HomeMy WebLinkAbout05-24-22 Correspondence - EPA - Long Term Effectiveness rd
Long Term Effectiveness s-ay—rye
EPA completed the Fifth Five-Year Review in September 2020 and determined the remedy currently protects
human health and the environment due to institutional controls limiting activities that could negatively impact
cleanup actions at the Site. Current institutional controls include:
• A Controlled Groundwater Area prohibiting installation of new wells.
• Permanent enforceable land use controls minimize potential for human exposure to contaminated soil and to
protect the integrity of the soil and groundwater remedies. Land use restrictions apply to the entire IPC
property, although the restrictions vary depending on the location.
United States Environmental Protection Agency, Region 8—Montana Office
10 W. 15th St., Suite 3200
Helena, MT 59626 'sue r
Attn: Roger Hoogerheide
4 ;
Official Business
Address Service Requested V
OS
MAYOR CYNDY ANDRUS
121 N ROUSE AVE
BOZEMAN, MT 59715
Upcoming Activities
Public Comment Period
• EPA is proposing a prospective purchaser settlement agreement with Scout DAC LLC (the purchaser) and
requests comment on the proposed agreement. The comment period is open from May 13 through June 13.
• Learn more at www.epa.gov/superfund/idaho-pole
Groundwater
• Ongoing groundwater monitoring, including residential wells, will continue twice a year.
• EPA and IPC are negotiating an Administrative Order on Consent for injection of a substantial amount of in
situ amendments into the subsurface soils and groundwater followed by seven years of monitoring.
• IPC plans to inject amendments in the subsurface in Summer 2022 using a drill rig.
Background
Between 1945 and 1997, IPC operated a wood treating facility near the northern limits of Bozeman, resulting in soil
and groundwater contamination. In 1986, EPA listed the area on the National Priorities List as the "Idaho Pole
Company Superfund Site." In 1992, EPA and DEQ developed an initial cleanup plan establishing cleanup levels for
the contaminants of concern: PCP, PAHs, and dioxins. This 1992 Record of Decision also selected remedies to
address soil and groundwater contamination at the Site.
SPRING 2022 SITE UPDATE 2
IDAHO POLE
COMPANY
SUPERFUND SITE
MAY 2022 SITE UPDATE:. BOZEMAN,-MT.1.REGIOM O.
The prospective purchaser will place an impervious
10 cover(e.g. asphalt, concrete) on top of the
Consolidated TSA to enhance protectiveness. The
Redevelopment
■��■ cover will restrict surface water infiltration into the
EPA and the Montana Department of treated soils and reduce the potential for
Environmental Quality (DEQ) have negotiated a contaminants to leach to groundwater.
Prospective Purchaser Agreement with a developer
planning to purchase property at the Site south of 190 The prospective purchaser will also construct a
from Idaho Pole Company. Any future development stormwater system to collect runoff from the
of the Site needs to be done in a way that protects impervious cover and direct any stormwater away
human health and the environment. from the Consolidated TSA.
There is a 30-day public comment period on the Groundwater Remedy
proposed Prospective Purchaser Agreement. The
agreement will enhance the protectiveness of the soil Initially, from 1997 to 2016, IPC managed
remedy. groundwater contamination using a pump and treat
system before re-injecting treated water back into the
aquifer. Based on continued water quality improvement
Soil Remedy observed at downgradient wells in 2017, IPC
permanently decomissioned the system in 2018 with
From 1995 to 2002 the Idaho Pole Company (IPC), a EPA approval.
potentially responsible party for the Site, excavated EPA and DEQ are working with IPC to inject
and treated approx. 24,000 cubic yards of amendments into the barkfill area and three down
contaminated soils. IPC used treated soils as backfill gradient barriers this summer; this is known as in-situ
on 4.5 acres on the Site (referred to as the Treated treatment since it is occuring in place (in-situ). The
Soils Area or TSA), then covered the TSA with 12- on-Site treatment south of 190 will address the
inches of clean soil to prevent direct contact with residual wood treating fluids to prevent groundwater
underlying contamination. In 2020, the soil remedy contamination. Just north of 190, along Bohart Lane
was deemed protective and the soil section of the site and downgradient, three injection sites will treat
(except the Treated Soils Area)was removed from passing contaminants that have already left the
the Superfund National Priorities List. source area; thus, enhance cleanup of the
In 2021, the prospective purchaser collected surface downgradient portions of the plume. This work is
soil samples for dioxin, pentachlorophenol (PCP) and ongoing and separate from the planned soil work the
polycyclic aromatic hydrocarbons (PAHs) to support prospective purchaser will perform under the
proposed property development south of 190. Prospective Purchaser Agreement.
Sampling results were below cleanup levels
established in EPA's 1992 Record of Decision. For More Information, Contact
Additional subsurface soil sampling is ongoing. To
ensure that no treated soils remain in the newly Roger Hoogerheide, EPA Project Manager, 406-
delineated floodplain, the prospective purchaser has 422-9725, hoogerheide.roger@epa.gov
agreed to remove treated soils north of Cedar Street Gordon Levin, DEQ Project Officer, 406-444-6569,
(barkfill area) and consolidate them with other treated
soils south of Cedar Street (called the Consolidated gordon.levin@mt.gov
TSA). www.epa.gov/superfund/idaho-pole
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