Management of Artificial Recharge Wells for Groundwater Quality Control
AuthorWilson, L. G.
AffiliationWater Resources Research Center, University of Arizona, Tucson
KeywordsWater resources development -- Arizona.
Hydrology -- Arizona.
Hydrology -- Southwestern states.
Water resources development -- Southwestern states.
Water quality control
Modes of action
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RightsCopyright ©, where appropriate, is held by the author.
Collection InformationThis article is part of the Hydrology and Water Resources in Arizona and the Southwest collections. Digital access to this material is made possible by the Arizona-Nevada Academy of Science and the University of Arizona Libraries. For more information about items in this collection, contact email@example.com.
PublisherArizona-Nevada Academy of Science
AbstractRecharge 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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