| | 1: | | Title: | | | | | Volume/Number: | 1999 | | | | Issuing Agency: | | | | | Description: | In 1997, the Illinois State Water Survey, at the request of the University of Illinois, initiated a test drilling project that included the construction of several 2-inch diameter observation wells at two sites on the Urbana-Champaign campus. The project concentrated on two areas in which cooling water was needed by the University the North Chiller Plant and the Abbott Power Plant. The purpose of the project was to determine whether sufficient ground-water resources could be located from which to develop a water supply. Exploration at both sites focused on sand-and-gravel materials within the Glasford Formation of Illinoian Age. The main area of interest was the North Chiller Plant at the intersection of Clark and Mathews Streets in Urbana, located in the SE of Section 7, T.19N, R.9E. (Urbana Township), Champaign County. If warranted by test drilling results, a seven-day aquifer test was proposed at the site to investigate the potential of pumping approximately 500 gallons per minute (gpm) from production wells. An area of secondary interest was the Abbott Power Plant between Armory and Gregory Streets and just east of the Illinois Central railroad tracks, located in Section 13, T.19N., R.8E. (Champaign Township). Testing at the Abbott site, if warranted, would examine the feasibility of developing 200 gpm from production wells. Exploratory test drilling at both sites, along with additional information from earlier reports and data on file, led to the following conclusions. The Glasford aquifer is present at most sites across the University of Illinois campus, although it varies considerably in both thickness and texture. The texture of the deposit appears to be finer in test holes south of Green Street. The top of the Glasford sand, near University Avenue, commonly occurs at elevations of 615 to 620 feet. However, the top of the sand at the Abbott Power Plant occurs much lower; the top of the aquifer occurs at about 595 feet. The bottom of the sand is more uniform and occurs at both plants at an elevation of approximately 565 feet. A shallower sand occurs at an elevation of about 640 feet, that is not considered part of the Glasford aquifer. It appears oxidized and occurs just below a very dark brown zone, presumably the Robein Silt. The depth to water in study wells finished in the Glasford aquifer is about 115 feet. Ground-water levels in the Glasford aquifer have a natural fluctuation of about 1 to 2 feet in the test holes. Water levels at the North Chiller Plant did not appear to have been affected significantly by water withdrawals at the Northern Illinois Water Corporation East Well Field. Levels were observed to be similar to levels reported in the 1930s. Water in the Glasford aquifer tends to be alkaline, very hard, high in iron concentration, and at a nearly constant temperature of about 57 degrees F. Although there had been some concern about potential contamination of the Glasford aquifer from fuel spills at the Abbott Power Plant, no contamination was evident in samples taken from test wells constructed for this project. Despite their relative proximity to the former locations of University Wells 10 and 11, no test holes drilled near the North Chiller Plant and Beckman Institute indicated a sufficient thickness of suitable sand material in the Glasford aquifer to warrant construction of a test well to conduct an aquifer test at the desired rate of 500 gpm. Test drilling at the Abbott Power Plant indicated a sufficient thickness of Glasford aquifer present to warrant an aquifer test at perhaps 100 gpm. Accordingly, well designs are recommended for the construction of two test wells or production wells at that site, which might be capable of producing the desired quantity of 200 gpm. | | | | Date Created: | 9 24 2004 | | | | Agency ID: | CR-636 | | | | ISL ID: | 000000000798 Original UID: 999999994043 FIRST WORD: Ground | |
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