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Congressional District # 08


EPA ID# MND057597940
Last Updated: January, 2014

Site Description

The St. Regis Paper Company (St. Regis) Superfund site occupies 125 acres within the exterior boundaries of the Leech Lake Band of Ojibwe (LLBO) Indian Reservation in the city of Cass Lake in Cass County, Minnesota.  The St. Regis site is located north of the Chippewa National Forest and west of Pike Bay and Cass Lake.

The St. Regis Paper Company began wood treatment activities at the site in the 1950s while leasing the land from the Great Northern Railroad (now the Burlington Northern Santa Fe (BNSF) Railway Company).  Lumber was pressure-treated with creosote, pentachlorophenol (PCP), and copper chromium arsenate.  Wastewater from these processes was discharged into a number of disposal ponds located at the site.  Between 1957 and 1960, wastewater and sludges were hauled to a pit within the former Cass Lake city dump and burned.  The disposal from the ponds occurred almost daily at an estimated rate of 500 gallons per day for a total of 547,500 gallons over the three-year period.  From 1960 to 1975, unknown quantities of sludge were hauled to the city dump pit. The pit, containing the ash and unburned residuals, was eventually covered.

EPA placed the St. Regis site on the Superfund National Priorities List in 1984.  In 1985, Champion International Corporation (Champion) acquired the property through a merger with the St. Regis Paper Company and closed site operations.  A large portion of the former operations area was then deeded to the city of Cass Lake.  Other portions of the site are located on BNSF and Cass Forest Products properties.   Champion International Corporation was acquired by International Paper (IP) in 2000 and IP is the current owner of the former Champion portion of the St. Regis site.

Site Responsibility

The St. Regis site is being addressed through potentially responsible parties' (PRPs) actions under state and federal oversight.  EPA conducts oversight of PRP work along with our support agency partners, the Leech Lake Band of Ojibwe (LLBO) and the Minnesota Pollution Control Agency.

Threats and Contaminants

Groundwater, soil, and sediment on and in the vicinity of the St. Regis site have been contaminated with polycyclic aromatic hydrocarbons (PAHs), heavy metals, and pentachlorophenol (PCP).  Dioxins and furans, impurities in PCP, are also chemicals of concern. 

Cleanup Progress

In 1986, the Minnesota Pollution Control Agency (MPCA) signed two Minnesota Enforcement Decision documents that outlined its selected response actions for each cleanup area at the site. These areas include the treatment facility, the Cass Lake City Dump Pit, a contaminated soil vault, and the extension of the Cass Lake municipal water system. In 1987, then owner Champion constructed groundwater extraction wells at both the treatment facility area and the city dump area. The contaminated groundwater is extracted, treated on site and then discharged into a channel between Pike Bay and Cass Lake.  An on-site containment vault was constructed that contains 37,500 cubic yards (yd3) of contaminated soil and sludge from the wastewater lagoons and 4,500 yd3 of contaminated soil and sludge from the city dump pit. Current owner International Paper (IP) has monitored and maintained the treatment system and soil vault since 2000.

As a result of Five-Year Reviews (FYR) that EPA conducted at the site in 1995 and 2000, field sampling work was conducted by EPA in October 2001 to collect data to evaluate whether the initial response actions remained protective of human health and the environment.  Sample results showed that dioxin was present at levels above Superfund Removal Action Levels in shallow soils on the site property.  Additional confirmatory and delineation sampling was then conducted by International Paper (IP) under an order from EPA in August 2003.  Removal actions for shallow soil above 1 ppb TEQ Dioxin were conducted during 2004, 2005, and 2006 by IP and BNSF Railway Co. under orders from EPA.

EPA also ordered IP to conduct a Human Health and Ecological Risk Assessment at the site.  In 2004, IP sampled area soil, house dust, sediment, surface water, plants, invertebrates, and fish in support of the human health and ecological risk assessments.  In 2005, after analysis of the data from the sampling, EPA decided that an interim cleanup approach was needed for dioxin and arsenic contamination in residential settled dust that was above screening levels.  The interim cleanup actions included an initial comprehensive cleaning of site area residences that included carpet replacement, HEPA vacuum cleaning, wet wiping, steam cleaning of soft furniture, and cleaning of draperies and rugs. In addition, supplemental periodic cleaning of homes, clean soil yard cover, and dust suppression to the unpaved roads was required. In 2006, under an order from EPA, IP conducted all initial cleanings, the yard work, dust suppression, and continues the periodic house cleanings.  Periodic cleanings continue to date.

A 2005 FYR of the site also concluded that additional information was needed to determine whether the groundwater remedial actions were protective of human health and the environment.  IP drilled new soil borings and monitoring wells in 2006, 2007-2008, and 2009 and defined the extent of a tarry liquid in the City Dump plume. IP also conducted a site-wide pumping test and an investigation near ground water wells owned and operated by the LLBO to determine the effectiveness of the till aquitard between the contaminated upper aquifer and the lower aquifer from which the Band takes drinking water.

In 2008, EPA approved the human health portion of the risk assessment and concluded that there are unacceptable risks to human health and the environment from contaminated soil at the site.  An Administrative Order on Consent for a Feasibility Study to develop remedial alternatives for soil clean up at the site was signed by EPA and the PRPs in September 2008.  EPA approved the Feasibility Study Report in April 2011 and announced a preferred remedy for contaminated soil in a Proposed Plan in June 2011. EPA’s agency partners and many residents of the Cass Lake area opposed the preferred remedy, and the agency partners asked EPA to require additional soil sampling before issuing a Record of Decision (ROD) to select a final soil remedy.  EPA complied and formed a soil technical workgroup in 2012 to plan the collection of additional soil data and then IP conducted the sampling in fall 2013.  EPA is now working with its agency partners and the PRPs to revise the Feasibility Study by summer 2014 so that EPA may either issue a new proposed cleanup plan for public comment or a ROD to select a soil remedy in late 2014.

The 2010 FYR Report found that hydraulic capture was incomplete in the former operations area and possibly also in the City Dump burn pit area. IP collected groundwater and soil samples in summer 2012 on the eastern edge of OU1 to evaluate contaminant plume capture in this area, and in winter 2012-2013 to define the extent of the dissolved contaminant plume at the City Dump burn pit. IP is also generating a new ground water model under the oversight of the EPA and its partners to evaluate the overall effectiveness of the groundwater extraction and treatment system.

The 2012-2013 supplemental soil investigation (see above) also found high levels of site contaminants and visually contaminated soil down to the water table in the southwestern area of OU2 where waste was historically dumped. The PRPs will collect soil and groundwater samples in winter 2013-2014 to assess any groundwater impacts in this area.

EPA plans to conduct the next FYR of the St. Regis site in 2015.

Success Story

During the past 9 years, the level of effort on this site has been very high from EPA, state and Tribal regulators, the local community, and the potentially responsible parties.  Removal actions and interim remedial actions have been taken to reduce health risks to the local residents while EPA works to select a final cleanup remedy. 

Community Involvement

EPA held a public meeting in July 2012 regarding the additional sampling that will be done before a final soil cleanup action is selected. EPA sent the first issue of a bi-annual newsletter in March 2013.

Congressional Interest

Congressman James Oberstar and Senator Klobuchar have maintained an interest in the St. Regis site. State Representative John Persell is the Superfund Coordinator for the Leech Lake Band of Ojibwe. Staff from Senator Al Franken’s office requested information on the Human Health and Ecological Risk Assessment in November 2012, and requested additional information in August 2013.

Property Reuse

The city of Cass Lake zoned the former operations area and much of the adjacent properties as commercial/industrial in January 2006. The surrounding residential properties are zoned residential. In 2012, Cass Lake announced a draft plan to redevelop the city-owned property on the site. In December 2013, the PRPs informed EPA of a tentative plan to prepare 5 acres of the site for a propane distribution facility.


Remedial Project Manager, U.S. EPA
leslie patterson (patterson.leslie@epa.gov)
(312) 886-4904

Community Involvement Coordinator, U.S. EPA
heriberto leon
(312) 886-6163




Site Profile Information

This profile provides you with information on EPA's cleanup progress at this Superfund site.


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