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Management of Artificial Recharge Wells for Groundwater Quality ControlWilson, L. G. 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 / Recharge wells may be used in various problems relating to chemical water quality because of the phenomenon of in-aquifer mixing. This paper reviews specific recharge well-mixing techniques of possible utility in underground mixing operations for nitrate control. Illustrative data from field studies at a recharge site near Tucson, Arizona are presented. Both single- and 2-well types of mixing were investigated. In single-well operations, effluent recharge and pumping of the subsequent mixture occur at the same well. Differences in chlorine ion levels were used to distinguish between recharge effluent and native groundwater. Undiluted effluent was discharged in single-well operations until a pumped volume ratio of about 0.4 was attained. Dilution increased steadily with increased pumping and the relative concentration versus pumped volume curve was s-shaped. Seven-day pauses after effluent recharge resulted in immediate pumping of almost completely diluted water, probably because groundwater movement swept the effluent beyond the pumping unit during the pause. With 2-well pumping, the chlorine breakthrough curve reached a constant level at about 13 days and was close to that of the pause-type, single-well regime.
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Renovating Sewage Effluent by Ground-Water RechargeBouwer, Herman, Lance, J. C., Rice, R. C. 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 / Sewage effluent is commonly used for the irrigation of crops that are not consumed raw. Due to continued population growth in the Salt River Valley, Arizona, economic reuse of municipal waste waters is becoming essential. The salt river bed has about 3 ft of fine loamy sand underlain by sand and gravel layers to great depth and a groundwater table at about 10 ft depth. These conditions are very favorable for high-rate waste water reclamation by groundwater recharge. The activated sludge plant in phoenix will probably be discharging 250 mgd by the year 2000. At 4.5 ft average annual water use, this could irrigate about 70,000 acres, possibly more than agriculture will need at that time. A sewage effluent renovation pilot project was located about 1.5 miles from the plant. It contains 6 parallel recharge basins 20 to 700 ft each, spaced 20 ft apart. The basins were covered by grass, gravel or were left bare. Observation wells were installed at various locations in the area. Results indicated that infiltration rates were fastest in the grassy basins. Phosphate, nitrogen and median fecal coliform levels were all lower after this form of tertiary treatment. Practical details of the application of this water reclamation method in the Salt River Valley are outlined. Costs would be 5 dollars/af, less than 1/10 the equivalent costs of in-plant tertiary treatments.
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Effect of a Grass and Soil Filter on Tucson Urban Runoff: A Preliminary EvaluationPopkin, Barney Paul 06 May 1972 (has links)
From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / Storm runoff from the Tucson metropolitan area is unsuitable for most uses without processing. A lysimeter comprised of a grass and soil filter was constructed and is being evaluated as a water-quality treatment facility. The lysimeter is 200 feet long, 4 feet wide and 5 feet deep, and contains homogeneous calcareous loam covered by common grasses. Experimental apparatus was installed to divert less than a cubic foot per second of runoff from urbanized Arcadia Watershed. Runoff flows by gravity over the lysimeter, where surface inflow, surface outflow and subsurface outflow are measured and sampled. Four trials, each associated with a discrete runoff event, were conducted in the fall of 1971. Water samples were analyzed for inorganic chemical constituents, chemical oxygen demand (COD), coliforms, turbidity and sediment contents. Subsurface-outflow samples from initial trials were high in COD and total dissolved solids, representing soil flushing or leaching. Concentrations of inorganics reached a maximum value within a few hours of initial seepage, and then decreased. The peaking represents a salt build-up between trials. Concentrations of COD, coliforms, turbidity and sediment in subsurface-outflow samples decreased significantly during each trial. Surface-outflow samples had lower turbidity, COD, bacteria and sediment contents than surface-inflow samples. Turbidity, suspended and volatile solids, coliforms and COD in runoff samples may be reduced by grass and soil filtration. Increased grass development and soil settling work to produce a better quality effluent. Quantification of the lysimeter's effectiveness will be useful for urban watershed management.
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Salinity Problems of the Safford Valley: An Interdisciplinary AnalysisMuller, Anthony B. 05 May 1973 (has links)
From the Proceedings of the 1973 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 4-5, 1973, Tucson, Arizona / A change in groundwater quality, averaging approximately +0.13 millimhos electrical conductivity and +35 ppm chloride per year, has been documented between 1940 and 1972 with data from ten long -term sample wells. The decrement in the water quality of the surficial aquifer seems to be attributable to four major mechanisms. An increase in salinity may be expected from leakage of saline water from the artesian aquifer. Such leakage would be stimulated by pumping- caused reduction of confining pressure, and by the puncture of the cap beds by deep wells. Water reaching the aquifer from natural recharge may contribute salts to the system. Such recharging water, if passed through soluble beds, could contribute to the salt. Lateral movement of water through similar deposits may be a contribution, and the concentration and infiltration of agricultural water could also add to aquifer salinity. The economic analysis of the Safford Valley, based on the modeling of a "Representative Farm" analog, indicates that cotton will remain economical to produce on the basis of the projected salinity trends, for a significant time beyond limits of prediction. The analysis indicates that the optimum salt-resistant crops for the area are being cultivated, and, of these, alfalfa will cease to be productive in large areas of the valley by 1990. The entire valley will not produce alfalfa for profit by 2040. The methodologies shown in the paper indicate how pumping influences salinity change and outline salinity control recommendations for the area.
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The Effect of Development on Groundwater in the Parker StripEverett, L. G., Schultz, T. R. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / The 14.6 miles of the Colorado River bounded by Parker Dam and Headgate Rock Dam has been referred to as the Parker Strip. This river reach has become a high use recreation area during the past decade with 4,000 permanent residents and as many as 120,000 water enthusiasts on long weekends. The riparian area of the river is heavily clustered with mobile homes, marinas and public beaches. The means of sewage disposal is exclusively via septic tanks. Recent surveys by the Environmental Protection Agency, Arizona State Department of Public Health and the University of Arizona have localized surface water bacteria levels that may indicate a developing groundwater problem. The geohydrology of the area indicates that the septic tanks are located in Post -Pliocene Colorado River deposits. The deposits are quite thin and relatively narrow. Since the deposits are locally derived sands and gravels, the horizontal hydraulic conductivities are such that a relatively short flow time to the river may result. Intensive evaluation of the degradation of the water quality in these deposits is needed to determine if the ground water supply was jeopardized by septic tank systems.
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A Bacterial Water Quality Investigation of Canyon LakeHorak, W. F., Lehman, G. S. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Fecal coliform counts in relation to number of swimmers along with fecal streptococci counts of water samples from Canyon Lake in central Arizona are reported. The presence of swimmers was related to an increase in fecal coliforms which was attributed to organisms shed from the swimmers and from agitation of the bottom sediments, consequently dispersing much of the bacteria contained in the benthos. From sampling of the swimming areas it was determined that livestock waste was the primary source of pollution (a greater number of fecal streptococci was found than fecal coliforms), but this interpretation could be misleading due to the higher survival rate of fecal strep than that of fecal coliform organisms.
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Wastewater Reuse - How Viable is It? Another LookChase, W. L., Fulton, J. 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 / Even though the Phoenix Metropolitan Area is more fortunate than other areas of the desert southwest because of the dependable Salt and Verde River supplies, they still have water problems. The Central Arizona Project (CAP), which will bring water from the Colorado River, will help those problems. But the CAP will not eliminate them. Improved water resource management will be required to bring water supply and demand back into balance. A key element of any successful water resource management program must be wastewater reuse. The communities are studying reuse through their 208 water quality program and while they are discovering that many opportunities exist they are also discovering that there are also many problems to be solved.
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Water Quality Problem of the Urban Area in an Arid Environment, Tucson, ArizonaHansen, G. 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 / The U.S. Environmental Protection Agency 's two-year 208 area-wide Water Quality Management Study for Pima County, Arizona, is discussed in terms of the specific problems of municipal wastewater effluent, industrial wastewater, urban stormwater runoff, land disposal of residual wastes, septic systems, and construction activities related to the City of Tucson urban area. The primary groundwater and the slow cycling of the hydrologic system in this arid urban environment reduce many water pollution problems to insignificant levels in the short term, (2) there does exist significant long-term pollution problems in the area. These problems include urban stormwater runoff and landfill leachate, and are related to the pollution of groundwater recharge and aquifer water supplies, and (3) there is a strong need for total water resource planning in arid urban areas which includes planning for wastewater reuse, water harvesting, and proper management of groundwater recharge systems.
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Factors associated with the problematical of quality drinking water and public health in the municipality of Abomey-calavi in Benin / Facteurs associés à la problématique de la qualité de l'eau de boisson et la santé des populations dans la commune d'Abomey-calavi au BeninDegbey, Cyriaque 04 May 2011 (has links)
The objective of this research is double: <p>1) to study the factors associated with the problems of quality with drinking water on the physicochemical and biological level in the municipality of Abomey-Calavi in Benin ;<p>2)to study its relationships with public health. <p>The goal is to bring on one hand, the tools of improvement to the quality of water and public health in this commune. In addition, to contribute to the reduction of the rate of morbidity and mortality generated by the diseases related to drinking water contamination in this locality<p><p>Methods:<p>For the purpase of this study, we made a preliminary investigation in the municipality (households 55898 and almost all the households have the traditional wells). In the same way the information provided by the National Society of Water in Benin gave the indications on the level koverage of drinkable water conveyance of the commune. This study carried out within a general logical framework of the durable development based on an DPSIR analysis in the municipality of Abomey-Calavi of the Atlantic district in Benin made it possible to provide information on the main sources of contamination of the drinking water. We also carried out a random sampling of 110 wells and 110 households by taking account into the geographical distribution of the households in the commune. We selected 60 taps and 60 households by random sampling for those using water drink distributed by the national Society of Water in Benin. In each zone or district, three households consuming either well water or tap water were drawn randomly. A retrospective study on the number of cases of the hydrous diseases and other symptoms of hydrous diseases was carried out by consultation of medical registers of the commune from 2007 to 2009. Cases of diarrhoeas used as basic variable of health were compared with the other cases of hydrous diseases available in the files. <p><p>Results:<p>The results show that: the most al the well water taken in the households has temperatures beyond the recommendation of the World Health Organization (25 °C) and 98.2 % have a pH below the normal which is 6.5 to 8.5. We note a strong mercury and cadmium, complete iron, aluminum, nitrate nitrite pollution of the sampled wells (n=110) which is respectively 32.73%, 11.82%,10%, 43.64%, 6.36% and 14.55%. The results of the bacteriological analysis of water revealed that the totality of the wells is contaminated. The germs identified during the analysis of the well water are: Escherichia coli, fecal streptococcus species, bacterial salmonella ,Shigella ,Clostridium perfringens, staphylococcus species,<p> Klebsiella pneumoniae and Pseudomonas aeruginosa Most frequent among these germs are: Escherichia coli (100%), Klebsiella pneumoniae (97.27%), bacterial salmonella and Shigella (96,36%) with regard to the coliformes and enterobacteries. As for the cocci with Gram (+) they are staphylococcus species (97.27%) and the fecal streptococcus (88.18%). It is useful to stress that all the wells are strongly contaminated by Clostridium perfringens (95.45%).<p> The differences between the respective prevalence of parasitic coprology, uroculture, diarrhoeas, pains abdominal and saddles bloody for exposed (45.4%, 71.8%, 76.4% and 59.1%) :those who consume the water of wells not exposed (8.3%, 1.7%,13.3%, 16.7): those who consume tap water, are statistically significant (p<0.001). For diarrhoeas according to the characteristics of the people reached of hydrous diseases and other symptoms of hydrous diseases we have: <p>•\ / Doctorat en Sciences de la santé publique / info:eu-repo/semantics/nonPublished
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