An aerial photograph of the former Naval Air Warfare Center, West Trenton, New Jersey, showing the major (red, on the left) and minor (yellow, on the right) trichloroethylene (TCE) contamination plumes and the location of active pump-and-treat recovery wells (gold circles). USGS scientists found that natural attenuation accelerates pump-and-treat cleanup of TCE in fractured rock. Photo credit: U.S. Navy.
USGS scientist collecting water-level data from an observation well during an aquifer test at the Naval Air Warfare Center Fractured Rock Research Site, West Trenton, New Jersey. The test involved a new method where just one well from the site's active pump-and-treat remediation system is shut down.
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).
USGS 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 site.
USGS 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.
USGS 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.