Monitoring Perched Ground Water in the Vadose Zone

• Main Authors: Wilson, L. G., Schmidt, K. D.
• Other Authors: Water Resources Research Center
• Language: en_US
• Published: American Water Resources Association (Minneapolis, MN) 1978
• Subjects: perched ground water; vadose zone; water quality monitoring; sampling procedures; irrigation return flow
• Online Access: http://hdl.handle.net/10150/305294

American Water Resources Association Symposium Proceedings / Reprinted from Establishment of Water Quality Monitoring Programs / Edited By: Lorne G. Everett and Kenneth D. Schmidt / June 12-14, 1978 / San Francisco, California === Traditional techniques for monitoring the mass flux of pollutants in the vadose zone involve obtaining point samples of solute, either by core sampling of solids, followed by laboratory extraction, or by installation of suction probes. An alternative sampling technique, discussed in this paper, is to sample perched ground water within the vadose zone. Large amounts of water may be pumped for sampling purposes from wells drilled into productive, perched ground -water bodies. Alternatively, cascading water from perched regions may be sampled in wells with perforations above the water table. Analytical results of samples from such wells are more representative of regional conditions than small point samples. Case studies are presented on sampling from perched ground water underlying a point source (an oxidation pond), a line source (an ephemeral stream), and a diffuse source (irrigation return flow).