1. Dep. of Geological and Environmental SciencesStanford Univ.StanfordCA94305‐2115
2. Dep. of Civil Engineering208 Harbert Engineering Center, Auburn Univ.AuburnAL36849‐5337
3. Environmental Sciences DivisionOak Ridge National LaboratoryP.O. Box 2008Oak RidgeTN37831‐6038