An apparatus and process for obtaining samples of liquid and gas from subsurface soil is provided having filter zone adjacent an external expander ring. The expander ring creates a void within the soil substrate which encourages the accumulation of soil-borne fluids. The fluids migrate along a pressure gradient through a plurality of filters before entering a first chamber. A one-way valve regulates the flow of fluid into a second chamber in further communication with a collection tube through which samples are collected at the surface. A second one-way valve having a reverse flow provides additional communication between the chambers for the pressurized cleaning and back-flushing of the apparatus.
This application relates generally to subsurface sampling devices, and more particularly to an apparatus and process for obtaining liquid and gas samples from subsurface soil. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89R18035 between the U.S. Department of Energy (D.O.E.) and Westinghouse Savannah River Company.