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Property Tax Appeal Board Decision 2006-20991-R-1 Mulkeen

Part of: Electronic Documents of Illinois

Property Tax Appeal Board Decision 2006-20991-R-1, Mulkeen , Appellant, Cook County, River Forest Township,

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Property Tax Appeal Board Decision 2006-20427-R-1 Garcia

Part of: Electronic Documents of Illinois

Property Tax Appeal Board Decision 2006-20427-R-1, Garcia, Appellant, Cook County, Oak Park Township,

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Property Tax Appeal Board Decision 2006-22336-R-1 Trusina

Part of: Electronic Documents of Illinois

Property Tax Appeal Board Decision 2006-22336-R-1, Trusina, Appellant, Cook County, Proviso Township,

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Property Tax Appeal Board Decision 2006-21261-C-2 Hazel Crest, LCC

Part of: Electronic Documents of Illinois

Property Tax Appeal Board Decision 2006-21261-C-2, Hazel Crest, LCC , Appellant, Cook County, Bremen Township,

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Property Tax Appeal Board Decision 2006-22566-R-1 Oxford Estates, Inc.

Part of: Electronic Documents of Illinois

Property Tax Appeal Board Decision 2006-22566-R-1, Oxford Estates, Inc., Appellant, Cook County, Rich Township,

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Groundwater availability in Champaign County

Part of: Electronic Documents of Illinois

An estimated 23.3 million gallons of water is pumped from the aquifers of Champaign County each day to satisfy industrial, municipal, domestic, and rural needs. A much larger quantity of water, perhaps as much as 90 million gallons a day (mgd), could probably be withdrawn without overdevelopment. Maps and tables indicating the probable maximum depths of wells, water levels, chemical quality, and general groundwater conditions for each water-bearing unit at specific locations are presented to serve as a guide in the development and utilization of the groundwater resources of Champaign County.

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Groundwater resources of the buried Mahomet Bedrock Valley

Part of: Electronic Documents of Illinois

The buried Mahomet Bedrock Valley and its major tributaries cover an area of about 3700 square miles in east-central Illinois. Large supplies of groundwater chiefly for municipal use are withdrawn from wells in permeable sands and gravels in thick deposits of glacial drift in the area. The glacial drift exceeds 400 feet in thickness in places. The largest source of groundwater consists of the sands and gravels of the Kansan deposits, called the deep aquifer, which occupy the deepest portions of the Mahomet Valley channel. Intercalated in the glacial drift above the Kansan deposits are sands and gravels of the Illinoian deposits, called the middle aquifer. The middle aquifer is a secondary source of groundwater. The coefficients of permeability and storage for the middle aquifer range from 230 to 4080 gallons per day per square foot (gpd/sq ft) and from 0.00001 to 0.083, respectively. They range from 310 to 4100 gpd/sq ft and from 0.000022 to 0.0023, respectively, for the deep aquifer. The coefficients of the vertical permeability of the confining beds above the middle and deep aquifers range from 0.0026 to 0.04 gpd/sq ft and 0.005 to 0.42 gpd/sq ft, respectively. Pumpage from wells increased from 8.5 million gallons per day (mgd) in 1890 to 46.3 mgd in 1960 and was 40.2 mgd in 1965. Of the 1965 total pumpage, 64.2 percent was for municipal supplies, 19.1 percent was for rural uses, and 16.7 percent was for industrial use. Wells in the deep aquifer accounted for 49.3 percent of the 1965 total; wells in the middle aquifer, 31.8 percent; wells in shallow unconsolidated deposits, 17.4 percent; and wells in bedrock aquifers, 1.5 percent. Major pumping centers with pumpage exceeding 1 mgd are located at Champaign-Urbana, Rantoul, Lincoln, Taylorville, and Hoopeston. As a result of heavy pumpage, water levels in the middle aquifer at Champaign-Urbana declined as much as 100 feet between 1885 and 1947. Subsequent shifting of pumpage to the deep aquifer west of Champaign resulted in water levels in the middle aquifer recovering from 30 to 55 feet. Because of increased withdrawals, water levels in the deep aquifer declined some 35 feet during 1948- 1963. Recovery of water levels in 1964 and 1965 resulted from a decline in pumpage. Similar though smaller water-level declines have occurred in many of the other pumping centers in the Mahomet Valley area. Recharge to buried aquifers in the Mahomet Valley occurs chiefly as leakage of water from a source bed in the shallow deposits across a confining layer. Potential recharge to these aquifers, considering only available head losses across the confining layers, is great. Computations for the Illinoian aquifer at Champaign-Urbana indicate a recharge rate of 115,000 gpd/sq mi in 1947. Similar computations for the Kansan aquifer west of Champaign during the period 1953 through 1965 indicated an average recharge rate of 107,000 gpd/sq mi. Total groundwater runoff for the valley is estimated to be about 740 mgd during years of normal precipitation. It is not unreasonable to assume that existing and/or future pumping centers could capture 60 percent of groundwater runoff, or 445 mgd. An electric analog computer consisting of an analog model and associated electronic equipment was constructed for the middle and deep aquifers and their confining and source beds in the vicinity of Champaign-Urbana to aid in studying the effects of groundwater pumpage on water levels in the Mahomet Valley. The accuracy of the computer was established by a study of records of past pumpage and water levels in three observation wells. The analog computer was used to determine pumping levels with a selected scheme of pumping from existing and future large capacity wells in the Kansan aquifer west of Champaign. Withdrawals with the selected pumping scheme would total 30.3 mgd from existing large capacity wells and 15 mgd from five future wells; pumping levels would be above the top of the Kansan aquifer.

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$Miniature of High-throughput computing for the analysis of tracer tests in fractured aquifers.$

High-throughput computing for the analysis of tracer tests in fractured aquifers.

Part of: Electronic Documents of Illinois

Traditional approaches to characterization and modeling of fractured dolomite aquifers face many conceptual and technical challenges. One alternative strategy begins with the Generalized Radial Flow interpretation of hydraulic tests, which infers an additional parameter, the flow dimension, to describe the geometry of groundwater flow. This study examines the behavior and variability of the apparent flow dimension, n*, and advective transport for four stochastic models of heterogeneous transmissivity, T(x). This is accomplished through Monte Carlo analysis of numerical models simulating aquifer tests and converging flow tracer tests (CFTTs) in two-dimensional systems. For ln T(x) distributed as a multivariate Gaussian (mvG) variable of variance less than one, the apparent flow dimension of an aquifer test converges to n* = 2 if the scale of the test is large relative to the scale of correlation. The variability of the apparent flow dimension depends on the variance and integral scale of the transmissivity, suggesting that it may be possible to identify the variance and integral scale from a set of aquifer tests. For variances greater than one, the results suggest that the average of the apparent flow dimension is less than two initially, then converges to n* = 2, similar in some respects to a percolation network. The simulation of an uncorrelated log-Gaussian model suggests that the flow dimension of an aquifer test converges to n* = 2 even for large variances. For ln T(x) distributed as fractional Brownian motion (fBm), the apparent flow dimension averages to n* = 2 and its variability increases with time. An approximation of a percolation network model showed an average apparent flow dimension stabilizing between n* = 1.4 to 1.6, followed by an increasing trend. These characteristics apparently are functions of the transmissivity contrast between the percolating and nonpercolating fractions. In the low-variance mvG, uncorrelated log-Gaussian, and fBm models, CFTTs influenced by matrix diffusion showed late-time breakthrough curves (BTCs) with log-log slopes of -3/2, the characteristic behavior of matrix diffusion. In the percolation network model, a simulated CFTT influenced by matrix diffusion had late-time BTC with log-log slopes of -5/4, attributed to slow advection through low transmissivity regions. This indicates that some heterogeneity models can systematically affect the late-time behavior of a BTC for a CFTT. These results suggest that the flow dimension may be a useful diagnostic for selecting models of heterogeneity, and that flow dimensions n ? 2 may be associated with unique tracer behavior. Additional research is advocated to infer the general behavior of the flow dimension at various field sites, to assess a broader range of parameters, to examine other stochastic models, and to conduct a more detailed examination of transport behavior versus the flow dimension.

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Illinois Charter School Annual Report

Part of: Electronic Documents of Illinois

This report is submitted in compliance with Section 27A-12 of the Illinois Charter Schools Law 105 ILCS 5/27A-12 . The law requires that the report to the General Assembly: i. compare the performance of charter school pupils with the performance of ethnically and economically comparable groups of pupils in other public schools who are enrolled in academically comparable courses, ii. shall review information regarding the regulations and policies from which charter schools were released to determine if the exemptions assisted or impeded the charter school in meeting their stated goals and objectives, and iii. shall include suggested changes in State law necessary to strengthen charter schools.

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Illinois Budget Crisis: A Record of Fiscal Mismanagement

Part of: Electronic Documents of Illinois

House minority presentation of the State of Illinois fiscal condition comparing the Blagojevich administration's management to previous administrations. Figures and graphs show the impact of borrowing on the future of Illinois' fiscal position from the minority party viewpoint.

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