Region 8
Serving Colorado, Montana, North Dakota, South Dakota, Utah, Wyoming and 27 Tribal Nations
Clark Fork River Operable Unit
| Site Information |
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Site Description and
Cleanup Progress Site Risk Site Documents Community Involvement Map of CFR Basin Contacts |
Site Type: Active NPL
City: Deer Lodge
County: Powell
EPA ID#: MTD980717565
NEW:
- Feb 12, 2008 -- Clark Fork River Consent Decree (PDF, 1 page, 86 kB)
- Feb 7, 2008 -- Atlantic Richfield Company agrees to pay $187M for Clark Fork River cleanup (Press Release)
- ARCO Settlement Fact Sheet
- RipES: A Remedial Design Tool
Site Description and Cleanup Progress
The Milltown Reservoir / Clark Fork River Superfund Site is divided into three Operable Units: Clark Fork River, Milltown Water Supply, and Milltown Reservoir Sediments. The focus of this update is the Clark Fork River Operable Unit.In 1992, EPA designated the Clark Fork River, from the outlet of Warm Springs Ponds (see detailed map) to upstream of the Milltown Reservoir, as a distinct operable unit of the Milltown Reservoir Superfund Site. An investigation into the nature and extent of contamination of the Clark Fork River began in 1995. EPA notified Atlantic Richfield Company of its liability and entered into a Consent Order with ARCO to conduct a Remedial Investigation and Feasibility Study. In 2000, EPA ordered ARCO to conduct a time-critical removal action to address immediate human health risks for residents of Eastside Road in Deer Lodge.
EPA released a Proposed Plan for cleanup in August 2002. The cleanup proposal included a combination of removal and in-place treatment of tailings and contaminated soil, followed by revegetation. Stabilization of eroding streambanks is an important part of the remedy, because they contribute approximately 60% of the pollutants to the river. Remedial actions are proposed primarily for Reach A (Warm Springs Ponds to Garrison), and parts of Reach B (Garrison to Drummond). EPA invited public comment on the Proposed Plan for 120 days and received nearly 2,000 comments. A Record of Decision or ROD was signed in April of 2004.
EPA concluded settlement discussions with ARCO and the State of Montana in an effort to settle cleanup responsibilities and costs associated with the remedy proposed in the ROD. The settlement also involves the State's natural resource damage plan, which will be implemented along with EPA's selected remedy. The Department of Interior's federal restoration plan, which addresses the Grant-Kohrs Ranch National Historic Site and BLM land, will also be implemented.
Recognizing the importance of moving forward with cleanup on the Clark Fork River while the settlement negotiations continued, EPA initiated pre-remedial design level evaluation of the Clark Fork River OU using the Riparian Evaluation System (RipES) tool. This tool was developed as part of the ROD. The RipES work began with aerial photography of the river in May of 2006. Slickens and other impacted areas, and cultural features like roads and fences, were drawn onto the aerial photographs, and a base map was generated. In the years 2006, 2007 and 2008, EPA and its contractors verified this information on the ground, using more precise survey techniques. Some limited soil sampling was also performed to establish the depth and magnitude of contamination. The results of this effort provides EPA with an oversight tool that can be used to evaluate future Remedial Design and Remedial Action. Furthermore, application of RipES has generated information needed to develop both preliminary and final site-specific designs for individual properties.
Landowner input will be solicited so that issues such as fencing, livestock watering, and agricultural practices can be identified for consideration in developing site specific design plans. Data tables and maps will be developed in an electronic format that will eventually be available through the internet.
Now that enforcement proceedings are completed and some RipES information is available, Remedial Design will begin in 2008, and then Remedial Action construction will implement the selected remedy. The Montana Department of Environmental Quality (DEQ) will implement the remedial design and remedial action, with EPA and National Park Service help and oversight.
Site Risk
The site risks for the Clark Fork River OU are described for both human health and environmental receptors. Contaminants present in the Clark Fork OU are from historic mining and smelting processes upstream of the Clark Fork River. Contaminants of concern include arsenic, cadmium, copper, lead, and zinc. Copper is the primary contaminant associated with environmental risk, and arsenic is the primary contaminant associated with human risks. Concentrations of metals and arsenic are quite variable within the floodplain of the Clark Fork River. In general, studies have concluded that the human health risks are low enough to be considered "acceptable", but the ecological risks are high enough to be considered "not acceptable".Site Documents
Note: all of the documents referenced below are Adobe PDF filesAbout PDF files
Consent Decree for the Clark Fork River Operable Unit Site
On February 7, 2008, a Consent Decree for the Clark Fork River Operable Unit Site was lodged with the Federal District Court in Montana. Public comments will be accepted on the Consent Decree during a 60-day Public Comment period. The Consent Decree provides the structure for how Atlantic Richfield will "cash out" of it's cleanup responsibilities by providing over $168 million to the State of Montana, who will perform the remedy and restoration activities with EPA and NPS oversight. The Consent Decree and State/EPA Memorandum of Agreement found at the links below provide the details of how the project will be performed.
Site Specific Memorandum of Agreement, December 21, 2007 (PDF,29 pp, 126 kB)
CFR RipES3
CFR RipES4
CFR RipES Appendix A
CFR RipES Appendix B
CFR RipES Appendix C
CFR RipES Appendix D
The file is a VERY, VERY large PDF file: 423 MB! The first step to downloading the file is to go to this publicly accessible ftp folder: ftp://ftp.epa.gov/r8/milltown. This folder contains the Public Review Draft Feasibility Study Report, and its filename is ClarkFork.pdf. The best way to open this file is to right-click on the icon, select Copy to Folder, select a folder, and click OK. It may take at least 20 minutes even on the fastest connections to download the entire document.
The ftp://ftp.epa.gov/r8/milltown folder above also contains these LARGE PDF files:
Remedial Investigation Report, August 1998, Volume 1 (329 pp)
Remedial Investigation Report, August 1998, Volume 2: tables and figures (437 pp)
Remedial Investigation Report, August 1998, Volume 4 (533 pp)
Record of Decision - Table of Contents
- Declaration
- Decision Summary
- ROD Summary fact sheet
- Responsiveness Summary
- Acronyms and Abbreviations, References
- Appendices:
- A: ARARs Requirements and Waivers
- B: Clark Fork River OU Streambank Stabilization Design Consideration and Examples
- C: Clark Fork River OU BMPs and Riparian Management Plan Considerations
- D: Clark Fork River OU Weed Prevention and Management Planning Information and Weed Species Fact Sheets
- E: Grant-Kohrs Ranch National Historic Site
- F: Concurrence Letter from State of Montana
EPA released an Ecological Risk Assessment (ERA) in December 1999 followed by an ERA addendum in August 2001. The Feasibility Study was completed by EPA in March 2002. This report contains a detailed list of other related laws and regulatory requirements called applicable or relevant and appropriate requirements (ARARs).
| Summary Fact Sheet, 300K, PDF |
Community Involvement
EPA recognizes that community involvement is key to achieving a successful cleanup of the Clark Fork River. In the past, EPA has conducted community interviews and issued several fact sheets. EPA has also funded a technical assistance work group called the Clark Fork Technical Assistance Committee to provide the public with independent technical reviews of EPA and DEQ Clark Fork River activities, reports, and meetings.Public meetings have been held, and will continue to be held to provide the public with an opportunity for exchanging information with the agencies involved as the site progresses towards Remedial Action. EPA is planning meetings with individual landowners to discuss the RipES work. These meetings will also provide EPA and opportunity to hear landowners' concerns and learn about current land management practices, and discuss how future cleanup activities may impact those operations.
Map of Clark Fork River Basin
Contacts
U.S. EPARegion 8, Montana Office
Federal Building
10 West 15th Street,Suite 3200
Helena, MT 59626
(406) 457-5021
edwards.kristine@epa.gov