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DIVISION INFORMATION |
Hazardous Materials and Waste Management Division
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| Site Photo | Interactive Data Reports |
| Alamosa River Watershed Restoration Master Plan Draft Executive Summary | |
| Summitville Mine Sitewide Record of Decision (ROD) 2001 | |
| Five-Year Review 2005 | |
For questions or comments on the Summitville Mine Site, contact:
Austin Buckingham,
State Project Manager
303-692-3435
(888) 569-1831 ext 3435 toll-free
Marilyn Null,
State Community Involvement Coordinator
(303) 692-3304
(888) 569-1831 ext 3304 toll-free
or
Ken Wangerud, EPA Remedial Project Manager
303-312-6703
This 1,400-acre site is located in Rio Grande County, approximately 18 miles southwest of Del Norte. The mine site is in the San Juan Mountains at an elevation of 11,500 feet, surrounded by the Rio Grande National Forest. The Alamosa River and its tributaries flow from the site through forest and agricultural land in Rio Grande and Conejos Counties and past the San Luis Valley towns of Capulin and La Jara. The Terrace Reservoir, used for irrigation, is on the Alamosa River 18 miles downstream from the site.
Gold and silver mining began at Summitville around 1870. The latest mining operator, Summitville Consolidated Mining Corp., Inc. (SCMCI), mined the site from July 1986 through October 1991 and abandoned the site in December 1992. The company opened a pit heap leach gold mining operation, using cyanide to extract the gold. The EPA Emergency Response Branch assumed responsibility of the site on December 16, 1992. The site was placed on the National Priorities List of Superfund sites on May 31, 1994.
The chemicals of concern are heavy metals (copper, cadmium, manganese, zinc, lead, nickel, aluminum, iron) on-site and in the acid mine drainage.
Mining operations deforested and denuded the area, removing topsoil and vegetation on most of the land area at Summitville, which led to large-scale erosion. Because of the highly mineralized character of the site, almost all exposed earthen materials are capable of acid generation. This acid mobilizes the variety of metals that contaminate the Alamosa River system below the site. Surface water quality downstream of the mine has been substantially degraded by low pH (acidic water), elevated dissolved solids and heavy metals (especially copper).
Human exposure to these contaminants is limited, since no one lives within two miles of the site nor uses the immediately surrounding groundwater for drinking. Drinking water wells for San Luis Valley residents living more than 20 miles downstream of Summitville have been sampled on numerous occasions and have never shown elevated metals concentrations associated with the site. In 1997, the Agency for Toxic Substances and Disease Registry (ATSDR) released a Public Health Assessment that classified the Summitville site as no apparent public health hazard.
Ecological impacts from site contaminants are considerable, as the Alamosa River system below Summitville cannot currently support aquatic life. Studies have found potential adverse effects to agriculture and livestock from regular use of Alamosa River water. Preliminary results have indicated some uptake of metals in livestock and some agricultural soil degradation from irrigation. However, in both cases the effects have not been of a level that affects the viability of local farm products or impacts the food chain.
Since 1992, EPA and the Colorado Department of Public Health and Environment have initiated several interim projects designed to slow the amount of acid mine drainage coming from the site. These interim projects have included: detoxifying, capping and revegetating the heap leach pad; removing waste rock piles and filling the mine pits; plugging the adits or underground mine entrances; and expanding the water runoff holding ponds, as well as operating a water treatment plant on-site.
The Colorado Department of Public Health and Environment led the largest interim measure to be implemented: Sitewide Reclamation and Revegetation. In addition, the Department led the Remedial Investigation and Feasibility Study (RI/FS) for the site, which began in 1998. The study evaluated the effectiveness of the interim measures that have been completed or that remain on-going at the site, and determined what final construction projects or long-term measures must be added in order to wrap up the Summitville cleanup in the future. The study culminated with a site-wide Record of Decision (ROD) issued in the fall of 2001.
Along with ongoing operation and maintenance of the site, current activities include improvements to the Wightman Fork Diversion, Summitville Dam Impoundment dam and spillway channel, as well as an installation of Micro-Hydro-Power to reduce the site's dependence on line energy power. With the 2007 changes to the Alamosa River underlying aluminum standards, the EPA and Colorado Department of Public Health and Environment plan to begin design of a new Water Treatment Plant, with construction estimated to start in 2010.
History 1992 to Present
| 1992-1994 |
EPA and Colorado Department of Public Health and Environment emergency response at abandoned Summitville Mine |
| 1994 |
Interim Record of Decision: 1: water treatment plant; 2: Cropsy Waste Pile, Beaver Mud Dump, Summitville Dam Impoundment and mine pits; 3. Heap Leach Pad; and 4. reclamation |
| 1994-1995 | Heap Leach Pad detoxification |
| 1994 | Reynolds Adit bulkhead |
| 1996 |
Cropsy Waste Pile, Beaver Mud Dump, Summitville Dam Impoundment and mine pit closure |
| 1996-2000 | Modification to the existing water treatment plant |
| 1994-1998 | Cropsy Valley restoration and revegetation |
| 1998 | Heap Leach Pad cap complete |
| 1998 | Completion of Heap Leach Pad, North Waste Dump |
| 1998-2001 | Sitewide Remedial Investigation and Feasibility Study |
| 2001 | Sitewide Record of Decision (ROD) |
| 2002 | Complete sitewide reclamation |
| 2004 | Complete water treatment plant design |
| 2004-2005 | Complete contaminant source collection structures |
| 2005 |
Colorado Department of Public Health and Environment assumes lead role for wastewater treatment plant and site operation and maintenance |
| 2006 | Rule change before the Water Quality Control Commission for the Alamosa River |
| 2008-2009 | Wightman Fork and Summitville Dam Impoundment improvement, installation of micro-hydro-power |
| 2010 est. | Begin construction of new water treatment plant |
Alamosa River Watershed Restoration Master Plan
In preparation for issuing the Solicitation for Project Proposals, the Federal and State Cooperative Trustee Council contracted with MWH Americas, Inc. to write the "Alamosa River Watershed Restoration Master Plan" (Master Plan) dated July 2005. The Trustee Council, authorized under the Comprehensive Environmental Response, Compensation and Liability Act (December 1980), is seeking to restore natural resources harmed in connection with impacts from the Summitville Mine, using natural resource damages (NRD) obtained in settlement from a responsible party. The Master Plan summarized current environmental conditions and developed restoration solutions to the identified problems in the Alamosa River basin, which will lead to a healthier watershed. The scope of the Master Plan includes the entire watershed, with the exception of the Summitville Mine Superfund Site. The focus of the Master Plan included:
Specific projects were identified and ranked and then combined into a watershed restoration strategy, with the intention of implementing the best combination of projects to obtain the watershed restoration vision.
The Trustee Council determined that it would allocate a total of $5 million in damages in two phases, in order to ensure the success of restoration projects in addressing the Council's goals, the effectiveness in using the available funds, and to maximize access to matching funds. Phase I would allocate up to $2.5 million, one half of which ($1.25 million) would come from the State account and one half ($1.25 million) from the Federal account.
The following provides a project summary and description. The work group recommends approval for funding the projects presented with consideration of contingencies.
Alamosa River In Stream Flow Project
The Alamosa River In Stream Flow Project combines two of the key projects identified in the Alamosa River Watershed Restoration Master Plan and Environmental Assessment. The two projects are intended to accomplish a central objective of the Master Plan - improve the sustainability of flows in the Alamosa River downstream of Terrace Reservoir and upstream from the Terrace Reservoir spillway channel. The In Stream Flow Project involves:
The Alamosa River In Stream Flow Project is proposed as a two-phase project. Phase I includes purchasing one or more senior irrigation water rights, transferring the water rights to the Colorado Water Conservation Board in-stream flow program through water court, and designing Terrace Reservoir spillway improvements. Phase II entails renovating the reservoir spillway, storing the in-stream flow water rights in Terrace Reservoir, and releasing the water rights to restore healthy flows in the Alamosa River. The entire project will improve the magnitude and duration of stream flows in the Alamosa River below Terrace Reservoir, improving environmental, water resource and recreation values and thereby restoring and replacing resources damaged in the Alamosa River Watershed by the Summitville Mine project.
The proposal by the Alamosa River Keepers is for a project valued at $7,089,000 that is, for both Phases I and II. Phase I, valued at $4,520,500, requests $1,774,500 in Natural Resource Damage Assessment (NRDA) funds and includes $2,746,500 in matching funds. Phase II, valued at $2,569,000, requests $660,000 in Natural Resource Damage Assessment funds and includes $1,909,000 in matching funds. Because of the costs, complexity and time requirements of this project, the project proponents were asked to provide a comprehensive plan including both funding phases.
Alamosa River Watershed Restoration
The proposal by the San Luis Valley Resource Conservation and Development Council is for a project valued at $1,083,800, comprising $500,000 in Natural Resource Damage Assessment funds and $624,300 in matching funds.
The Alamosa River Watershed Restoration Foundation is a volunteer group of nine local landowners that formed in 1995 in response to serious problems on the Alamosa River. These problems include:
The following conditions have caused severe degradation of the river, and have impacted those who depend on it for their livelihood:
The Alamosa River Watershed Restoration Foundation seeks to remedy these impacts by continuing work that began in 1999 when the Foundation started restoring the river channel, confining the river between stable banks, and enabling more natural river meanders. The project provides riffle-pool-glide sequences that will restore areas for fish habitat and includes revegetation in selected areas in order to help restore the riparian corridor. As the river water begins to move in more historically natural ways, cottonwoods, willows, alders and other plants will have the conditions they need to replenish. As the riparian corridor returns to a healthy system, aquatic species returned to the river can survive.
The work scheduled for this section of the project includes approximately 2.6 miles of river corridor, located between County Road 8 (just north of the Post Office in the town of Capulin) and County Road 10 to the east.
Public Land Alamosa River Watershed Restoration
The proposal by the US Forest Service (Rio Grande National Forest) is for a project valued at $160,650, requesting $80,325 in Natural Resource Damage Assessment funds with $80,325 in matching funds.
The project will restore the Alamosa River and its environs from a point just above the confluence with Wightman Fork down to the Alamosa River Campground. The project includes five separate reaches on the river. Four areas with actively eroding stream banks will be stabilized and wetlands adjacent to the Alamosa River reestablished. Using rock constructed cross-vanes and j-hooks to restore aquatic habitat, the project will reconstruct the river from its current braided condition into a single thread channel.
EPA
Summitville Webpage
Agency
for Toxic Substances and Disease Registry (ATSDR) Public Health
Assessment
