Congressional District # 07
NORTH BRONSON INDUSTRIAL AREAEPA ID# MID005480900
Last Updated: January, 2014
The North Bronson Industrial Area (NBIA) site, located in Branch County, Bronson, Michigan, consists of two lagoon areas and a county drain which runs adjacent to the lagoons. Several industries in the area discharged plating and other industrial wastes to seepage lagoons between 1939 and 1981. An industrial sewer system was used to transport plating wastes to lagoons located at the northeast and northwest ends of the site, which were owned and maintained by the City of Bronson. The seepage lagoons are no longer used for waste disposal; however, they contain an estimated 130,000 cubic yards of heavy metal sludges.
The majority of the City of Bronson is within a one-mile radius of the old lagoons at the NBIA site. The area surrounding the site is mixed industrial and residential; north of the site is primarily rural. Residents in the area of the site are connected to the municipal water supply system, although an estimated 3,000 people living within three miles of the site use wells as a source of drinking water. The primary supply wells are located approximately 5,000 feet west of the site and are screened in the upper aquifer.
The U.S. Environmental Protection Agency (EPA) proposed the NBIA site for the National Priorities List (NPL) in October 1984 and finalized the site on the NPL in June 1986.
Site ResponsibilityThis site is being addressed through federal, state and potentially responsible parties' (PRPs') actions.
Threats and ContaminantsHigh levels of trichloroethylene, dichloroethylene, and vinyl chloride (also known as volatile organic compounds or VOCs) as well as elevated levels of heavy metals and cyanide have been detected in private and groundwater monitoring wells in the area. Polychlorinated biphenyls (PCBs) and metals such as cadmium have been found in sediment samples downstream of the old lagoons. Lagoon sludge contains heavy metals, including cadmium, chromium, and lead. Municipal wells are located upgradient of the site with only a remote chance of site contaminants reaching these wells. Accidental ingestion of or direct contact with the contaminated groundwater, sediment, and sludge could pose a health threat to people.
In 1988, action was taken to eliminate immediate threats by removing from service private wells found to be contaminated with metals and VOCs. Alternate water supplies were provided to the affected residences. In 1993 and 1994, EPA Technical Assessment Teams were dispatched to the site. During the 1993 visit, the site was evaluated for immediate threats to human health. In several of the remaining buildings, waste piles, vats and drums were identified, characterized and secured. In 1994, the vats were pumped clean, and the drums were overpacked and removed from the site. The vats were covered and the buildings were secured to prevent trespassing.
The Remedial Investigation and Feasibility Study (RI/FS) was conducted by the State of Michigan with federal funding. Cleanup options to address the lagoons and the drain (Operable Unit 1 (OU1)) were evaluated and a decision on the final cleanup remedy was made in a June 1998 Record of Decision (ROD) signed by the Michigan Department of Environmental Quality (MDEQ) and EPA. The selected remedy for OU1 is to consolidate contaminated soils into one area of the western lagoons, dredge sediments from the County Drain #30 (CD30) and consolidate them in that area as well, and to construct a wetland to treat groundwater from the lagoon area.
Remedial Design and Remedial Action (RD/RA) negotiations with the potentially responsible parties began a week after the ROD was signed. A Consent Decree (CD) was signed by EPA and the five PRPs. The RD began in February 2000, with the first task being Pre-Design Studies (PDS). Field Work for the PDS took place between February 2001 and March 2001, including the installation of new monitoring wells, abandonment of wells, sampling sediment, and development of new wells.
The Draft PDS Report was submitted in July 2001 for EPA and MDEQ review and comment. The revised report was submitted on November 5, 2001, and did not meet the requirements of the Statement of Work and CD. Per a request from EPA, the Draft Phase II PDS Work Plan was submitted on May 20, 2002, which included additional field studies north and south of the County Drain #30. The final Phase II PDS Work Plan was submitted in July 2002.
Pre-Design Studies field work took place in August 2002. EPA received the Draft Phase II PDS Technical Memorandum in December 2002. Work conducted as part of the PDS showed possible problems with the implementation of the constructed wetland approach for groundwater treatment. Pending resolution of implementation issues with the ROD-selected groundwater treatment approach, the PRPs proposed to enhance the source control portion of the lagoon closure remedy by adding solidification and stabilization additives. This would give the lagoon sludges the strength necessary to support a cover and should reduce leaching of contaminants to groundwater. In 2006, the PRPs evaluated solidification and stabilization mixes and conducted a pilot scale field test of mixtures. EPA issued an Explanation of Significant Differences (ESD) document in September 2008 that clarified the cleanup requirements and documented that the use of stabilization and solidification is acceptable in conjunction with lagoon closure activities.
After lengthy discussions regarding design-related technical issues, the PRPs submitted an RD Work Plan for Operable Unit 1 on April 1, 2013, for review by EPA and MDEQ. A revised RD Work Plan that addresses agency comments is due in January 2014.
Modification to the original groundwater remedy selected in the ROD, if required, will be addressed though a future ROD amendment.
Operable Unit 2 (OU2) consists of groundwater and the Industrial Sewer used to transport liquid wastes to the lagoons. MDEQ began investigations of the sewer in September 1996, and the sewer was sampled again in May 1998. The results of these two sampling activities are contained in Technical Memorandums. During negotiations with the PRPs in 2000 for the FS, EPA and the PRPs agreed to evaluate upstream source area "abandoned facilities" prior to completing work on the Industrial Sewer.
North Bronson Former Facilities - The upstream sources that were identified as part of the discussions for OU2 were evaluated by EPA and the PRPs. These facilities collectively are known as the "North Bronson Former Facilities" and include the former Bronson Reel, the former L.A. Darling, and the former Scott Fetzer facilities. The status of each of these facilities is described below:
* Former Bronson Reel Facility -- EPA issued a Record of Decision for the former Bronson Reel facility on September 26, 2006. The ROD requires: (1) implementation of a warranty deed restriction on the property requiring follow-up sampling under the site buildings if the foundations are ever removed, and (2) the implementation of groundwater use restrictions because of concerns about possible groundwater contamination. No other risks from this source area were identified.
* Former L.A. Darling Facility -- The former L.A. Darling facility contains metal and solvent contamination in soil and groundwater. The PRP completed the RI Report in 2006 and submitted a draft FS for EPA review in late 2006. In late 2007, L.A. Darling commenced a partial removal of contaminated soil from the property to allow for the construction of a road though part of the property. In a Record of Decision issued in September 2008, EPA selected a cleanup approach for the facility. The ROD requires excavation of contaminated soils above the water table and institutional controls to allow commercial/industrial use of the property. The ROD selected an interim action for groundwater, with the selection of Air Sparging and Soil Vapor Extraction (SVE) to remove volatile organic contaminants. The ROD stated that if/when EPA determines that the efficiency of the Air Sparge / SVE system has diminished and is no longer removing sufficient levels of VOCs from the groundwater and saturated soils, the system will be converted to a groundwater extraction and treatment system. This approach, with Air Sparge/SVE and then “pump and treat” (if necessary), should dramatically reduce VOC concentrations at the facility. This groundwater approach is an interim remedy because it is not meant to address the entire contaminant plume from the former L.A. Darling facility. Groundwater contamination from the L.A. Darling facility may overlap with contamination from other sources. A cleanup plan to address combined plume areas will be issued as a separate decision document in the future. EPA issued a unilateral administrative order to the PRP in June 2011, requiring the PRP to design and implement the selected remedy. The Phase 1 portion of this cleanup (i.e., soil excavation and installation of the air sparging/soil vapor extraction system) was completed in June 2013 and has been operating since then. This system is expected to be effective in removing contaminants for approximately 2 years. If needed, Phase 2 of the selected remedly would then be used to address remaining groundwater contamination.
* Former Scott Fetzer Facility -- The former Scott Fetzer facility contains metal and solvent contamination in soil and groundwater. The site PRP completed the RI report in February 2008 and submitted the final FS report in June 2009. In a Record of Decision issued in September 2009, EPA selected a cleanup approach for the facility similar to the L.A. Darling cleanup plan (see above). The ROD requires partial excavation of contaminated soils above the water table, soil vapor extraction of volatile chemicals in soils, and institutional controls to ensure continued commercial/industrial use of the property. Like the selected remedy for the L.A. Darling facility, the ROD for the former Fetzer facility stated that if/when EPA determines that the efficiency of the Air Sparge/SVE system has diminished and is no longer removing sufficient levels of VOCs from the groundwater and saturated soils, the system will be converted to a groundwater extraction and treatment system. This groundwater approach is an interim remedy because it will not necessarily address the entire contaminant plume from the former Fetzer facility. Groundwater contamination from the former Fetzer facility may overlap with contamination from other sources. If necessary, a cleanup plan to address combined plume areas will be issued as a separate decision document in the future. EPA issued a unilateral administrative order to the PRP in June 2013 to design and implement the selected remedy. The PRP is currently developing the remedial design and will conduct the remediation of the facility upon completion of the design.
* Former L.A. Darling and Former Scott Fetzer Facility -- Groundwater contamination from the former L.A. Darling and Scott Fetzer facilities may extend under the North Bronson Industrial Area (discussed above). Because EPA was concerned that the high VOC levels in soils could pose a threat to the indoor air of nearby residents, a soil gas monitoring program was also implemented. Soil gas samples were collected from yards near residences and public right-of-ways that were potentially impacted. Three homes near the facilities had VOC vapors above indoor air action levels. Therefore, venting systems were installed to reduce or eliminate potential impacts to indoor air, with ongoing monitoring. VOC levels are likely to decline upon completion of remedial actions at the L.A. Darling and former Fetzer facilities, as a major source of VOCs will be reduced or eliminated by the cleanup actions. This may reduce or eliminate the need for VOC mitigation systems in adjacent residences. Decisions regarding the VOC mitigation systems will be based on additional vapor monitoring.
Property ReuseEPA is currently evaluating possible property reuse for the North Bronson former facility properties and has been coordinating this evaluation with local officials.
ContactsRemedial Project Manager, U.S. EPA
james hahnenberg (firstname.lastname@example.org)
Community Involvement Coordinator, U.S. EPA
AliasesNORTH BRONSON IND AREA
BRONSON RESIDENTS WELL
BRONSON PLATING MFG CO
BRONSON PLATING CO