Electromagnetic-Terrain-Conductive And Ground-Penetrating-Radar Investigation At And Near The Ciba-Geigy Superfund Site, Ocean County, New Jersey: Quality Controland Quality Assurance Plan And Results

Ground water is the principal source of drinking water in the<br>vicinity of the Ciba-Geigy Superfund site near Toms River, Ocean County,<br>New Jersey. The presence of earlier identified point sources of<br>organic-compound and, to a lesser extent, metals contamination dt the<br>Ciba-Geigy Toms River Chemical Company Plant has resulted-in severe<br>degradation of ground-water quality and has increased the potentiil for<br>water-supply problems (NUS Corporation, 1988). The point sources of<br>contamination include a manufacturing area, a backfilled-lagoons area, a<br>former fire-prevention training area, several sludge-disposal areas, and<br>a drum-disposal area. A borrow area also is considered a potential<br>source of contamination (Camp Dresser 6 McKee, Inc., 1989).<br>The U.S. Environmental Protection Agency requested that the U.S.<br>Geological Survey evaluate the hydrogeologic conditions in the Kirkwood-<br>Cohansey aquifer system (Zapecza, 1989) and the extent of ground-water<br>contamination on the property of the plant (which includes the Superfund<br>site) and in Winding River Park, which borders the Toms River<br>immediately to the east of the Superfund site (Barton, 1989). This<br>investigation included an electromagnetic-induction survey covering<br>45 line miles throughout the site and a ground-penetrating-radar survey<br>in part of the borrow area.<br>The quality assurance/quality control plan (QA/QC) for the<br>electromagnetic-induction survey established guidelines for performance,<br>system audits, and data validation, and set control limits for<br>instrument and procedural precision. The QA/QC plan for the groundpenetrating-<br>radar survey sets guidelines for performance and system<br>audits.