Travis AFB Sustainability Study Report Final Background Report | Page 132
Subarea LF007C: A general landfill that used trench and cover
methods from approximately 1950 through 1970. Historical practices
resulted in groundwater contamination with chlorinated VOCs,
dioxins, and polychlorinated biphenyls (PCBs). 1.6 acres of the plume
extends off‐base.
Findings
Three sites with contaminated groundwater extend off‐base.
Travis AFB maintains an easement for these areas and is currently
conducting cleanup of this contamination.
Site SS030: Mostly undeveloped land near the southern base
boundary. Historical practices associated with Building 1125 are
believed to have resulted in groundwater contamination with
chlorinated VOCs. 91.6 acres of the plume extend off‐base.
Air quality attainment
ISSUE
Travis AFB is within a region that is not in attainment for
MINOR‐11
PM2.5 and Ozone.
To carry out the necessary cleanup activities on private property, Travis AFB
purchased access and environmental response easements from the
landowners. These easements contain legal restrictions that prevent
landowners from engaging in water development or soil disturbing activities
that could interfere with cleanup activities. Cleanup activities involving
extracting, treating, and discharging the groundwater began in 1998 and still
take place today. At the other contaminated sites on‐base, the cleanup
actions and monitoring have minimized the migration of contaminated
groundwater, preventing any additional off‐base migration.
Compatibility Assessment
In California, the California Air Resources Board has established CAAQS in
addition to the federal standards established under the Clean Air Act. Areas
are classified as either in attainment or nonattainment under both federal
and state standards.
California is divided into 15 air basins, based on the topography of the state.
Solano County is split between two air basins. The eastern side of
Solano County is within the Sacramento Valley Air Basin and the western
side is within the San Francisco Bay Area Air Basin. Travis AFB is located
within the San Francisco Bay Area Air Basin and falls under the jurisdiction of
the Bay Area Air Quality Management District (BAAQMD).
Each month, over four million gallons of groundwater are extracted from
contaminated groundwater plumes under Travis AFB, treated on‐base, and
discharged to Union Creek. This treated groundwater, which meets strict
clean water standards, supplements the flow of the eastern branch of
Union Creek. After more than a decade of cleanup activities, the
contaminant levels are much lower than their initial values but are still high
enough to require additional clean up action.
To estimate the sources and quantities of pollution, the California Air
Resources Board maintains an inventory of California emission trends
through on‐going monitoring. The San Francisco Bay Area Air Basin contains
20 air monitoring stations. The closest station to Travis AFB is the Fairfield
station, which is located on Chadbourne Road and monitors ozone levels.
The Vallejo monitoring station on Tuolumne Street, the next closest station
to Travis AFB, monitors Carbon Monoxide, Nitrogen Dioxide, Sulfur Dioxide,
Source: Final Proposed Plan for Groundwater Cleanup, Final Travis AFB Groundwater
Record of Decision
Page 5‐12
Compatibility Assessment