SURFACE GEOPHYSICAL EXPLORATION DEVELOPING NONINVASIVE TOOLS TO MONITOR PAST LEAKS AROUND HANFORD TANK FARMS

Journal Article · Fri Jun 17 00:00:00 EDT 2011 · PRE-PUBLICATION ENVIRONMENTAL MONITORING AND ASSESSMENT SPRINGER

OSTI ID:1017420

DA, MYERS; DF, RUCKER; MT, LEVITT; B, CUBBAGE; GE, NOONAN; M, MCNEILL; C, HENDERSON

A characterization program has been developed at Hanford to image past leaks in and around the underground storage tank facilities. The program is based on electrical resistivity, a geophysical technique that maps the distribution of electrical properties of the subsurface. The method was shown to be immediately successful in open areas devoid of underground metallic infrastructure, due to the large contrast in material properties between the highly saline waste and the dry sandy host environment. The results in these areas, confirmed by a limited number of boreholes, demonstrate a tendency for the lateral extent of the underground waste plume to remain within the approximate footprint of the disposal facility. In infrastructure-rich areas, such as tank farms, the conventional application of electrical resistivity using small point-source surface electrodes initially presented a challenge for the resistivity method. The method was then adapted to directly use the buried infrastructure as electrodes for both transmission of electrical current and measurements of voltage. For example, steel-cased wells that surround the tanks were used as long electrodes, which helped to avoid much of the infrastructure problems. Overcoming the drawbacks of the long electrode method has been the focus of our work over the past seven years. The drawbacks include low vertical resolution and limited lateral coverage. The lateral coverage issue has been improved by supplementing the long electrodes with surface electrodes in areas devoid of infrastructure. The vertical resolution has been increased by developing borehole electrode arrays that can fit within the small-diameter drive casing of a direct push rig. The evolution of the program has led to some exceptional advances in the application of geophysical methods, including logistical deployment of the technology in hazardous areas, development of parallel processing resistivity inversion algorithms, and adapting the processing tools to accommodate electrodes of all shapes and locations. The program is accompanied by a full set of quality assurance procedures that cover the layout of sensors, measurement strategies, and software enhancements while insuring the integrity of stored data. The data have been shown to be useful in identifying previously unknown contaminant sources and defining the footprint of precipitation recharge barriers to retard the movement of existing contamination.

• Research Organization: Hanford Site (HNF), Richland, WA (United States)
• Sponsoring Organization: USDOE Office of Environmental Management (EM)
• DOE Contract Number: DE-AC27-08RV14800
• OSTI ID: 1017420
• Report Number(s): WRPS-50043 Rev 0; TRN: US201113%%499
• Journal Information: PRE-PUBLICATION ENVIRONMENTAL MONITORING AND ASSESSMENT SPRINGER, Journal Name: PRE-PUBLICATION ENVIRONMENTAL MONITORING AND ASSESSMENT SPRINGER
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ALGORITHMS
BOREHOLES
CONTAMINATION
DISTRIBUTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRODES
EXPLORATION
MONITORS
PARALLEL PROCESSING
PLUMES
PRECIPITATION
PROCESSING
QUALITY ASSURANCE
RESOLUTION
SENSORS
STORAGE FACILITIES
TANKS
UNDERGROUND STORAGE
WASTES