Fact Sheet Display

LF044 - Landfill X

Site LF044 (Landfill X) consists of several buried piles of asphalt and concrete and is located next to a field within Grazing Management Unit #2 that was used to graze horses and for heavy equipment training.  Asphalt, concrete, and other construction debris had been stockpiled at the site.  Metals and polycyclic aromatic hydrocarbons (PAHs) have been found in the soil.  These compounds may be a source of potential human health and ecological risk.  The groundwater was not impacted by site activities.

To control access to the property and to protect the vernal pools located near the east side of the training area, the West/Annexes/Basewide Operable Unit Soil Record of Decision selected land use and access restrictions as the final soil remedy.  The Air Force built a fence around the perimeter of the site and posted warning signs.  As part of the remedy, a berm was placed within the fence to prevent the migration of contaminated sediment from the training area into the vernal pools north of the site during rain events.

In 2010, the Defense Energy Support Center began the construction of a new above-ground storage tank (AST) fuel facility within the footprint of the LF044 controlled area.  The placement of the fuel facility in the LF044 area was based on its proximity to an existing AST facility on base, as well as to a new off-base fuel pipeline. The placement also avoided the destruction of vernal pools and other sensitive habitats at the alternative construction locations.

Before the tanks could be built, earth-moving equipment removed vegetation, construction debris, and contaminated soil from the construction area.  Most of the concrete debris was taken to Concrush, a construction material recycling company in Fairfield, CA.  The vegetation, weathered asphalt, contaminated soil and other miscellaneous debris were sent to the Hay Road Landfill in Vacaville, CA.  When this phase of the project was complete, the construction area had been scraped to the point where only native soil was exposed.  Earthmoving operations continued to ensure that the foundations for the ASTs were level and met specified geotechnical standards and soil compaction requirements.  Clean soil was then brought onto the construction site to build the secondary containment walls for the AST enclosures.

Once the AST construction project was completed in 2012, the land use and access restrictions were removed from the area within the AST facility footprint.  The AST facility bisects the Site LF044 restricted area, leaving the restrictions on two small areas north of the AST facility and one larger area south of the AST facility.  Additional soil sampling is planned for 2017 to evaluate whether the concentrations of any PAH- and metals-contaminated sediment are low enough in these two northern areas to remove the land use controls (LUCs) from them.  This field activity will not impact the restrictions on the larger southern area.  Adherence to LUCs is evaluated annually.