1. Research Associate, Geological Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706 (corresponding author).
2. Wisconsin Distinguished Professor, Director of Sustainability Research and Education, and Chair, Civil and Environmental Engineering, Geological Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706.
3. Professor, Geological Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706.
4. Professor and Head, Dept. of Civil, Construction, and Environmental Engineering, North Carolina State Univ., Raleigh, NC 27695-7908.