Abstract: This technique for detecting underground contamination by organic fluids employs a plurality of spaced-apart boreholes adjacent a region to be tested for contamination. A neutron backscatter gauge is introduced into each of the boreholes for measuring the concentration of hydrogen in the soil surrounding the borehole. Such measurements are made at a plurality of spaced elevations along such a borehole and the distribution of hydrogen concentration as a function of elevation is compared with the expected distribution of hydrogen from underground sources of hydrogen, for distinguishing organic fluid contamination from other sources of hydrogen. For example, one can distinguish buried concrete or underground water from organic contamination. Measurements can also be made using chemical analysis methods. In another embodiment, the invention is used to profile and affect biodegradation. A plurality of spaced apart boreholes are provided in the buried material (for example, dump site).

Abstract: Soil contaminated with contaminants such as a heavy hydrocarbon or a chlorinated hydrocarbon is cleaned, preferably on-site, by contacting the contaminated soil with a supersurfactant such as the micellar surfactant formed by sonicating polar substituted heavy hydrocarbon in the presence of an alkali metal salt such as sodium silicate and a free radical generating agent such as hydrogen peroxide and sonicating the suspension. At least 85% of the contaminant is flushed or washed from the soil including fine particles having a particle size below about 70 microns.

Abstract: A vadose zone monitoring system for detecting leaks from a contaminant storage facility or the like is disclosed in which leaks are detected in a confined radial area around at least one generally horizontal, neutron access tube disposed under the landfill. A wicking layer of material increases the leakage detection coverage area by laterally transmitting leakage to the access tube via capillary action. A clay liner may be disposed between the landfill and wicking layer for controlling the rate of leakage to prevent build-up of a pressure head large enough to force liquid through the wicking layer before it is conducted laterally to the access tube. Leak detection may be carried out by neutron moderation techniques or other moisture detection schemes for developing logs indicative of the leakage from the landfill. The wicking layer permits an entire network of access tubes or other leak detection means to be installed under substantially the entire landfill for monitoring leaks therefrom.