Geochemical and Microbiological Processes that Affect Migration and Natural Attenuation of Chlorinated Solvents in Fractured Sedimentary Rock, Naval Air Warfare Center (NAWC), West Trenton, N.J.
Results of a multichannel analysis of surface waves (MASW) measurement of a subsurface north-south trending cross section across a fault zone at the Naval Air Warfare Center (NAWC
) Research Site in West Trenton, New Jersey. Below is the interpreted geologic section, which shows the fault zone, based on the MASW results (Modified version of Figure 3 from Ivanov and others, 2006
scientists installing diffusion samplers and microcosms (circa 2005) to study subsurface bacteria that degrade trichloroethylene (TCE). The sampling devices were placed in wells at the site and will be recovered one year later. Analysis of sampling data will help USGS
and U.S. Navy scientists evaluate the performance of a biostimulation and bioaugmentation experiment designed to bioremediate contaminants in fractured rock.
The syringes strapped to the sided of the packer pipe rod are for measuring concentrations of dissolved hydrogen gas. USGS
scientists are testing two syringe materials in order to determine which is best suited for long-term diffusion sampling in trichloroethylene-contaminated fractured rock aquifers.
Drilling operations at the NAWC
site (circa 2005). Samples of rock core were collected and were analyzed for concentrations of volatile organic compounds (VOCs) at about 50 various depths, providing a direct measure of the contaminant concentrations in the rock matrix.
The bottom of the 4-inch coring bit (May 2005) used to collect core from land surface to a depth of about 170 feet. One of many uses for the cores was to provide direct information on the geology and hydrogeology of the fractured bedrock at the NAWC
scientists processed cores for later analysis of trichloroethylene (TCE), dichloroethylene (DCE), and vinyl chloride in the cores (circa 2005). A blue tarp was laid on the ground to capture any spills of potentially contaminated materials from the cores.
scientists processing a bedrock core taken from the NAWC
site (circa 2005). The core was sampled near fractures and the rock matrix was analyzed for volatile organic compounds (VOCs).
A closeup of a fracture cutting through a core that was collected from the NAWC
site (circa 2005). Fractures such as this one control the migration of contaminants at the site. Note the rough texture of the surface of the fracture.
To avoid cross contamination during sampling, the drilling and sampling equipment was steam cleaned (circa 2005).
A close-up view of a heat-pulse flow-meter tool. The tool was used to determine the vertical flow-rate of groundwater in boreholes at the site. This information is used to determine the hydraulic properties of fractures during ambient and pumping conditions.
A ribbon NAPL
sample cloth used to detect the presence of separate phase trichloroethylene (DNAPL
) in boreholes (circa 2005). The cloth was stained when pure trichloroethylene and methanol was applied in the lab during a test of the technology.
scientist collecting water samples for chemical analysis and measuring pH, specific conductance, and other field parameters of water pumped from a well (not in photo). The water sample was analyzed for contaminants such as volatile organic compounds (circa 2005).
scientists conducted outcrop studies in 2003 and 2004 to gather information on the pattern of fracturing and its correlation with rock type in the rocks around the site. This information was used to better understand the migration of the trichloroethylene (TCE) plume at the site.
The Lockatong Formation, a cyclically deposited mudstone, is the host rock for the trychloroetylene (TCE) plume at the NAWC
site. The formation is characterized by bedding-controlled fracturing as well as strata bound high-angle jointing.
A view of a mudstone of the Lockatong Formation, showing bedding (dipping gently to the left of the picture), bedding-plane parting fractures, and strata bound vertical jointing (rock face just to the left of the rock hammer). Fractures such as these control the transport of trichloroethylene (TCE) at the NAWC
In 2004, USGS
drillers cored a hole just east of the site to determine the location of a fault that passes through the site, and to better understand its geologic and hydrogeologic properties. The fault zone impedes the flow of groundwater and is a major control on the groundwater flow system at the NAWC
Rock core of the heavily faulted Stockton Formation retrieved from a northeast-trending fault zone. The fault zone passes through the southeast corner of the site, separating the Stockton on the southeast from the Lockatong Formation on the northwest. The fault zone acts as a barrier to trichloroethylene (TCE) migration.
A close-up of the fault-zone core showing open joints perpendicular to bedding in the Stockton Formation sandstone. This core along with others was used to more accurately map the location of the fault zone at the NAWC
site. Fractures in the core yield clues to the 3-dimentional orientation of the fault and its direction of movement.
The Naval Air Warfare Center (NAWC
), West Trenton, N.J., was originally a jet engine testing facility. The site is now used by a multidisciplinary team of scientists to study the fate of trichloroethylene (TCE) in fractured rock.
Jet engine testing equipment at the site was cooled with trichloroethylene (TCE). The NAWC
site is now used by the USGS
and its partners to study the fate of TCE that leaked into fractured rock.
Historical photo of the NAWC
site during construction (circa 1950s). The site is no longer used by the U.S. Navy for jet engine testing.
Aerial view of the Naval Air Warfare Center (NAWC
), West Trenton, N.J., when it was operating. The facility was closed as part of the base closure and realignment (BRAC
View of the area above the plume of trichloroethylene in fractured sedimentary rock. Extensive piping and large conduits associated with jet engine testing were removed to facilitate the remediation of contaminants in fractured bedrock.
Above-ground trichloroethylene (TCE) pipes at the site. TCE was used as a coolant in the jet-engine testing equipment at the site. The pipes were cut during remedial activities.
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