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1	Chlorofluorocarbons as Hydrologic Tracers, A New Technology Randall, J. H., Schultz, T. R. 01 May 1976 (has links) From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona / The nationwide research undertaken to study environmentally dispersed chlorofluorocarbons introduced into the atmosphere from aerosol cans and refrigeration systems has indicated that these compounds are potentially ideal hydrologic tracers, especially Freon-11 (Cl₃CF). The major advantages of Cl₃CF as a tracer are its non-polluting conservative nature, extremely low toxicity and sorptivity on clays, quantifiable build-up in the atmosphere, and a detection limit of about 10⁻¹⁴ grams. Quick and inexpensive detection of Cl₃CF can be done using a field-operable gas chromatograph with a pulsed electron-capture detector system. The presence of Cl₃CF in ground water, indicating an age of less than 30 years, will permit delineation of recent recharge areas. The absolute age of the recharging water is proportional to the atmospheric concentration of Cl₃CF at the time of recharge. The simple quantifiable increase of Cl₃CF in the atmosphere should therefore yield more accurate ages than those determined by tritium analysis. Hydrology -- Arizona. Water resources development -- Arizona. Hydrology -- Southwestern states. Gas chromatography Tracers Chlorofluorocarbon Air pollution Atmosphere Pollutant identification Dating water
2	The Use of Chemical Hydrographs in Groundwater Quality Studies Schmidt, Kenneth D. 23 April 1971 (has links) From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / High nitrates in drinking water are significant in relation to an infant disease, methemoglobinemia, and the U.S. public health service has set a limit of 45 ppm for human consumption. This paper illustrates how chemical hydrographs were used in a study of nitrates in the groundwater of the Fresno-Clovis metropolitan area (F.C.M.A.) of semiarid central California. The area comprises about 145 square miles, with a population of 310,000. Urban water use is entirely derived from wells, whereas the surrounding agriculture relies on surface and ground water. In 1965, the California department of water resources noted nitrate concentrations in the F.C.M.A. were exceeding the safe limit. A number of sources of error in chemical analyses of water quality are noted. A measure of the accuracies of analyses and a method of double-checking anomalous results is furnished by plotting chemical hydrographs of individual wells. Seasonal changes in nitrate were consistent for many parts of the area, and were related to hydrogeologic factors and parameters directly affecting nitrification. Nitrate hydrographs were monitored by chloride hydrographs. The highest nitrate concentrations were in the shallower parts of the aquifer, and well deepening and changes in water level, pumping patterns and recharge rates complicated interpretations. However, the hydrographs helped to pinpoint the source of nitrate in areas where several possible sources were present. Water resources development -- Arizona. Hydrology -- Arizona. Hydrology -- Southwestern states. Nitrates Hydrographs Groundwater Chemical analysis Water chemistry California Semiarid climates Chlorides Seasonal Hydrogeology Water quality control Sewage lagoons Pollutant identification Hydrograph analysis Water wells Water pollution sources Chemical hydrographs
3	Water Quality of Runoff from Surface Mined Lands in Northern Arizona Kempf, J., Leonhart, L., Fogel, M., Duckstein, L. 15 April 1978 (has links) From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Surface mining of coal in the western U.S. can cause problems of increased salinity and heavy metal contamination in runoff along with a lack of enough rainfall to sustain plant growth for reclamation. To facilitate the planning of reclamation efforts in such areas results are described of a water quality sampling experiment on the ponds and runoff at the University of Arizona Experimental Watershed on Black Mesa in northern Arizona. A systems theoretic framework is employed to model the watershed and the results of a computer simulation based on this model is used to indicate that salinity buildup could be expected over time, given a minimal change in watershed configuration, with possible development of fluoride contamination being of particular concern. Water quality tests of the pond water and runoff on Black Mesa indicated that the water is within Federal standards for drinking and irrigation, except for sodium and fluoride. It is suggested that if it is economically desirable, the collection of more data on the ponds could be used to develop a simulation model of pond subsystems along the lines of the methodology outlined in this analysis. Hydrology -- Arizona. Water resources development -- Arizona. Hydrology -- Southwestern states. Water quality Runoff Ponds Coal mines Environmental effects Strip mine wastes Water pollution sources Surface runoff Mine water Pollutant identification Salinity Heavy metals Fluorides Sodium Land reclamation Planning Watershed management Computer models Systems analysis Model studies Arizona Black Mesa

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