Study Identifies Pathways of Ground-Water Flow and Contaminant Migration at the Byron Superfund Site near Byron, Illinois

Water-level mapping, geophysical logging, aquifer testing, and other techniques were utilized to determine the relation between geology and ground-water flow through the fractured-rock aquifer underlying the Byron Superfund Site near Byron, Illinois. This relation, combined with analysis of the location of contaminants, has helped determine the pathways of ground-water flow and contaminant migration in this area according to a report released by the U.S. Geological Survey, Department of the Interior.

Robert Kay, U.S. Geological Survey hydrologist and principal author of the report, noted that pollution of the shallow fractured-rock aquifer by industrial wastes is a problem in north-central Illinois. "Knowledge of the location of pathways for ground-water flow is essential for efficient identification of contaminant location," Kay said. "Ground water and the compounds dissolved in the ground water move preferentially through those parts of the aquifer with relatively large fractures. Because the number and size of fractures in the aquifer can depend on the composition of the rock that composes the aquifer, thorough characterization of the geology can enable investigators to determine the areas affected by a waste-disposal site by focusing on those parts of the aquifer most likely to yield useful data. This also makes it easier to efficiently remediate the aquifer," Kay added.

Kay said that the shallow ground water moves most readily through the middle part of the fractured-rock aquifer from areas where the elevation of the land surface is higher toward areas of lower elevation where the aquifer is heavily fractured. Contaminants in the ground water also tend to migrate along the fracture pathways.

The report, titled "Geology, Hydrology, and Ground-Water Quality at the Byron Superfund Site Near Byron, Illinois," by Robert T. Kay, Douglas J. Yeskis, William J. Bolen, James R. Rauman, and Scott T. Prinos is published as U.S. Geological Survey Water-Resources Investigations Report 95-4240. Copies are available for inspection at the U.S. Geological Survey, 221 N. Broadway Ave., Urbana, Ill. Paper and microfiche copes can be purchased at cost from the U.S. Geological Survey, Branch of Information Services, Box 25286, Federal Center, Denver, CO 80225-0046 (telephone (303) 202-4700). Orders must include check or money order payable to U.S. Department of Interior-USGS and must specify report number WRIR 95-4240.