However, shallow ground-water supplies are generally young (recently recharged) and, because there has been a wide variety of man-made pollutants produced in the 20th century, are more susceptible to contamination than deeper ground water.Information about ground-water age can be used to determine recharge rates and refine hydrologic models of ground-water systems (Reilly and others, 1994; Szabo and others, 1996) and thus to predict the contamination potential and estimate the time needed to flush contaminants through a ground-water system.Young ground water in shallow ground-water systems Young ground water is typically found at depths from 0 to 100 feet in unconsolidated sediments and at depths up to 1000 feet in fractured-rock systems.
Dating to relating a to z
These include (1) uncertainty of the temperature at the water table during recharge, (2) entrapment of excess air during recharge, (3) uncertainty in recharge elevation, (4) thickness of the unsaturated zone, (5) effect of urban air where CFC values may exceed regional values, (6) contamination from a specific local source, (7) microbial degradation (in anaerobic environments), (8) sorption onto organic and mineral surfaces, and (9) mixing of younger and older water in a well. A., 1998, Chemistry of unsaturated zone gases sampled in open boreholes at the crest of Yucca Mountain, Nevada: Data and basic concepts of chemical and physical processes in the mountain: Water Resources Research, v. For additional information, see or contact: Niel Plummer (email: [email protected]) U.
Because of the effect of these factors on CFC concentration, collection of additional data is often needed to determine the apparent age of ground water.
The unexplained shift in paranormal attention towards men visiting Z Ward follows ...
Fts Z is a tubulin homologue and the primary protein of the bacterial Z ring that guides cell division.
Girl Guides plans to stop selling biscuits next year, their national board announced on Saturday.