatic life; or (f) in concentrations which cause a film on the surface or produce a deposit on shorelines. The basic standards for organics shown in Table 4.4 are also applicable to all waters of the state. TABLE 4.4 ORGANIC PARAMETERS PARAMETER CONCENTRATION (mg/l) PCB 0.000001 Chlorophenol 0.001 Monohydric phenol 0.5 Gl L G -87- Q 4.2.3 Ground Water Ground water within the San Miguel River alluvium has been investigated by the Town of Telluride as a domestic drinking water source. This source of drinking water may need to be used in the future. The ground water also flows into the San Miguel River, and has an effect on surface water quality. Accordingly, n in order to assure adequate protection of human health and wel fare, Colorado has determined that, with the proposed remedial action, ground water in the San Miguel River Valley shall improve over time and shall meet the following combination of Colorado's primary and secondary drinking water standards as set forth in Table 4.5. It is projected that ground water quality will improve in the future so as to minimize impacts on water quality in the San Miguel River and aid in the attainment of standards set forth in Table 4.1. Ground water in the Red Mountain Creek Valley is not cur rently used as a source of drinking water, nor is any such use anticipated in the near future. Accordingly, the values shown in 0 Table 4.5 are not applicable in the Red Mountain Creek Valley at this time. -88- p LJ G P TABLE 4.5 U GROUND WATER PARAMETER CONCENTRATION (mg/l) Arsenic 0.05 P Barium 1.0 Cadmium 0.01 Chromium 0.05 n Lead 0.05 Mercury 0.002 Nitrate (as N) 10.0 Selenium 0.01 Silver 0.05 Zinc 5.0 The pH shall remain between 6.5 and 9.0 standard units. The compliance points for ground water will be at monitor n ing wells MW-3, 4, and 5 downgradient of Telluride tailings piles Nos. 5 and 6. The basic standards for ground water (5 CCR 1002-8, at 3.11.0 through 3.11.10 (1-87)), are relevant and appropriate and, therefore, must be met by the remedial action. Compliance sampling will be conducted as part of the moni- -89- toring program described in section 3.7, Performance Plan, Ground Water Monitoring. 4.2.4 Vegetation n Establishment of permanent, self-sustaining vegetation will u be required to assure stability of tailings containment areas, Pj tailings removal areas, and other disturbed areas against surface water and wind erosion. The vegetative communities to be estab Q lished for stabilizing tailings containment and removal areas shall be designed on the basis of ecological response units present at the sites, the required functions of the vegetation (e.g. evapotranspiration), and site potential. Undisturbed vegetative communities (primarily herbaceous) occupying ecologi cal response units similar to those anticipated at the tailings containment and removal areas and other miscellaneous disturbed areas will be inventoried to determine the major species (e.g. those providing more than 5 percent of the species comprising the undisturbed community), and the essential ecological niches to be provided in the revegetation program. Similarly, avalanche chutes and other naturally revegetated disturbed areas supporting well developed stands of herbaceous vegetation will be assessed in the immediate vicinity of the tailings areas. The revegetation specifications will be designed to establish the -90- 0 0 major species identified in these inventories or more readily available species which occupy similar niches due to growth form (e.g. cool season sod forming grasses, bunch grasses, nitrogen fixing legumes, native forbs, shallow rooted shrubs) and adaptive characteristics such as drought resistance, soil type affinity, p shade and sun tolerance. u Performance of the revegetation program will be evaluated using a combination of constructed and natural reference areas. Constructed vegetation reference areas will be established for R LJ purposes of evaluating the tailings containment revegetation pro- p gram. The soil substrate for the constructed reference areas shall be prepared in the same manner as the tailings cap is to be G constructed, including provision of a low permeability layer. A sufficient number and sizing of reference areas shall be con- U structed to provide for statistical comparison of vegetation in p the various ecological response units on the tailings containment facility. Natural reference areas will be identified and secured j for purposes of evaluating revegetation efforts at tailings and mine waste removal areas and other miscellaneous disturbed areas, n U Evaluation criteria for revegetation will at a minimum p address species composition and total vegetative cover. Species composition criteria shall be established by the state for each ecological response unit based on the inventories. Species com position criteria will identify the major species by growth form -91- and adaptive characteristics which must contribute at least 3 percent of the relative cover. No one species shall contribute more than 60 percent of the total cover. The total cover criter ion shall be, at a minimum, 90 percent of the mean vegetative cover at the applicable reference area with 90 percent confi dence. In addition, all revegetation activities must comply with the requirements of Colorado Mine Land Reclamation Act (sections 34-32-101 to 34-32-125, C.R.S. (1984)) and regulations promul gated thereunder. Specifically site revegetation must meet the requirements of section 34-32-116(1)(f), C.R.S. (1984). 5.0 SELECTION RATIONALE The Remedial Action Plan (RAP) in section 3 is a compila tion of the most cost-effective, and technically feasible and reliable, options for each waste source presented in the Feasi bility Study which permanently and significantly reduce the volume, toxicity or mobility of the hazardous substances at the site. The remedy selected most closely approaches the level of protection required by legally applicable or relevant and appro priate standards, requirements, criteria or limitations. In se lecting the remedial actions to be undertaken, the state's efforts have been directed at controlling sources of contamina u tion from the site to soils, water and air. Consideration has n -92- been given to implementing permanent and effective remedies that Z do not require the transportation of large quantities of mate- p rials through residential areas. The Idarado Mining and Milling Complex covers a large land I area, approximately 13 square miles. Numerous sources and path ways for releases of hazardous substances exist. The complex J interaction of the sources and pathways as well as the environ- P mentally sensitive nature of the area was considered in the se lection of the options in the Remedial Action Plan. Selection of the options is also based on long-term effec n tiveness of reducing present. . and future threats to human health <~J and the environment, minimizing long-term maintenance costs and p achieving a permanent solution. Persistence, toxicity, mobility and bioaccumulation potential of the contaminants were also con- j sidered in the remedy selection as well as consistency with the goals and requirements of the Solid Waste Disposal Act and CERCLA GG as amended by the Superfund Amendments and Reauthorization Act. p The Idarado Feasibility Study presented numerous options for each waste source that were compiled to form a comprehensive 1 I set of alternatives. The remedial options evaluated in the feasi bility study ranged from complete removal to no action. The no Z action alternatives for contaminant sources (tailings and waste LpJ piles, mine portal discharges and onsite organic materials) were rejected because of the documented releases to the environment -93- G Pl and the potential for future releases to occur. The total removal alternative was rejected due to the large volumes of [j material involved, the high cost of transportation and disposal, the possible threats to public health and safety during remedi- L ation, and the potential for large scale environmental problems p associated with offsite disposal. When combined with the mar- ^ ginal increase in effectiveness, it is the states's conclusion P that onsite land disposal is the most cost-effective, technically feasible and safe method for handling these waste materials. U The following section presents a discussion of the effec- p tiveness and associated costs of each option that composes the aggregate selected remediation. G Li 5.1 TAILINGS 5.1.1 Selected Option U Consolidation of all tailings piles to the three tailings disposal areas (two in the Telluride Valley and one in the Red Mountain Creek Valley) placement of multilayered cap with revegetation and hydraulic improvements with flood control was the selected option for tailings material. The cost of this option is estimated to be $21,265,890 and it will reduce releases by 85 percent to 95 percent of ground water, surface water and air. GP 5.1.2 Rejected Options -94- p u p a. Removal offsite b. Backfill mine P c. Direct revegetation c d. No action Q 5.1.3 Selection Rationale P The selected option: (1) is -reliable and very effective in I reduction of metals loadings and human exposure; (2) is a low maintenance operation; (3) causes minimal environmental disturb- J ance during construction; and (4) provides for the permanent dis- p posal of the tailings. Although removal offsite provides comparable or marginally / higher efficiency, it was rejected due to large environmental construction disturbance, the short term and long term potential L for adverse health effects from offsite disposal of the tailings P relating to blowing dust, traffic accidents, the long term prob lems associated with the future disposal of the tailings and I extreme costs. Based upon the feasibility, practicality and technical reliability of capping the tailings piles, the offsite P Remilling of the tailings was rejected due to the uncer U disposal alternative was not selected. LJ tainty of the technology available to remove metals to necessary rn levels, the long time frame involved in remilling and the lack of an adequate disposal site. Remilling would require either the -95- G construction of a new more efficient mill or a leaching type Q operation. Both options would require a disposal site for future tailings disposal. A new mill would also require slurrying of tailings which would produce more contaminated water during the mill operation. A leaching operation would take many years to complete and questions exists about the removal of lead and zinc by this process. Mine backfilling was rejected due to technical uncertainty Z of effectiveness, questions about future releases of mine water from other points, about its effectiveness as a permanent solu tion, and the possibility that it would preclude future mining. Backfilling of mines is a proven technology that is cur rently being used in Canada and other countries. However, uncer tainties do exist with backfilling including the path of any P water in the mine, the quality of the water, the ultimate point of release and the lack of control of future releases. The many miles of interconnected workings and numerous portals make the prediction of outflow points and the water quality of the outflows extremely difficult. Other problems are the accessibil ity to some areas of the mine and the possible detrimental effects on future operations. All of the tailings cannot be placed back into the mine. Thus, some tailings (approximately 36 percent) would have to be remediated at the surface. For these reasons, consolidation and capping of the tailings was considered -96- G p to be more effective than backfilling. Direct revegetation was rejected due to insufficient effec- I tiveness in permanently reducing wind and water erosion, infil- tration and human .exposure, as well as the need for a high degree L of maintenance. The "sands" portion of the tailings piles are r-) highly susceptible to water erosion. Even a very thick, self 0 sustaining vegetative cover would .require maintenance in order to p limit tailings from washing into the San Miguel River or Red U Mountain Creek, L Although infiltration to ground water would be reduced by p evapotranspiration provided by the vegetation, it could not be ^ reduced as effectively as by a multilayer cap. Blowing tailings P would continue to be a problem until a thick mat of organic mate rial could be established to reduce exposure of tailings material L to the wind. Human exposure to the tailings would also remain p high since no physical barrier such as fill material would exist. Water falling directly on the piles would come in contact with I tailings material prior to being routed directly to the San Miguel River or Red Mountain Creek. The ability of the tailings l] material to foster a self-sustaining vegetative community without p continued application of water and fertilizer is uncertain a ^ best. P Consolidation of major tailings piles was accepted as a remedial measure to be undertaken at the site. Remediation of G -97- Q GJ p tailings piles in place would allow tailings piles Nos. 1 - 4 on L^ the Telluride side, the buried tailings pile and tailings pile P No. 2 on the Red Mountain side to be left in unstable areas. Tailings piles Nos. 1-4 would require extensive flood protec- P u tion measures if left in place and could still be overtopped by flooding from Marshall Creek. In place remediation is not a per manent solution for tailings piles Nos. 1-4. Consolidation of Society Turn tailings at a site near Society Turn will avoid the need to haul these materials through the Town of Telluride. An isolated disposal area with the same cap as described for tailings piles Nos. 5 and 6 will signifi cantly and effectively reduce releases from the tailings in the U Society Turn area. The buried tailings on the Red Mountain side rest in a lake that existed at the site. The water that originally filled the lake now comes in contact with tailings material. The most cost effective solution to this problem is to remove the tailings material. Tailings pile No. 2 appears to be located in a deep valley. Seeps with poor water quality currently discharge from the pile. Erosion of tailings material from pile No. 2 into Red Mountain Creek is evident from field observations. Future ero sion of the tailings piles No. 2 is a certainty. For these U reasons in place remediation of this pile will not be effective. Thus, the consolidation of these piles is preferred. -98- G P P 5.2 WASTE ROCK GJ 5.2.1 Selected Option p Z Removal of waste rock from stream courses (or reconstruc- p tion of stream courses) and diversion of run-on and portal flows, was the option selected. A sediment collection pond will be I / built at the base of Marshall Creek. The cost of this option is estimated to be $1,188,194 and it would achieve a 50 percent to U 95 percent reduction in releases to surface water. p U 5.2.2 Rejected Options } j a. Removal offsite b. Removal and consolidation of tailings piles or other GJ central location p c. No action r-i 5.2.3 Selection Rationale The selected option: (1) is reliable and effective in P reduction of metals loadings; (2) requires little or no mainte- P nance; and (3) causes minimal environmental disturbance during u construction. The environmental problem associated with waste [ rock is metals mobilization due to water leaching through waste rock. By isolating waste rock from contact with concentrated U water flows, the majority of waste rock loading of metals to sur- p face and ground waters will be eliminated. -99- P Removal offsite and removal with consolidation onto tail- ^ ings piles or a central location in the High Country was rejected P due to only marginally increased efficiency, extreme cost and Gj large environmental construction disturbance and the possible n threat to public safety during construction. Waste piles are L scattered throughout the site and in many instances are in areas G that are currently inaccessible to large earth-moving equipment P and trucks. In the High Country area and the Red Mountain Creek U area, new roads would be needed for access to the piles for L removal. These roads would cause destruction of vegetation in p sensitive areas. Reclamation at these high elevations would take tens to hundreds of years. Erosion would also be accelerated. Erosion control measures would leave more scars on the landscape. Diversion of run-on around waste piles and removal of waste mate rial from streams are reasonable actions to reduce water contact with mineralized material. These actions when combined with the settling pond on Marshall Creek and the below grade reservoir for U Red Mountain Creek will significantly reduce metal loads. In cases when stream channels are inundated with waste material, the streams will be rechannelized. Small tractors and manual labor can be employed to perform these operations. No new roads or improvements to existing roads are envisioned for waste pile remediation. No action was also considered, however, the metals loadings -100- up n coming from waste piles can be reduced effectively by the actions I i selected. No action would allow the current level of releases to P continue. Thus, the no action alternative was rejected. P 5.3 MINE WATER DRAINAGE G p 5.3.1 Selected Option Reduce inflow to the mine, divert underground mine flows J above the 1200 level via gravity from Telluride to Red Mountain P Creek, control or reroute underground mine flows, segregate poor quality mine water, collect and passively treat approximately P • . . p 8,900 gpm in a settling pond and geochemical absorption field, treat Red Mountain Creek in a below grade reservoir by mixing GJ diverted mine flows and charging the creek with limestone, plug P selected low head portals, use the existing lagoons to control P mine flow overleads and divert portal flows away from waste rock are the selected options for mine water drainage. The cost of u this entire option is estimated to be $20,693,485 and it would achieve a 50 percent to 98 percent reduction in releases to ground and surface water. 5.3,2 Rejected Options u a. Conventional active treatment of the entire flow of mine water b. Backfill mine -101- GJ p c. Biological treatment d. No action P P 5,3,3 Selection Rationale The selected option: (1) will result in significantly L> enhanced stream water quality; (2) requires low maintenance: (3) is efficient in that the poorest quality water is segregated and treated; and (4) results in less environmental construction dis turbance than the rejected options. Conventional treatment of all mine waters was rejected because of the massive active treatment plants required to treat the large volumes of water from the entire mine. The treatment P plants would cover several hundred acres and would thus result in VJ large construction disturbance and capital expenditures and oper- L ation and maintenance would be extremely costly. The need to p construct a piping system for delivery of water to a central treatment system would cause environmental disturbance and would be subject to freeze up during winter months. Active treatment plants for the entire flow would also generate huge volumes of U sludge requiring additional cost for disposal and creation of a p disposal area. Mine backfilling could be effective in reducing mine drain- ( age but was rejected due to many technical uncertainties dis cussed previously under the tailings section, including but not Q -102- n G P limited to effects on the hydrologic balance of the area, poten- L" tial for uncontrolled contaminated overflows at unknown locations GCl and preclusion of future mining potential. Because of the uncertainties of mine backfilling, it was not viewed as a perma LJ nent solution to the problem. 0 Biological treatment was rejected due to the potential destruction of large wetland areas and ancient peat bogs, Expe- J / rience with experimental peat bog systems shows that a large land area is required to allow efficient metals removal to take place, P p No action was considered unacceptable, as no enhancement P and possibly increased degredation of water quality and aquatic I • life could occur, P U 5,4 HYDROLOGIC SYSTEMS n Z 5,4.1 Selected Option I Habitat enhancement and fish stocking along the San Miguel ^ River and monitoring of surface and ground waters is the selected u option, A comprehensive monitoring and modeling program is pro posed for Red Mountain Creek or the Uncompahgre River, The esti mated costs of the San Miguel River remedial actions is $1,068,234 including surface and ground water monitoring. G 5.4.2 Rejected Options a. Stream sediment removal -103- GJ n b. No action (in the San Miguel River) c. Restocking c. Ground water treatment P 5.4.3 Selection Rationale LJ Habitat enhancement is the most cost-effective method of L restoring the resources once the sources of contaminants are con P u trolled. This action will provide an immediate improvement to the San Miguel River. With improvements to water quality and p stream habitat a diverse, abundant aquatic system will again exist in the San Miguel River. Restocking of the San Miguel River in the Telluride Valley was accepted since it will produce immediate improvement to the environment. Restocking of streams can be accomplished once water quality and habitat improvements occur. Ground water pumping and treatment was rejected due to n its marginal effectiveness and high cost. Implementation of L source control measures will reduce the metals loads to the n ground water system. Flushing of ground water through the valley will help to reduce metals levels in ground water and the subse quent contributions of metals to surface waters will decrease over time. Habitat enhancement was rejected for Red Mountain Creek and the Uncompahgre River. The steep gradients along the Uncompahgre U River from Red Mountain Creek to Ouray limit habitat necessary -104- p J L for a fishery in that area. Stream habitat improvements will not P change this situation. Stream sediment removal was rejected for the San Miguel River, the Uncompahgre River and Red Mountain Creek. Contami nated sediments will be removed over time as the streams flood. P Disturbance of the sediments during low flow periods for purposes u of removal would liberate large amounts of silt and metals. The P silt and metals would have deleterious effects on fish and other LJ aquatic life. Monitoring and modeling the effects of the source p J control remediation on the hydrologic systems was considered the r-i most cost-effective method. Monitoring also shows overall per- ^ formance of other remedial activities. P 5.5 SOILS 5.5.1 Selected Options L Removal, covering, treatment, sodding, mixing and no action P will be selectively employed based on soils concentrations and ^ location in the Telluride area. Institutional controls and reme G dial criteria will be established for future development. No action will be taken in the Red Mountain Creek Valley for soils away from the mill site and tailings piles. In addition a 5 year lead health effects study will be performed in Telluride. Resi dences on the Royer Gulch fan will be relocated. The cost of n this option is estimated to be $4,931,091 and the effectiveness u is near 100 percent in reducing human exposure to soils with high -105- n p L_ n L' p metals levels. p 5.5.2 Rejected Options Gl a. Removal with offsite disposal b. Removal with disposal in a lined RCRA impoundment P U c. Removal of all contaminated soil p d. No action for the Telluride Valley 5.5.3 Selection Rationale j Removal, covering, or treatment of soils with metals levels ul in excess of populated values in section 4.2.1.1 combined with U covering or treating of soils in excess of nonpopulated values in pj section 4.2.1.2: (1) is a reliable and effective means of n maintenance option; (3) causes minimal environmental disturbance L reducing human exposure to high metals levels; (2) is a low during implementation; and (4) is a permanent solution to reducing human exposure to contaminated soils. Establishment of criteria for soils remediation activities in future development will assure protection of growth areas in the valley. p U The use of optional remedial measures for soils allows flexibility in implementation and thus reduces disturbance in the community. At the same time human exposure is minimized and a permanent solution is achieved. Off-site disposal provides comparable reductions in expo sure at the site but was rejected due to the threat to public safety during transportation, the potential for releases during p L -106- u G p transportation and high costs. Removal with disposal in a lined impoundment provides marginally greater reduction of releases in r the long term but was rejected due to high cost and environmental disturbance during construction. Removal of all contaminated n soils was rejected due to the large amount of disturbance created p in the community, disruption to the community, the large cost involved and the lack of adequate space for disposal. No action I ; was deemed to be inadequate in light of the concerns expressed by LJ the ATSDR about lead levels in the soils. p 5.6 MILL SITE CLEANUP n 5.6.1 Selected Option JJ Confirmation testing that all PCB contaminated materials n and other materials subject to TSCA and RCRA requirements have been removed with disposal offsite, removal of soils with lead J levels in excess of 1000 mg/kg with disposal on tailings pile No. 4 on the Red Mountain side and on tailings piles Nos. 5 and 6 on LJ the Telluride side in the selected option. Disturbed areas would J also be reclaimed under this option. The cost of this option is _J $100,000 excluding soils which are covered under the soil P J section. This option would achieve near 100 percent reduction in human exposure to contaminants. -107- p U p 5.6.2 Rejected Options a. Removal with offsite disposal of all material L b. No action P _i 5.6.3 Selection Rationale J The selected option: (1) is reliable and effective in n reducing exposure to metals and organic as well as precluding the uJ risks of future releases to the environment; (2) is a low mainte- P nance option; (3) causes minimal environmental disturbance during _i implementation; and (4) is a permanent solution to the problem. P J Although removal offsite may provide a minimally higher p-, safeguard for releases from all materials present, it was reject- J-* ed due to large environmental disturbance during implementation, Z the potential for releasing hazardous substances during removal, and extreme cost. No action was rejected because it did not reduce releases or exposure. D L 5.7 TELLURIDE VALLEY L The costs of the selected options are presented in Table n 5.1. Total cost of remediation is $20,588,991. The effective ness of overall remediation on the San Miguel River is discussed in Section 5.11. -108- p 5.8 HIGH COUNTRY J The costs of the selected options are presented in Table U 5.2. Total cost of remediation is $4,409,612. The effectiveness p of overall remediation on the San Miguel River is discussed below in Section 5.11. 5.9 RED MOUNTAIN CREEK AND UNCOMPAHGRE VALLEYS The costs of the selected options are presented in Table L 5.3. Total cost of remediation is $24,248,291. The effective- p ness of overall remediation on Red Mountain Creek and the Uncompahgre River is discussed in section 5.10. G • • . 5.10 EFFECTIVENESS OF THE RED MOUNTAIN DISTRICT REMEDIAL ACTIONS The effectiveness of the remedial action selected for the I Red Mountain Mining District is estimated to be 95 percent removal of metals and is based on data and analysis contained in J the RI/FS reports prepared for the State of Colorado. Table 5.5 p shows the cost effectiveness for the alternatives in the feasi bility study. The basic approach to improving water quality of Pj the hydrologic system downstream of the site is to enhance and accelerate natural mechanisms for removing and stabilizing con- U taminants in the upper portion of Red Mountain Creek. The extent C to which the releases of contaminants continue to migrate from -109- P the site and the degree to which water quality improvements are ^ realized in Red Mountain Creek and the Uncompahgre River will Cl depend upon the effectiveness of several critical components pre- u sented in this Remedial Action Plan. L Data from the remedial investigation (RI, 1986) showed that P heavy metal removal in Red Mountain Creek and the Uncompahgre '-' River closely paralleled the observed loss of iron from the water C column. The improvement in water quality, from the extremely poor conditions in Red Mountain Creek and the Uncompahgre River L around Ouray, which was observed near Ridgway is most likely the P result of iron and aluminimn precipitation and the subsequent absorption or coprecipitation of toxic metals. The remedies se- ~1 lected for this mining district were selected to take advantage U of this natural cleansing and to promote its occurence much Z closer to the site. The remedies should encourage continued p oxidation of ferrous ion to ferric ion, promote precipitation of both iron and aluminum through pH adjustments (optimum range 6.5 P to 8.5), and permit sufficient time for chemical interactions and sedimentation. L The major components of the Remedial Action Plan which G achieve the conditions which promote chemical precipitation include the diversion of mine water from above the 1200 level to provide some neutralization of the acidic waters in Red Mountain Creek, installation of limestone barriers along Commodore Gulch -110- and in Red Mountain Creek. The chemistry of the diverted water, including the neutralizing capacity (alkalinity) and the comple Q ment of metals which would also be diverted, would need to be better defined than presently possible to fully evaluate the net benefit to clean up of Red Mountain Creek. To achieve effective removal of precipitated iron, aluminum and associated metals, the mainstem reservoir on Red Mountain Creek has been sized to provide an average detention time of around 20 days. The reservoir would be located in the area of Ironton Park just below tailing pile No. 4 and would operate to remove both point and nonpoint loadings into Red Mountain Creek L with the same efficiency. Calculations have indicated that such a reservoir would have a removal efficiency for iron in the range of 95 percent - 99 percent, in general. It is noted that during peak spring runoff the efficiency will be reduced to 50 percent for a 1 - 2 week interval because of the reduced sedimentation time. Assuming that the pH has been effectively increased through mixing of Treasury Tunnel water with Red Mountain Creek and by limestone charging to 6.5 or greater, a similar percent reduction of Cu, Pb, Cd and Zn should also be realized. Prior to the diversion of any mine waters and before the design of the limestone barriers, it will be essential to perform bench and pilot scale studies to confirm that the appropriate chemical con ditions can be established within the environment created by the pl G -111- u p, above remedial components. -J Based on the modeling which was performed for alternative 4 Pj in the feasibility study (FS, 1986) and the present components in L the Remedial Action Plan, the water quality of the discharge from the reservoir would meet existing water quality standards for the \^ i „ Uncompahgre River (segment below Red Mountain Creek) at a removal LJ efficiency of 95 percent. This efficiency would be met during P the major part of the year. In all likelihood, the existing L Uncompahgre River water quality standards for Pb and Cd would L also be met at the reservoir outlet. Existing stream standards j—I . for lead and copper are not fully protective of aquatic life so L^ the state has included relevant and appropriate standards as P goals for the remedial action in Table 5.6. The outlet water quality has been compared to the Uncompahgre River water quality L standards for two reasons, firsit, there are no metal standards G for Red Mountain Creek and second, the mixing of Red Mountain Creek with the Uncompahgre River is the major reason why water quality in the Uncompahgre River violates the standards for Zn and Cu at least as far downstream as Ridgway. It is also important to examine the resulting water quality from mixing Red Mountain Creek (after the reservoir)^ the Uncompahgre River (above Red Mountain Creek) and Canyon Creek at the Town of Ouray. These calculations are based on a set of samples taken during May 1985, by the state's consultants. Fur- G -112- thermore, flow measurements were assumed to be equal volumes for each of the major flow streams for comparison purposes, based on field observation. The results shown in Table 5.6 indicate major improvements in the Uncompahgre River including the restoration of water quality to below existing standards for Cu, Pb, Cd and Zn. Further attenuation of the metal concentrations below Ouray will occur but it is not possible to estimate the improvement without additional modeling of contaminant transport and fate. The above estimates of effectiveness assume that other com ponents of the Remedial Action Plan prevent increases in the loadings to Red Mountain Creek above the present estimates. The remedial actions proposed for the tailings, waste rock and mine n waters are necessary to remove as much metal loading as feasible _ to ensure success of this approach for reducing contaminant y transport and restoring water quality in the Uncompahgre River to p-) meet relevant and appropriate stream standards. ^ Implementation of the technologies selected for the remedy P shall be maximized to achieve the greatest water quality improve ments possible using such technologies to achieve or exceed y applicable, relevent or appropriate goals. — L 5.11 EFFECTIVENESS OF THE TELLURIDE DISTRICT REMEDIAL ACTIONS P LJ The effectiveness of the remedial action selected for the p Telluride Mining District was based on data and analysis con- J p tained in the RI/FS reports prepared for the State of Colorado. The basic approach to improving water quality of the hydrologic ~l system downstream of the site is a major reduction of metal —I loadings due to mine waters, tailings pile seepage, erosion of L tailings and subsequent dissolution, waste rock dissolution, and p accrual of contaminated ground water. The extent to which the releases of contaminants continue .to migrate from the site and LJ the degree to which water quality improvements are realized in the San Miguel River will depend upon the effectiveness of several critical components presented in this Remedial Action Plan. Water quality in the San Miguel River presently exceeds the water quality standards which have been set for this segment of the river as well as the more stringent Colorado Basic Standards incorporated herein. The majority of the metal loadings occur in the segment of the river near the infiltration lagoons, at Marshall Creek, and along tailing piles No. 3, No. 4 and No. 6. A certain percentage of the loadings may be associated with accrual of contaminated ground water. The effectiveness of the Remedial Action Plan will depend on the efficiency by which the n loadings associated with these sources are reduced. Segregation of mine waters above the 1200 level and passive geochemical treatment of the remaining mine waters will reduce the impact of the infiltration lagoons and subsurface migration -114- p of mine waters to the San Miguel River. The overall efficiency will be a function of the amount and quality of mine water which ! can be diverted to the Red Mountain Mining District and the degree to which flows into the mine can be reduced. The L geochemical treatment will be located at the Royer Gulch alluvial p fan. This passive treatment methodology is presently believed to be highly effective at reducing metal levels in the mine water. The overall efficiency has been estimated at 90 percent - 98 per P cent removal. In the event that the passive treatment system LJ will not adequately treat the mine waters, the Remedial Action n Plan provides for the addition of active treatment. L The next major source of loading is Marshall Creek. The load reduction possible through remedies applied in the high n country and along the main stem of Marshall Creek carries the LJ greatest uncertainty and has been estimated at 75 percent - 97 p percent. Removal of tailing piles No. 1 - No. 4 and cleanup of underlying materials and waste rock should reduce loadings from I these sources by at least 95 percent. The remedies applied to n tailing piles No. 5 and No. 6 should be effective but not as LJ effective as complete removal. For calculation purposes, the p load reduction has been estimated at 85 percent. Data from the RI/FS process indicated substantial loadings along the tailing ] piles. Depending upon whether the loading was due to seepage, ground water accrual from upstream sources (mine waters, infil- Q -115- u G P tration lagoons, etc.), or erosion and dissolution of tailings p within the stream, the efficiency of the remedy in reducing these P loadings has been estimated at 75 percent - 95 percent for calcu- lations. Removal of streamside tailings or isolation of tailings —' and waste rock along the river has been estimated to reduce loads p to the river by 95 percent. L Using the above reduction efficiencies and the mass loading P y analysis conducted for the RI, the effectiveness of the Remedial P Action Plan for improving San Miguel water quality was evaluated. L-^ Because a range of efficiencies was evaluated, the effectiveness P of the remediation also contains some uncertainty. The effec- L tiveness is based on the improvement in the river with respect to y existing stream standards as well as the Colorado Basic Standards P incorporated herein. The calculations of metals concentrations LJ are shown in Table 5.7. Assuming the mid-range removal effi- P ciency for certain remedial components, the concentrations metals shown in Table 5.7 below the confluence with Bear Creek are all GJ significantly reduced by the remedial action. The calculations P indicate that lead and copper values will be consistently below L the Colorado Basic Standard. Additionally, zinc concentrations P are likely to meet or exceed the standard during some parts of the year. The effectiveness will be highly dependent upon the Un I success of the high country remedies and the mine water treatment scenarios. -116- p Water quality in the lower segment of the San Miguel River below the confluence with the South Fork will likely be improved j with respect to the segment zinc standard of 0.10 mg/l and it would be very probable that the standard would not be exceeded. P LJ Water quality for the other metals would most likely parallel p improvements observed for zinc, in general. Water quality data do not permit a detailed analysis for these metals and, for this reason, water quality improvement was estimated using the per centage improvement observed for zinc. *** 0 p L -117- u 1 of 8 TABLE 5.1 COST SUMMARY TELLURIDE DISTRICT ESTIMATED COST 1986 DOLLARS TAILINGS PILES Consolidate piles 1-4 onto piles 5 & 6 (includes cost of revegetation) CAPITAL COST $2,351,013 PRESENT WORTH COST (YR 1) $2,132,609 0 AND M* $0 ENVR. MON. @ 1 % OF PW $21,326 P CONTINGENCY § 10 % OF PW $213,261 u ENGINEERING @ 2 % OF PW $42,652 TOTAL $2,409,848 u 1 Consolidate misc. tails along river onto piles 5 & 6 LJ (includes revegetation cost) CAPITAL COST $352,080 PRESENT WORTH COST (YR 1) $320,073 0 AND M* $0 ENVR. MON. § 1 % OF PW $3,201 CONTINGENCY § 20 % OF PW $64,015 ENGINEERING § 2 % OF PW $6,401 p TOTAL $393,690 u Consolidate tails at Society Turn into impoundment (includes revegetation cost) CAPITAL COST $688,902 PRESENT WORTH COST (YR 1) $626,275 0 AND M* $0 ENVR. MON. @ 1 % OF PW $6,263 CONTINGENCY § 20 % OF PW $125,255 ENGINEERING @ 2 % OF PW $12,526 TOTAL $770,319 p * PRESENT WORTH COST L 2 of 8 Construct impoundment near Society Turn CAPITAL COST $1,540,286 PRESENT WORTH COST (YR 1) $1,400,260 0 AND M* $71,030 ENVR. MON. @ 1 % OF PW $14,713 CONTINGENCY § 20 % OF PW $294,258 ENGINEERING @2%0FPW $29,426 TOTAL $1,809,687 p Cap piles 5 & 6 with 4• thick cap and 2' thick low ( permeability layer (includes revegetation and flood ^ protection cost) CAPITAL COST $5,496,077 PRESENT WORTH COST (YRS 1&2) $4,687,379 0 AND M* (YRS 2-30 $128,277 ENVR. MON. e 1 % OF PW $48,157 I CONTINGENCY @ 20 % OF PW $963,131 ^ ENGINEERING © 15 % OF PW $722,348 TOTAL $6,549,292 Drainage control (runon diversion) CAPITAL COST $200,077 PRESENT WORTH COST (YRS 1) $181,889 O AND M* (YRS 2-30) $71,030 ENVR. MON. @ 1 % OF PW $2,529 CONTINGENCY @ 20 % OF PW $50,584 ENGINEERING e 15 % OF PW $37,938 TOTAL $343,970 ESTIMATED TOTAL - TAILINGS PILES $12,276,806 P u * PRESENT WORTH COST 0 p U 3 of 8 WASTE PILES Drainage control (runon diversion of Mill and Meldrum waste piles) CAPITAL COST $33 ,594 PRESENT WORTH COST (YR 1) $30 ,539 0 AND M* $0 ENVR. MON. § 1 % OF PW ?305 CONTINGENCY § 20 % OF PW $6 ,108 ENGINEERING § 15 % OF PW $4 ,581 TOTAL $41,533 Q P Remove from stream U covered under consolidation of misc. tails n Sediment collection pond at base of Marshall Creek CAPITAL COST $520,522 PRESENT WORTH COST (YR 1) $430,208 0 AND M* $124,264 ENVR. MON. § 1 % OF PW $5,545 CONTINGENCY § 20 % OF PW $110,894 ENGINEERING § 15 % OF PW $83,171 TOTAL $754,082 ESTIMATED TOTAL - WASTE PILES $795,615 SOILS Offsite soils: remove soils with cone. >1000 ppm Pb CAPITAL COST $1,522,483 U PRESENT WORTH COST (YRS 1) $1,384,074 0 AND M* (YRS 2-30) . $0 p ENVR. MON. § 1 % OF PW $13,841 I CONTINGENCY § 20 % OF PW $276,815 ^ ENGINEERING @ 2 % OF PW $27,681 TOTAL $1,702,411 * PRESENT WORTH COST Un 4 of 8 Offsite soils: cover soils with cone, from 500 to 1000 ppm Pb „ CAPITAL COST $66,867 / PRESENT WORTH COST (YRS 1) $60,789 0 AND M* (YRS 2-30) $0 ENVR. MON. @ 1 % OF PW $608 CONTINGENCY @ 20 % OF PW $12,158 ENGINEERING §2%0FPW $1,216 LJ TOTAL $74,771 G Onsite soils; remove soils with cone. >1000 ppm Pb LJ and consolidate onto piles 5 & 6 CAPITAL COST $431,255 r- PRESENT WORTH COST (YR 1) $392,050 0 AND M* (YRS 2-30) $0 ENVR. MON. § 1 % OF PW $3,921 n CONTINGENCY @ 20 % OF PW $78,410 ENGINEERING @ 2 % OF PW $7,841 TOTAL $482,222 u Onsite soils: cover soils with cone, from 500 to 1000 ppm Pb KJ CAPITAL COST $386,777 PRESENT WORTH COST (YRS 1) $351,615 O AND M* (YRS 2-30) $0 ENVR. MON. e 1 % OF PW $3,516 CONTINGENCY § 20 % OF PW $70,323 ENGINEERING @ 2 % OF PW $7,032 0 TOTAL $432,486 p Health effects study of Telluride residents CAPITAL COST $1,650,000 PRESENT WORTH COST (YRS 1-5) $1,250,960 O AND M* $0 CONTINGENCY @ 20 % OF PW $250,192 ENGINEERING e 2 % OF PW $25,019 TOTAL $1,526,171 * PRESENT WORTH COST G 5 of 8 Relocate residents of Pandora trailer park CAPITAL COST $700,000 PRESENT WORTH COST (YR 1) $636,634 G 0 AND M* $0 CONTINGENCY @ 10 % OF PW $63,663 ENGINEERING @ 2 % OF PW $12,733 TOTAL $713,030 P ESTIMATED TOTAL - SOILS $4,931,091 n LJ MILLSITE WASTE Geochemical study to evaluate Pandora Mill site elean-up TOTAL $50,000 P ESTIMATED TOTAL - MILLSITE WASTE $50,000 MINE PORTALS PLUG/DIVERT INFILTRATION POINTS ^ SEE HIGH COUNTRY q P Control and reroute mine flows (10 bulk heads) ri CAPITAL COST $313,450 P PRESENT WORTH COST (YRS 1) $284,955 O AND M* (YRS 2-30) $0 ENVR. MON. e 1 % OF PW $2,850 CONTINGENCY @ 20 % OF PW $56,991 GJ ENGINEERING @ 15 % OF PW $42,743 p TOTAL $387,539 * PRESENT WORTH COST 6 of 8 \ / Divert mine water above 1200 level to Treasury Tunnel ^ (12 bulk heads) P CAPITAL COST $375,600 P PRESENT WORTH COST (YRS 1) $341,455 0 AND M* (YRS 2-30) $62,837 ENVR. MON. § 1 % OF PW $4,043 CONTINGENCY @ 20 % OF PW $80,858 u ENGINEERING @ 15 % OF PW $60,644 P TOTAL $549,837 ', I Construct infiltration lagoons on Royer Gulch fan (8900 gpm capacity) P CAPITAL COST $500,910 P PRESENT WORTH COST (YRS 1) $455,372 O AND M* (YRS 2-30) $76,045 ENVR. MON, @ 1 % OF PW $5,314 CONTINGENCY @ 20 % OF PW $106,283 ENGINEERING @ 15 % OF PW $79,713 n . TOTAL $722,727 u CONTINGENT REMEDY Construct mine water treatment plant to handle 1 mgd CAPITAL COST $682,969 PRESENT WORTH COST (YRS 1) $320,186 0 AND M* (YRS 2-30) $755,775 GG ENVR, MON, § 1 % OF PW $10,760 CONTINGENCY @ 20 % OF PW $215,192 ENGINEERING @ 15 % OF PW $161,394 TOTAL $1,463,307 GG ESTIMATED TOTAL - OF MINE PORTALS $1,660,103 U (does not include active treatment plant cost) Z * PRESENT WORTH COST G 7 of 8 y SAN MIGUEL RIVER HYDROLOGIC SYSTEM Habitat enhancement (Marshall Creek to Society Turn) CAPITAL COST $138,369 PRESENT WORTH COST (YR 2) $114,354 0 AND M* (YR 2) $0 ENVR, MON. § 1 % OF PW $1,144 Q CONTINGENCY e 20 % OF PW $22,871 ENGINEERING § 15 % OF PW $17,153 TOTAL $155,522 Stock fish (Marshall Creek to Society Turn) CAPITAL COST $31,800 PRESENT WORTH COST (YR 2-4) $23,964 0 AND M* $0 ENVR. MON. § 1 % OF PW $240 CONTINGENCY @20%OFPW $4,793 O ENGINEERING § 15 % OF PW $3,595 TOTAL $32,592 Remove selected sediment See consolidation of misc. tails ESTIMATED TOTAL - SAN MIGUEL HYDROLOGIC SYSTEM $188,114 GJ MONITORING Ground water monitoring (9 wells -- includes install CAPITAL COST $27,800 PRESENT WORTH (YR 1) $25,273 U MONITORING* (YRS 1-5) $170,585 MONITORING* (YRS 6-10) $17,653 n PUMPS* (YR 5) $7,448 ENVR. MON. @ 1 % OF PW $2,210 p ENGINEERING § 20 % OF PW $44,192 ENGINEERING § 15 % OF PW $33,144 TOTAL $300,505 Q * PRESENT WORTH COST 8 of 8 Surface water monitoring (10 station) CAPITAL COST $0,00 P MONITORING* (YRS 1-5) $113,724 y MONITORING* (YRS 6-10) $11,769 CONTINGENCY § 20 % $25,099 ENGINEERING @ 15 % $18,824 TOTAL $169,416 Monitoring of fish populations (4 stations) CAPITAL COST $0,00 MONITORING* (YRS 1-10) $160,993 CONTINGENCY § 20 % $32,199 P ENGINEERING § 15 % $24,149 TOTAL $217,341 P ESTIMATED TOTAL - MONITORING $687,262 TOTAL ESTIMATED COST OF TELLURIDE VALLEY ACTIVITIES $20,588,991 (Does Not Include Contingent Treatment Plant Cost) D * PRESENT WORTH COST 1 of 2 y TABLE 5,2 HIGH COUNTRY REMEDIAL ACTIVITIES Q ESTIMATED COST p IN 1986 DOLLARS ^ TAILINGS AND WASTE PILES P Remove tails/waste material from stream CAPITAL COST $45 ,705 p PRESENT WORTH COST (YR 3) $34 ,338 I 0 AND M* $0 ^ ENVR, MON. § 1 % OF PW ?343 ^ CONTINGENCY @ 20 % OF PW $6 ,868 G ENGINEERING e 10 % OF PW P $3 ,434 TOTAL $44,983 Z Runon control I CAPITAL COST $35,215 U PRESENT WORTH COST (YR 3) $26,458 0 AND M* (COVERED UNDER: DIVERT POTENTIAL p INFILTRATION POINTS) 1 ENVR. MON. @ 1 % OF PW $265 CONTINGENCY @ 20 % OF PW $5,292 P ENGINEERING @10%OFPW $2,646 TOTAL $34,661 ESTIMATED TOTAL - TAILINGS AND WASTE PILES $79,644 •ur \ MINE PORTALS Ul- Plug selected portals (5 portals) CAPITAL COST $156,725 PRESENT WORTH COST (YRS 1-3) $129,917 0 AND M* $0 ENVR. MON. § 1 % OF PW $1,299 CONTINGENCY @ 20 % OF PW $25,983 ENGINEERING @ 15 % OF PW $19,488 n TOTAL $176,687 * PRESENT WORTH COST 2 of 2 Divert Discharge around waste piles at portals (23 portals) CAPITAL COST $104,513 PRESENT WORTH COST (YRS 1-3) $86,636 LJ O AND M* $0 ENVR. MON. e 1 % OF PW $866 CONTINGENCY @ 20 % OF PW $17,327 ENGINEERING @ 10 % OF PW $8,664 TOTAL $113,493 L ESTIMATED TOTAL - MINE PORTALS $290,180 n u INFILTRATION CONTROL -J Plug infiltration points P CAPITAL COST $2,993,086 ij PRESENT WORTH COST (YRS 1-3) $2,481,121 0 AND M* $0 n ENVR. MON. @ 1 % OF PW $24,811 L CONTINGENCY @ 30 % OF PW $744,336 ENGINEERING @ 15 % OF PW $372,168 TOTAL $3,622,436 Divert potential infiltration points CAPITAL COST $159,272 PRESENT WORTH COST (YRS 1-3) $132,029 0 AND M* (YRS 2-30) $153,828 ENVR. MON. @ 1 % OF PW $2,859 CONTINGENCY @ 30 % OF PW $85,757 ENGINEERING § 15 % OF PW $42,879 p P TOTAL $417,352 ESTIMATED TOTAL - INFILTRATION CONTROL $4,039,788 TOTAL ESTIMATED COST OF HIGH COUNTRY REMEDIAL ACTIVITIES $4,409,612 u Q * PRESENT WORTH COST 1 of 4 P u TABLE 5.3 RED MOUNTAIN REMEDIAL ACTIVITIES ESTIMATED COST IN 1986 DOLLARS TAILINGS PILES Consolidation of Piles 1-3, Buried pile and misc. tails onto Pile 4 (includes revegetation cost) P CAPITAL COST $4,399,866 U PRESENT WORTH COST (YR 1) $3,999,910 f\0 TfVTTtAND UTibM* &$ 0rt ENVR. MON. @ 1 % OF PW $39,999 P CONTINGENCY @ 20 % OF PW $799,982 ENGINEERING @2%0FPW $79,998 GG TOTAL $4,919,889 Cap Pile 4 (includes revegetation and flood protection cost) CAPITAL COST $3,543,697 PRESENT WORTH COST (YRS 1-2) $2,788,156 0 AND M* (YRS 3-30) $128,277 ENVR. MON. § 1 % OF PW $29,164 CONTINGENCY @ 20 % OF PW $583,287 ENGINEERING e 10 % OF PW $291,643 TOTAL $3,820,527 Pile 4 drainage control (runon diversion) CAPITAL COST $149,532 PRESENT WORTH COST (YR 1) $135,938 U 0 AND M* (YRS 2-30) $53,885 ENVR. MON. § 1 % OF PW $1,898 CONTINGENCY 6 20 % OF PW $37,965 ENGINEERING § 10 % OF PW $18,982 TOTAL $248,668 U ESTIMATED TOTAL - TAILINGS PILES $8,989,084 * PRESENT WORTH COST 2 of 4 y WASTE PILES p Remove from stream LJ CAPITAL COST $55 ,000 PRESENT WORTH COST (YR 1) $50 ,000 $0 J O AND M* i J ENVR. MON. § 1 % OF PW ?500 CONTINGENCY § 20 % OF PW $10 ,000 p ENGINEERING § 15 % OF PW $7 ,500 L TOTAL $68,000 L Divert discharge around waste pile in yard area (1350' of shotcrete lined ditch) p CAPITAL COST $90,549 LJ PRESENT WORTH COST (YR 1) $82,317 0 AND M* (YRS 2-30) $33,806 P ENVR. MON. § 1 % OF PW $1,161 P CONTINGENCY @ 20 % OF PW $23,225 ENGINEERING § 10 % OF PW $11,612 P TOTAL $152,121 Divert Discharge around misc. piles (40,000' of unlined ditch) CAPITAL COST $40,748 PRESENT WORTH (YR 1) $37,044 0 AND M* (YRS 2-30) $33,806 ENVR. MON. § 1 % OF PW $709 CONTINGENCY § 20 % OF PW $14,170 ENGINEERING 6 10 % OF PW $7,085 TOTAL $92,814 ESTIMATED TOTAL - WASTE PILES $312,935 MILLSITE WASTE Study to evaluated mill site clean-up TOTAL $50,000 ESTIMATED TOTAL - MILLSITE WASTE $50,000 * PRESENT WORTH COST 3 of 4 MINE PORTALS P Divert discharge around waste piles CAPITAL COST $46,810 PRESENT WORTH COST (YRS 1-3) $38,803 0 AND M* $0 ENVR. MON. @ 1 % OF PW $388 CONTINGENCY § 20 % OF PW $7,761 ENGINEERING § 10 % OF PW $3,880 TOTAL $50,832 Construct below-grade reservoir in Ironton Park (2000 acre-foot capacity) U CAPITAL COST $14,137,733 PRESENT WORTH COST (YRS 2-3) $11,400,375 P O AND M* (YRS 3-30) $0 J ENVR. MON, § 1 % OF PW $114,004 CONTINGENCY @ 20 % OF PW $2,280,075 ENGINEERING § 5 % OF PW $570,019 TOTAL $14,364,473 Limestone charging of Commodore Gulch and Red Mountain Creek CAPITAL COST $176,250 PRESENT WORTH COST (YR 1) $160,227 0 AND M* (2-30) $51,618 ENVR, MON. § % OF PW $2,118 P CONTINGENCY § 20 % OF PW $42,369 ENGINEERING @ 15 % OF PW $31,777 p P TOTAL $288,109 G ESTIMATED TOTAL - MINE PORTALS $14,703,414 G * PRESENT WORTH COST 4 of 4 MONITORING C\ Ground water monitoring: 4 wells (includes well installation Z cost) CAPITAL COST $11,120 PRESENT WORTH COST (YR 1) $10,109 MONITORING* (YRS 1-5) $45,490 MONITORING* (YRS 6-10) $4,708 0 AND M* (YR 5) $3,715 y CONTINGENCY @ 20 % $12,804 ENGINEERING @10% $6,402 TOTAL $83,228 Surface water monitoring (7 stations) MONITORING* (YRS 1-5) $76,422 MONITORING* (YRS 6-10) $7,909 P CONTINGENCY § 20 % $16,866 ENGINEERING @10% $8,433 TOTAL $109,630 ESTIMATED TOTAL - MONITORING $192,858 TOTAL ESTIMATED COST OF RED MOUNTAIN CREEK REMEDIAL ACTIVITIES $24,248,291 Gl L TOTAL ESTIMATED COST OF ALL REMEDIAL ACTIVITIES $49,246,894 (Does Not Include Treatment Plant Cost) * PRESENT WORTH COST TABLE 5.4 Cost and Effectiveness for Feasibility Study Alternatives n P TELLURIDE VALLEY ALTERNATIVE Cost EFFECTIVENESS* P 1 $ 2,248,677,000 98 percent 2 $ 197,573,000 95 percent 3 $ 162,353,000 to 89 percent $ 171,899,000 $ 99,269,000 to 76 percent P $ 108,815,000 5 $ 199,254,000 64 percent 6 -0- 0 percent * Based on percent reduction in zinc concentrations in the San Miguel River; Table 5.1-8 Idarado Feasibility Study U -118- TABLE 5.5 Cost and Effectiveness for Feasibility Study Alternatives RED MOUNTAIN CREEK P U ALTERNATIVE Cost EFFECTIVENESS* $ 1,022,714,000 LJ to $ 1,050,374,OaO 98 percent P P $ 159,141,000 to $ 186,801,000 98 percent $ 121,917,000 to $ 149,577,000 99 percent $ 53,745,000 to 97 percent $ 81,405,000 5 $ 22,528,000 46 percent 6 -0- 0 percent P u * Based on zinc reductions in Red Mountain Creek with 95 percent control of nonpoint sources; Tables 8.1-8 through 8.1-11 Feasibility Study of Idarado site. -119- TABLE 5.6 Water Quality Near the Town of Ouray (mg/l) Uncompahgre Water Quality Water Quality of Tributaries Below Canyon Creek RM02 UR06 CYOl PERCENT METAL BEFORE* AFTER* BEFORE* AFTER* IMPVM'T Fe 20.0 1.00 0.43 0.91 7.11 0.78 89,0 Zn 1.07 0.054 0.21 0.091 0.457 0.118 74,2 Cu 0.38 0.019 0.034 0.008 0.140 0.020 85,7 U Al 5.3 0.265 0.21 0.94 2.15 0.472 78,0 Pb 0.10 0.005 0.028 0.07 0.066 0,034 48,5 L Cd 0.004 0.0002 0.001 0.0009 0.0020 0,0007 65,0 G The above conditions represent the water quality of Red Mountain Creek under the Remedial Action Plan outlined in this document. Surface Water Standards (mg/l) Zn 0,15** Q Cu 0,005*** Pb 0,004*** Cd 0,0004 * Water quality before the remedial action and after remedial actions, ** Relevant and appropriate standard from Colorado Division of Wildlife *** Relevant and appropriate Colorado Basic Standards RM02 - Red Mountain Creek below Ironton Park -120- G UR06 - Uncompahgre River above confluence with Red Mountain Creek CYOl - Canyon Creek above confluence with the Uncompahgre River These sample locations are further described in the state's Reme dial Investigation, TABLE 5,7 P U Estimates of Concentrations of Zinc and Cadmium in the San Miguel River Below Its Confluence with Bear Creek Resulting from Implementation of Remedial Action Plan Water Quality Achieved Concentration Standards mg/l Range of Values, mg/l Zinc 0,15* 0,1 - 0.4 Cadmium 0,0004 •* 001 Lead ,004** * 003 Copper 0,005 " 005 * Relevant and appropriate standard from Colorado Division of Wildlife ** Relevant and appropriate Colorado Basic standard 6.0 COMMUNITY RELATIONS ACTIVITIES 6.1 THE REMEDIAL INVESTIGATION/FEASIBILITY STUDY PROCESS The state has undertaken a community relations program with -121- units of local government and local residents during the course of the Remedial Investigation and Feasibility Study process n (RI/FS). Early in 1985, a Community Relations Plan (the "Plan") was drafted based upon EPA guidelines. The Plan, attached as ROD JJ Appendix A, has been revised and updated as necessary. P Pursuant to the Plan, the state conducted several meetings with representatives of municipal and county governmental bodies, J environmental groups and interested individuals to keep them P informed and to receive input about local concerns. Addition- LJ ally, other communications have taken place between state repre- P sentatives and these groups and individuals to keep them advised of the status of the case and to respond to their concerns. L On April 13, 1986, the state published its Remedial Inves- P tigation report. On May 21, 1986, the report was sent to the LJ federal Agency for Toxic Substances and Disease Registry C ("ATSDR") to assess any health risks involved with the contamina tion from the Idarado Mine. L On June 28, the state published its Feasibility Study P report listing six alternatives for each district to clean up the LJ contamination at the site. The reports were made available at Pp Telluride Town Hall, San Miguel Public Library, Ouray Town Hall, Ouray Public Library, Mesa County Library, Montrose Regional y Library and the Department of Health, for access by local resi- p. dents, 0 -122- 0 p On July 28 and 29, 1986, the state held public meetings in Telluride and Ouray, respectively. The meetings were attended by P approximately 150 people and approximately 40 people gave verbal comments, Mr, Michael McGeehin, regional representative for the P ATSDR reported to the town the conclusions of the health risk assessment conducted by that agency. The ATSDR recommended that J the state conduct a soils survey for lead in the Town of n Telluride based upon the levels found in a study performed in 1977 and the state's Remedial Investigation. The state conducted the study in August-September, and held two more public meetings n on October 14 and 15, 1986, informing the public of the results u of the soils survey and answering questions. Over 100 people P attended these meetings and approximately thirty-five people gave verbal comments. Based upon the results of the soils survey a J-* sampling program for blood lead levels was conducted in Telluride y jointly by the defendants and the state. (The state has not yet received all of the results of the study.) P y A public comment period commenced on June 30, 1986, and continued through October 31, 1986. Notices of the comment 0 period, the release of the RI/FS, and the public meetings were sent to public officials, interested citizens and local and regional media. In addition to the verbal comments received at public meet ings, approximately sixty-five written comments were received by -123- the Department of Health. The comments formally submitted either at the public meetings or in writing were considered in the se lection of the remedial actions and are responded to herein. Many of the letters received contained the same or similar com ments. In an effort to avoid redundancy, similar comments will be addressed with a single response. The coimnents to the state's investigations and studies are divisible between general site comments, and comments specifi cally directed at the Telluride or Ouray District. The state's response to the comments will first address general comments, then comments from the Telluride and Red Mountain Districts, respectively. 6.1.1. General (Entire Site) Comment: Several individuals recognized the contribution of the mining industry in the area, but also noted that the unforeseen health and environmental problems caused by mining activities must be addressed. These individuals developed 12 objectives to ensure a safe and healthy environment for present populations and future generations. These objectives included: 1) ensuring that existing and future water supplies for the town meet minimum standards; 2) ensuring that adverse synergistic effects of all contaminants are remediated to an extent that pro- -124- p, p P teets human health and the environment; 3) ensuring that ground u and surface water meet water quality standards capable of sup- porting aquatic life; 4) ensuring that air quality meet minimum state and federal standards; 5) ensuring that soils in the town G . . L. meet the standard of 500 parts per million for lead and maximum p safe standards for other contaminants; 6) ensuring that contami nant sources be remediated to withstand a probable maximum flood; p y 7) ensuring that the remediation be conducted in a manner that will cause the least disruption to the life and commerce of the P citizens in the area; 8) ensuring that remediation will not fur- p ther degrade the natural resources in the area; 9) ensuring that the remediation include long term monitoring; 10) ensuring that I j any negotiated settlement meet acceptable health, safety and environmental standards; 11) ensuring that the town collect past U and future response costs and damages; and 12) ensuring that the p implementation of any remedy be conducted to meet environmental quality standards. They also requested that whenever possible, p I solutions should be permanent and accomplished in a timely man- ner. 0 These individuals rejected alternatives 5 (direct revegetation) and 6 (no action) as being deficient in their entirety. They commented that plugging of the glory holes should not be considered unless methods are designed which have minimal n impact on the High Country, including the Tomboy Mine Ruins, -125- U They supported a water treatment plant for mine surface flows or transmountain diversion pending protection of existing water rights on the San Miguel River, They supported off-site disposal or again, a pilot program for backfilling the mine. These individuals supported cleanup of the mine yard area, removal and replacement of Telluride's soils containing lead in excess of 500 parts per million, and soils and environmental testing be conducted west of the Town of Telluride. Finally, they requested the state to consider ongoing monitoring, estab lishing a fund to secure against anticipated failures, and com pensating Telluride for response costs and damages. Response: The state has attempted in the selection of the remedial action plan to be consistent with the above goals. Implementation of the remedial actions on site will also be undertaken consistent with these goals. With regard to these specific comments, the state has LJ rejected alternatives 5 and 6 for the tailings piles for reasons stated in this ROD, Further, the state has rejected alternative 6 for source control. Q Environmental disruption associated with mine inflow diver sion was considered. Such activities can be performed in an en vironmentally acceptable manner with little or no disruption to the High Country Area or to the Tomboy ruins. The state will employ measures to minimize impacts to historically valuable -126- 0 sites. As discussed previously, off-site disposal of tailings and backfilling of the mine with tailings were not considered to be cost-effective or permanent solutions to the problem. Soils cleanup in the Town of Telluride is based on the concern level of 500 ppm lead voiced by ATSDR and the Town of Telluride, However, because of the volumes of materials involved, only soils with lead levels in excess of 1000 ppm shall be removed. Soils with lead levels in excess of 500 ppm but less than 1000 ppm shall be p remediated to reduce human exposure. Finally, the state is in agreement with the comments regarding Mill Yard cleanup and ongoing monitoring. The state, as trustee for natural resources, is entitled to damages for public interests in the natural resources pursuant to CERCLA, The state's trusteeship under CERCLA does not provide for recovery of private interests in the natural resources. Any damages collected by the state are required by state statute to go into the state's CERCLA Recovery Fund. It would be up to the Colorado Legislature to compensate the Town of Telluride for any U damages it has suffered. The state has, however, preauthorized the town for eligible response costs incurred as a result of the releases from the Idarado site. Comment; One individual commented that the state consist ently failed to recognize natural environmental background condi- u -127- n tions at the Idarado site. L Response; The state has reported the localized natural background conditions in its RI/FS reports and at the public meetings for all elements of the environment except ground water G LJ and fish. n Comment: One individual commented that the state did not take into consideration in its FS -the stability of the tailings P piles in their present condition, or the no action alternatives. Response; The state has considered the chemical and physi- P cal stability of the tailings piles and the no action alterna- P fives in its selection of a remedy, and has selected the most P cost-effective solutions that will most permanently remediate the f sources at the site. Comment; One individual commented that the state did not U properly address the applicable standards to be applied at the p site. Response: A discussion of all legally applicable or rele- I vant and appropriate standards, requirements, criteria or limita- tions is set forth in Section 5 of this ROD. p LJ Comment: One individual submitted extensive comments on P the RI/FS and stressed that the primary factor in selecting the proper remedial action must be protection of health, welfare and / the environment. They recommended complete removal of the tail- ings, waste rock and stream sediments and disposal of this mate- G -128- Q p rial in a RCRA site. As a second choice, it was recommended that if the state selected backfilling the mine with the tailings, J that the slimes and low pH waste materials be removed and dis- posed of in a RCRA facility, in addition to diversion of high GJ country waters. Finally, they recommended a security trust p account be established in the event of failure of the selected L plan to achieve its intended goals. The discussion of capping the tailings piles stated that a capillary barrier must be placed LJ over the cap or seal, as is currently done with uranium mill u tailings. This individual was doubtful about the ability to cap the materials at the Idarado site, but noted that if a cap were used the design events with a return period of 10,000 years or more must be used to assure confidence in design stability for a period of 200 years, A 10,000 year design would reduce the probability of failure to approximate 2 percent in 200 years. Further, this type of design would reduce maintenance costs at the site. Another individual submitted written comments stating that anything less than a long-term, environmentally stable solution 0 is no solution at all. They recommended a pilot program to test backfilling the mine with the tailings, and the installation of a water treatment plant or plants to remediate the drainage prob lems from the mine portals. Capping the tailings piles was opposed because: the methodology is largely untested, capping -129- 0 y will not protect seepage of contaminants from beneath the pile, and capping the piles does not address the mine flow from the y portals. They also opposed direct revegetation of the tailings P piles. J-^ Response: As discussed previously, the state is confident P that a multilayer cap which is designed properly is an adequate U permanent remedy for the tailings .piles to protect the health, L welfare and environment of the area. Tailings piles Nos. 1 P through 4 are being consolidated onto pile Nos. 5-6 in order to LJ remove those piles from the San Miguel River. The cap is n designed with a lower permeability layer to stop seepage through the pile, and drainage layer to promote runoff above the tailings L rather than after the water has contact with tailings. Finally, P the cap is designed to withstand a probable maximum flood, which LJ design criteria will insure the stability of the cap and the P tailings piles. Comment; Some individuals commented that the state had not L followed the requirements of the National Contingency Plan in its PP-^ action to clean up the Idarado site. Response; The state brought this action against Idarado based upon its awareness of the degradation of the environment caused by the Idarado site. The studies conducted by the state were conducted to determine the extent of contamination and the potential methods to mitigate and minimize the environmental deg- -130- P radation. Moreover, pursuant to EPA guidelines, it is proper to determine that more tests are necessary in a Remedial Investiga tion report. The submission of the state's RI to the ATSDR, the TSCA inspection conducted by the EPA and the concerns addressed P by the state regarding the site have directly followed the guide- p lines of the National Contingency Plan, the EPA guidelines and CERCLA, as amended by SARA. ] i The state's screening of the alternatives in its Feasi- bility Study followed the EPA guidelines and the National Contin- Z gency Plan. The screening is discussed fully in section 2 of the p state's Feasibility Study and section 2.0 of this Record of Deci sion. In addition, the state does not believe that any federally I permitted releases occur at the site. Comment; Comments that the state failed to allow public P participation. Response; The state has conducted an extensive effort not P only to keep the public informed, but also to respond to the local residents' concerns and requests to simplify the informa u tion generated so that the public could participate in this pro cess. The specific points addressed in Idarado's comments sub mitted to the state have been taken into consideration in the 'L_J state's selection of a remedy. I Comment: Several individuals commented that the state's RI/FS report failed to consider several items such as the water P -131- n currently added to the tailings piles, the impermeability of the slimes portion of the tailings, failure to consider the different screening sizes used by the state and Idarado in their sediment samples, failure to consider some of the sample results of the state in the discussions, and kinetic problems associated with precipitation of lead and zinc. In addition, the report did not Q explain why zinc did not fit the defendants' model and assump tions used in this model. Response: The state's RI/FS report did consider the amount of water being added to the tailings piles as found in Table 3,2-1 of the RI. The permeability values for the tailings piles were used for both the sands and slimes portions in calculating u the tailings pile seepage. The state recognizes that Idarado and the state used different screening sizes for sediment samples. With regard to sample results, the state has attempted to utilize all available results in analyzing the problems at and solutions for the Idarado site. The kinetic problems associated with pre 0 cipitation of lead and zinc do not change the releases from the tailings piles nor the proposed remediation action. Comment; One individual disputed the state's use of cri teria for harmful levels of metals in plants and soils. Response: The levels used by the state are levels neces sary to protect health and the environment. These levels were confirmed by the ATSDR, The background level for soils in 0 -132- Telluride appears to be well below the levels found. Comment: One individual stated that the metals levels in the fish do not pose a health risk. p Response: The conclusion of the ATSDR that the metal L levels do pose a potential health risk, p-) Comment: One individual concluded that the fish are not GJ being stressed by metals in the San Miguel River, 1 Response: It is the state's finding that the male/female ratio of fish, the lack of variety of species of fish, the P reduced population of fish and the reduced number of macroinver- p tebrates in the river show that the fish in the San Miguel River are stressed. 0 Comment: One individual commented that poor water quality due to the mining activity is the cause of the lack of aquatic life in the Red Mountain District, Response; The state agrees with this statement. p Comment; One individual stated that drinking water stan dards should be applied to the San Miguel River for the purposes of remediation, J Response; The state has determined that EPA coldwater p aquatic life criteria are the relevant and appropriate require ments to apply to assure protection of aquatic life for the San p Miguel River and the Uncompahgre River. Ground water's contribu tion to the violations of stream standards due to its G -133- hydrological connection to the stream, must also be taken into consideration. Comment: Several individuals commented that they did not support the lawsuit or their tax money being spent on the law suit, that the lawsuit is unfair, and that CERCLA should not be applied to mining sites. These individuals also questioned whether the suit will harm the mining industry, agriculture and p economics in western Colorado. Response: The state brought this lawsuit pursuant to CERCLA GJ in order to protect the health, welfare and environment of the P State of Colorado. The Idarado Mine has historically had envi ronmental problems in the area, for example tailings blowing into / the Town of Telluride and excessive amounts of hexavalent chromi um released into Telluride's ground water. In addition, numerous U discharges are occurring at the site in both the Telluride and P Red Mountain Districts, and discarded barrels containing hazard- IP OUS substances and discarded transformers containing PCB's were J I discovered at the site. Thus, at the time the suit was brought there had been documented releases of hazardous substances into GJ P the environment. n Since the filing of the lawsuit, the state conducted a Ll Remedial Investigation and Feasibility Study (RI/FS) pursuant to the National Contingency Plan, 40 C.F.R., part 300. The studies of the site included the following: G -134- p 1. The review of all data and information provided by the defendants, Idarado Mining Co., Newmont Mining Corporation I and Newmont Services, Ltd., as well as all of the studies and data gathered by consultants for this lawsuit. L 2. The review of all files of the Colorado Department of Health, the Division of Wildlife, the Mined Land Reclamation G Division and other state departments and agencies. G 3. The review of all information provided by the United States Environmental Agency, U.S. Geological Survey, local gov- P ernments and libraries. p 4. Field investigations and sampling of surface water, sediments and biota in or near site drainages, including the San / Miguel River and Red Mountain Creek and the Uncompahgre River; sampling of existing ground water wells and drilling and sampling P of new wells; sampling soils and vegetation at various on and p off-site locations; sampling of tailings and sampling of on-site u barrels and transformers. 5. Screening the effectiveness of various alternative n remedies pursuant to the National Contingency Plan. The state sent its Remedial Investigation report which incorporated the above information to the Regional Public Health Advisor of the Agency for Toxic Substances and Disease Registry (ATSDR) to conduct a health risk assessment for the site. The ATSDR provided the assessment to the state and the defendants on -135- 0 p August 14, 1986, and made its recommendations which included GJ taking soil samples in residential areas in Telluride. The state I and the defendants sampled the soils in the residential areas in Telluride and approximately one-third of the soils contained lead P z in levels which ATSDR considers to be of concern to protect human u health. The results of the fish studies are in the process of being studied. The historical data, the past environmental degradation, the state and defendant's studies, and the ATSDR health risk assessment confirm the lawsuit is necessary to protect the health, welfare and environment of the area. Comment: One individual commented that this lawsuit would never have been brought if Idarado was currently operating and paying taxes. Response: The CERCLA lawsuit was initiated by the state as trustee for the natural resources to protect the public health, welfare and the environment to address releases of hazardous sub stances. The suit would have been brought whether or not Idarado was currently operating. Comment; Other individuals commented that mining companies should be held responsible for the environmental problems created P P by them and that the "down-side" of mining requires responsibil ity for these problems. Others felt that the more the mining companies damaged the environment and profited by their oper- -136- u ations, the more they should bear the responsibility for cleaning p up the site. Response: The purpose of CERCLA is to require the parties responsible for releasing hazardous substances to bear the costs n and responsibility for remedying the harmful conditions they cre ated. The responsibility is determined by the amount of harm caused to the environment - not by the amount of profits gleaned G by an operation. Comment: Several individuals commented that the state should drop the lawsuit and pursue the cleanup of Idarado's oper ations under the Mined Land Reclamation (MLR) Act. Response: The vast majority of Idarado's operations do not fall under the jurisdiction of the MLR Act. Specifically, tail ings piles Nos. 1-4 on the Telluride side and tailings piles Nos. P U 1-4 on the Red Mountain side are not covered under the existing p MLR permit. Further, the Mined Land Reclamation Division does not have jurisdiction over mine water or tailings pile discharges to surface waters. These discharges are addressed in the Reme dial Action Plan as are remedial actions for all of the tailings J piles on site. Therefore, the Mined Land Reclamation Board would r\ not have the statutory authority to require the proper response from Idarado pursuant to that Act. ) \ Comment: Several individuals expressed gratitude to the state for bringing the lawsuit and bringing the environmental Q -137- p problems into focus while others stated that the suit should not have been brought until it was determined whether or not a health P1 / risk existed at the site. Others encouraged the state to clean up the site now while Idarado is still a viable operation in Col- y orado. Others encouraged the state to choose a long term solu- p tion because the opportunity to clean up the site may not arise again. Several stated that environmental protection and aesthet ics should be a primary concern of the selected remedy. Response: The state acknowledges these comments. Public P J health and welfare and environmental protection are the primary p concerns to the state. Comment: At the first public meetings held on July 28 and 29, several individuals commented that the public did not have enough information to make comments because the RI/FS reports p were too technical and complex to understand. They requested the u state to prepare a summary of the information in the reports, and to extend the public comment period until after the public could review the summaries and after the soils in residential areas in Telluride were sampled as recommended by ATSDR. Response; The state responded by preparing and distributing two summaries for the citizens of Ouray and Telluride. The state also extended the public comment period and returned for another round of public meetings after the summaries were distributed and the residential soils in Telluride were tested. -138- D G p n Comment; Several individuals requested that the state u settle the lawsuit with the defendants and that the parties L attempt to reach a compromise that would benefit the mining industry and the environment. P py Response: The parties are and have been engaged in settle P ment negotiations, and the state encourages settlement discus sions in this matter. Comments: At the public meeting on July 29, 1986, two P individuals commented that the state should stop issuing harmful P press releases. P Response: As these individuals were informed at the meet ing, the state had issued no press releases. P Comment: Representatives of Idarado had their own public meetings prior to the state's meetings on July 28 and 29, 1986, p where they submitted a proposal to the public. The state was n later informed that Idarado's proposal was a settlement offer ( I J which had been extended to the state. The comments received by p the state regarding Idarado's proposal were divided. Some indi viduals expressed the option that Idarado's plan is unreasonable, p while other individuals expressed support for Idarado's plan. p Response: Idarado's plan is similar to alternative 5 of the PS in both the Red Mountain and Telluride Districts and is dis- PI cussed in the FS. Alternative 5 has additional remedial options to handle environmental problems at the site not addressed in V p Idarado's plan. J Comment: Several individuals stated that the lawsuit may I / have an adverse impact on tourism, on the agricultural industry, on mining, and on business in Colorado. Others stated that the P y cleanup is the most important issue and that the area should p experience economic benefits from the cleanup. Response: It is important to note that as stated previously C] the state as public trustee is charged under CERCLA to protect the health, welfare and environment of its citizens. Any adverse impacts caused by the publicity of this action are the result of the environmental degradation in the first instance, not the attempt to remedy the situation. Comment: Several individuals at the Ouray public meetings expressed concern regarding property value loss of other mine owners and properties adjacent to the Idarado site. They asked who would compensate these property owners if they did suffer an economic loss. Response: The state's role as public trustee for all natu ral resources permits it to recover damages under CERCLA, for injuries to the public interests in the natural resources. The state does not presently seek to recover damages from Idarado for G injuries to private interests. n P Comment: One individual commented that the money the state has expended on the Remedial Investigation and Feasibility Study -140- G n to date should have been spent towards cleanup of the site. Response; As stated previously, the state and Idarado are presently engaged in settlement negotiations. The money which has been spent to date has been necessary to determine the nature and extent of contamination and thereby provide a cost effective cleanup at the site. G Comment: Several individuals requested that the state, in selecting the remedy for the site, consider: 1) aesthetics; 2) protection of historical mining sites; 3) protection of the alpine tundra; and 4) costs. Others commented that the state should be objective in its selection of a remedy. It was also stated that the state should involve local citizens in making the final decision on the remedy. Response: Pursuant to the National Contingency Plan, the appropriate extent of remedy is a cost effective remedial alter native that effectively mitigates and minimizes threats to and provides adequate protection of public health and welfare and the environment. The considerations include cost, technology, relia bility, institutional and other concerns, and their relevant effects on public health and welfare and the environment. The state also considered any significant adverse environmental and G health impacts and the technical practicality of the remedy. The state has considered the site specific concerns of protection of the alpine tundra and the historical mining sites, and aesthetics G -141- D of the area, as these local concerns were expressed by numerous p citizens. Comment: Some citizens in Ouray requested that the state select a remedy that does not prevent future mining in the area. p Response: The state has attempted to select a remedy that p does not preclude future mining at the site. In particular, backfilling the mines is not the preferred remedy. Comment: One individual asked who performed the state's studies and wrote the reports. Response: The consultants hired by the state to conduct the Remedial Investigation and Feasibility Studies and to write the 0 reports are GeoTrans, Inc. of Boulder, Rocky Mountain Consult- P ants. Inc. of Boulder, and ERI Logan, Inc. of Logan, Utah. Comment: One commentor asked why there were different n J results with split samples analyzed by the state and Idarado. p Response: Most of the samples split between the parties JJ are not significantly different; rather the interpretation of the P results differ. The state has employed a stringent quality assurance quality control procedure to assure that its results P are accurate. The quality assurance quality control procedures p are fully addressed in Appendix B to the state's Remedial Inves tigation report. I I Comment: One individual comments that the state has misin- P terpreted its data. G -142- n, P Response: The state is fully confident that the interpre tations by its experts of the data gathered in the RI/FS investi- P gation are correct. Comment: One individual asked where the state's control P y samples for air, fish and soils were. p Response: The state's soils samples indicate that the background lead levels in soils are approximately 60 parts per P million. There are no "control" samples for fish and air. P all ofComment the proposal: One scommento on Sanr Juaasken dCounty what. woul d be the effects of Response; The only foreseeable adverse effect on San Juan County of alternatives one through five are possible traffic con gestion on Highway 550 between Ouray and San Juan Counties if UJ truck hauling is utilized. The only adverse effect on San Juan County citizens, as well as all state citizens, of alternative six is failure to effectively mitigate and minimize the environ mental degradation caused by the releases at the site. Benefits to San Juan County may be derived from increased employment opportunities during site remediation and increased tourism LJ resulting from a cleaner environment. P Comment; Several individuals expressed opposition to P alternative No. 1 in both the Red Mountain and Telluride Dis trict because of the truck traffic required for off-site disposal and because of the dust problems that would be created by moving -143- c p the tailings piles. Response: The adverse impacts of off-site disposal have been considered by the state, as well as the permanence of the p alternative. The Remedial Action Plan selected in this document has rejected off-site disposal of tailings and waste rock piles in favor of more environmentally acceptable and cost effective actions. Comment: One individual commented that the state did not LJ P consider maintenance costs of the alternatives. Lj Response: The maintenance costs were calculated and con- p sidered, and are found in the Feasibility Study report. Comment: One individual asked whether the state has con- f ducted an economic assessment of the impact of the remedies. Response: The state has not conducted an economic assess- _J ment of the impact of the remedies. p Comment: One individual commented that all six alterna- ^ fives in the state's Feasibility Study were unrealistic and n impractical. I Response: The six alternatives in each district were J screened for technical feasibility during the Feasibility Study p phase of this investigation. The state is confident that the alternatives in its Feasibility Study are realistic and techni cally feasible based on the judgment of the state and the state's consultants. P G -144- n I LG P Comment: One individual opposed the option in the Feasi- bility Study of mine portal sealing because of uncertainties I involving the water and because of the chances of a blowout. Response: These uncertainties have been considered in the p selection of the remedy for this site. Where sealing or portal P plugging is being contemplated, detailed investigations will be P performed prior to construction in order to assure that proper P design is undertaken and that the action will not cause addi n tional adverse effects. LJ Comment: Several commentors were concerned about the n health effects of the metals released into the environment. One LJ individual asked whether releases from the tailings piles could P P cause craniosyntosis. Response: At this time there is no indication that the tailings piles have caused craniosyntosis. As one individual commented, however, the health risks of long term exposure to low levels of heavy metals is not now well known. Comment: One individual questioned why all of the alterna P tives were so expensive. Response: The Idarado facility is a large site covering p roughly 13 square miles and spanning two major drainages. There u are three major sources of contamination at the site—tailings, mine drainage and mine waste rock. In addition, there were PCB's and other organics discovered on site. The figures in the •vJ -145- P state's Feasibility Study assumed what the consultants believed _j to be extremely conservative estimates of the amount of materials P J to be cleaned up and of the costs of implementing the remedies. n In developing the Record of Decision, the state has attempted to LJ revise and reduce the costs of the cleanup efforts wherever pos sible. Comment: Several individuals commented that the ultimate n p goal in the selection of a remedy should be clean water. Others stated that the state should only consider permanent solutions to G the problem. ~] Response: As stated previously, the cost effectiveness as well as the permanence of the remedy in reducing releases to _] soils, water and air has been considered by the state pursuant to p the National Contingency Plan. Comment: Numerous individuals stated that an Alpine Recla- P mation Center should be funded and organized in Telluride to study the impacts of and solutions to environmental degradation p L caused by mining companies. p Response: Although the concept of an Alpine Reclamation Center is innovative and an excellent proposition, the creation P of such an institution is not within the purview of the state's trusteeship pursuant to CERCLA. The state would welcome the cre ation of such an institution by private individuals. P -146- P 6.1.2. Telluride District L Comment: Many individuals in Telluride commented on spe- p. cific alternatives for the Telluride District in the Feasibility LJ Study. A general summary of these comments follows: P Alternative 1 (off-site disposal) - Numerous individuals in the Town of Telluride supported off-site disposal of the tailings P J pile material. Many of these individuals supported off-site dis- P posal if if were feasible and did not cause extremely adverse L short term adverse effects. Several of the comments expressed a P concern to keep the historic Tomboy Mine ruins intact as a modification to off-site disposal. P p Alternative 2 (Backfilling the mine with tailings) - Numer- P OUS individuals supported the alternative of backfilling the mine ^ with a portion of the tailings and reclaiming the remaining tail ings. Another commentor questioned whether backfilling the mine was technically feasible from an engineering standpoint. _ Alternative 6 (no action) - was opposed by several indi- P viduals in Telluride. n P Response; The state has evaluated the above alternatives pursuant to the National Contingency Plan, as discussed in this ROD. It should be noted that CERCLA was recently amended by the y Superfund Amendments and Reauthorization Act of 1986, Pub. L. P 99-962. The amendments contain a guidance for cleanup standards -147- to be considered when selecting a remedial action. In section 121 of the amendments, it is provided that actions in which treatment which permanently and significantly reduce the volume, toxicity or mobility of hazardous substances, pollutants and con taminants is a principal element are to be preferred over reme dial actions not involving such treatment. The section further provides that off-site transport and disposal of these materials without such treatment should be the least favored alternative remedial action where practicable treatment technologies are available, pI j The state was required to consider the short term and long term potential for adverse health effects from off-site disposal of the tailings relating to blowing dust, traffic accidents and the long term problems associated with the future disposal of the tailings. In addition, the state had to consider the effects of off-site disposal on the environment. Based upon the feasi bility, practicality and technical reliability of capping the tailings piles, the off-site disposal alternative was not se lected by the state. Backfilling of mines is a proven technology that is cur rently being used in Canada and other countries. However, uncer tainties do exist with backfilling including the path of any water in the mine, the quality of the water, the ultimate point of release and the lack of control of future releases. The many -148- f) miles of interconnected workings and numerous portals make the u prediction of outflow points and the water quality of the J outflows extremely difficult. Other problems are the accessibil- pi ity to some areas of the mine and the possible detrimental effects on future operations. All of the tailings cannot be placed back into the mine. Thus, remedial actions for some tail ings will still have to be undertaken at the surface. For these P reasons, consolidation and capping of the tailings was considered p to be more cost effective than backfilling. Comment; Several individuals in Telluride expressed a con Q cern that the environment should be taken into consideration as Q well as health matters. Response; The state has chosen a remedial action which takes into consideration the environment as well as health related matters. Comment: One individual asked whether the city wells were potable at this time. Response: The city wells are cleaner than primary drinking water standards, but still exceed the secondary standards for manganese and iron. As long as Idarado is in temporary cessation there is a potential that the mine will reopen. The Health Department has taken the position that the proximity of the wells to the tailings piles and the potential for the mine reopening render the wells unpotable. When the Health Department is -149- assured that: 1) the tailings piles are remediated, 2) the mine will not reopen, and 3) there is adequate and regular monitoring G of the wells, the wells will be authorized for use as a drinking water supply as long as they meet all relevant drinking water standards. Comment; Based upon the lead contained in the soils in Telluride and the potential health risk associated with the lead n levels, many individuals expressed an extreme concern that the p soils in the Town of Telluride be remediated. One individual requested that the soils in the Town be cleaned up until they did not exceed 100 parts per million (PPM) lead. Based on the recom mendations of the ATSDR, soils with lead concentrations exceeding P J 500 ppm will be remediated in the Town of Telluride, p Comment; One individual commented that the direct revegetation of the tailings piles proposed by the defendants has P not been successful to date even though the defendants have been experimenting with revegetation since approximately 1969. L Response: The uncertainties of the success of direct G revegetation is one of the concerns considered by the state in its evaluation, along with the potential uptake of metals in the n vegetation, and the inability of direct revegetation to minimize ground water seepage and surface water and wind erosion. L Comment: One individual asked why the alternatives had not p been tested over the past year before a final decision on an P _ -150- p alternative was made. Response: Two major reasons that the alternatives could P not be implemented on an experimental basis are: 1) the site had p to be studied in order to determine the nature and extent of harm and in order to determine the appropriate remedy; and 2) experimenting with the different alternatives would become extremely costly to the defendants and/or the state. Ll Comment: One individual asked the state how it would dif- p ferentiate between Idarado's and other's contributions of lead in the soils in the Town of Telluride, Response: The state is not required to differentiate between the contributions of Idarado and others, as CERCLA pro- P vides for joint and several liability and provides for the right p of contribution for Idarado from other potentially liable par ties, Idarado has the right to join other parties into the law- — suit which it believes contributed to the elevated levels of lead in the soils in Telluride. J Comment: Several individuals asked the state to consider p general objectives in selecting the remedy for the site. These objectives included: 1) isolate the tailings and keep them from getting into the river; 2) clean up the river bed and banks in order to improve aquatic life; 3) monitor the area for hazardous P substances; and 4) eliminate the source of contaminants as well p as off-site migration. -151- Response: All of these objectives have been taken into consideration by the state in selecting the remedy for the site. P Isolation of the tailings piles has been a major concern p addressed in the remedial action plan. The multi-layer cap on the tailings piles will eliminate surface water and wind erosion and will minimize any seepage into the ground water through the I P tailings. The remedial action plan includes an extensive moni- LJ toring program to assure the state and local citizens of a clean p environment. The plan also includes removal of the tailings adjacent to the San Miguel River in order to provide a suitable environment for aquatic life and reduce threats of future human exposure. P Comment: One individual asked the state to identify the p source of topsoil that could be used as the vegetative layer on the tailings piles. n [ Response: When the FS was written, the source of topsoil costed was from outside the Town of Telluride. Numerous resi- P dents in the Town of Telluride expressed opposition to the traf- p fie problems that would be associated with importing topsoil to the site. In response to these concerns, the state conducted a survey of Idarado's property to attempt to locate on-site mate P rials that could be used together with other material as a top- LJ soil for a cap on the tailings piles. Suitable materials may be p found on Idarado's property; thus, topsoil would not have to be r^ -152- imported into the Town of Telluride. However, a small amount of mulching material may have to be trucked through town. 6.1.3. Red Mountain District Comment: Several individuals in the Red Mountain District commented that Idarado should not be required to pay for the n cleanup of Ridgway Reservoir. p Response: This lawsuit was brought for damages and costs of cleanup of the releases of hazardous substances at the Idarado I site. The cleanup of the environmental degradation caused by the releases would be required whether or not the Ridgway Reservoir P was currently being constructed. p Comment: Numerous individuals in the Red Mountain District submitted copies of a form letter stating that the alternatives P in the Feasibility Study are unrealistic, that the cleanup should be conducted under Idarado's mined land reclamation permit, and P . . U that the lawsuit has negative effects on the mining industry, p agriculture, and tourism in the area. p Response; These comments have been previously addressed in P- the general (entire site) section. However, it should be again noted that the only area in the Red Mountain District over which the Mined Land Reclamation Division has jurisdiction is the Red Mountain Mill Yard area. -153- Comment: One individual noted that there will be problems in using the Ridgway Reservoir for recreation without a cleanup. L Response; The state agrees. The state's study shows that p there will be problems created by metals contamination in Ridgway Reservoir if no adequate remedial action is taken. Comment; One individual asked how the state will address the mining companies other than Idarado that are contributing to P the contamination in Red Mountain Creek and the Uncompahgre p River. Response; Under CERCLA the state is not required to bring a lawsuit against every potentially responsible party. In this case, the state brought the lawsuit against the defendants as the P major contributor of contamination in the Telluride and Red Moun- P tain Districts. Idarado, however, has a right pursuant to CERCLA to bring an action against the other responsible parties for their contribution. Idarado has asserted this right in this case and has sued other potential contributors for their share of the n . • LJ contamination. n Comment; One individual commented that because of the lack of knowledge of the effects of long term exposure to heavy metals, that there are potential future health hazards in the Red ^ Mountain district. p P Response; It is true that there is not a large amount of P knowledge on the health effects of long term exposure to low r^ -154- rn levels of metals. However, based upon the current state of knowledge and current data, the ATSDR has determined that there are no known health risks in the Red Mountain district at this time. Comment; Several individuals submitted a comment support ing the remedial plan submitted by Idarado, and requesting that the parties attempt to settle this lawsuit. The comment focused p y on potential health risks. p Response: In addition to potential health risks, the envi ronment must also be protected by the remedial plan adopted for j the site. The Remedial Action Plan proposed in this document more effectively protects public health and the environment than P Idarado's proposal. p Several individuals opposed alternative one (off-site dis posal) and alternative two (disposal in on-site lined impound ment) because of the traffic problems that would be created on Highway 550. They also opposed treatment of the mine discharge P because of the expense of such treatment. p Response: A treatment system is necessary in order to effectively cleanup the surface water in the Uncompahgre River 1 and Red Mountain Creek. Comment: Several individuals opposed consolidation of the P tailings and mine waste into pile No. 4. p Response; The consolidation of tailings is necessary to P _ -155- Q isolate these wastes and reduce their releases to the hydrologic system. Tailings pile No. 4 is in the most stable geologic loca- P tion of all the piles on the Red Mountain side. Surface erosion P and ground water seepage problems would be greatly reduced by U consolidating all tailings to this site. In addition, after con solidation of the mining wastes, only one cap and monitoring sys- tem is required in the Red Mountain district, as opposed to five P caps and five monitoring systems, which is economically benefi- y cial to Idarado. Comment: These individuals also opposed diversion of the mine portal discharge water from the Telluride District to the Red Mountain District. P Response; The diversion of all mine portal water above the p 1200 level of the mine by gravity to the Treasury Tunnel is an economical and practical way to divert the water for use in a P passive treatment system for Red Mountain Creek. Comment; Several individuals opposed removal of stream P sediments downstream of Ironton Park because of its p impracticality. Response: The removal of the sediments is necessary in 1 order to minimize contamination in the Uncompahgre River because the sediments are significant secondary sources of contamination P as a result of the precipitation of metals from the surface p water. n -156- Comment: Some individuals oppose the removal of organic wastes from the site. Response: The removal of organic hazardous wastes is required by other federal and state laws. The only proper dis p posal of these wastes is in a RCRA permitted facility. Comment: One commentator recommended construction of a water treatment plant similar to the one built by AMAX on Coal Creek near Crested Butte. Several others agreed with this view. Response: The state's consultants considered such a water treatment plant in the Red Mountain District but screened it out due to the size of the treatment plant that would be required due to the high amount of flow in Red Mountain Creek (300 cfs during spring runoff). The diversion of water above the 1200 level in the mine, the limestone treatment, and the reservoir are more economical but comparatively effective actions. They also require less maintenance than an active water treatment plant. Comment: One person commented that the state's reports clearly showed that there was contamination in Red Mountain Creek and the Uncompahgre River due to mining and that it was not natu ral contamination, as believed by some individuals. Response; The state agrees. The samples gathered by the consultants show that although there are naturally occurring metals in the surface water, the cause of the elevated levels of metals is mining by Idarado and others. -157- Comment; Several individuals thanked the state for working to cleanup the water in the Red Mountain District. One of these individuals suggested that the first public meeting in Ouray was attended by and represented the mining industry as opposed to residents of Ouray County. Another individual stated that she would support Idarado's proposal jj^ Idarado did what it said it would do and if its plan would successfully mitigate the harm in p the Uncompahgre River. Response; The state acknowledges these comments. As previously discussed, the state has determined that Idarado's proposal will not effectively mitigate the contamination in either Red Mountain Creek or the Uncompahgre River. Comment: One individual suggested that cleaning up the metals in the Uncompahgre River would harm downstream agricul tural land by neutralizing the acidic water in the irrigation ditches. Response; The elimination of the metals from the water used to irrigate downstream crops will effectively improve, not hinder, downstream crops since the metal loads in irrigation waters would be decreased. 6.2 THE RECORD OF DECISION PROCESS On February 9, 1987, the state issued its Preliminary p p -158- Ul Record of Decision for the Idarado Mining and Milling Complex, presenting the state's proposed Remedial Action Plan for the Idarado Mine facility. The Preliminary Record of Decision was based upon the nature and extent of contamination defined in the state's Remedial Investigation Report, the range of remedial alternatives, presented in the Feasibility Study and public com ments. The Preliminary Record of Decision was made available to UJ the public in the same manner as the RI/FS reports. A 30-day public comment period was held from February 10, 1987 to March 11, 1987. Public comments were received by the Colorado Depart p ment of Health, a public meeting was held in Telluride on March Q 2, 1987, and a telephone conference was held on March 9, 1987 with Ouray officials and interested Ouray citizens. The comments regarding the Preliminary Record of Decision P formally submitted either at the public meeting, conference, P phone call, or in writing were considered in the selection of the I final remedial action and are responded to herein. In an effort to avoid redundancy, similar comments will be addressed with a P single response. Moreover, if the comments were previously p responded to in the preceding RI/FS section responses, the reader is referred to section 6.1. Comment: Comments were made that the PROD was totally silent on the necessary measures to mitigate the socioeconomic -159- p Q Q p impacts during the remediation and permanently as a result of the remediation. Further, the Town of Telluride must be afforded a n lead role in outlining the necessary measures to preclude adverse impacts. Specifically four areas of concern existed: L 1« the potential for temporary or permanent dislocation p of citizens in the Pandora and Liberty Bell areas; 2. the planning and mitigation work necessary for a sig- p nificant change of work force in the community, n 3. impact on tourism during remediation activities, and P 4. development of a complete socioeconomic plan. p Response: The final ROD has been changed to include provi sions for inclusion of local government officials in redevelop- / j ment of mitigation measures to minimize the social-economic im pacts of implementation of the RAP. Specifically, the RAP calls U for local involvement regarding the a relocation study to deter- p mine if citizens may be relocated and provides for a cost esti mate for those activities. Results of this study will be dis- I cussed with the Town of Telluride. The impact of the remedial n activities on tourism will be small with the possible exception P of the soils clean-up in the Town of Telluride. The ROD incorpo- p rates this condern by stating that soils cleanup in the Town of Telluride shall be conducted in cooperation with the Town. ] The state has developed a draft projection of the number of L jobs to be created by the remediation action to be undertaken. •160- Q p For the remedy described in the PROD, over 400 man-years of labor are estimated to be needed. p Comment; Several individuals had concerns about the reme dial actions to be performed in the High Country, Specifically P these individuals emphasized the need for maximizing protection p of the fragile alpine ecosystem and minimizing the disruption to the appearance of the high basins. Widening of current roads was opposed and construction of new roads should be minimized accord ing to these individuals. Further the existing mine structures n P should be stabilized and maintained, p Response: The ROD reflects these concerns. The selection of the remedial actions for the High Country (chapter 5) is based ^ on minimizing environmental disturbance and road construction or improvements. Section 3,4,1,2 specifically states that "All mea- P sures will be taken to avoid destruction of historic mining Q structures," The construction of diversion ditches should not disrupt the appearance of the basin. Comment; Several individuals supported the concepts out- P lined in the PROD to remediate contaminated soils in the Town of p Telluride but felt that the cleanup levels should be reviewed and reduced accordingly. It was recommended that a borehole sampling ; program with a grid spacing similar to the existing study should be instituted along with sample collection from various depths Q -161- p p P rather than a grid based program with repetitive analysis, in P order to expedite the cleanup. Disturbed areas should not be allowed to remain open while analysis is being undertaken. Fur ther, the Town of Telluride should be allowed to participate in P P the soils cleanup and these activities should be coordinated with p ongoing maintenance and construction activities in the town. Response; A comprehensive soil monitoring program is called for in the Final ROD, The purpose of this program is not only to assure that metals are removed at depth but also to be P certain that all residential areas with high lead levels are p identified. It is anticipated that a field test method for determining lead levels will be identified and utilized in the soils cleanup. This would allow rapid decision making concerning soils to be removed or covered. The final ROD calls for develop- G • . LPJ ment of an implementation program for soils cleanup in coopera tion with the Town of Telluride, Comment; Several individuals stated that the state's pro posed remedial action for tailings piles in the Telluride Valley was not acceptable until the following actions were undertaken; P 1, additional study of the socio-economic impacts and U costs of capping materials, excavation, transportation, construc tion and maintenance requirements of the cap for a cost-benefit analysis, and 2. the amount of reduction of water pollution from the -162- n 0 capping option should be estimated and compared to the overall water pollution problem from surface and ground waters throughout the watershed. Response; The state has reevaluated the remedial actions for tailings piles in the Telluride Valley, The Final ROD calls for consolidation of the Society Turn tailings material into a disposal site in the Society Turn area, A 6-foot cap would be placed on that material as well as on the consolidated tailings at piles No. 5 and No. 6. Tailings from Society Turn would not be transported through the Town of Telluride. Miscellaneous tailings along the San Miguel River would be transported to tail ings piles No. 5 and No. 6. The state has also evaluated trans portation methods for consolidation of tailings piles 1-4 onto No. 5 and No. 6. Conveyor, scraper and truck hauling have been evaluated. $21,265,890 was costed for the ROD (for both Red Mountain and Telluride). Maintenance requirements have also been evaluated and costed in the ROD. A cost-benefit analysis is not required under the NCP or SARA. However, a cost-effectiveness analysis is required and has been performed. Q The state has also evaluated the reduction in water pollu tion associated with capping of the tailings, and has determined that capping along with the other remedial activities will effec tively reduce contamination in the affected waters. Comment; Several individuals supported the need for addi- Q -163- u p tional studies prior to initiation of the remedial actions. Response: The state concurs that design investigations are necessary prior to implementation of the remedial actions. These investigations have been incorporated into the Final ROD. p Comment; Several individuals felt that the blood lead p study done by the University of Cincinnati on behalf of Idarado should be independently evaluated by a qualified epidemiologist. P P Commentors suggested that a stronger health evaluation is needed in the ROD. n GJ Response: The study has been evaluated by epidemiologists p from the state and the federal ATSDR. Based on its evaluation, the state has determined that more studies are necessary. More / details concerning public health studies have been placed in the final ROD. P Comment; One comment was concerned about the "baseline" p air quality: I am concerned about calling current air P quality a "baseline" to which changes I during remediation will be compared. It L seems that a more appropriate comparison now and during remediation, would be with P established ambient standards where avail- P able as guidance levels based on possible health effects. P Response; Air quality monitoring during construction of P the remedial actions will be required pursuant to the require- ^ ments of the Colorado Air Quality Control Act. Capping of the P tailings will eliminate the blowing tailings from the pile. -164- Comment: One comment suggested that we expand the chemical constituents to include arsenic for air quality analysis. Response: An Air Quality Control Division permit will be required for the site during construction of remedial activities. ( U Once the cap is in place, blowing of tailings will be eliminated. p Thus, on going monitoring for air quality will not be necessary. Comment; One comment suggested that cleanup, at the dif p p ferent sites should be similar especially for water quality cri- teria. U Response; The state has evaluated the applicable, rele- p vant, and appropriate standards for water quality in the Uncompahgre and San Miguel River Basins. The evaluation is set j forth in section 4.0 of the Final Record of Decision. Comment: One commentor was concerned about using limestone n : P as a neutralizing agent for mine drainage. p Response; The state has proposed charging Red Mountain Creek with limestone. Red Mountain Creek has a steep gradient which will allow the limestone to be transported downstream. The transport of the limestone will cause the coating to be removed P if the limestone is sized correctly. uP Comment: One comment suggested that neutralization and sedimentation water treatment techniques proposed in the Prelimi- i , nary Record of Decision conflict with other NPDES permits. Responses: Sedimentation is typically used to reduce sus- -165- p pended solids from mining discharges. Neutralization is also used to adjust the acidity of low pH mine waters. Both of these n techniques have been employed elsewhere in Colorado. In addi tion, as discussed in section 4.0 of the ROD, any point source L discharges are subject to effluent limitations as required by a p CDPS permit. Comment: One individual asked whether metals concentra- P tions in water were based on dissolved, total recoverable or total metals analysis. L Response: Ground water samples were analyzed for dissolved p metals. Surface water samples were analyzed for both dissolved and total metals. The procedures are outlined in the Quality Pl Control/Quality Assurance Plan found in the Appendices of the Remedial Investigation Report. P J Comment: Two comments were brought up, concerning stream p standards and compliance points: P 1, The surface water criteria for arsenic, cadmium, cop- P per and nickel are less restrictive than current water quality standards in the San Miguel River. Also, the point of compliance (J in the Uncompahgre River is unclear. p 2. Where is the point of compliance for stream standards to be in the San Miguel River? |P Response: The state has reevaluated the relevant and appropriate standards for surface water. The ROD has been Q -166- AM p changed and stream standards for the Uncompahgre River and the San Miguel River are identified as the applicable standards for p surface water quality, with the exception of zinc (.15 mg/l), lead (.004 mg/l) and copper (.005 mg/l), the standards appropri- P ate for adequate protection of aquatic life. The compliance p point for surface water quality on the Uncompahgre River is below the confluence with Canyon Creek. • For the San Miguel River, the P points of compliance are the San Miguel River below Bear Creek P and the San Miguel River just above the confluence with the South U Fork. Comment: One comment stressed that final closure studies should be delineated in the ROD. Response: The ROD has been changed and design investiga tions necessary for the development of final plans and specifica- P tions have been added. p Comment: One individual was concerned with the location of the borrow pit for the capping material for the tailing ponds. Apparently the proposed borrow pit is located right underneath the Pandora and Liberty Bell Trailer Courts. The individual P J claims that 10 percent of the work force for the Telluride Region p lives here and if they have to move there will be no place for them to go within the region; therefore, 10 percent of the work j ) force would not be available for work within the region. Response: The state is concerned about the dislocation of Q -167- p residents now living in the Pandora and Liberty Bell Trailer Parks. However these trailer parks are located very close to the tailings piles. Any remedial activities at the tailings piles would create traffic noise and dust problems. These conditions P P would not be conducive to residential living. The state has p attempted to address these concerns in two ways. The first is a design investigation to determine .if other suitable capping mate- / rial is available. The second study involves an investigation of areas for relocation of the residences on the Royer Gulch Fan. G] Li Comment: One individual submitted several historical arti- cles concerning the Uncompahgre River water quality prior to D mining within the region. He suggests that the water quality / problem was natural rather than man-caused. Response: Natural loading of metals to streams is a recog- P nized occurrence. However, mining activities have increased the p exposure of metal bearing rocks to water and air, thus increasing the metals loads to streams. The state's sampling programs have 1 indicated much lower metal levels in stream segments not impacted by mining activities in the region. P U Comment; One individual had specific comments on the Red Mountain Remedial Activities section 3.5 of the ROD. The com ments were made on each section as follows: 0 3.5.1.1: 0 a. The removal of the buried tailings pile and tailings -168- n p u piles 1-3 will result in making these areas susceptible to ero sion from surface storms, interfere and disrupt traffic on U.S. P Highway 550, and interfere with the tourist and jeep traffic in p the areas. b. With the doubtful availability of materials for these ! purposes, the high cost of transportation, and questionable P effectiveness of the multi-component cap, this would not be cost L=' effective. n c. Run-on drainage control should be practical and P effective for all tailings areas. Cribbing and other methods of stabilizing the base of tailings ponds 1-3 could be used. d. Borrow areas and tailings disturbance (removal) areas P should be kept to a minimum. p e. A vegetative cover should be seeded and cultivated on all tailings ponds. This, with run-on and run-off control, should effectively control wind and water erosion. P f. The impurities in the surface water from causes other than man's mining activities should not be charged against the mining operations in the area. 3.5.1.2: a. With stabilization of piles Nos. 1-3, by the use of cribbing and berms, the necessary cleanup of soils would be mini mized. b. By stabilizing perimeters of tailings ponds Nos. 1-3, -169- p 1 all tailings areas should be earthquake safe. c. Structures for flood and drainage control should be L adequately designed. p d. Run-on controls and vegetation should effectively P prevent infiltration. P e. Run-off control — satisfactory. f. Time should be allowed for vegetation to establish n p itself and best type of self-regenerative vegetation be deter- p mined. g. Vegetation should control air emissions. G and Ll i. These should allow for necessary changes during the p activities overall. Response: Tailings piles Nos, 1-3 on the Red Mountain side P are already susceptible to erosion. Evidence of significant ero sion exists on all three piles. The ROD proposes the use of a P J conveyor system to consolidate these piles, thus avoiding traffic p^ congestion along U.S. Highway 550, Removal of the tailings from P these areas will reduce the potential for future releases of metals. Materials available from the construction of a below grade reservoir can be used to cap the tailings. The analysis in the Feasibility Study indicates that consolidation and capping are cost effective solutions compared to inplace capping or -170- P P inplace direct revegetation. Run on drainage control will be utilized for all remaining tailings and waste rock piles. Crib- Pi y bing and other methods of stabilization are not as permanent as p the capping methods incorporated in the ROD. Borrow source areas P shall be kept to a minimum. Sufficient borrow material will be P available from the below grade reservoir. Additional materials LJ will not be required. The consolidated and capped tailings piles P will be revegetated in order to reduce infiltration and enhance p the aesthetics. Based on the analysis in the state's Feasibility Ui Study, revegetation and runon control are not nearly as effective as capping with runon control and revegetation. Earthquake stability, adequate flood protection and drainage control struc tures are called for in the ROD. The revegetation program P P described in section 4 does allow time for establishment of the best type of self-regenerating vegetation. Air emissions will be controlled by the capping of the tailings material. The effec tiveness of vegetation alone in reducing air emissions is less than the use of capping material and it has not been demonstrated that an adequate vegetative cover can be established directly on the tailings material. The state has held public meetings in both Ouray and Telluride to gain public input. The state has also met with local and county officials to discuss this project. Finally, the remedial actions outlined in the ROD have been found to be cost-effective solutions. -171- D Comment: One individual was concerned about the construc tion of a 2,000 acre-foot reservoir on his property and certain water rights issues. He outlined the potential for minable quan r tities of metals on the property and the potential for the area ^ to be developed into a resort area. The commentor also inquired P whether land acquisition costs have been considered by the state. Response: The ROD calls for a reservoir design study to p optimize the size, design and location of the reservoir. This p information will then be used to properly design and construct the reservoir. Thus, the final location and size have not been determined. Should the reservoir be located on this individual's property, purchase of that property would have to be undertaken. GJ This cost has been addressed in the ROD. Moreover, section p 3.7.4.8 of the ROD states that all remedial actions involving diversion or storage of water will have to meet the requirements n of the State Engineer. Comment: One individual was concerned about how the tail ings dust affects the residents of Telluride, as well as the fish and the land. Response: The tailings contain metals, including lead p which is a primary concern from a human health standpoint, and zinc which is a concern from an aquatic life standpoint. The levels of these two metals in tailings material have been found in the ranges shown below for tailings piles No. 5 and No. 6: -172- GP P P lead-1,070 ppm to 4,870 ppm zinc-1,290 ppm to 3,990 ppm. These levels of metals can be transported as tailings dust or can erode into surface water. When high levels of lead are found in soils, children who might ingest the soils are subject to ele vated blood lead levels. Blood lead levels of 80 ug/dl (micrograms per decilitre) in children can cause severe, irre versible brain damage. The ATSDR has recommended 25 ug/dl of blood lead as a safe level. When washed into the stream, tailings with high zinc and lead levels will yield some of these metals to the stream water. Zinc is extremely toxic to fish and will reduce the species of fish and the numbers of fish for a given species. Because of this, a standard of 0.15 mg/l of zinc has been established for U the San Miguel River. The effect of high metals levels on the land are reduction of vegetation and metals uptake in the vegetation. Comment: One individual was concerned about such drastic remedial action as an 8 foot cap. This individual's preference was for 1 foot of clean topsoil for dangerous levels at resi dences and more watering of vegetation to reduce dust.. Response; The state has reevaluated the remedial action for tailings in the Telluride Valley. Consolidation with capping, hydraulic improvements, revegetation and flood control -173- P p p P measures are the remedial options selected in the ROD. The thickness of the cap has been specifically reevaluated and 6 feet P is the cap thickness proposed in the ROD. Specific details will p be compiled in the final plans and specifications. It is envi- G^ sioned at this time that the 2 foot impermeable layer would be I I composed of tailings material from piles 1-4, mixed with benotonitic clay. On top of this layer would be placed 2 feet of P y erosion resistant random fill and 2 feet of plant growth media p from locally available sources. The cap is more effective at y reducing releases than direct revegetation and increased watering 1 of the tailings piles. With regard to soils with high lead levels around resi- Gl Z dences, the ROD calls for removal, covering, or treatment of Pp soils with lead levels in excess of 1000 ppm and cover, treatment on other controls for soils with lead levels between 500 ppm and 1000 ppm. Comment; One individual commented that it was not appro priate to improve fish habitat in Red Mountain Creek due to the steepness of the stream. Response: The state has reevaluated this issue and agrees. The ROD reflects this change. Comment: One individual commented that geological mapping and sampling of the mines should be conducted prior to adit plugging. -174- Q "1 J I j Response: The ROD only considers adit plugging in the High P Country Area. Adit plugging is not proposed in the Red Mountain J Creek drainage. Mapping and sampling in the High Country on p Idarado's property could be undertaken at Idarado's discretion. ^ Comment: One commentor raised concerns about the operation j and efficiency of the drainage layer in the tailings pile cap design. (1 P Response: The state has determined that the proposed p drainage layer in the tailings pile cap would be largely ineffec tive due to the flatslope of the layer. Moreover, cap infiltra- tion will be effectively minimized by evapotranspiration and seepage through the pile will be minimized by the low permeabili- U ty layer. p Comment: Several comments expressed concern about the pro posed geochemical treatment and suggested further study of this i portion of the remedy. n Response: The ROD incorporates a detailed study concerning the location, design, operation and short and long range environ mental effects of the passive treatment system proposed for mine portal discharges to the Telluride Valley prior to implementa 0 tion. Further, if the passive system alone proves not to suffi ciently reduce pollutant loadings to the San Miguel River, the ROD requires an active treatment plant or other suitable, cost-effective alternatives to be employed. -175- Q G p, u r~i Comment: One comment disagreed with the state's elimina- \J tion of a full-scale active water treatment facility for surface P waters flowing to the San Miguel River. p Response: Conventional water treatment was rejected for several reasons, including the size necessary to treat the large ) ! volumes of water from the entire mine; the environmental disturb- Jj P ance that would result from constructing such facility and laying U the associated piping system; the concerns about disposing the p large volume of sludge generated by the treatment facility; and the tremendous construction, operation and maintenance costs. Comment: Several comments wondered what would be done if tailings pile capping did not work as anticipated. (J Response: The ROD includes construction contingencies for p the tailings pile cap in the amount of $963,000 to correct diffi culties encountered with tailings pile capping has been incorpo- / I rated in the ROD. Additionally, establishment of permanent, P self-sustaining vegetation is required by the ROD. The LJ revegetation performance criteria are more fully detailed in the n ROD. Comment: One comment observed that the cost of the remedy nP in the PROD was less than the remedial alternatives considered in the Feasibility Study. Response: The state has selected a final Remedial Action Plan, consistent with CERCLA and the NCP, which effectively pro^ -176- P [ teets public health and welfare and the environment and which is P cost-effective. P Comment: One comment questioned whether the final cleanup p goals for the San Miguel River will differ from those for Red J Mountain Creek and the Uncompahgre River. p p Response; The stream classifications and numeric standards for the pertinent stream segments in the two river valleys do differ. In view of the different degrees of contamination encountered in the two valleys, the goals for each river valley are designed for that particular area and, therefore, are some what different. Comment; One comment requested the opportunity to have soil tested for contamination. J Response; The ROD includes a comprehensive soil testing program to further characterize soil concentrations of selected / I metals throughout the Town of Telluride, Soil testing may be afforded to Telluride residents through this program. p Comment: One comment questioned how the adequacy of p revegetation of disturbed areas would be determined. Response; The ROD, section 4.24, includes a more detailed analysis of revegetation requirements than was set out in the U PROD. Comment: Several comments suggested that the state con sider ultimate land use in developing the final Remedial Action n -177- Ll p Plan. Response; Remedial action must be consistent with CERCLA and the NCP. Under those laws, ultimate land use is not the cri teria which drives remedy selection. Rather, the remedy must prevent or minimize the release of hazardous substances, pollu tants or contaminants so that they do not migrate to cause sub stantial danger to present or future public health welfare or the environment. Comment; One comment suggested that remedy selection should account for an anticipated reduction in the blood lead level standard. Response; It is generally agreed in the scientific commu nity that no exposure to lead is healthy. However, the soil sampling and remediation required by the ROD should provide suf ficient protection of public health and welfare and the environ J ment, even if a lower blood lead level standard is set in the future. L Comment; One individual expressed concern that the diver- P sion of water over to the Treasury Tunnel would increase flood ^ flows on the Uncompahgre River. P Response; The diversion of water to the Treasury Tunnel will not significantly increase the flood flows on the J Uncompahgre River due to the minimal flows from the Treasury P Tunnel and the lag time between peak flows in the fiver and from -178- the tunnel. Comment; Several individuals asked about the possibility of constructing a passive mine water treatment system in the wet lands down valley of the Town of Telluride. n Response; The use of passive treatment using wetlands was p: evaluated. However, it was found that between 600 and 1000 P square feet of material would be required to treat 1 gallon per y minute of mine water. This would require 120 to 210 acres of n land. The efficiency of this system during the winter is ques L tionable and the construction of a piping system through town would be disruptive. fl\ fl AG File No. CHW8700770/LR Q 179 p p U ROD APPENDIX A P COMMUNITY RELATIONS PLAN y FOR THE IDARADO SITE This Community Relations Plan outlines the community rela P tions to be conducted regarding the Idarado site in San Miguel and Ouray Counties in Colorado. The State of Colorado has filed a lawsuit against Idarado Mining Corp., Newmont Services Ltd. and G Newmont Mining Corporation pursuant to the Comprehensive Environ mental Response, Compensation and Liability Act (CERCLA) 42 U.S.C 9601-9657 (1980). This plan will be updated and revised in response to events and/or citizen needs or concerns. I. INTRODUCTION The State of Colorado has conducted an environmental analy sis of the Idarado site. The results of this analysis have been reported in the two volume Remedial Investigation, and the one volume Feasibility Study reports. These reports are available for review at the locations listed in Appendix E (information re positories) attached hereto, and at both the Attorney General's office and the Colorado Department of Health, the addresses of which are in Appendix F attached hereto. The purpose of this Community Relations Plan is to estab lish a method to continue disseminating information to the public, and of receiving input from the public, regarding the Idarado site. Specifically, the state's goal is to inform the community regarding the nature of problems generated by the n Idarado site, the extent of contamination and the methods se lected to mitigate or eliminate environmental and health problems and risks. Much of this information has already been distrib uted, and is available at the established information reposito ries. II. BACKGROUND AND KEY ISSUES A. Site Location The Idarado Mining and Milling Complex is located in the San Juan Mountains of Southwestern Colorado. The site encom passes over 13 square miles of mountainous terrain in San Miguel Ouray, and San Juan Counties. For reference purposes, the site has been divided into two "districts," the Telluride District and the Red Mountain District. G p p p B. Lead Agency p The State of Colorado has initiated an action at this site without participation by the Environmental Protection Agency (EPA). The site is not listed on the EPA's National Priority list at this date. G C. Time Period Covered by Community Relations Plan This Community Relations Plan, effective immediately, shall P remain in effect until completion of the remedial work at the Idarado site. III. A. BACKGROUND AND HISTORY 1. Brief Site History Idarado Mining Company became active in the area in 1939, acquiring and consolidating most of their present holdings by 1956. Mining for zinc, copper, lead, silver and gold together with the milling of these metals continued until 1978. A Notice of Temporary Cessation of Operations by Idarado was received by the Mined Land Reclamation Division (MLRD) on August 21, 1978. Another Notice of Temporary Cessation was received by MLRD on July 17, 1986. To date, the MLRD has yet to receive a Notice of Closure for the Idarado site. The Idarado facilities encompass approximately 13 square miles including six tailings ponds on the Telluride side and five G on the Red Mountain side, waste rock and mine portal discharges on both sides and many miles of tunnels within the mountain. The majoiorr contaminants from the Idarado facility are heavy metals and me2taloid s that include; p J aluminum (Al) iron (Fe) arsenic (As) lead (Pb) barium (Ba) manganese (Mn) cadmium (Cd) molybdenum (Mo) chromium (Cr) nickel (Ni) copper (Cu) silver (Ag) zinc (Zn) Cyanide (CN) is also present. -2- GI In, P These contaminants are found in the tailings piles, mine p drainage waters and mine waste rock. The six tailings piles in the Telluride District contain approximately 12 million tons of P tailings. The largest of these piles lies adjacent to the P Telluride Town Park. The five tailing piles and other miscel laneous tailings in the Red Mountain District contain approxi- p mately 2 million tons of tailings. ^^ Red Mountain Creek is nearly devoid of all desirable forms of life. The Uncompahgre River is impacted for at least 15 miles I ' downstream of its confluence with Red Mountain Creek. The Ll Ridgway Dam Project, a major dam and reservoir with large recrea tional potential, will be impacted by metal loadings from Red y Mountain Creek. In addition to metal contaminants, organic hazardous sub- p stances were discovered onsite near the Pandora Mill at I Telluride. These were stored and/or disposed of outdoors in cor- ^ roded and broken containers that had leaked and contaminated onsite soils. A total of thirteen electrical transformers and 1 over 200 fifty-five gallon drums were discovered in September P 1985. P 2. Information on Clean-Up Plans The state completed its Remedial Investigation and issued r^ the report in April 1986. The Feasibility Study was released in P June 1986. Currently, the state is drafting the Record of Deci sion (ROD) which will outline and select a clean-up alternative which the state will pursue at trial in April 1987. P Idarado has conducted a yard clean-up, having hauled away some of the organic waste materials and sold used equipment and n machinery. Idarado has also issued their proposed remedial p action plan. Their plan consists primarily of stabilizing and revegetating the tailings ponds and cleaning-up organic wastes. IV. COMMUNITY INVOLVEMENT AND CONCERNS n Telluride and Ouray are the two primary communities which have been affected by the Idarado site and the litigation sur rounding that site. The Town of Telluride and its residents have been involved with the site for several years. During the 1970's the community urged Idarado to remedy the problem of blowing tailings. In response Idarado installed a sprinkler system. The community has continued to show interest in the site and in the litigation, -3- G r Both the state and Idarado have conducted public meetings lj in Telluride and Ouray, P V. COMMUNITY RELATIONS TECHNIQUES TO BE EMPLOYED p The goal of this Community Relations Plan is to keep the ; community advised regarding the nature and progress of the reme- ' dial process, f To date, the state has conducted several public meetings to C gain input from the communities regarding its Remedial Investiga tion and Feasibility Study reports. The state has also communi- P cated with the communities through press releases, letters and P via telephone. State officials have met with local officials on several occasions, as well. The state received both oral and p written comment on its reports through October 31, 1986. As a pj part of the ROD, all comments and questions received by October 31 are addressed in the state responsiveness summary. p In the future the state will continue to keep both communi- C ties informed of any significant events or findings. y Public officials (Appendix A), environmental and community J action groups (Appendix D) and interested individuals (Appendix B) will be specially advised. G VI. IDARADO CALENDAR April 1986 - Remedial Investigation report issued J June 1986 - Feasibility Study report issued November 15, 1986 - State's economic damage report issued P February 9, 1987 - PROD issued U March 17, 1987 - ROD issued April 13, 1987 - Trial AG File No, DHW8606966/BP -4- n u n APPENDIX A PUBLIC OFFICIALS Bob Duprey, Waste Management Director EPA 999 18th Street Denver, CO 80202 293-1720 p u Dick Krueger. U,S, Fish and Wildlife Service 52925 1/2 Rd., Suite B 113 G Grand Junction, CO 81505 G Ellie Towns Jud Wiebe P U.S. Forest Service P 11177 W. 8th Lakewood, CO 80225 Max Dodson Waste Management Director EPA 999 18th Street Denver, CO 80202 Q 293-1542 y Michael A. McGeehin y Public Health Advisor Superfund Branch p-i Waste Management Division U.S. EPA Region VIII L 999 18th Street, Suite 1300 Denver, CO 80202 P P n Region 10 District 10 Regional Planning Commission David Anderson 107 So. Cascade P. 0. Box 371 Montrose, CO 81401 249-9638 Regional Director Regional U.S. Fish - Wildlife Service P Denver Federal Center P.O, Box 25486 C Denver, CO 80225 P 236-7920 P U y LJ 1 P -2- G U,S. SENATE Senator William Armstrong ATTN: Mae Snowden 311 Steele Street Environmental Issues Suite 103 Washington, D,C, Denver, CO 80206 398-0831 Room SH 528 United States Senate Washington, D,C 20510 P (202) 224-5941 Senator Timothy Wirth ATTN: Jim Martin 3489 W, 72nd Avenue #112 Environmental Westminster, CO 80030 Liaison 650-7900 G U,S, Senate Washington, D,C. 20510 G n P P -3- u U.S. HOUSE OF REPRESENTATIVES Third Congressional District Representative Ben Campbell P.O. Box 638 Ignacio, CO 81137 P 563-4623 c J G P P P P Q -4- u COLORADO - GENERAL ASSEMBLY - SENATE sixth Senatorial District Senator Robert DeNier 2707 Colorado Ave. Durango, CO 81301 247-0149 State Capitol Room 224 Denver, CO 80203 866-4866 n COLORADO - GENERAL ASSEMBLY - HOUSE OF REPRESENTATIVES U Fifty-eighth Congressional District n Representative Margaret Masson P 6433-1/2-4200 Dr. Crawford, CO 81415. 921-3621 State Capitol Room 242 Denver, CO 80203 866-2939 Q Fifty-ninth Congressional District P P Representative Jim Dyer 127 Oak Dr. DW II Durango, CO 81301 259-1942 State Capitol Room 220 -5- P Denver, CO 80203 866-2914 ~] u P n -6- PUBLIC OFFICIALS/OURAY Ouray County P Ouray County Clerk Addie Sim p P.O. Bin C L Ouray, CO 81427 325-4961 G Ouray County Administrator Pat O'Donnell P.O. Box 572 Ouray, CO 81427 325-4706 Ouray County Commissioners; Howard Williams, Chairman Kenneth Williams Bob Larson P. O. Bin C Ouray, CO 81427 325-4961 City of Ouray: City Council William D. Fries, Mayor G Michael J. Kern Joseph M. Mattivi Richard B. Spalding Lindy G. Reed P.O. Box 468 Ouray, CO 81427 -7- G Ouray City Clerk Ms. Lucy Zeller P.O. Box 468 Ouray, CO 81427 325-4323 Ouray Planning Commission; Joanne Feddel Drawer K Elaine Ricker Box 22 Jack Shoennebaum Chairman, Box 354 p Ouray, CO 81427 J Ouray City Attorney p John R. Kappa L P.O. Box 790 Montrose, CO 81402 L City Administrator P David Vince U P.O. Box 468 Ouray, CO 81427 p -8- n LJ PUBLIC OFFICIALS/TELLURIDE LJ UP Council Members I B.J. (Chip) Lenihan, Mayor i Jim Bedford Dave Erickson Bob Levy Steve Patterson P Jim Pettegrew Jim Russel J P.O. Box 397 ! Telluride, CO 81435 ' 728-3851 Gary Hickcox Town Manager P.O. Box 397 Telluride, CO 81435 Bill Frownfelter Town Engineer P.O. Box 397 Telluride, CO 81435 Commissioners - San Miguel County; n Randall Higgenson U P. 0. Box 1104 Telluride, CO 81435 Linda Luther p P. 0. Box 126 p Telluride, CO 81435 Raymond Snyder P. 0. Box 1398 P Telluride, CO 81423 P -9- Telluride Environmental Commission J Nick Kirsch Town Hall Telluride, CO 81435 728-3851 June Nepsky, County Nurse P. 0. Box 548 Telluride, CO 81435 Larry Larson Director of Planning San Miguel Co. Planning Commission P. 0. Box 548 Telluride, CO 81435 Telluride Planning Commission P. O. Box 397 Telluride, CO 81435 ^^ Dan Wilson San Miguel County Attorney P.O. Box 791 Telluride, CO 81435 728-3879 Steve Johnson Town Attorney P.O. Box 397 Telluride, CO 81435 r P -10- p APPENDIX B INTERESTED GROUPS AND INDIVIDUALS GROUPS Trout Unlimited 1557 Ogden Street Denver, CO 80217 Western Colorado Congress LJ P. 0. Box 472 Montrose, CO 81402 p 249-1978 p Colorado Mining Association David R. Cole 1500 Grant Street Suite 330 D Denver, CO 80203 B.P.O.E. 201 W. Colorado Ave. Telluride, CO 81435 728-3385 San Miguel Co. Historical Society p P. 0. Box 1357 Telluride, CO 81435 728-3344 p Telluride Institute, Inc. Ms. Pamela Lifton-Zoline or Mr. John Naisbitt 210 W. Colorado Ave. Telluride, CO 81435 728-4981 -11- Telluride Ski Resort, Inc. p P. O. Box 307 LJ Telluride, CO 81435 728-3041, 728-4431 LJ Telluride School District P Cleve Penberthy, Superintendent L P. O. Box 187 Telluride, CO 81435 B.P.O.E. 492 3rd St. Ouray, CO 81427 325-4510 P Ouray Chamber of Commerce P. O. Box 145 n Ouray, CO 81427 I 1 325-4746 Ouray County Economic Improvement League Charles Rahm P. O. Box 401 Ridgway, CO 81432 Roger Henn Ouray Co. Historical Society P. O. Box 151 Ouray, CO 81427 325-4876 Ouray School District Scott Purdy, Superintendent P. 0. Box N Ouray, CO 81427 League of Women Voters of Colorado Tess McNulty, Water Section 2160 Vassar Dr, Boulder, CO 80303 -12- Montrose League of Women Voters Barbara Krebs, President P. 0, Box 776 Montrose, CO 81401 Grand Junction League of Women Voters Pat Carney, President 533 Dodge St, Grand Junction, CO 81504 Durango League of Women Voters Judy Lent, President 2710 New Mexico Ave, U Durango, CO 81301 Individuals Dr, Howard Kornfeld P, 0, Box 1748 Telluride, CO 81435 Gl Mark Fisher, Attorney P P. 0, Box 1737 Telluride, CO 81435 n Dr, Jeff Berkosky, M,D. P. O. Box 2022 Montrose, CO 81402 242-0731 Ruth Siemer P. O. Box 415 Ouray, CO 81427 -13- APPENDIX NEWS MEDIA Newspapers The Denver Post 650 15th Street Denver, CO 80202 820-1010 LJ The Grand Junction Daily Sentinel Attn: Nancy Lofholm p P. 0. Box 668 p Grand Junction, CO 81502 242-5050 1 The Montrose Daily Press P. 0. Box 850 P Montrose, CO 81402 LJ 249-3444 The Rocky Mountain News G P. 0. Box 719 Denver, CO 80201 892-5000 Steve Klein, Publisher GJ "On the Record" 1125 17th St., #1940 P Denver, CO 80202 P 585-9100 The Telluride Times Attn: Tony Daranyi P. 0. Box 367 Telluride, CO 81435 728-4301 -14- P Q UJ P The San Miguel Journal J Attn; Art Goodtimes P. 0. Box 1765 Telluride, CO 81435 728-4488 ~1 The Ouray County Plaindealer J The Ridgway Sun P. 0. Box 607 P Ouray, CO 81427 325-4462 u u Radio Stations P J KEXO ~ AM Radio P.O. Box 2450 Grand Junction, CO 81502 p 243-1230 U KJOL/FM/ED Owen G. Howard, General Manager 2711 Unaweep Ave. Grand Junction, CO 81503 p KKSK — FM y KWBC — AM Floyd McMillan P 2018 So. Townsend Ave. Montrose, CO 81401 n KMSA/FM/ED J Arne McConnell General Manager n P. 0. Box 2647 P Mesa College Grand Junction, CO 81502 P -15- KOTO ~ FM Bob Brickell P. 0. Box 1069 Telluride, CO 81435 728-3206 KQIL/AM KQIX/FM Lindan Skinner/Russ Schuckmann P. O. Box 340 Grand Junction, CO 81502 247-7800 KREX — AM/FM Jeff Frye — News Manager P. O. Box 789 Grand Junction, CO 81501 242-5000 p p KSTR ~ AM Radio Paul Massa, News 910 Main Street P. 0. Box 1120 Grand Junction, CO 81502 KURA ~ FM Scott Wagner Todd Pace 318 6th Ave. Ouray, CO 81427 325-4471 KSTR/KWDE ~ FM Radio 112 W. Main G Montrose, CO 81401 (249-8007 - Grand Jet.) -16- P Ht TV Stations KCNC -- Channel 4 1044 Lincoln St. Denver, CO 80203 830-6397 KJCT — TV Henry Chus, News Director Gl Foresight Circle P P. 0. Box 3788 n Grand Junction, CO 81502 KMGH — Channel 7 123 Speer Blvd Denver, CO 80203 832-0177 KREY — TV Rick Von 614 No. First Montrose, CO 81401 249-9601 Q KUSA -- Channel 9 1089 Bannock Street n Denver, CO 80204 u 893-4499 KUSA — Channel 9 Western Slope Petroleum Building 2754 Compass Drive, Suite 363 Grand Junction, CO 81506 Attn: Dan Dennison — Chief Correspondent Western Slope Bureau G 242-1999 Gl KWGN — Channel 2 JG 6160 So. Wabash Way Denver, CO 80111 -17- TCTV (Telluride Community Television) Tom Farrell G P. 0. Box 1521 Telluride, CO 81435 728-3838 P G -18- p p APPENDIXD ENVIRONMENTAL AND COMMUNITY ACTION GROUPS P ' ! P I Colorado Environmental Coalition P Elizabeth Otto P 2239 E. Colfax Avenue Denver, CO 80206 J 393-0466 p Colorado Publie Interest Research Group (CoPIRG) 1 Casey Padgett ^ 1725 Gilpin Denver, CO 80218 I 355-1861 p Colorado Whitewater Association P 7600 E. Arapahoe Ave. Englewood, CO 80112 P Colorado Wildlife Federation 1560 Broadway, Suite 895 Denver, CO 80202 830-2557 P Environmental Defense Fund Dan Luecke p Attn: Melinda Kassen 1405 Arapahoe Ave. Boulder, CO 80302 _ 440-4901 Wilderness Society 1720 Race Denver, CO 80206 388-5801 Friends of the Earth Ms. Connie Albrecht \ P. 0. Box 728 GJ Palisade, CO 81526 -19- n P National Wildlife Federation Norman Dean, Director and Counsel Toxic Substances Division 1412 16th Street, N.W. Washington, D.C 20036 ' ! 1 Tom Lustig G Fleming Law Building P. 0. Box 401 Boulder, CO n 444-2950 Sierra Club Rocky Mountain Chapter Ms. Julie Anderson 2239 E. Colfax Ave. Denver, CO 80206 321-8292 G P Q -20- p APPENDIX E INFORMATION REPOSITORIES p Mesa County Library Lynn Bragdon 530 Grand Ave. Grand Junction, CO 81501 243-4442 Montrose Regional Library p Zerma Kinkel u 434 So. First & Uncompahgre St. Montrose, CO 81401 249-9656 p Ouray Public Library p Ouray Town Hall 320 6th Ave. p P.O. Box 468 1 Ouray, CO 81427 ^ 325-4616 San Miguel County Public Library 127 So. Spruce P. 0. Box 633 Telluride, CO 81435 728-4519 p Telluride Town Hall P. 0. Box 397 Telluride, CO 81435 G -21- APPENDIX F GOVERNMENT STAFF G Colorado Attorney General's Office Duane Woodard, Attorney General p Howard Kenison, Deputy Attorney General L Kent Hanson, First Assistant Attorney General Charlotte Robinson, Assistant Attorney General p Susan Keller, Legal Assistant 1560 Broadway, Suite 250 ^ Denver, CO 80202 866-4344 Colorado Department of Health G Thomas F. Vernon, M.D., Executive Director p Thomas Looby, Assistant Director Ellen Mangione, M.D., Acting Director ~j Gary Broetzman, Assistant to the Director L Paul Ferraro, WQCD Director Rick Karlin, WQCD Section Chief p Disease Control and Environmental Epidemiology Division J Donald H. Simpson, Mined Land Reclamation Specialist 4210 East 11th Avenue p Denver, CO 80220 1 320-8333 G Q AG Alpha No. LW HW HXWO AG File No. CHW8700770/1LR -22- |987 1989 1990 1991 1992 Am uw JUt M. KT OCT rp/ KC FaHMiitnwr m u. im so ca toi ta MW JIM JU. MM.aEPOCT NOVOK iuvjuiju.«MserocTNOvocc FEB UM wn SCP OCT NOV OCC I I L -J 1 I L _J 1 I I I I I \ I \ L J I l_J \ L J I I L J I- -I I I I 1 I I L J \ I I L J I L OCMIiH INVnTI8«T10N» -| ITATl , wiEutt wjuit • Sicca. I I 1 ST*TE ,. REVIEW FINAL PLANS B SPECS. H •TWE .REVIEW » AP[PI>0VI>L WHOLE SITE PLAN . I< VEAR CONSTRUCTION STATE CCNSTKUCTIOtl REPORT -I REVIEW , 2"* YEAR CONSTRUCTION CONSTWJCnON REPORT STATE -I _RErtEW_. H 3" YEAR CONSTRUCTION I CONSTRUCTION REPOHT i i^Vi, ^ I J..!?-Irr_.| 4'" » PINAL YEAR CONSTRUCTION FINAL STATE PINAL CERTIFICATION REPORT -iREy^EREVIEW I •"ANO ' APPROVAL PROJECT COUPimON JANUARY I, 1992 COMPONENT ., COMPLETE REMEDUriON REMOVAL, DILUTION. COVERINQ TELUJRIDE SOILS .CONSOLIDATION OF PILES, RUN-ON CONTROL, CONTtXIRING TAILINGS COUfLCTC CAP CONSTRUCTION, FUXX> PROTECTION ''REWEDIAriON CAP CONSTRUCTION REVEGETATION REVEGETATION, IRRIGATION , DIVERT RUN-ON DIVERT RUN-ON COMPLETE I STREAM REMOVAL ROIEOIAnaN WASTE ROCK C^ PILES PLUG B DIVERT INFLOWS MINE PORTAL RED MOUNTAIN CREEK RESERVOIR, ^canpi.^ir • DIVERT RUN-ON. LIMESTONE CHARGING RED MOUNTAIILCREEK FLOWS ROYER GULCH INFILTRATION PONDS ^.-'^ fffMEOMnOW COUflSJI MARSHALL CREEK /-naiaunKH HYDROLOGIC INFILTRATION PONDS HABITAT ENHANCEMENT STREAM FISH STOCKING IMPROVEMENTS FINAL REMOVAL OF ORGANICS rrt.57F AND CONTAMINATED SOIL - VERIFICATION TESTING , REMOVAL OF SUILCINGS MILL SITE DECOMMISIONINO