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1. Introduction
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1.1 Background
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Site Number: |
109H |
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Contract Number: |
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D.O. Number: |
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Action Memo Date: |
10/11/2007 |
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Response Authority: |
CERCLA |
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Response Type: |
Non-Time-Critical |
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Response Lead: |
EPA |
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Incident Category: |
Removal Action |
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NPL Status: |
Non NPL |
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Operable Unit: |
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Mobilization Date: |
7/5/2010 |
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Start Date: |
7/6/2010 |
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Demob Date: |
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Completion Date: |
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CERCLIS ID: |
WAN001002309 |
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RCRIS ID: |
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ERNS No.: |
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State Notification: |
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FPN#: |
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Reimbursable Account #: |
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1.1.1 Incident Category
Inactive hard rock mine and mill.
1.1.2 Site Description
The Anderson-Calhoun Mine & Mill Site is a former lead and zinc mine and mill. Mineral exploration, mining, and milling activities were conducted between 1910 and the early 1980s. Historic mining-related features at the Site include two small open pits used to mine zinc ores, the remains of a flotation mill used to process zinc and barite ores, a tailings impoundment used to contain the residues from the processing of zinc and barite ores, and associated mining and milling infrastructure. The mill has generally been abandoned since the barite processing ended in the early 1980s.
1.1.2.1 Location
The Anderson/Calhoun mine and mill site is located in Stevens County, Washington. The entire Site is approximately 200 acres; the area affected by former mining and milling operations is approximately 92 acres. The area near the Site is rural ; surrounding activities include agriculture, forestry, and livestock grazing. There are several single-famility residences nearby the Site. The current owner of the Site has been identified.
1.1.2.2 Description of Threat
1.1.3 Preliminary Removal Assessment/Removal Site Inspection Results
EPA first identified the Site in 2001 as part of the Preliminary Assessment and Site Inspection (PA/SI) for Upper Columbia River Mines and Mills in Stevens County. The PA/SI inventory of the Site identified numerous 55-gallon drums, oil-filled transformers and other electrical equipment, a fuel storage tank, and other structures and equipment associated with mining and milling activities. The PA/SI also documented evidence of elevated concentrations of metals in the tailings pile and in soils near the former mill.
In 2002, EPA conducted a removal evaluation and determined that the release or threat of release of hazardous substances at the Site presented an imminent and substantial endangerment to public health and the environment.
To mitigate imminent human health and ecological threats from the release or threatened release of hazardous substances, EPA implemented a time-critical removal action at the Site between October 27 and November 3, 2002. The time-critical removal action involved the removal and disposal of containers and drums containing hazardous and non-hazardous substances, and the removal and disposal of transformers and other electrical equipment containing polychlorinated biphenols (PCBs). EPA completed a Removal Action Report in March 2003 that identified potentially responsible parties (Combustion Engineering, Goldfield Corporation, and Blue Tee Corporation) at the Site and concluded that further assessment was necessary to determine if the Site warranted additional response action.
In August 2004, EPA entered into an agreement with the potentially responsible parties to prepare an Engineering Evaluation and Cost Analysis (EE/CA) and to reimburse EPA’s EE/CA oversight costs. The final EE/CA report, completed in 2007, concluded that the lead-zinc and barite tailings at the Site presented unacceptable human health and ecological risks. The constituents of concern identified at the Site included barium, cadmium, copper, lead, selenium and zinc. In an Action Memorandum dated 11 October 2007, EPA selected a non-time critical removal action to address the threats to human health and the environment identified in the EE/CA. The proposed non-time critical removal action calls for the excavation of tailings located next to the mill building, as well as a small amount of oil-stained and other contaminated soils, and the consolidation and capping of these materials, along with other cleanup actions.
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2. Current Activities
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2.1 Operations Section
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2.1.1 Narrative
EPA, START, and ERRS mobilized to the Site the week of 5 July 2010 to begin cleanup activities which are expected to require 8 weeks.
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2.1.2 Response Actions to Date
ERRS has improved site infrastructure and installed erosion and sediment control features. ERRS continues to excavate mine waste contaminated materials and pertoleum-contaminated soils from the mill area and to transport and consolidate these materials at the on-site tailings impoundment, as well as maintain erosion and sediment control features. START continues to monitor air and surface water for short-term construction-related impacts and to guide excavation of contaminated materials.
2.1.3 Enforcement Activities, Identity of Potentially Responsible Parties (PRPs)
Three PRPs were identified for the Site. EPA entered into a settlement agreement with Combustion Engineering, Inc. and Goldfield Corporation in April 2009. EPA also entered into a settlement agreement with Blue Tee Corporation in February 2010 for payment of response costs for implementation of the selected cleanup action.
2.1.4 Progress Metrics
| Waste Stream |
Medium |
Quantity |
Manifest # |
Treatment |
Disposal |
| Barium, cadmium, lead, selenium, zinc |
Mine waste contaminated soil and mill tailings |
Estimated 15,000 cubic yards around mill structures; estimated 1,000,000 cubic yards in impoundment |
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Excavation and consolidation |
All materials will be consolidated beneath a protective barrier constructed over the existing on-site impoundment |
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2.2 Planning Section
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2.2.1 Anticipated Activities
Continued excavation of contaminated materials and transport of the materials to the on-site repository; construction of a protective barrier over the consolidated materials; continued maintenance of site infrastructure and erosion and sediment control features; continued air and surface water monitoring for short-term construction-related impacts; and grading and stabilization of disturbed areas.
2.2.1.1 Planned Response Activities
As discussed above.
2.2.1.2 Next Steps
As discussed above.
2.2.2 Issues
None.
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2.3 Logistics Section
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N/A
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2.4 Finance Section
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No information available at this time.
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2.5 Other Command Staff
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2.5.1 Safety Officer
Site safety plans have been prepared and are available on-site. Daily safety briefings are conducted.
2.6 Liaison Officer
N/A
2.7 Information Officer
2.7.1 Public Information Officer
N/A
2.7.2 Community Involvement Coordinator
N/A
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3. Participating Entities
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3.1 Unified Command
N/A
3.2 Cooperating Agencies
EPA is working closely with US Fish & Wildlife Service and with Washington State Department of Ecology.
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4. Personnel On Site
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1 - EPA OSC
2 - START (TechLaw)
12 - ERRS (EQM)
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5. Definition of Terms
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N/A
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6. Additional sources of information
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6.1 Internet location of additional information/report
N/A
6.2 Reporting Schedule
The next POLREP will be submitted on or about 13 August 2010.
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7. Situational Reference Materials
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N/A
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