Workshop and Field Trip on Characterization of Contamination in Fracture Rock

U.S. Geological Survey scientists and their colleagues are leading a workshop and a field trip for the 2007 NGWA/U.S. EPA Fractured Rock Conference: State of the Science and Measuring Success in Remediation, Portland, Maine, September 24-27, 2007. The NGWA (National Ground Water Association) and the U.S. EPA (U.S. Environmental Protection Agency) are hosting the conference. Several USGS scientists are presenting papers at the conference two of which were special guest speakers. USGS scientists are also on the conference's advisory council.

Workshop on Fate, Transport, and Remediation of Chlorinated Solvents in Fractured Sedimentary Rocks at the Former Naval Air Warfare Center, West Trenton, New Jersey

Workshop Flyer (pdf)

The workshop will present results of multidisciplinary investigations conducted by the U.S. Geological Survey, in cooperation with the U.S. Navy's Naval Facilities Engineering Command, GeoSyntec Consultants, and ECOR Solutions, Inc. of trichloroethene (TCE) distribution, transport, and biodegradation in fractured mudstones underlying the former Naval Air Warfare Center (NAWC), West Trenton, NJ. Beginning in the 1950Õs, TCE was released to land surface in dissolved and pure phases, and has been observed in ground water as deep as 60 m. Natural microbial reductive dechlorination has partially transformed TCE to cis-1,2-dichloroethene (cDCE), vinyl chloride (VC), and ethene. A pump and treat system has operated for about a decade, but dissolved contaminant concentrations remain high (up to ~140 milligrams per liter (mg/L) TCE, ~20 mg/L cDCE, and ~4 mg/L VC), suggesting that substantial contaminant mass remains in low-permeability rock. A bioaugmentation pilot study was conducted to investigate enhanced biodegradation of TCE and its daughter products.

Oral and poster presentations, computer displays, rock core, and field equipment will be used to illustrate methods, results, and interpretation of field investigations at NAWC. Presentations will focus on three themes:

• Finding Flow and Transport Paths – Results of hydraulic and tracer tests and geologic and geophysical characterization have been used together with flow modeling to identify paths of fluid and chemical movement.
• Monitoring Contaminants, Geochemistry, and Microbiology – Innovative approaches to monitoring contaminant concentrations, water chemistry, and redox conditions have shown significant spatial variability of these constituents, reflecting the highly heterogeneous geologic and geochemical environment. This variability is a critical factor in designing remediation strategies.
• Evaluating Remediation Effectiveness – Pump and treat has been relatively inefficient, in terms of contaminant mass removed per volume pumped. Bioaugmentation shows promise for increasing natural degradation rates and enabling complete transformation of TCE. Reactive transport modeling that synthesizes multidisciplinary subsurface data is being used to compare remediation strategies.

The workshop will be held on Wednesday, September 26, 2007, from 10:20 a.m. to 3:00 p.m. The instructors for the workshop are Claire R. Tiedeman, Daniel J. Goode, Pierre J. Lacombe, Paul M. Bradley, William C. Burton, Francis H. Chapelle, Gary P. Curtis, Karl J. Ellefsen, Thomas E. Imbrigiotta, Carole D. Johnson, Kinga M. Revesz, Marjorie S. Schulz, Allen M. Shapiro, Ph.D., and John H. Williams, USGS; Mary F. De Flaun, GeoSyntec Consultants; and Paul A. Hsieh, USGS.

Field Trip: Borehole Geophysics Demonstration for Fractured Rock Characterization

The postconference field trip—"Borehole Geophysics Demonstration for Fractured Rock Characterization," September 27—will include demonstrations of discrete-interval monitoring, borehole imaging, flowmeter, and fluid-property logging in fractured rock. Real-time data will be collected during the field trip, and detailed instruction will be given on the analysis of the data with particular focus on fractured rock aquifers at the demonstration site. The leaders of the field trip are John Williams, USGS; Carole Johnson, USGS; Fred Paillet, University of Maine (retired USGS), James Lococo, James Lococo, Mount Sopris Instruments; and Thomas Ballestero, University of New Hampshire.

General Conference Information

• Flyer on the Workshop on Fate, Transport, and Remediation of Chlorinated Solvents in Fractured Sedimentary Rocks at the Former Naval Air Warfare Center, West Trenton, New Jersey (pdf)

Guest Speakers From the USGS

Special guest speakers from the USGS for this conference include:

• Progress Has Been Made in Characterizing Fractured Rock Aquifers, but What Are the Implications for Remediation?, by Allen Shapiro (USGS)
• Effect of depth and geochemical conditions on distribution of uranium and radium in ground water in fractured bedrock, central New Jersey, by Zoltan Szabo (USGS)

Presentations with USGS Authors

• Change in biogeochemistry and chloroethene degradation potential with depth in a fractured bedrock borehole at Naval Air Warfare Center, Trenton New Jersey, by Paul M. Bradley (USGS), and Francis H. Chapelle (USGS)
• Case History: Remediation of fractured bedrock aquifer containing TCE DNAPL, by Jeffrey P. Orient (Tetra Tech NUS ), Lonnie Monaco (Navy BRAC Program Management Northeast), Ronald A. Sloto (USGS), Kathryn L. Davies (U.S. EPA, Region III)
• Comparison of alternative numerical models to represent permeability anisotropy in fractured-sedimentary rock, by Richard M. Yager (USGS)
• Comparison of stair-step and dipping-layer approaches for simulation of flow and advective transport in fractured-sedimentary formations, by Daniel J. Goode (USGS), and Ying Fan (Rutgers University)
• Hydraulic gradients in recharge and discharge areas and apparent ground water age dates from the characterization of multiple Regolith-Fractured Bedrock Ground Water Research Stations in North Carolina, by Melinda Chapman (USGS), Melissa Schlegel (USGS), Brad A. Huffman (USGS), and Kristen B. McSwain (USGS)

USGS Information on Fractured Rock

• Chlorinated Solvents in Fractured Sedimentary Rock, Naval Air Warfare Center (NAWC) Research Site, West Trenton, New Jersey
• Transport Phenomena in Fractured Rock Research
• Hydrology of Fractured Rocks Research
• Multidisciplinary Characterization of Fluid Flow and Solute Transport in Fractured Rock, Mirror Lake, New Hampshire
• Branch of Geophysics Research with the Toxic Substances Hydrology Program

Related Headlines

• USGS Patents the Multifunction Bedrock-Aquifer Transportable Testing Tool (BAT3)
• USGS Develops Geophysical Methods to Improve Remediation Monitoring and Site Characterization
• New Paradigm for Fractured Rock Cleanup
• What Controls the Migration of Chlorinated Solvents in Fractured Rock?

Back to Meetings Page