Modine Manufacturing and Hulett Lagoon/Mulberry Well Sites
Last Updated: May 23, 2017
Modine Manufacturing Co. is conducting investigations of contaminant releases at the 221 Sunset Drive facility under a Corrective Action Abatement Order on Consent with the department. The department’s Hazardous Waste Program, Permits Section is providing oversight of these activities. The status of Modine’s corrective action activities is described below.
Hamilton-Sundstrand, parent company of former Sundstrand Tubular Products, is addressing related groundwater contamination issues with the Hulett Lagoon and Mulberry Well under a Cooperative Letter of Agreement with the department. The department’s Hazardous Waste Program, Superfund Section is providing oversight for these activities. The status of Sundstrand’s remedial activities is described below.
- Corrective Action Abatement Order on Consent for the Former Hulett Lagoon (03/21/16) *The web page has the correct dates. The AOC has an incorrect date, however due to it being a legal document, no correction can be made.
Because these two sites are related, Permits and Superfund are closely coordinating the investigation and corrective action/remedial activities. Modine's earlier investigations of the facility focused on soil contamination at the site. Due to advances in science and the understanding of potential health effects associated with vapors released from soil and groundwater contaminated with volatile organic compounds, the focus has shifted to investigating vapors inside the manufacturing building and nearby residential homes. The investigation began early December 2015, and was the subject of a March 2016 public meeting and April 2017 public availability session (summary). Listed below is the information provided at the two events.
- 221 Sunset Drive Factsheet (3/16)
- Trichloroethylene - ToxFAQs
- Vapor Intrusion
- Investigating Vapor Intrusion
- Facts About...Vapor Intrusion
- A Citizen's Guide to Vapor Intrusion Mitigation
- How to Reduce Your Exposure to Chemicals at Home, Work, and Play
- Aerial Photograph (3/16)
- History of the Facility at 221 Sunset Drive (3/16)
- Camdenton Area Groundwater Monitoring Wells (3/16)
- Vapor Intrusion Sampling and Mitigation Plan (3/16)
- Sampling Location Map *11 MB (3/16)
- Activities Completed to Date - Vapor Migration Assessment (3/16)
- Phase 1 Sitewide Soil Vapor Investigation Results (4/17)
- Residential Vapor Intrusion Sampling Quantities and TCE Exceedances (4/17)
- Residential Vapor Intrusion Sampling Program Exit Process (4/17)
- 221 Sunset Path Forward (4/17)
MoDNR Contact: Christine Kump-Mitchell, 314-416-2464 or 800-361-4827
Modine Contact: Jesse Nickrand, 262-636-1329
- Location of hard copies of hazardous waste permit application, orders, investigation and corrective action work plans and reports, etc. and supporting documents:
- Missouri Department of Natural Resources, Elm Street Conference Center, Missouri (Submit a Sunshine Request).
- U.S. Environmental Protection Agency, Information Resource Center, 11201 Renner Blvd., Lenexa, Kansas (Call 913-551-7241 to schedule an appointment).
- Former Company Name: Dawson Metal Products, Sundstrand Tubular Products Inc., Hamilton Sundstrand
- Type of Facility: Former Interim Status Hazardous Waste Storage – closed
- Wastes Handled: Aqueous wastes, corrosives, flammables, industrial wastewater, inorganic sludges/solids, organic sludges/solids, oxidizers, reactives, solvents, as well as various F-, K- P- and U-listed hazardous wastes as specified in the Part A application
The Modine Manufacturing Co. site is located on about 69 acres at 221 Sunset Drive (previously 179 Sunset Drive), next to a residential neighborhood in Camdenton. In 1967, Dawson Metal Products constructed a commercial building at the site and began manufacturing air-conditioning coils and feeder parts from aluminum and copper tubing. In 1972, Sundstrand Tubular Products bought out Dawson and produced aluminum and copper heat transfer units at the facility until 1990. During that time, the building underwent four expansions and is currently 120,000 square feet.
The manufacturing process required cutting and expanding aluminum and copper to bond the copper tubing with the aluminum fins. A vapor degreasing process was used to remove the oil and dirt from the various parts and assembled units before further processing. Both Dawson and Sundstrand used trichloroethylene (TCE) in the vapor degreasers. A variety of hazardous wastes were produced as part of the facility operations, including corrosive waste, wastewater treatment sludge from electroplating operations and residual contaminants associated with the degreasing operations.
From 1972 to 1990, Sundstrand stored the hazardous waste in three hazardous waste container storage areas. Area 1 was a 25 foot by 30 foot gravel area located outside, about 80 feet west of the west wall of the manufacturing building. Area 1 operated from 1972 to 1983, and stored up to forty-five 55-gallon drums of liquid waste and sludge at any given time, including TCE still bottoms, waste paint filters and liquid and non-hazardous waste oil. Area 1 was graded, paved and turned into an employee parking lot in 1983. Area 2 was a 25 foot by 30 foot concrete slab located outside, about 10 feet west of the west wall of the manufacturing building. Area 2 operated from 1983 to 1985. In addition to storing up to twenty 55-gallon drums, the area also contained one 1000-gallon waste oil tank and one 5300-gallon steel tank that held TCE still bottoms. Area 3 was a 25 foot by 50 foot area located along the south outside wall of the manufacturing building. Area 3 operated from 1979 to 1983, and reportedly stored 55-gallon drums of waste TCE and waste oil from the degreasing operations. In 1983, Area 3 was removed to make room for a building expansion to the south.
From 1967 to 1986, both Dawson and Sundstrand used four cement sumps (mud pits) for wastewater collection. The mud pits, located about 10 feet from the building foundation along the west side of the manufacturing building, were 4 feet by 4 feet by 4 feet deep. The mud pits received stormwater, boiler blowdown and cleaning line water from the manufacturing process. Each pit was connected to the pit next to it by a 6-inch diameter steel line. Mud pits #1 and #2 collected copper cleaning line waste. Mud pit #3 collected aluminum cleaning line waste. Mud pit #4, the southernmost mud pit, was an open pit that collected boiler water and stormwater. The contents of each mud pit flowed into the connected mud pit, in sequence from mud pit #4 to mud pit #1. The untreated wastewater eventually discharged from mud pit #1 into the on-site wastewater discharge line, which connected to the City of Camdenton sewer system along the north side of the manufacturing building. The untreated wastewater mixed with sanitary wastes from surrounding residential properties while it traveled to a 1-acre, off-site wastewater treatment lagoon, known as the Hulett Lagoon. Located about one-fourth mile to the northeast of the manufacturing building, Hulett Lagoon was operated by the City of Camdenton from 1961 to1989. The lagoon received stormwater and untreated wastewater from the Sundstrand facility, other commercial waste streams from the Hulett Chevrolet Buick GMC car dealership and domestic sewage from the surrounding residences. In 1985, Sundstrand removed mud pit #2, closed the Area 2 hazardous waste container storage area and installed a wastewater pretreatment system over the area. Sundstrand began using the wastewater pretreatment system in 1986 and stopped discharging untreated waste to the city sewer system.
In October 1990, Modine Heat Transfer Inc., a wholly-owned subsidiary of Modine Manufacturing Co., purchased the property from Sundstrand and continued producing aluminum and copper heat transfer units until 1997. Modine used 1,1,1-trichloroethane (1,1,1-TCA) in the vapor degreasers from 1990 until 1993, and methylene chloride from 1993 until 1997. In April 1997, Modine Heat Transfer Inc. merged with Modine Manufacturing Co. and changed its name to Modine Manufacturing Co.
In 1997, Modine completely renovated the building’s interior as part of a product-line change, which required replacing all equipment in the plant, except the wastewater and electrical systems. Modine removed the vapor degreasing units and brought all recessed floors to grade. In 1997, Modine began producing radiators (large heat transfer units) using a different manufacturing process. No chlorinated vapor degreasing was used in the parts cleaning process. In February 2009, CLA LLC purchased the property from Modine, who in-turn sold the property to RAASMartin LLC. Modine continued operating at the facility under a lease agreement until 2012.
Details regarding the removal and initial closure activities for the three hazardous waste container storage areas are unknown. In September 1990, before Modine purchased the site, Sundstrand submitted a closure plan to the department to close the hazardous waste container storage areas in order to terminate the facility’s interim status classification as a hazardous waste treatment, storage and disposal facility. Sundstrand wanted to operate as a hazardous waste generator only. Modine notified the department and the U.S. Environmental Protection Agency (EPA) of the ownership change in December 1990. According to applicable state and federal hazardous waste laws and regulations, Modine, as the owner of the property at that time, was required to investigate and clean up releases of hazardous waste and hazardous constituents to the environment at their facility resulting from present and past hazardous waste handling practices, including releases by previous facility owners.
In November 1991, Law Environmental Inc. performed an Environmental Site Assessment of the facility, on behalf of Modine. Sample results showed low levels of volatile organic compounds (VOCs) along the west side of the manufacturing building, in the area of hazardous waste container storage areas 1 and 2. Modine submitted a revised closure plan for the hazardous waste container storage areas in March 1992, which the department approved with modifications in November 1992. The modifications required additional sampling.
During this same timeframe, Jacobs Engineering Group Inc. performed a visual site inspection and preliminary assessment of the facility, on behalf of EPA, due to a complaint claiming 4500 gallons of TCE had been spilled at the facility. The assessment was conducted to identify and gather information on actual and potential releases of hazardous waste and hazardous constituents to the environment. The 1992 Environmental Priorities Initiative/Preliminary Assessment (EPI/PA) report identified six solid waste management units recommended for additional investigation. These units included the Hulett Lagoon, mud pits, three container storage areas and monorail vapor degreaser and still.
While Modine performed the container storage area closures, several investigations were also performed to assess the potential for releases from the solid waste management units recommended for additional investigation. Most of the units were grouped together by location for investigation and remediation purposes. The Hulett Lagoon and associated wastewater line were located off the Modine facility property. The mud pits, Area 1 and Area 2 were located on the west side of the manufacturing building.
Based on the 1991 sampling results, Law Environmental Inc. performed a follow-up investigation in July 1993, during the closure of the container storage areas. This investigation was to further assess the presence of TCE and related VOCs. On behalf of Modine, Law submitted a closure report in September 1993. Sampling results showed detectable amounts of VOCs and lead in the soil. The department requested Modine perform a risk assessment and additional sampling. The August 1994 Risk Assessment concluded the minimal amounts of VOCs in the soil did not pose a health risk and the lead in the soil was not considered a significant health risk. However, the department required Modine to define the extent of contamination to non-detectable levels in order to reach final closure of the container storage areas. In 1995, Dames & Moore performed the required investigation, which also included a groundwater investigation. On behalf of Modine, Dames & Moore submitted a report of its findings to the department in February 1996. Sample results showed detectable amounts of TCE and other related VOCs in and around the employee parking lot and along the buried wastewater discharge line along the west side of the manufacturing building. Additional groundwater monitoring wells were also installed. Samples taken during installation showed groundwater contamination was present. Additional investigation was determined to be needed.
In November 1996, Dames & Moore conducted an investigation at the former Hulett Lagoon to determine whether VOCs, particularly TCE, were present in the soil. Missouri Engineering Corp., a contractor for the City of Camdenton, originally coordinated the sludge removal from the lagoon during closure activities in July 1989. Although the closure was approved by the department’s Water Pollution Control Program, there was no knowledge of contamination at the lagoon at that time and the closure was not designed to meet the requirements of the Missouri Hazardous Waste Management Law and regulations regarding corrective action. Sampling results from the 1996 investigation confirmed TCE was present in the soil near the former lagoon outfall and near the center of the former lagoon.
In April 1997, Dames & Moore conducted a soil investigation under the manufacturing building floor, in the area of the monorail vapor degreaser and still and former Area 3. On behalf of Modine, Dames & Moore submitted a final report to the department in May 1997. Sample results indicated TCE was present in the soil east of the former above ground solvent storage tank location and north of the monorail vapor degreaser. VOCs were also present in the soil beneath the manufacturing building foundation, in the area of the former monorail vapor degreaser.
In September 1997, Dames & Moore performed an investigation at the mud pits to assess any potential releases. On behalf of Modine, Dames & Moore submitted a final report to the department in December 1997. Sample results showed increasing TCE concentrations with increasing depth. As a remedial action, the soil surrounding mud pits #1, #3 and #4 and debris from the mud pits (i.e., cement lining, PVC piping and scrap metal) were removed in October 1997. About 13 tons of soil were disposed off-site as hazardous waste and 184 tons were disposed off-site as special waste. The areas where VOCs were detected above the cleanup goals were limited and in areas difficult to get to for removal. Removing the soil would have potentially weakened the building foundation or damaged underground utilities, such as fire lines.
In January 1999, TCE was discovered in the City of Camdenton's Mulberry Well, at levels above the maximum contaminant level for drinking water. The Mulberry Well is a city municipal well, located about 600 feet southeast of the Modine property and 1000 feet south of the former Hulett Lagoon. A March 1999 investigation confirmed TCE from the Hulett Lagoon was released to the groundwater. Because the untreated wastewater from the Modine property mixed with sanitary wastes from nearby residences in the sewer system on its way to the Hulett Lagoon, legal limitations were imposed on the department’s ability to use hazardous waste authority to investigate the groundwater contamination. The groundwater contamination issue was referred to the department's Hazardous Waste Program, Superfund Section, under the name Hulett Lagoon. The status of these remedial activities is described below. The Mulberry Well is no longer connected to the city's water supply system and is not used for drinking water.
In July 1999, Modine entered into a Corrective Action Abatement Order on Consent with the department, Order No. 99-HW-002. The Order outlined the framework for a facility-wide investigation to fully define the nature and extent of any contaminant releases to the soil at the Modine property, and to identify and evaluate possible corrective measures necessary to prevent, alleviate or clean up any releases. The department’s Hazardous Waste Program, Permits Section is providing oversight of these activities.
Both the Modine facility and the former Hulett Lagoon appear to be contributors to the TCE groundwater contamination in the area. Permits and Superfund are closely coordinating all environmental investigation and cleanup activities, given the connection between the environmental issues.
In July 2000, as part of a plant renovation, Modine removed the on-site wastewater discharge line that connected the mud pits to the city of Camdenton sewer system. The discharge line ran along the north side of the manufacturing building, from the mud pits on the west side of the manufacturing building to the sewer main on the north side. Soil samples were collected along the base and walls of the 220-foot excavation trench. Residual TCE was detected at one sample location; however, the amount was far below the EPA Regional Screening Level for residential use. TCE was not detected in any other samples collected along the former wastewater discharge line.
In October 2000, CH2M HILL was contracted by Modine to investigate the extent of TCE contamination in the soil west of the manufacturing building, near the end of a former stormwater drain line. An approximately 4000 square foot area of the parking lot west of the building, in the former location of hazardous waste container storage Area 1, was identified as contaminated. Excavation activities began in October 2001 and included removing about 4800 cubic yards of soil. As more information became available, the amount of impacted soil was more than originally estimated, especially to the east and southeast of the known area of impact. Excavation activities stopped and additional investigations were performed to better understand the extent of impacted soil. In 2002, an additional 4700 tons of soil were removed. Confirmation sample results showed all VOC impacted soil was removed to site-specific cleanup levels, which were developed to be protective of groundwater.
On behalf of Modine, CH2M HILL performed an indoor air quality assessment for the manufacturing building in March 2003, in order to help the department complete an Environmental Indicator determination. Environmental Indicator evaluations were developed by EPA to measure the progress in protecting human health and the environment at facilities performing environmental cleanups. These measures evaluate current environmental conditions and calculate whether people are currently being exposed to environmental contamination at unacceptable levels, and whether any existing plumes of contaminated groundwater are expanding, stable, shrinking or adversely affecting surface water bodies.
The department was concerned residual VOC contamination in the soil or water beneath the manufacturing building, or along the west side of the building, could be vaporizing and entering the air inside the building. Sample results showed low VOC concentrations in the indoor air, below site-specific screening levels and the lowest OSHA occupational exposure limit. Modine continued to monitor the indoor air each year for three years and found no contaminant concentrations above OSHA occupational exposure limits. The VOC concentrations were also used to calculate cumulative risks, which were determined to be acceptable for an operating facility.
In 2006, Superfund conducted an investigation along the city sewer line, between the Modine facility and the former Hulett Lagoon. Soil sample results confirmed TCE was present in the soil along the sewer line and may be a potential source of TCE in the Mulberry Well. Superfund conducted additional investigation of the groundwater contamination related to this part of the sewer line.
During this same timeframe, CH2M HILL sampled the soil under the manufacturing building on behalf of Modine. Soil borings were advanced beneath the west wall of the manufacturing building, at former mud pits #1 and #3. A horizontal boring was advanced under the manufacturing building in the area of the former monorail vapor degreaser and still. In 2007, additional soil borings were taken through the manufacturing building floor, in the area of the former monorail vapor degreaser and still. Sample results under the manufacturing building showed VOCs were below site-specific screening levels.
As required by the corrective action order and on behalf of Modine, CH2M HILL performed a Resource Conservation and Recovery Act (RCRA) Facility Investigation to define the horizontal and vertical extent of any contamination. CH2M HILL submitted a RCRA Facility Investigation Report to the department and EPA in 2009. The report summarized the historical investigations and included both a Human Health and Ecological Risk Assessment. It also evaluated the indoor air against OSHA occupational exposure limits, which are for operating facilities and do not take into account the potential for vapors to enter from beneath the floor. Before the department would approve the report, the department determined additional indoor air investigations were necessary to determine if VOCs were vaporizing and entering the manufacturing building. In August 2010, indoor and outdoor air samples were collected at the facility. The maximum TCE concentration was below the screening level based on EPA’s preliminary TCE toxicity values.
In March 2012, Modine stopped operating and removed all equipment and machinery from the building. Modine vacated the premises and terminated its lease in late April 2012. In 2013, CH2M HILL submitted to the department a Quality Assurance Project Plan, on behalf of Modine, for indoor air and sub-slab soil gas sampling in the manufacturing building. The actual sampling was delayed due to a change in property ownership and technical difficulties with the building’s ventilation system. The property went into foreclosure in 2013. The current lienholder is Simmons First National Bank. The facility is currently vacant and property is inactive, except for on-going corrective action activities.
During this same time period, EPA released final TCE toxicity values, which resulted in lower screening levels than were used in the 2003 and 2010 indoor air sampling events. In March 2015, CH2M HILL collected sub-slab soil gas samples beneath the manufacturing building in areas not previously sampled, indoor air samples inside the manufacturing building and outdoor air samples just outside the manufacturing building. On behalf of Modine, CH2M HILL submitted a Vapor Intrusion Evaluation Summary Report to the department in June 2015. Sample results showed TCE concentrations in the indoor air above the department’s risk-based target level for non-residential land use and EPA’s regional screening level for industrial air. TCE concentrations in the sub-slab soil gas were above EPA residential and commercial screening levels. TCE was not detected in the outdoor air sample collected upwind of the building; however, TCE was detected downwind of the building. The TCE concentrations detected in the outdoor air did not appear to be a source of the measured indoor air concentrations. The TCE concentrations in sub-slab vapors were extremely high. It was suspected these vapors were entering the manufacturing building and were the main source of the measured indoor air concentrations.
Because of these findings, CH2M HILL, on behalf of Modine, performed outdoor soil gas sampling in July and August 2015, on the eastern and northern facility property lines, next to the nearby residential areas. CH2M HILL submitted a Vapor Intrusion Evaluation Summary Report to the department in October 2015. Sample results showed the maximum TCE concentrations in soil gas at the eastern facility property line were above EPA residential and commercial screening levels. The sampling location was about ten feet west of a residential property and 80 feet south of an existing sanitary sewer line serving the nearby residences. TCE concentrations in soil gas near the sanitary sewer line on the northern side of the building were above EPA residential screening levels. The sewer line runs east from the manufacturing building into a sewer tie-in drain, where it splits north to Sunset Drive and east to Mulberry Drive (the neighborhood to the east of the facility property). The sample results suggested the possibility of TCE vapors entering the sewer line or backfill material surrounding the line, which could act as a pathway for TCE vapors to enter the nearby homes and build up to levels of potential health concern. Based on these sample results, the department requested Modine to obtain access to and perform indoor air and sub-slab soil gas sampling at select homes north of the facility property on Sunset Drive, east of the facility property along Mulberry Drive and any other nearby homes connected to the sewer line. The department also requested Modine to collect soil gas samples from the gravel subgrade along the sewer line along the length of Mulberry Drive and another round of soil gas samples from the previously sampled locations on the facility property.
Quarterly sampling events were conducted at each residence, in order to evaluate the potential effects of temperature changes on vapor intrusion. The first sampling event occurred in early December 2015, with supplemental sampling conducted in January 2016. Indoor air and either sub-slab or crawl space soil gas samples were collected at each residence where access for sampling had been granted. Sewer gas samples were collected within the sewer lines. Soil gas samples were planned in the gravel subgrade along the sewer corridor, but were not collected due to heavy rain and water in the sampling ports. Sample results showed TCE concentrations below the EPA regional screening level in seven of the ten residences. TCE concentrations at three residences were above the regional screening level, but below the response action level. In order to further evaluate the indoor air and potential TCE sources, a HAPSITE, which is a mobile instrument used to detect VOCs, was used at the three residences that exceeded the regional screening level. TCE concentrations exceeded the sub-slab soil gas screening level at one residence; therefore, a sub-slab mitigation system was installed.
Based on the results of the December/January sampling events, the department requested Modine expand the residential sampling scope by obtaining access to and performing indoor air and sub-slab soil gas sampling at select homes north of Sunset Drive, along Bent Tree Lane. The next sampling event occurred in March 2016, and included the selected residences along Bent Tree Lane and the residences sampled in December 2015. Indoor air and either sub-slab or crawl space soil gas samples were collected at each residence. Soil gas samples were collected in the gravel subgrade along the sewer corridor, where possible, and sewer gas samples were collected within the sewer lines. Sample results showed TCE concentrations above the response action level at one residence on Mulberry Drive. An air-purifying unit was installed at this home and permanent vapor mitigation will be installed.
Quarterly sampling continued in June 2016, September 2016 and December 2016. Residences that complete four quarters of indoor air and sub-slab or crawl space sampling, with sample results showing TCE concentrations below the response action level, are eligible to be removed from the quarterly sampling program. Modine developed an exit process for those residences. As of February 2017, eighteen residences completed the quarterly sampling program.
Sundstrand operated three hazardous waste container storage areas under the interim status portions of the federal and state hazardous waste laws, 40 CFR Part 265 and 10 CSR 25-7.265. When Congress passed the federal hazardous waste law in 1980, all existing facilities treating, storing or disposing hazardous waste in a manner that would necessitate obtaining a hazardous waste permit were required to notify EPA and apply to get such a permit, unless the facility chose to close those operations. Because of the large number of existing facilities, Congress set up requirements which allowed these facilities to operate temporarily under “interim status” until they received their permit.
Sundstrand (now Hamilton-Sundstrand) submitted their RCRA Part A Permit Application for the hazardous waste container storage areas on Nov. 10, 1980, with a revision submitted in 1983. A RCRA Part B Permit Application was never submitted. In September 1990, Sundstrand decided not to continue the hazardous waste permitting process and to close the hazardous waste container storage areas. Sundstrand wanted to operate as a hazardous waste generator only. Sundstrand, and later Modine, is not subject to the permitting requirements of the Missouri Hazardous Waste Management Law or federal Hazardous and Solid Waste Amendments to RCRA for post-closure care because they “clean closed” the interim status hazardous waste management units.
Modine is subject to corrective action because they completed closure of the interim status hazardous waste management units after the effective date of the federal Hazardous and Solid Waste Amendments to RCRA. On July 20, 1999, Modine voluntarily entered into a Corrective Action Abatement Order on Consent with the department, Order No. 99-HW-002. The order is still in effect.
MoDNR Contact: Don Van Dyke, 573-751-4187 or 800-361-4827
Sundstrand Contact: Brad Barquest, 763-274-8130
- Location of hard copies of orders, investigation/remediation work plans and reports, etc. and supporting documents for Hulett Lagoon/Mulberry Well :
- Missouri Department of Natural Resources, Elm Street Conference Center, Missouri (Submit a Sunshine Request).
- U.S. Environmental Protection Agency, Information Resource Center, 11201 Renner Blvd., Lenexa, Kansas (Call 913-551-7241 to schedule an appointment).
Mulberry Well's Water Treatment System
In order to ensure the TCE plume remains contained and does not spread to other city or private wells, a water treatment system has been created to aerate the TCE out of the water and into the air. Water is discharged by the Mulberry Well pump and exits through a perforated PVC pipe contained in a plastic culvert. This is where you see in the picture on the right water being sprayed in many directions from the white circle. By having the water sprayed from the pipe, it is aspirated which adds air to evaporate the TCE.
The aspirated water then exits through a series of corrugated plastic troughs with spaced rocks to aid the aspiration of the water. As the water flows down the hill, it flows over and around rocks, over the ridges of the corrugated plastic and runs off each trough to the next, all of which add air to help evaporate the TCE.
Testing has shown that all TCE has been removed from the water prior to discharge from the system into the stream. The current investigation activity for the Mulberry Well is to find the depth at which the contamination is occurring. This would allow the city to only pump out the contaminated water zone while sealing out the uncontaminated zones. By doing that, it would then lessen the amount of water that has to be pumped to keep the contamination from spreading to other private or public drinking water wells in the area.
The Former Hulett Lagoon site is a closed 1-acre, wastewater treatment lagoon located in Camdenton, 500 feet northeast of the intersection of Dawson Road and Sunset Drive. From 1961 to 1988, Hulett Lagoon was operated by the city of Camdenton. From 1967 to 1989, the lagoon received domestic sewage from the surrounding residences, stormwater and untreated wastewater from the Sundstrand facility (now Modine facility) and other commercial waste streams from the Hulett Chevrolet Buick GMC car dealership. The city closed the lagoon in July 1989, by draining the water and removing the sludge. The site is currently an open field area with grassy vegetation, located in a mixed residential/commercial area.
In November 1996, Dames & Moore conducted an investigation at the former Hulett Lagoon in conjunction with investigations occurring at the Modine Manufacturing facility. The investigation was to determine whether VOCs, particularly TCE, were present in the soil. Although the lagoon closure was approved by the department’s Water Pollution Control Program, there was no knowledge of contamination at the lagoon at that time and the closure was not designed to meet the requirements of the Missouri Hazardous Waste Management Law and regulations relative to remedial action. Sampling results from the investigation confirmed TCE was present in the soil near the former lagoon outfall and near the center of the former lagoon.
In March 1993, TCE was first discovered by the Missouri Department of Health in the City of Camdenton’s Mulberry well, at a level below the maximum contaminant level (MCL) for drinking water (5 parts per billion, ppb). The department analyzed samples collected by the city of Camdenton in April 1994 and TCE was not detected. As required by the three-year monitoring cycle for volatile organic compounds, the well was next sampled in January 1997 and TCE was detected below the MCL at 3.8 ppb. The Mulberry well continued to be sampled quarterly in 1997; all the results were below the MCL. In February 1998, TCE was first detected above the MCL at 6.3 ppb. The Mulberry well is located about 600 feet southeast of the Modine property and 1000 feet south of the former Hulett Lagoon. The Mulberry well was the highest producing well of Camdenton's public drinking water system, supplying approximately 2107 people. Due to the TCE contamination, the city officially took the Mulberry well off line in January 1999. At that time, the Mulberry well showed TCE at 26.2 ppb and a monitoring well located immediately near the lagoon contained TCE at 1400 ppb. The Mulberry well is no longer connected to the city's water supply system and is not used for drinking water. With the department's approval, a water permit was issued to the city so the well could be periodically pumped, treated and discharged to a nearby tributary. This is being done to maintain hydrologic control of the contamination, to prevent the contamination from spreading to the other city wells. The water permit requires regular sampling and allows a discharge limit of up to 80 ppb. Currently, the well water is below the discharge limit.
In 1999, the Hazardous Waste Program's Superfund Section conducted a Combined Preliminary Assessment/Site Inspection (PA/SI) at the former lagoon. Groundwater sampling results documented a release of TCE to the Ozark Aquifer, in the area of the former Hulett Lagoon site. As past owner and operator of the manufacturing facility (now Modine Manufacturing), Sundstrand Tubular Products discharged untreated wastewater, including TCE and other volatile organic compounds, to the Hulett Lagoon. In 2000, Hamilton-Sundstrand, parent company of former Sundstrand Tubular Products, entered into a voluntary letter of agreement with the department, in order to enter Superfund’s State Cooperative Program to conduct a Remedial Investigation/Feasibility Study (RI/FS). The study is being conducted to investigate groundwater contamination caused by historic releases of TCE and other volatile organic compounds at the former Hulett Lagoon site and to evaluate possible remedial action alternatives. The department’s Hazardous Waste Program, Superfund Section is providing oversight of these activities.
For the most part, the RI was complete in 2010; however, during the negotiations for the remedial action it was determined supplemental investigation work was necessary to properly assess the remedial action alternatives. Both the Modine facility and the former Hulett Lagoon appear to be contributors to the TCE groundwater contamination in the area. Permits and Superfund are closely coordinating all environmental investigation and cleanup activities, given the connection between the environmental issues.
In 2000, Hamilton-Sundstrand, parent company of former Sundstrand Tubular Products, entered into a voluntary letter of agreement with the department, in order to enter Superfund's State Cooperative Program. In March 2016, Hamilton Sundstrand Corp. (a subsidiary of United Technologies Corp.), Modine Manufacturing Co. and the City of Camdenton entered into an Administrative Order on Consent* with the department. The city is a responsible party since they owned and operated the former Hulett Lagoon.
*The AOC has an incorrect date; however, due to it being a legal document, no correction can be made. The dates listed on this web page are correct.