Idaho National Engineering Laboratory
Description
The Rapid Geophysical Surveyor (RGS) is a passive, nonintrusive geophysical measurement system. This automated system collects high-resolution geophysical data required for economical, accurate buried waste site characterization. The measurement system is based on a magnetometer sensor that can detect anomalies in the subsurface magnetic fields and quantitatively measure natural magnetic fields of buried ferromagnetic waste components.
The RGS system is a hand pushed, nonferrous vehicle that consists of magnetic sensors, a data logger, data storage hardware, and menu-driven software. The user is required to push a 20-lb cart to collect magnetic data. Magnetic data are automatically collected and stored at user-specified intervals as close as 2-in. apart along survey profile lines. These data form a high-resolution database capable of locating individual objects and potentially determining object orientation, shape, and depth to burial. There is no input required for this passive system, and the output of the RGS is a set of spatially correlated magnetic data. Currently, RGS is limited to sites that are fairly flat with little or no vegetation.
Technical Performance
Field Demonstration. The RGS was field demonstrated in September 1992 and functioned as designed. The magnetometers are sealed by the manufacturer and required no further calibration; however, the distance wheel was calibrated during operations. The RGS collected magnetic data at a maximum rate of 25,000 data points per hour. This is 30 to 300 times faster than the baseline, hand-held magnetometer technologies. The RGS operates on 2 12-volt gel cell batteries and draws about 1/2 watt continuous power. The cost of using the RGS on a waste site is proportional to the size of the site and man-hours required to perform a survey. Maintenance costs are unknown but are expected to be minimal. The complete prototype system cost is under $200K.
Projected Performance
It is estimated that a robust positioning system could be incorporated onto the RGS by FY94. This may enable the application of RGS to buried waste sites that are not flat and smooth. The major technical challenges are associated with the effective processing and presentation of large amounts of geophysical data and with interpreting the results of the data processing such that the correlation between data and buried objects is achieved.
Waste Applicability
This technique is applicable to buried waste in a soil medium where the buried waste has a ferrous content or where nonferrous waste is enclosed in a ferrous container.
Status
The prototype system is available now. A robust positioning system could be available by FY94.
Regulatory Considerations
Regulatory issues are expected to be minimal. Because this is a nonintrusive characterization technique, there is no subsurface disturbance or process waste, and little or no decontamination of equipment is anticipated by using RGS. There are no health hazards originating from the RGS itself; however, exposure to hazardous materials is possible directly from survey sites.
Potential Commercial Applications
Commercial applications include underground utility detection (although the cost and level of detail may be impractical), and geotechnical mining applications (especially where mineralized veins carry ferrous components).
Baseline Technology
Hand-held instrumentation represents the current method for collecting magnetic and electromagnetic geophysical data. A hand-positioned magnetometer system is labor intensive to use. In contrast, the RGS can perform geophysical magnetic surveys more quickly (30 to 300 times faster) and more economically ($.25 versus $5 per data point) than can hand-held instruments. Also, because the RGS is an automated system, it can collect spatially denser data sets than previously thought possible, thereby providing a high-resolution picture of the state of the buried waste site.
Intellectual Property Rights
A patent disclosure has been made.
For more information,please contact:
References
Go to the Characterization and Monitoring Technology Profiles Index