Helium: Samples are collected in special copper tubes fitted with stainless steel pinch-off clamps. F., 1988, Hydrogeologic Framework of the Virginia Coastal Plain: U. The discharge end of the tubes is fitted with an overpressure valve to prevent gas bubble formation in the ground-water sample Samples are collected in coated-glass bottles fitted with Teflon septum.
This system represents a capability for characterizing groundwater recharge conditions by dissolved gas analysis that is unmatched by any other laboratory. Once formed, tritium is quickly incorporated into water molecules and resides in the lower stratosphere for 1–10 years.1) to determine the CFC-modeled recharge date, which equates to the time that the water was isolated from the atmosphere in the unsaturated zone. C., 1983, Development of reaction models for ground-water systems: Geochimica et Cosmochimica Acta, v. H) is the radioactive isotope of hydrogen; it has a half-life of 12.43 years (International Atomic Energy Agency, 1981) and is an excellent indicator of ground water recharged since 1952 (Clark and Fritz, 1997). Time and cost considerations prohibit a detailed assessment of each of the more than 4,000 public water supplies in Virginia.
Thus the VAS study proposes to characterize the susceptibility of all of the regional aquifers by studying a representative sample of water-supply wells.
The T/3He ages were calculated for groundwater samples collected from the locations Wannsee and Lieper Bucht area, southwestern Berlin, Germany.
The calculated ages were used to study the infiltration of lake water into the groundwater system.
Actual sample volume is dependent upon the p H and alkalinity of the water. M., 1998, Ground water and surface water, a single resource: U.
CFCs are stable synthetic organic compounds that were first manufactured in the 1930s for use as refrigerants, aerosol propellants, cleaning agents, solvents, and blowing agents in the production of foam rubber and plastics (Busenberg and Plummer, 1992).
Susceptibility designations will be assigned to the regional aquifers based on statistical and geospatial analysis of the age determinations from samples collected as part of this study and previous studies by the U. Ground-water apparent age provides information about the flow of water within an aquifer and the susceptibility of a water supply to near-surface contamination. Environmental Protection Agency is charged with implementing the Amendments and has mandated that each state must develop a SWAP to identify source areas of public drinking water, assess the susceptibility of public supplies to contamination, and make this information available to citizens. M., 1985, Availability and quality of ground water in the Piedmont province of Virginia: U. Geological Survey Water Resources Investigations Report 85-4235, 33 p.