Background
The Page & Hill Forest Products, Inc., site in Big Falls, Minnesota was added to the Minnesota Permanent List of Priorities in 2010.
The Page & Hill Forest Products, Inc. site is located on approximately 17 acres southeast of the intersection of U.S. Highway 71 and County Road 31 in Big Falls, Koochiching County, Minnesota. Wood treatment operations occurred at the site from 1947 - 2006 and included using a mixture of diesel fuel and pentachlorophenol (PCP). Untreated wood was placed in above ground vats and submerged in the diesel/PCP mixture. After treatment, the wood products were stored outdoors at the site, or directly loaded onto rail cars. The PCP treatment process was eventually replaced with a process that used ammonia, zinc, copper and arsenate, until operations ceased at the site in 2014.
The site geology consists of surficial deposits composed of sands and silty sands of varying thicknesses overlying clay. The sand and clay deposits are attributed to Glacial Lake Agassiz and extend 50 feet deep to the Precambrian metamorphosed sedimentary rock. Groundwater has been encountered from two to seven feet below ground surface across the site.
Property at the site was leased from Burlington Northern Railroad in the mid 1940’s until 1992, and from the Minnesota Department of Transportation (MnDOT) from 1992 to 2014. Between 1974 and 1992, the Minnesota Pollution Control Agency (MPCA) documented several leaks and spills of the diesel/PCP mixture at the site. In addition, a local newspaper reported that a large explosion at the facility in 1958 destroyed three 10,000 gallon above ground storage tanks, two diesel tanks and one PCP tank. As a result, an unspecified amount of product released to the ground surface at the site.
Meanwhile, numerous environmental investigations have been completed at the site beginning in 1994 as a result of a Stipulation Agreement between the MPCA and Page & Hill. In an agreement with the MPCA, Page & Hill enrolled in the MDA’s Agricultural Voluntary Investigation and Cleanup Program in September 1995 to complete investigation and cleanup as required under terms of the Stipulation Agreement. Under the oversight of the MDA, approximately 700 cubic yards of contaminated soil was excavated from below one of the treatment vats in 2003 and placed in a Land Treatment Corrective Action Management Unit (LTU) previously constructed on-site. PCP levels in soils in the LTU decreased from a range of 47 -250 milligrams per kilogram (mg/kg) in 2003 to 2 – 11 mg/kg in 2006. The excavated soil remains in the LTU.
Ground & Surface Water Contamination
Groundwater monitoring at the site and adjacent properties was consistently conducted from 1996 -2016. That testing showed that the groundwater flow direction is typically to the east-southeast. PCP contamination levels in groundwater are highest near the former wood treatment areas on the site, ranging from 14,000 to 120,000 parts per billion (ppb). PCP contamination in groundwater on property adjacent to the east has averaged 42,000 ppb over 29 sampling events since 1996. During the same sampling period, PCP contamination was routinely detected in surface water samples in drainage ditches on either side of the abandoned rail bed located adjacent to the Site. The ditches drain to the Big Fork River located approximately 550 feet south of the Site. Ground and Surface water monitoring has been limited since 2007.
Site security measures including installation of a perimeter fence and placement of a soil cover on a portion of the Blue Ox Trail detour were completed in September 2020.
The MDA issued a Revised Request for Response Action in November 2020 to the Responsible Parties to investigate and remediate the remaining contaminated soil and groundwater at the site. An updated Remedial Investigation Work Plan was approved in April 2021 to evaluate horizontal and vertical extent of DRO, PCP and dioxin impacts in soils at the Site.
For more information please contact the MDA staff listed above.
