Characterizing and Monitoring Contaminants at a Complex Fractured Rock Site

Battelle has been working with the U.S. Navy for more than 15 years to characterize, treat and monitor groundwater at the former Naval Air Warfare Center (NAWC) Warminster. Groundwater in fractured rock beneath the site is contaminated with chlorinated volatile organic compounds (CVOCs) from historic activities at the site. Testing determined that groundwater concentrations were above maximum contaminant levels set by the EPA. Because groundwater from the site is a source of drinking water for surrounding communities, finding solutions is a high priority for the Navy. The Navy needed to fully characterize the CVOC plume and optimize the treatment and long-term monitoring (LTM) strategies associated with plume remediation.  

Battelle implemented a passive groundwater sampling approach and optimized the monitoring well sampling network to significantly reduce LTM costs. High-resolution site characterization was used to provide better insights into vertical CVOC distribution and groundwater flow conditions in the fractured bedrock source area. Characterization activities included vertical chemical concentration profiling, collection and field screening of source area rock core samples. Researchers also used borehole geophysics along with vertical borehole flow measurements and identification of water-bearing zones using a heat-pulse flowmeter. Data from field samples was used in combination with bench-scale testing to inform development of an in-situ chemical oxidation (ISCO) implementation strategy for remediation of the plume. 

Implementation of the passive sampling and LTM optimization for the COV plume resulted in annual savings of more that $100k for the Navy’s LTM program at the site.