Toastmaster Macon Superfund Site, Macon, Macon County, Missouri - Fact Sheet, August 2020
Public Comment Period and Administrative Record File Available
Engineering Evaluation/Cost Analysis for Non-Time-Critical Removal Action
The U.S. Environmental Protection Agency (EPA) Region 7 is soliciting public input on the Engineering Evaluation/Cost Analysis (EE/CA) for the Toastmaster Macon Superfund Site. An EE/CA looks at environmental conditions and ways to clean up contamination. (See below for how to comment).
The Toastmaster Macon Superfund Site (site) encompasses a light industrial and residential area of Macon, Missouri, where trichloroethylene (TCE) has been detected in the groundwater, soil gas, and indoor air at the former Toastmaster small-appliance manufacturing facility and other nearby properties. TCE is the main contaminant of concern at this site.
The facility, generally located at 704 South Missouri Street, is now occupied by Compton’s Furniture & More, a retail outlet. Compton's LLC is the current owner of the facility. EPA Region 7 reached settlements with Compton’s LLC, Spectrum Brands Inc., and Cooper Industries LLC, the current and previous owners of the facility, to address TCE contamination at the site.
An EE/CA is a study completed in advance of Superfund cleanups for non-time-critical removal actions. It identifies the goals for the cleanup and reviews the cost and feasibility of the cleanup options (also known as alternatives). EPA studied options for a removal action to address TCE contamination during a non-time-critical removal action. EPA, current and previous owners of the facility prepared the EE/CA to address contamination at the site. For this site, the EE/CA evaluated four alternatives, both individually and in combination.
- Thermal Treatment – direct source area thermal (heat) treatment to reduce contaminant concentrations and reduce migration from soil to groundwater.
- Soil Excavation – direct removal of all or a portion of source zone contaminated soils including ex-situ (conducted outside of its original location) treatment and/or disposal.
- In-Situ (in place) Stabilization – source area soil stabilization to prevent or reduce migration of contamination from soil to groundwater.
The EE/CA recommends the selection of Thermal Treatment in the form of In-Situ Thermal Remediation (ISTR). Specifically, this alternative includes the following:
- ISTR technologies include various methods for applying energy to the subsurface to raise in-situ (in place) temperatures within a targeted treatment area. Basically, this approach uses heat to reduce the level of contamination in the soil.
- ISTR is generally classified as an enhanced physical recovery technology for addressing volatile organic compounds (VOCs) and select semi-volatile organic compounds (SVOCs), as it is typically employed in combination with physical extraction methods (e.g., Multi-Phase Extraction [MPE], Soil Vapor Extraction [SVE], etc.) and ex-situ treatment of recovered vapors/fluids.
- The primary effect of introducing heat to the subsurface is expedited VOC mass transfer to the vapor phase by increasing vapor pressures/volatilization rates, increasing the air permeability of the soil, and enhancing the gas-phase diffusion process, thereby significantly improving vapor-phase mass removal rates.
EPA will prepare a Responsiveness Summary after the public comment period closes. The Responsiveness Summary will summarize all substantive comments submitted to EPA during the comment period and provide EPA's responses to them.
HOW TO COMMENT
Public comments on the Engineering Evaluation/Cost Analysis (EE/CA) will be accepted from Wednesday, Aug. 26, 2020, through Friday, Sept. 25, 2020. The EE/CA and the Administrative Record file (AR file) for this site are available online (see Administrative Records).
Written comments, questions about the EE/CA and AR file, or requests for information can be directed to:
Community Involvement Coordinator
U.S. EPA Region 7 (ORA/OPA)
11201 Renner Boulevard
Lenexa, KS 66219
Lenexa KS 66219
Upon timely request, the comment period can be extended by 15 days.
TCE INFORMATION AND HEALTH RISKS
TCE is used in industrial solvents and degreasers, and household products such as correction fluids, paints, paint removers, adhesives, rug and metal cleaners, and spot removers. It is a manufactured substance and does not occur naturally in the environment. TCE is the primary contaminant of concern at the site.
Exposure to TCE poses potential human health hazards to the central nervous system, kidney, liver, immune system, male reproductive system, and developing fetus. TCE is characterized by EPA as “carcinogenic in humans” by all routes of exposure.
From the mid-1950s to 2001, Toastmaster Inc., manufactured small appliances at the facility. In 1991, during Toastmaster’s ownership, TCE was discovered to have been released from an above-ground storage tank on the facility, and also found in nearby groundwater. Further investigation found that TCE vapors were present in both the indoor air and sub-slab air of the facility. In July 2014, the Missouri Department of Natural Resources conducted indoor air and sub-slab soil gas sampling in homes in the immediate vicinity of the facility to determine whether the contaminants from the facility were impacting nearby residences.
The results of this sampling documented elevated indoor air and/or sub-slab levels of TCE in two of the nearby residences. TCE had volatized (evaporated) and entered the indoor air through vapor intrusion. In October 2014, EPA conducted a Superfund removal action and installed sub-slab vapor mitigation devices in the two affected residences. Sampling was conducted at nearby residences in 2016 and 2017. The responsible parties, through the settlement that EPA reached with them, installed another sub-slab vapor mitigation device at a third residence.
EPA has visited the site many times to continue oversight, sampling of indoor and outdoor air, and other mitigation activities. EPA has reviewed data collected during these and the most recent sampling events. EPA has held public availability sessions/meetings and distributed site information in various ways.
FOR ADDITIONAL SITE INFORMATION
A Public Notice related to this Fact Sheet is available online.
Additional site information including the Community Involvement Plan are also available online.