Haas

CHARLES N. HAAS, PhD, is L. D. Betz Professor of Environmental Engineering in the School of Environmental Science, Engineering and Policy at Drexel University in Philadelphia, Pennsylvania.
JOAN B. ROSE, PhD, is Professor in the Department of Marine Science at the University of South Florida in St. Petersburg.
CHARLES P. GERBA, PhD, is Professor in the Department of Soil and Water Science at the University of Arizona in Tucson.