Region 8

Smurfit-Stone Mill

Smurfit-Stone Mill site location map

Site Type: Proposed NPL
Street Address: 14377 Pulp Mill Road
City: Missoula
County: Missoula
ZIP Code: 59808
EPA ID: MTN000802850
SSID: A804
Site Aliases: Frenchtown Mill
Congressional District: At large

What's New?

Updated January 2014

With support from Missoula County, Missoula City-County Health Department and the Montana Department of Environmental Quality (MDEQ), and the Tribal Council of the Confederated Salish and Kootenai Tribes, EPA announced a proposal to add the Smurfit-Stone Mill site near Frenchtown, Montana to the National Priorities List (NPL), making it eligible for comprehensive assessment and cleanup resources under EPA’s Superfund program.

The Superfund law guarantees the public an opportunity to participate throughout the Superfund process.

The Smurfit-Stone Mill site is located on the eastern bank of the Clark Fork River approximately four miles south of Frenchtown and twelve miles northwest of Missoula. The preliminary investigation focused on the sludge ponds and wastewater storage ponds at the site as well as their impact on local groundwater and the Clark Fork River.

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Site Description

The Smurfit-Stone Mill was a large integrated pulp and paper mill that operated from late 1957 through early 2010. The former mill is located 11 miles northwest of the city of Missoula, in Missoula County, Montana, and covers approximately 3,200 acres. The mill is located approximately three miles south of the town of Frenchtown and, therefore, has often been referred to as the Frenchtown Mill.

The core industrial footprint of the mill site covers approximately 100 acres. Over 900 acres of the site consist of a series of unlined ponds used to store both treated and untreated wastewater effluent from the mill, as well as primary sludge recovered from untreated wastewater. Some ponds initially used to store wastewater were subsequently drained and used for the land-filling of various solid wastes produced at the mill. The site includes landfills used to dispose of solid wastes including general mill refuse, boiler fly ash, lime kiln grits, ragger wire and asbestos.

The site began operation as a pulp mill in the fall of 1957. Later expansions and improvements allowed the facility to produce paper, primarily rolls of kraft linerboard that is used in the production of corrugated containers (i.e., the outside layers of cardboard boxes). Linerboard produced at the mill was shipped to box plants, where it was used to make a variety of corrugated containers. The mill ceased operations in January 2010.

Various hazardous chemicals were used or produced on-site, including bleaching chemicals. The use of chlorine for the bleaching of pulp produces chlorinated organic compounds, including dioxins and furans, through the reaction of chlorine with residual lignin.

Potential sources of metals at pulp and paper mills include chemical additives to the pulping process, biocides that contain mercury, and dyes such as cadmium salts. Fly ash from boilers may concentrate naturally occurring metals found in soils.

Source areas on the site confirmed through chemical analysis include four sludge ponds, an emergency spill pond, an exposed soil pile adjacent to landfill A, one wastewater storage pond and a soil land farming area. These were the only areas sampled, as they were determined to have the highest potential for containing hazardous substances, or, in the case of the wastewater storage pond, were determined to be the most at risk in the event of a catastrophic flood. Additional potential sources at the site that have not been sampled include 11 additional wastewater storage ponds, three wastewater treatment aeration basins, two polishing ponds, the industrial core and log loading facilities.

The assessment revealed elevated levels of dioxins, furans and metals, including manganese, arsenic, lead, barium and cadmium in a series of soil samples collected from sludge ponds and wastewater holding ponds. Semi-volatile organic contaminants including methylphenol, phenanthrene and di-n-butyl phthalate were detected in soil samples as well.

Analytical results indicate dioxins and furans have migrated to the sediment of the Clark Fork River. Shallow groundwater sampled at the site had elevated concentrations of dioxin and furan congeners, and metals including manganese and arsenic.

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Potential Site Risk

Media Affected Contaminants Source of Contamination
surface soils (former sludge, wastewater and emergency spill ponds) dioxins, furans, various metals including arsenic, cadmium, lead and manganese; semi-volatile organic compounds such as methylphenol, di-n-butyl phthalate, phenanthrene and naphthalene direct contact with primary sludge, wastewater
surface water dissolved manganese primary sludge and wastewater ponds
river sediments dioxin, furans primary sludge and wastewater ponds
groundwater dioxins, furans, various metals including manganese, arsenic, chromium and lead leaching from primary sludge and waste water ponds

The data confirm that contaminants including dioxins, furans, arsenic and manganese are present in the surface and subsurface soils at the site. These contaminants have also migrated to groundwater and the sediments of the Clark Fork River.

Dioxins and furans are the short names for a family of toxic substances that all share a similar chemical structure and health effects. Studies have shown that exposure to dioxins at high enough levels may cause a number of adverse health effects, including cancer.

EPA considers 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8 TCDD), 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (1,2,3,4,6,7,8-HpCDD), 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (1,2,3,6,7,8-HxCDD) and 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) to be hazardous substances. All four have been detected in sediments of the Clark Fork River, in the groundwater beneath the site, and in surface soils within the Smurfit-Stone Mill site. While a formal risk assessment has not been conducted, potential risks include ecological impacts, human food chain exposures and further contaminant migration.

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Investigation Results

An Analytical Results Report for a Combined Site Inspection and Removal Assessment was completed for the Smurfit-Stone Mill site in August 2012. Results from that report are summarized here. The full report for this investigation, as well as other investigations, is available in Site Documents below.

Soil Exposure Pathway – Soil samples were collected from sludge ponds, wastewater holding ponds and an emergency spill pond at the site. Samples were not collected from landfills at the site. Multiple congeners of dioxin were detected at levels greater than background concentrations. Metals and other inorganics, such as arsenic and manganese, were detected above background concentrations in two sludge ponds. Sludge ponds 3 and 17, and emergency spill pond 8, had the highest concentrations of contaminants of the locations sampled on the site. It should be noted that only a subset of ponds at the site were sampled.

Groundwater Migration Pathway – Shallow groundwater at the site had detections of multiple dioxin congeners and manganese. Arsenic was also present in the shallow groundwater at levels exceeding federal drinking water standards. Nearby down-gradient and cross-gradient domestic wells draw water from a deeper aquifer, and the wells that were sampled did not show any indication that they are currently impacted by the site.

Surface Water Migration Pathway – Sediments from the Clark Fork River had detections of multiple dioxin and furan compounds at higher than background concentrations. Additionally, dissolved manganese in the surface water was detected at higher than background concentrations. This stretch of the Clark Fork River is used by anglers. Fish tissue samples were not collected as part of the site assessment. With the limited amount of data captured as part of this sampling event, it is unknown if bioaccumulation of these contaminants is a concern.

Air Migration Pathway – Air samples were not collected as part of this sampling event. It has been reported to MDEQ and Missoula County Health Department that fugitive dust emissions have occurred since operation at the site has ceased and the ponds have dried up. These dusts may contain similar compounds as those detected in other surface soil samples from the site.

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Next Steps

After the comment period comes to a close, EPA will review the comments. We will respond to those needing a response and complete a responsiveness summary of all comments. If the recommendation is to list the site on the NPL, the action will be finalized in a Federal Register notice. The earliest the Smurfit-Stone Mill site could be finalized on the NPL would be in the spring of 2014.

The Remedial Investigation/Feasibility Study (RI/FS) is the first phase of the Superfund process. Work typically begins once a site is finalized on the NPL. The RI/FS phase of the process determines the nature and extent of contamination at the site, tests whether certain technologies are capable of treating the contamination, and evaluates the cost and performance of technologies that could be used to clean up the site. Community involvement during the RI/FS is highly encouraged. For information on how to get involved, visit Superfund Community Involvement.

Site Documents

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.

Federal Register notice of National Priorities List, Proposed Rule No. 59 (PDF), December 12, 2013(9 pp, 254 K)

Federal Register notice of National Priorities List, Proposed Rule No. 58 (PDF), May 24, 2013(8 pp, 226 K)

Letters supporting NPL proposal from Montana Governor Schweitzer, the Confederated Salish and Kootenai Tribes Tribal Council, Missoula County Commissioners, Missoula County Board of Health and the Missoula County Water Quality Advisory Council, November–December 2012

Public Presentation: Overview of EPA Activities, November 8, 2012 

Results Fact Sheet, November 8, 2012 

Analytical Results Report for a Combined Site Inspection and Removal Assessment, August 30, 2012

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Frequently Asked Questions

1. How did the EPA learn about the site?

After the Smurfit-Stone Mill closed and sat vacant for most of a year, the Montana Department of Environmental Quality (MDEQ) requested that EPA conduct a preliminary assessment and site inspection (PA/SI) to determine environmental impacts from the former operation.

2. What is the EPA doing?

EPA completed a preliminary assessment and site inspection in September 2011 and August 2012, respectively, at the request of Missoula County and Montana Department of Environmental Quality. A site inspection includes environmental sampling to determine what wastes are present at the site and if the waste is migrating off-site. EPA collected samples from the surface soils and subsurface soils at the site, as well as from the groundwater, nearby domestic wells and surface water and sediment samples from the Clark Fork River, which flows by the western edge of the site. The analytical data from these samples has been included in EPA’s Analytical Results Report, which can be found in Site Documents below.

EPA has proposed that the site be added to the Superfund National Priorities List (NPL), making it eligible for additional study and cleanup resources under EPA's Superfund program.

3. What are the benefits of the NPL?

NPL placement ensures that a comprehensive investigation will occur, that any identified human and environmental risks will be addressed and, if necessary, that the problem will be cleaned up. The NPL provides access to technical and financial resources that are otherwise unavailable. In addition to funds for investigation and cleanup, NPL listing unlocks resources for communities to help them better understand the technical issues and guarantees that citizens and other stakeholders will have the opportunity to provide input in the process and comment on decisions before they are made. Community involvement is ongoing throughout the investigation and cleanup.

4. What contaminants have been found at the site?

The data we have collected indicate multiple contaminants present above background conditions in the surface and subsurface soils at the site. Various dioxin and furan compounds, common byproducts of bleaching operations, were detected in the sludge ponds soils, emergency spill pond soils and the wastewater storage pond soils. Arsenic, manganese, phenanthrene, di-n-butyl phthalate, cadmium, lead, zinc and 4-methylphenol were detected in the emergency spill pond or a sludge pond. Based on the sampling results, EPA does not believe there is an imminent human health danger posed by the site. The ponds with the highest concentrations of contamination are sludge ponds 3 and 17, and emergency spill pond 8. The primary treatment clarifier sludge was disposed of in the sludge ponds, so it makes sense that these areas have the highest concentrations of contamination of all the sample locations on the site. Soils in landfills at the site were not sampled, but groundwater was sampled at sites believed to be down-gradient of the landfills.

5. Have any contaminants migrated from the site to the groundwater or Clark Fork River?

Yes. Multiple dioxin and furan compounds have been detected in groundwater and in sediments in the Clark Fork River. Arsenic, chromium, manganese and zinc were detected in the shallow groundwater beneath the site. Nearby domestic wells did not appear to be impacted. Manganese was detected in the stretch of the Clark Fork River that is on the western edge of the site. EPA does not believe there is an imminent human health danger posed by the site.

6. Does an emergency situation exist?

No. While documented releases to the groundwater and Clark Fork River exist, sampling data does not indicate that an emergency situation currently exists.

7. Is drinking water in the area safe?

At this time EPA is not aware of any people who are drinking contaminated water. Nearby drinking water wells were sampled and did not show any evidence of impact from the site. Missoula’s water supply comes from upstream sources and Frenchtown’s water supply is a groundwater source further down-gradient than the sampled domestic wells.

8. Are the fish and crayfish in the area and down river safe to eat?

No fish or crayfish studies were conducted during EPA's site assessment. A thorough risk assessment, including the evaluation of human food chain concerns, would be conducted as part of a Remedial Investigation and Feasibility Study if the site were proposed to the National Priorities List (also known as Superfund).

9. I’ve seen dust blowing off of the site. Have air samples been collected?

No air samples have been collected as part of the site assessment to determine the contaminants present in the dust. It is possible that the soil migrating off of the site might contain similar contaminants as the surface soils detected elsewhere on the site. This pathway of concern would be investigated as part of the remedial investigation/feasibility study.

10. What would happen if the site flooded?

While flooding is a possibility and concern, we have yet to fully characterize the site and thus cannot speculate what would happen in the event of a flood. Flooding hazards would be evaluated as part of a remedial investigation/feasibility study if the site were proposed to the National Priorities List.

11. Is this a Superfund Site?

This site has been proposed by EPA to be included on the Superfund National Priorities List (NPL). If the site is finalized to the NPL, this will ensure that the site is fully characterized and any necessary cleanup occurs in a timely manner.

12. Does the site qualify for the National Priorities List (also known as Superfund)?

Yes. Based on documented impacts to the Clark Fork River and shallow groundwater, the site does qualify for the NPL.

13. When can the site be finalized to the NPL?

Sites are finalized to the NPL via a formal rulemaking process that typically takes place twice each year, in the spring and fall. The spring of 2014 would be the soonest the site could be finalized to the NPL.

14. Can the EPA oversee and ensure that cleanup occurs outside of the NPL process?


15. Who decides how an NPL site is cleaned up?

The federal government and states have the authority under the Superfund law to make the final cleanup decisions. However, the Superfund law also requires that the community be given every opportunity to have meaningful input on how the cleanup is completed. EPA is committed to involving any interested citizens or groups along with state and local government throughout the decision process.

16. How soon could cleanup start?

If the site is finalized to the NPL, a Remedial Investigation and Feasibility Study (RI/FS) is the next step in the process. This investigation will more fully characterize site conditions, determine the nature of the waste, and assess risk to human health and the environment. These are important factors that help inform the decision of appropriate cleanup options.

17. How long will it take to clean up under Superfund?

The length of the cleanup will be dependent on many factors, including the types of contaminants found and the extent of contamination. These factors have not been fully defined. The next step would be to conduct a Remedial Investigation to further define these unknowns.

18. How much will cleanup cost?

At this point we have no way of knowing, as we only have limited site data. Full site characterization is necessary prior to considering cleanup options and associated costs. If the site is finalized to the National Priorities List (NPL), the next step is to conduct a Remedial Investigation and Feasibility Study (RI/FS), to determine the nature and extent of the waste and appropriate cleanup option. These are all unknown factors that will impact how much the cleanup will cost.

19. Who will be responsible for paying for any work at this site?

EPA adheres to the polluter-pays principal. We look for potentially responsible parties (PRPs) to assist or pay for the investigation and cleanup of the environmental problems they have caused. If no PRPs are identified, EPA does have the authority to conduct the cleanup itself.

20. Can private investment and redevelopment occur if the site is placed on the NPL?

Yes. In fact, the EPA Superfund Redevelopment Initiative was developed for just this purpose and has been highly successful. Available tools and resources, as well as several case studies, can be viewed on our Superfund Redevelopment page.

21. Will NPL listing impact redevelopment options?

No. Nothing would preclude redevelopment operations from continuing to take place at the site. Listing a site on the NPL is a process that will ensure environmental contamination is taken care of. Removing the environmental concerns at the site is a positive step towards redevelopment.

22. Can someone buy contaminated property without becoming CERCLA/Superfund liable?

Yes. Beginning in 2002, a bona fide prospective purchaser (BFPP) may buy property with knowledge of contamination and maintain their protection from liability provided they conduct "All Appropriate Inquires" (AAI), comply with continuing obligations and can demonstrate no affiliation with a liable party. More information is available on our Bona Fide Prospective Purchasers page.

23. What does "All Appropriate Inquires" mean?

"All Appropriate Inquiries," or AAI, is the process of conducting due diligence or a Phase I Environmental Site Assessment to determine prior uses and ownership of a property and assess conditions at the property that may be indicative of releases or threatened releases of hazardous substances. For liability purposes, a purchaser must conduct AAI prior to acquisition. More information is available on our All Appropriate Inquiries page.

24. What are continuing obligations?

In order to maintain their protection from liability, a new owner of a contaminated property must comply with the following continuing obligations: 1) comply with any land use restrictions and institutional controls; 2) take reasonable steps with respect to hazardous substance releases; 3) provide full cooperation, assistance and access to persons that are authorized to conduct response actions or natural resource restoration; 4) comply with information requests and administrative subpoenas; and 5) provide legally required notices.

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Robert Parker
Site Assessment Manager
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (EPR-B)
Denver, CO 80202-1129
800-227-8917 ext. 312-6664 (toll free Region 8 only)

Jennifer Chergo
Community Involvement Coordinator
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (OC)
Denver, CO 80202-1129
800-227-8917 ext. 312-6601 (toll free Region 8 only)

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