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USGS · sir20195013

Hydraulic conductivity estimates from slug tests in the Big Sioux aquifer near Sioux Falls, South Dakota

Abstract

Hydraulic conductivity estimates were made for 15 observation wells using slug-out (rising-head) tests in the Big Sioux aquifer near Sioux Falls, South Dakota, as part of a cooperative study with the City of Sioux Falls to characterize the hydrogeology and the extent of the Big Sioux aquifer north of the city. Well and aquifer data were collected from field measurements and drillers’ logs. Multiple slug tests were completed at each observation well with a transducer to record the change in water level and a U.S. Geological Survey standard mechanical slug to displace the well’s water column. In total, 110 slug-out test trials were completed among the 15 observation wells. Hydraulic conductivity was estimated by curve fitting with AQTESOLV Pro version 4.50.002. Hydraulic conductivity estimates ranged from 64 to 379 feet per day (ft/d). The mean, standard deviation, and median hydraulic conductivity for the 110 slug-out test trials were 171 ft/d, 73 ft/d, and 157 ft/d, respectively. The mean hydraulic conductivity calculated for each well ranged from 88 to 270 ft/d, the standard deviation ranged from 7 to 66 ft/d, and the median hydraulic conductivity ranged from 86 to 256 ft/d.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 43.462111° to 43.836203° latitude; -96.846997999996° to -96.636738000004° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

William G. Eldridge, Colton J. Medler. 2019-03-21. Hydraulic conductivity estimates from slug tests in the Big Sioux aquifer near Sioux Falls, South Dakota. https://doi.org/10.3133/sir20195013

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