EPA Superfund Site

AIR FORCE PLANT PJKS

CO | EPA ID CO7570090038

About this site’s exposure pathways: As of September 2025, the former Air Force Plant PJKS Superfund site (Site) is considered Insufficient Data to make a Human Exposure evaluation (HEID) because of a newly identified exposure pathway and/or contaminant(s). The Air Force originally owned the Site, which is entirely within the boundaries of the Lockheed Martin Space Systems (LMSS) 5,200-acre industrial facility. LMSS purchased the Site; however, the Air Force retained responsibility for the cleanup of the Site. LMSS employs fences and security personnel to enforce strict rules that prohibit unauthorized personnel from entering the site. The nearest current residents to the Site are located either 4000 feet to the northwest (upgradient) of the site or more than a mile downgradient. There is per-fluor-alkyl substances (PFAS) contamination of groundwater at the site, as well as potential contamination of soil.
The extent of the PFAS contamination is not yet known and there is potential for human exposure via incidental ingestion of contaminated soils and ingestion of groundwater containing PFAS. Ingestion of contaminated groundwater at and near the Site is prevented through a Colorado Department of Public Health and Environment (CDPHE) Restrictive Notice, which prohibits residential land use and use of groundwater for anything other than monitoring. The footprint of the prohibition may need to be extended, depending on the extent and levels of PFAS groundwater contamination. Soil remediation may also be needed if unacceptable levels of contamination soils are observed to protect workers at the Site. Additionally, the groundwater underlying the site is contaminated with the chlorinated solvent trichloroethene (TCE) and its degradation products, which could result in human exposures through inhalation via vapor intrusion into buildings above the contaminated groundwater. This pathway was thought to be negligible at the time of the Record of Decision (ROD); however, a study in 2020 found relatively high concentrations in air near existing buildings on the site. Depending on the levels of TCE and tetrachloroethylene (PCE) in indoor air, vapor mitigation may be necessary.
The EPA uses the HEID status when there is a lack of evidence to suggest that actual or reasonably anticipated human exposures are occurring, and that those exposures are above acceptable risk-based levels. The planned activities to collect sufficient information to evaluate this new exposure pathway and⁄or contaminants(s) are 1) a remedial investigation (RI) to define the extent and magnitude of PFAS in soil and ground water at the Site, 2) a remedial investigation (RI) to define the extent and magnitude of TCE and its degradation products in indoor air at the Site, and 3) Risk evaluations for exposures to both PFAS and TCE (and degradation products) at the Site. In the meantime, the Air Force has been in contact with Lockheed Martin regarding the potential risks of exposure at and near the Site. Likelihood of exposures to community members is low due to restricted access to the site and surrounding area. EPA currently anticipates that there will be sufficient data to make a Human Exposure evaluation by November 2028.