MOLYBDENUM IN THE WATER; DEVELOPING A HYDROSTRATIGRAPHIC FRAMEWORK FOR PARTS OF RACINE AND KENOSHA COUNTIES, WISCONSIN

Residential well water sampling conducted over the last 6 years in Wisconsin’s Racine and Kenosha counties have shown elevated molybdenum levels, exceeding the Wisconsin DNR enforcement standard at some sites. The source of the molybdenum is yet undefined, but has been suggested to be the result of coal ash reuse and disposal. Alternatively, it is possible that molybdenum is being mobilized from a natural source within the glacial deposits or bedrock of the area. The wells draw from both the Pleistocene sand and gravel aquifer and the Silurian Dolomite aquifer. This project aims to develop a hydrostratigraphic framework for both the glacial sediments and the Paleozoic rock in order to identify potential high permeability pathways as well as possible natural sources of contamination. Available subsurface data consists of well logs from local private and municipal wells, which have been used to construct cross-sections and to develop correlations among high permeability units.