English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The U.S. Geological Survey is studying the geologic, hydrologic, and geochemical properties of the glacial drift and underlying bedrock at a low-level radioactive-waste burial site in the Palos Forest Preserve, 22 kilometers southwest of Chicago. Data collected from the 33 test wells drilled into the drift plus data from 4 wells drilled into the underlying dolomite bedrock are presented. Data include maps showing the location of the test wells, a general description of the drift, well-construction information, and lithologic descriptions of cores from the wells finished in the drift. INTRODUCTION In early 1943, the U.S. Army Corps of Engineers leased land from the Cook County Forest Preserve District to build a radioisotope research facility. The facility formed part of the Metallurgical Laboratory operated by the University of Chicago for the Manhattan Engineer District (the Manhattan Project). The facility, known as Site A (fig. 1), housed the world's first nuclear reactor. Plot M was the burial site for the low-level radioactive waste resulting from operations at the Metallurgical Laboratory. The Argonne National Laboratory (ANL) has conducted a radiological monitoring program at Plot M since 1948. In 1954, at the request of ANL, the U.S. Geological Survey (USGS) studied the geologic, hydrologic, and chemical characteristics of the glacial drift at Plot M (W. J. Drescher, written commun., 1954) and advised ANL on its environmental monitoring program. In 1973, tritium was detected in water from a dolomite bedrock well at the Red Gate Woods picnic area. Consequently, the ANL monitoring program was expanded to include the Red Gate Woods well and other nearby forest preserve wells. This study of ground-water flow and tritium migration at Plot M began in 1978. The two main objectives of the study are to determine the geologic, hydrologic, and geochemical properties of the drift that control the migration of tritium from the burial site to the underlying bedrock and to determine the present extent of tritium in the drift. A third objective is to determine the rate and direction of tritium movement in water in the bedrock. The results of the study are needed by the U.S. Department of Energy to evaluate the need for remedial action at the Plot M site. Several test wells were drilled to help accomplish these objectives. The purpose of this report is to present the physical description of each well and a description of the lithologic materials encountered. ACKNOWLEDGMENTS This investigation relied heavily on the Plot M environmental surveillance program by the Argonne National Laboratory. Especially helpful have been J. Sedlet, N. W. Golchert, and H. C. Svoboda of the Health Safety Section of ANL who have provided administrative and technical assistance throughout the project. DRILLING PROGRAM The Plot M site is situated on a moraine and is directly underlain by 25-30 meters of clayey silt. The clayey silt, which is the Wadsworth Till Member (of Willman and Frye, 1970) of the Wedron Formation, contains thin lenses and layers of sand and gravel and overlies sandy silt and gravel of the Maiden Till Member (of Willman and Frye, 1970) of the Wedron Formation. The total thickness of the drift beneath the site ranges from 25 to 45 meters. In 1976, under USGS supervision, ANL began construction of a network of test wells in the drift (fig. 2). Drilling at each site was accompanied by continuous split-spoon sampling to identify variations in lithologic properties, Cores and samples were logged in the field and sealed for laboratory analysis. Field observations were made of the lithology, texture, color, structure, and sedimentologic features of each sample. Vertical variations in lithology, grain-size distribution, and color were observed within both the Wadsworth and Maiden tills. These vertical variations in the character of the drift were consistent at all test wells and were used to categorize the drift into seven lithostratigraphic units. The units are referred to, from the surface downward, as Units 1 through 7 (table 1). Units 1 through 5 represent the Wadsworth Till Member and Units 6 and 7 represent the Maiden Till Member. Table 2 includes information on the length of core recovered and the geologic log of each well finished in the drift. Table 3 includes the wellcompletion information for the four bedrock test wells drilled near Plot M (fig. 1) in 1976. A complete description of the techniques used to drill the pre-1979 wells, together with the results of the radionuclide analyses of all the core samples collected, is given by Golchert and Sedlet (1978). REFERENCES Golchert, N. W., and Sedlet, Jacob, 1978, Radiological survey of Site A and Plot M: U.S. Department of Energy Report DOE/EV-0005/7, 89 p. Willman, H. B., and Frye, J. C., 1970, Pleistocene stratigraphy of Illinois: Illinois State Geological Survey Bulletin 94, 204 p.

Data for wells at the low-level radioactive-waste burial site in the Palos Forest Preserve, Illinois