The 1999 report - a massive 572-page document uploaded to MDNR's public website in late May under Modine Heat Transfer Inc. and Hulett Lagoon/Mulberry Well Sites - details questionable actions by former city officials and warned of the potential dangers of failing to secure the toxic plume.
A Combined Preliminary Assessment / Site Inspection Report conducted by the Missouri Department of Natural Resources from March 1999 regarding the extent, contributing sources and potential impact of trichloroethylene (TCE) contamination in Camdenton sought to answer the same questions citizens and officials are still left with today.
What caused the TCE contamination? How deep and widespread did the TCE reach? What can be done to prevent further migration?
Those were some of the main questions Valerie H. Wilder, an investigator with MDNR’s Division of Environmental Quality Hazardous Waste Program who performed the initial PA/SI inspection report on behalf of the Environmental Protection Agency, sought to answer.
The chemical, a degreasing solution used to clean large metal equipment for nearly three decades by manufacturers at the facility located at 179 Sunset Drive, is considered a human carcinogen.
The 1999 report - a massive 572-page document uploaded to MDNR’s public website in late May under Modine Heat Transfer Inc. and Hulett Lagoon/Mulberry Well Sites - details questionable actions by former city officials and warned of the potential dangers of failing to secure the toxic plume.
The report was ultimately submitted to the EPA and later approved for Superfund site designation of the former lagoon.
The first reported problems of the Hulett Lagoon - also referred to as the Factory Lagoon or Camdenton Lagoon - came on Sept. 7, 1978 during an MDNR inspection when the inspector noted that the lagoon had a large problem with its industrial influent. The lagoon has no ownership connection with the local family of the same name, but has been historically referred to as Hulett Lagoon due to its proximity to the Hulett car dealership.
According to provided documentation, the inspector told the city that the treatment time for the industrial waste was far too short a period to treat the waste effectively. The inspector recommended moving the sewer lines to a different location and “recommended to the city they enforce their sewer use ordinance to prevent misuse of the sewers and sewage treatment facilities.”
The former lagoon site is a closed wastewater lagoon operated by the city from 1961 to 1988. It featured an influent pipe from a city sewer line from the north side and an influent pipe from the industrial manufacturing facility from the south side. It was the only one of five Camdenton lagoons that received industrial effluent in addition to domestic sewage.
“The Ron Hulett car dealership personnel have reported unauthorized dumping in the wooded area behind their facility that borders the road leading down to the lagoon,” Wilder noted in her report. “The untreated wastewater was known to have contained several hazard waste streams including corrosive waste, wastewater treatment sludges from electroplating operations, and waste oil. In addition, residual contaminants associated with degreasing operations, including TCE, was discharged in the mud puts and ultimately Hulett Lagoon.”
When the MDNR inspector visited the lagoon in 1978, he observed “effluent from the metal fabricating plant bubbling up approximately 40 feet from the discharge pipe. There was an area of thick floating effluent. Discharge from the lagoon was dark green in color with thick white foam floating on the surface,” according to the 1978 inspection report.
In May 1984, the city collected samples of Hulett Lagoon water that showed 41 parts per billion (ppb) TCE in the Sundstrand influent and 228 ppb TCE in the effluent from the lagoon. In 1988, the city began closure through a dual-grant sought by Sundstrand and the city to excavate the sludge to a city-owned sludge disposal area located by the municipal airport.
Lime was added to the sludge to raise the pH levels and immobilize the metal, but unusually large rain did not dry out and shrink the sludge. Each rain would then spread contamination to more soil. The lagoon had to be pumped again and allowed to be dried and a small amount of additional soil had to be removed, bringing a total of 2,395 cubic yards of sludge and soil removed.
Near the end of the hauling process, a Camdenton Public Works employee reported to MDNR that he observed the contractor “took the last several piles of sludge material and simply dumped them in the ditch located about 50 feet north of the circular storage. It was not spread, mixed or disced,” according to written documentation provided in the report.
There were concerns that the TCE spread to more soil at the lagoon, but further testing showed minimal levels at the time. Now nearly two decades later, any amount likely would be forced underground, the report stated.
In 1986 when the City of Camdenton was planning a new waste treatment facility, the city underwent a pretreatment compliance audit by MDNR, which recommended officials “establish, document, and implement formal sampling procedures; have adequate personnel; pursue enforcement actions as specified by the federal pretreatment regulations; establish local limits of waste usage; and update city ordinances with federal policies before submitting all changes to DNR for approval,” according to documentation provided in the report.
In 1992, MDNR conducted a PA/SI of the facility being operated by Sundstrand that was initiated by a complaint filed with MDNR alleging that 4,5000 gallons of TCE had been spilled at the facility. At the time, there were other investigations occurring through EPA contractors and Modine consultants.
According to further documentation by The Dames and Moore Group, a company consulting on behalf of Modine, that allegation as well as others involving alleged dumping was never confirmed or verified by MDNR.
“In general, all of the investigations documented and or confirmed the presence of chlorinated solvents, including TCE, in the soils and groundwater at the facility,” Wilder noted. “A dye trace study of the sewer system performed by DNR on Aug. 1998 verified that facility wastewater mixes with domestic sewage prior to entering city property.”
Analytical results at the time from soil and groundwater sampling showed TCE at concentrations above Super Chemical Data Matric health-based benchmarks as well as the Maximum Contaminant Level for drinking water of 5 ppb.
Wilder concluded that TCE groundwater contamination in the area could not be fully determined, but identified four sumps, or mud pits, at the facility as possible contributors. According to geological analysis, Wilder concluded that the Ozark Aquifer was considered exposed at the surface at the former lagoon site. MDNR disputed a claim by Modine’s consultants of the migration path of the contaminant.
“According to DGLs geologists, assertions made by Modine’s consultants that preferential pathways in the Ozark Aquifer substantially influence flow direction in the saturated zone are incorrect. Water flows downhill; fractures or solution-enlarged channels cannot make water flow uphill,” Wilder wrote. “Baseline and pumping rate data needs to be collected before informed decisions about groundwater movement in the subsurface can be made.”
The discovery of TCE in Camdenton’s Mulberry Well was a great cause of concern for MDNR and one of the main factors considered by the EPA in determining that the Hulett Lagoon qualified as a Superfund Site.
“The Mulberry City Well (which was shut down on January 26, 1998, because of TCE contamination) produced approximately three times the volume of the other two city wells, suggesting the aquifer is highly heterogeneous. Any potential site-related contaminants reaching the water table are expected to move toward the nearest Camdenton City Well,” according to the report.
The Mulberry Well was supplying approximately 70 percent of the city’s total water supply until July 1998, when additional water controls were added that cut the consumption of the well to approximately 40 percent.
The first time TCE was detected in the Mulberry Well was March 1993, and result samples to be submitted to MDNR began in January 1997 under a quarterly monitoring program. During the 1997-1998 sampling there was only one sample that exceeded the MCL, but the running average for the year was below.
In 1998, the presence of TCE began to increase as the city was planning to bring the new Hickory Well online.
“PA/SI sampling has documented an observed release of TCE to the Ozark Aquifer in the area of the former Hulett Lagoon site. There are two sources of TCE that could be attributed to the contamination present in the the Mulberry Well,” Wilder concluded. “Hulett Lagoon contains TCE contaminated soil, as well as groundwater. Information on groundwater flow is inconclusive. Now that the Mulberry Well has been shut off, groundwater flow is expected to move toward another, most likely Blair.”
Wilder estimated a four to seven foot depth zone of TCE contamination in the lagoon and recommended the city pursue additional security for the site in light of alleged illegal dumping and trash discovered at the site. At the time the area was not fenced or gated off.
“It is presumed that the majority of TCE, once deposited in the lagoon, has infiltrated the bedrock. However, the TCE contaminated soil that remains in the lagoon may be a continuing source of contamination,” Wilder noted. “Remaining wells are now at risk, hydraulic control will need to be achieved at the source of the plume to prevent the migration of TCE.”
While current officials with the city of Camdenton said in April 2017 that the Mulberry Well had not been turned back online since Jan. 26, 1998, MDNR documented two instances when the well was online due to issues with water control and electrical problems.
“Since February 2, 1999 the Mulberry Well has been on-line twice. Due to electrical problems at the Blair Well, Mulberry Well was pumped from Feb. 2-9, 1999, for a total of about 400,000 gallons. Due to problems with the water control, Mulberry Well was pumped from Feb. 12-16, 1999, for a total of 1,314 gallons,” according to a handwritten note from former Camdenton Public Works Director Vince Costa.
At the recommendation of MDNR in 1999, Camdenton eventually began pumping the Mulberry Well using an air-stripping method to dissolve the TCE, and the same method is still used today.
“The current investigation activity for the Mulberry Well is to find the depth at which the contamination is occurring,” according to notes provided by MDNR regarding status of the well. “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 answer on the extent of the contamination is expected to come in the form a report due to MDNR in August from an engineering firm contracted by the city. Mayor John McNabb said approximately two months ago during a press conference that the report would detail the extent of the contamination and offer recommendations for the city to address the issue once and for all.
The report is also supposed to detail the City of Camdenton’s financial responsibilities for the investigations and clean up efforts on behalf of MDNR.