ArticleCS - Article View

Environmental Projects

This site is under development and updates will be provided.


Comprehensive Response into Intermittent Sheens

Since 1942, Travis Air Force Base has played a significant role in our nation’s defense. During that time, countless military aircraft have taken off, landed, and been refueled; their missions supported by miles of aviation fuel pipelines and aviation fuel tanks. Some of these pipelines are adjacent to the base’s stormwater system, which discharges into Union Creek.  Union Creek is a seasonal creek that consists primarily of treated water that is discharged from the base’s groundwater treatment plant into a drainage ditch, and during the rainy season, Union Creek also serves as a conduit for stormwater.  No drinking water is obtained from Union Creek.

Travis AFB is undertaking a project to investigate and address the intermittent sheens that have appeared on-base along the stormwater drainage ditch area of Union Creek. Sheens may be iridescent or “rainbow” in appearance on the water’s surface. Sheens can be caused by a number of things including petroleum products interacting with the water as well as naturally occurring environmental events, such as the decomposition of plants. Analysis has indicated that a portion of the observed sheens contained varying jet fuels used historically at Travis AFB. These fuels are JP-4, JP-8, and Jet A.

Working closely with the Air Force Civil Engineer Center (AFCEC), the Air Force Petroleum Agency (AFPET), and the Defense Logistics Agency (DLA), Travis AFB has engaged in an aggressive effort to monitor for any fuel sheens and contain any found, investigate potential sources, and remediate impacted areas as needed. In addition to teaming with Air Force and Department of Defense partners, Travis AFB initiated a robust and cooperative process with the EPA, the California State and Regional Water Boards, and other federal, state, and local regulatory agencies, involving bi-weekly meetings, weekly written updates, and on-site visits.  This process has enabled meaningful collaboration, including agency feedback and comments for ongoing efforts.  Travis AFB and its DoD Partners are committed to the success of this project and will continue to work hard to facilitate comprehensive and thorough investigation and response actions.



Containment, Monitoring, & Sampling

An underflow dam construction along the stormwater drainage ditch area of Union Creek. Travis AFB has taken a number of precautionary measures to contain these intermittent sheens, prevent fuel sheen migration, and protect the environment. These measures include, but are not limited to, the strategic placement of booms, absorbent pads, and skimmers along the area of the creek where the intermittent sheens have been observed. Booms are used to contain any sheens which are then absorbed by the pads or skimmers. The effectiveness of these measures is frequently evaluated by Travis AFB personnel and the government contractors who help to maintain them. In addition to these measures, Travis AFB personnel constructed an earthen underflow dam in February 2023, which is designed to contain any sheens so that they may be safely removed.






Monitoring activities along the creek occur frequently with Travis AFB personnel and government contractors performing visual inspections. If a sheen is observed, personnel conduct initial testing to determine whether any petroleum-type product is present. Multiple evaluations are made using testing materials such as Total Petroleum Hydrocarbon (TPH) Strips and Petroleum Absorbing Powder. When circumstances allow, observed sheens are photographed and sampled. In addition to visual monitoring, samples are taken regularly by government contractors as part of a methodical sampling plan as well as in response to any observed sheens.

Investigation & Response

The Travis Team has been engaged in a comprehensive, multi-pronged investigation to identify potential sheen sources by conducting sampling and testing of soil, soil vapor, groundwater, and surface water. This data-driven approach includes a robust sampling effort to collect data as part of the ongoing investigation regarding any contamination in nearby areas. This sampling has been undertaken in a number of phases, methodically testing precise sectors of the base to be better able to identify particular areas of interest and the specific petroleum products present.

This effort also includes assessment of the base’s underground stormwater conveyance system.  Since intermittent sheens have been observed near the flight line stormwater discharge point, known as “Outfall IV,” Travis AFB and the U.S. Army Corps of Engineers (USACE) used technological assets, including remote video surveillance, to evaluate targeted segments of the underground conveyance system. During this process, the team observed cracks and fractures along the conveyance system. Travis AFB and the USACE are working to clean and repair this system This effort is a key step to prevent any fuel product infiltration into the system. 

Project Areas


1. Stormwater System Repairs. Travis AFB continues to work with the USACE’s Rapid Response Team to address identified defects in the base’s stormwater system. This work aims to expeditiously repair cracks and fractures in the aged system’s infrastructure. In January 2024, the USACE team completed Stormwater Conveyance System cleaning efforts to flush out the pipeline of any possible contaminants residing in the line and utilized video scoping, conducted in 2023, to examine the length of the conveyance. The USACE team identified numerous cracks and fractures along the conveyance.  

Travis AFB anticipates initiating work during the Summer 2024 to line approximately 2,400 linear feet of the Stormwater Conveyance System pipe between two drop inlets (i.e., manholes) traversing the runway. The liner will consist of a 3-ply laminate, which combines two layers of polyethylene and high strength cord gridTravis AFB closely collaborated with the Regional Water Board to ensure the water used during the curing process is tested before release to ensure it is not harmful to human health or the environment 

2. Source Investigation and Response. Travis AFB and its contractors have already been successful in removing 3,000 cubic yards of soil on base that may have been contaminated from jet fuel and replaced it with clean fill. 

3. Fuel Transfer Pipeline Closure. Travis AFB is currently developing plans to start the closure process for fuel pipelines that are no longer used at the installation. These older pipelines are often referred to as legacy fuel pipelines. This pipeline closure project involves several Department of Defense partners: the Defense Logistics Agency, the Air Force Petroleum Agency, and the U.S. Army Corps of Engineers. These agencies are the nation’s fuels experts, and they have significant experience in decommissioning legacy fuel lines. The closure of legacy fuel lines will proceed in three main phases: 1) Pipeline defueling and cleaning; 2) Subsurface sampling along pipelines; 3) Remediation and restoration, as needed. 

Restoration Schedule

Next Restoration Advisory Board Meeting: The next RAB meeting is scheduled for April 18, 2024, 7 p.m. - 8:30 p.m. at the Northern Solano County Association of Realtors office; 3690 Hilborn Road Fairfield, CA 94534. Immediately following the RAB, there will be a Union Creek update.

For more information please contact the Travis Restoration Program Manager at or phone 707-424-2812.