Missouri Metals - Elmwood Park Neighborhood
The Missouri Metals Fabrication Facility is located at 9970 Page Avenue in Overland. The facility began operation in 1957 and has manufactured aircraft component parts under various ownerships. Volatile organic compounds (VOC) such as Tetrachloroethylene, known as PCE, and trichloroethylene, known as TCE were used as solvents and metal degreasers as part of the manufacturing process. The first environmental sampling at the facility was completed by the department in 1987. This sampling documented metals and VOCs, in soil on site. Sampling conducted by EG&G, who purchased Missouri Metals, documented VOCs in groundwater on site in 1988. The Missouri Department of Health and Senior Services, or DHSS, provided a health assessment at that time that concluded the site should not present a risk to the employees working there or to permanent residents who live nearby.
EG&G conducted more groundwater sampling in 1991 on site and documented high levels of VOCs that included PCE, and TCE. Due to the high levels of PCE and TCE documented in groundwater on-site the department proposed the site for the Missouri Registry of Confirmed Abandoned or Uncontrolled Hazardous Waste Sites. DHSS provided a second health assessment in 1991 and determined there was no immediate health threat to the general public. This health assessment was based on the contamination being present in the shallow ground water and there was no use of this water for drinking purposes. This area’s drinking water was and continues to be serviced by Missouri American Water Company of St. Louis County. EG&G appealed the registry listing and conducted more environmental investigations on-site and submitted a report to the department in 1993. The department and EG&G negotiated a consent agreement that required additional investigations and implementation of a remedial action. In 1994 during negotiations, DHSS was asked to up-date their last health assessment. DHSS concluded its previous conclusions were still applicable since there was no use of groundwater in the area.
In 1998 PerkinElmer purchased the facility and assumed responsibility for the environmental obligations in the 1994 consent agreement. Over time, this type of contamination in soil and groundwater can migrate or spread out depending on the type of soil and geology present. The department directed PerkinElmer to conduct off-site sampling in the nearby Chicago Heights neighborhood. Soil and groundwater contamination was documented off-site. Concerned with migration of contamination, the department’s Hazardous Waste Program conducted assessments and samplings from 1998 to 2001. These assessments evaluated the vapor intrusion pathway off site in the neighborhood. On November 19, 1998 the department held an informational meeting to discuss off-site migration of groundwater and the TCE vapors that were identified in several homes. A health consultation was requested from DHSS based on these assessments. The department explained ongoing site work to neighborhood residents by speaking at the Concerned Citizens of Elmwood Park neighborhood meetings in 1999, 2001 and 2003. DHSS concluded levels were not a concern based on screening levels for PCE and TCE at that time in a health consultation report.
In 2003-2004 PerkinElmer attempted to remediate on-site soil using chemical oxidation. In 2005 PerkinElmer sampled on-site and off-site groundwater wells and submitted a remedial action summary report in 2006. Results indicated contaminants were still present although some levels on site decreased while some levels off-site increased. PerkinElmer believed the site could be closed under a risk based corrective action process and claimed in this report that other sources of contamination may be contributing to the off-site detection of contaminated groundwater at some locations based on geologic migration and other factors. During this time period PerkinElmer also submitted a human health baseline risk assessment report. Off-site vapor migration was not evaluated in this risk assessment.
In 2006-2009 technical comments between the department and PerkinElmer were ongoing in regards to the remedial action summary report. Comments on the human health risk assessment were also prepared by the DHSS. As a result of this review by the department and DHSS, the department reiterated its concerns regarding off-site migration of contaminants and directed PerkinElmer to prepare a comprehensive plan to re-assess shallow groundwater and the potential for vapor intrusion using current vapor intrusion science in the off-site areas.
PerkinElmer submitted the first draft of the supplemental investigation work plan in 2010 to conduct off-site shallow groundwater and vapor intrusion sampling. After several responses to comments and subsequent revisions, the department approved the supplemental investigation work plan in July, 2011 to conduct shallow groundwater sampling. Twenty-eight temporary shallow groundwater wells were sampled within the off-site residential neighborhood. The department evaluated the sampling results to develop in-home vapor intrusion sampling locations based upon location of shallow groundwater contamination.
The department approved the supplemental investigation work plan in April 2012 to conduct in-home vapor intrusion sampling after multiple comments and revisions and clarifications. To investigate the effect of air inside homes, three rounds of sampling were recommended to address year round conditions. PerkinElmer conducted the first of three rounds of in-home vapor intrusion sampling in May 2012 on 10 properties, which included seven homes and three apartments. In-home samples of basement air, sub-slab soil gas, sump water and sump air were collected on those properties with basements and indoor air and sub-slab soil gas on those properties without basements. Prior to conducting the in-home sampling, the department notified residents in writing and the department, DHSS and PerkinElmer’s environmental contractor met personally with each of the 10 residents to discuss the in-home sampling. In-home sampling was completed the second week of May 2012. Based on the results of the first round of sampling, DHSS notified the department that exposure was likely occurring inside two homes and recommended actions must be taken to mitigate exposure risk to residents. Sampling results were evaluated using the updated toxicological numbers for TCE and PCE that were finalized in September 2011 and February 2012. On July 31, 2012, the department referred the off-site Chicago Heights Boulevard VOC Plume Site to the Environmental Protection Agency, or EPA, for a time-critical removal action to mitigate the potential exposure threat to residents.
The Housing Authority of St Louis County hosted an informational meeting on August 9, 2012 at the First Baptist Church of Elmwood, to discuss the purpose for additional sampling and the possibility of removal actions. Three presentations were made, one by the department, one by DHSS and one by EPA.
A second round of in-home sampling was conducted by PerkinElmer in August 2012. The department directed PerkinElmer to sample the main floor level air inside those homes with basements, in addition to those locations sampled previously in round one. In-home air sample results confirmed the presence of contamination and showed airborne concentrations similar to the first round sampling results.
In September 2012, the department referred the on-site Missouri Metals facility to EPA due to EPA’s expanded regulatory ability to facilitate expeditious remedial action. Through this action EPA became the lead regulatory agency in working with the responsible party. The department will coordinate and assist EPA as additional investigations and cleanup actions are completed.
EPA held open house-style listening post sessions on September 12 and 13, 2012 to allow residents of Elmwood Park to ask questions and receive information about the site investigation and vapor issues. The Department, the Missouri Department of Health and Senior Services and the Agency for Toxic Substances and Disease Registry also assisted at these sessions. EPA plans to hold future meetings in the neighborhood to explain ongoing actions. It is expected the next meeting will be in October 2012.
What is TCE?
Trichloroethylene is a nonflammable, colorless liquid. It is used mainly as a solvent to remove grease from metal parts, but it is also an ingredient in adhesives, paint removers, typewriter correction fluids and spot removers. At the Missouri Metals facility it was used historically to clean aircraft component parts that were manufactured at the facility.
For more information or questions contact:
- Dan Gravatt - Environmental Protection Agency - 913-551-7324
- Jonathan Garoutte - Missouri Department of Health and Senior Services - 573-751-6102.
- Wane Roberts - Missouri Department of Natural Resources - 573-526-7309
Aug. 9 Presentations
- Department of Natural Resources PowerPoint® - revised Oct. 31, 2012.
- Department of Health and Senior Services PowerPoint®.
- May and August 2012 residential analytical results and historical results.
- Vapor intrusion investigation map.
- TCE map for shallow groundwater.
- PCE map for shallow groundwater.
- EPA Chicago Heights webpage.
- Chicago Heights Listening Post Sessions.
- Volatile organic compounds.
- Vapor intrusion and the Superfund Program.
- Vapor intrusion fact sheet - provided by the Department of Health and Senior Services.
- What you should know about vapor intrusion.