1. Graduate Research Assistant, Dept. of Civil, Architectural and Environmental Engineering, Univ. of Texas, Austin, TX 78712.
2. Research Associate Professor, Dept. of Civil, Architectural and Environmental Engineering, Univ. of Texas, Austin, TX 78712 (corresponding author).
3. Research Scientist, Texas Institute for Applied Environmental Research, Tarleton State Univ., Stephenville, TX 76402.
4. Deputy Director for Environmental Sciences, Texas Institute for Applied Environmental Research, Tarleton State Univ., Stephenville, TX 76402.