1. a Ch2M HILL, 1766 Sea Lark Lane, Navarre, FL 32566; Tel: (850) 939-8300 ext. 37, (850) 939-0035 (Fax), bliu@ch2m.com.
2. b School of Civil Engineering, Purdue University, West Lafayette, IN 47907; Tel: (765) 496-3424, (765) 496-1107 (Fax), kbanks@ecn.purdue. edu.
3. c Department of Agronomy, Purdue University, West Lafayette, IN 47907; Tel: (765) 496-3602, (765) 496-2926 (Fax), pschwab@purdue.edu.