1. Department of Chemistry and the New Mexico Bureau of Geology and Mineral Resources, New Mexico Institute of Mining and Technology, Socorro, NM 87801
2. Department of Civil Engineering and Geological Sciences, University of Notre Dame, Notre Dame, IN 46556
3. Department of Civil Engineering and Geological Sciences, University of Notre Dame, Notre Dame, IN 46556. Phone: 574-631-9494; Fax: 574-631-9236; E-mail: pmaurice@nd.edu