Fifth five year review announcement
Purpose - to make sure that selected cleanup actions effectively protect human health and the environment.
Community members who have questions about the site or the Five-Year Review process, or who would like to participate in a community interview, are asked to contact:
Ross Davis, State Project Manager
Colorado Department of Public Health and Environment
4300 Cherry Creek Drive South
Denver, CO 80246-1530
Armando Saenz, Remedial Project Manager
U.S. EPA Region 8 (EPR-SR)
1595 Wynkoop Street
Denver, CO 80202-1129
- 4661 Monaco St., Denver.
- Covers five square miles in Adams County.
- The site was first developed in 1962 and was used for the storage and repackaging of bulk chemicals from rail cars and drums.
- In 1981 a random sample of municipal drinking water identified organic chemicals in groundwater and this site was determined to be the main source of the contamination.
- The identified plume of groundwater contamination extends from north of Sand creek to Quebec Street on the east, Holly Street on the west and East 86th Avenue on the north.
- The site was placed on the list of Superfund sites in August 1990.
- Tetrachloroethylene (PCE), trichloroethylene (TCE), 1,1-dichloroethane (1,1-DCA), 1,1-dichloroethene (1,1-DCE) and vinyl chloride.
- Long-term, chronic exposure to the contaminants is the major health risk to residents of the area from:
- Ingestion of contaminated groundwater.
- Skin exposure to contaminated water
- Inhalation of vapors from groundwater.
- Most area residents receive drinking water from the municipal drinking water supply that has been treated to remove the contaminants.
- Residents who use shallow (less than 100 feet) groundwater from residential wells for domestic purposes may be receiving contaminated water.
- Surface soil, air and surface water do not pose a significant health threat.
- EPA began the conversion of about 400 residences from private shallow wells to municipal water in 1985.
- The Klein Water Treatment Plant, which treats all South Adams County Water Supply District water, was completed in 1989.
- EPA removed leaking and corroded drums in 1989.
- Cleanup activities included:
- Treating contaminated soils through soil vapor extraction.
- Treating contaminated groundwater through air sparging and soil vapor extraction.
- Using groundwater extraction wells to prevent further migration of contamination.
- Construction of the soil vapor extraction system and air sparging system was completed in 1999.
- Since the treatment systems became operational, monitoring wells have shown a downward trend in contaminant concentrations.
- To save on costs, we have taken over the everyday operations at the plant site and continue running the treatment system.