1. Envir. Engr., U.S. Envir. Protection Agency, Nat. Risk Mgmt. and Res. Lab., P.O. Box 1198, Ada, OK 74820; corresponding author. E-mail:Huling.Scott@EPA.GOV
2. Prof., Dept. of Chemical and Envir. Engrg., Univ. of Arizona at Tucson, Tucson, AZ 85721.
3. Prof., Dept. of Chemical and Envir. Engrg., Univ. of Arizona at Tucson, Tucson, AZ.
4. Chemist, U.S. Envir. Protection Agency, Nat. Risk Mgmt. and Res. Lab., P.O. Box 1198, Ada, OK.
5. Chemist, ManTech Environmental Research Services Corp., P.O. Box 1198, Ada, OK.