WELDON SPRING EPA Region 7 03/12/2010 FORMER ARMY f if™' ^ County: St. Charles County ORDNANCE Other Names: Weldon Springs National WORKS Guard Facility, [V,,ccnilRl US Army Trainin" Ccntcr' Weldon Springs-Ex Army Ordnance Plant, EPA ID# MO5210021288 Ft. Leonard Wood SITE DESCRIPTION The Weldon Spring Former Army Ordnance Works site occupied more than 17,000 acres and operated from 1941 to 1944. During its operation, the site produced explosives including trinitrotoluene (TNT) and dinitrotoluene (DNT) for the U.S. Armed Services. A series of land transfers left the Army with 1,655 acres, which it has operated since 1959 for the Army Reserve as the Weldon Spring Training Area. Contaminated areas are spread throughout the 17,000 acres of the site, with the greatest concentration in the Training Area. Some of the transferred land that covered two small areas of the original Ordnance Works area now are owned by the U.S. Department of Energy (DOE) and listed on the National Priorities List as Weldon Spring Quarry/Plant/Pits site. Investigations have identified a number of potentially contaminated areas, including seven unlined lagoons where TNT wastewater was stored, TNT production lines, two DNT production lines, drainage ditches below TNT production lines, and eight areas where explosive wastes were burned. Approximately 5,000 people live within 3 miles of the site, and approximately 70,000 people obtain drinking water from St. Charles County wells located within 3 miles of the hazardous substances at the site. Surface water in the area flows either to the Mississippi River watershed to the north or the Missouri River watershed to the south. Surface waters located within 3 miles are used for recreational activities. Site Responsibility: This site is being addressed through Federal actions. NPL LISTING HISTORY Proposed Date: 07/14/89 ------- Final Date: 02/21/90 Deleted Date: THREATS AND CONTAMINANTS In 1987, a Department of Defense (DoD) investigator found explosives such as TNT and DNT in monitoring wells near the lagoons. TNT, DNT, and lead have been identified in soil at several areas on the site, and TNT was detected in 1987 in surface water downstream of the lagoons. The Mississippi watershed, which supports wetlands, wildlife, and recreational activities, may be threatened by run-off from the site. The TNT and DNT contamination on the site represent a physical hazard with some potential for explosion. Ingestion of polluted surface water, ground water, or contaminated soil may pose a threat to human health. DNT is a probable human carcinogen and may be absorbed through direct contact. CLEANUP APPROACH Response Action Status Initial Actions: In late 1992, the U.S. Army Corps of Engineers removed the interior wooden boards of a storage room used by the Francis Howell School District. This storage room was a box factory during the operation of the former Ordnance Works during World War II. Explosive contaminants were discovered within the interior wooden boards after wipe samples from the building were taken. The interior wooden boards were removed and replaced with sheetrock. As part of a removal action, Burning Ground #1 was fenced to eliminate any potential exposures while investigative actions are ongoing. Surface chunks of TNT have also been removed from the burning grounds to eliminate any direct contact threat. Entire Site: In 1987, the DoD identified a number of contaminated areas on the site. Under EPA direction, DoD began a complete investigation into the nature and extent of contamination at the site in early 1990. The study, which led to the selection of a final cleanup remedy, was divided into two Operable Units (OUs). Operable Unit 1 (OU1) addressed surface soil, buried wooden pipeline, and various structures, and was completed in 1996, leading to a cleanup of the various source areas with a final report in September 2004. The primary remedy for OU1 was source removal and destruction by incineration. Materials unsuitable for incineration were stabilized and landfilled, in two instances some TNT was removed to a permitted facility and detonated. Operable Unit 2 (OU2) of the study addressed ground water contamination and assessed the impact from the source removal remedy (OU1) on the ground water contamination. As a result of the ground water study, a monitored natural attenuation remedy with institutional controls to as & '/YV / ------- prevent future exposures was selected for the ground water contamination at the site in September 2004. The site was placed in a construction complete category in September 2005, indicating that all active construction to protect human health and the environment has been accomplished. Monitoring of site ground water and implementation of institutional controls will continue for the foreseeable future. Site Facts: This site participated in the Installation Restoration Program (IRP), a specially-funded program established by the DoD in 1978, to identify, investigate, and control the migration of hazardous contaminants at military and other DoD facilities. The site was funded by IRP in FY05 ------- ENVIRONMENTAL PROGRESS The Record of Decision (ROD) for OU1 (Source Areas) was signed September 26, 1996. Incineration of TNT-contaminated soils and wooden pipeline as the remedy was selected and was completed in June 2004, with a final report in September 2004. Contaminated materials unsuitable for incineration were decontaminated, stabilized, and disposed of in a containment cell on-site or transported to a suitable RCRA-permitted facility. The ROD for Operable Unit 2 (Ground water) was signed on September 30, 2004. Monitored natural attenuation of contaminated ground water with institutional controls to prevent future exposures was the selected remedy. The ground water monitoring efforts will be ongoing for the foreseeable future. The contaminated ground water plumes have not migrated past the site boundries. The ground water is monitored annually and the remedy continues to be protective of human health and the environment. The site was considered "Construction Complete" as of September 30, 2005. COMMUNITY INVOLVEMENT Review and evaluate community involvement documents, as needed. Fact sheets and other documents can be accessed at the following link - http://www.nwk.usace.army.mil/projects/weldon/newsletters.htm ------- SITE REPOSITORY St. Charles City/County Library Superfund Records Center District 901 N. 5th St. Middendorf-Kredell Branch Kansas City, KS 66101 2750 Hwy K Mail Stop SUPR O'Fallon, MO 63366 (913)551-7166 REGIONAL CONTACTS SITE MANAGER: E-MAIL ADDRESS: PHONE NUMBER: COMMUNITY INVOLVEMENT COORDINATOR: PHONE NUMBER: E-MAIL ADDRESS: STATE CONTACT: PHONE NUMBER: Hoai Tran/R7/U SEPA/U S tran.hoai@epa.gov (913)551-7330 Beckie Himes (913)551-7253 himes.beckie@epa.gov Brandon Doster (573)-526-2739 MISCELLANEOUS INFORMATION STATE: MO 07BC CONGRESSIONAL DISTRICT: 09 EPA ORGANIZATION: SFD- SUPR/IANE MODIFICATIONS Created by: Karla Created Date: 10/17/97 02:29 PM Asberry/SUPRFUND/R7/US EPA/US Last Modified by: Dianna Last Modified Date: 03/12/2010 09:07 AM Whitaker/R7/U SEPA/U S ------- |