1. Division of Earth and Ocean
Sciences, Nicholas School of the Environment, Duke University, Durham, North Carolina 27708, United States
2. Department of Earth Science, University of Arkansas at Little Rock, Little Rock,
Arkansas 72204, United States
3. Civil and Environmental Engineering,
Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
4. Surface Water Protection Section, Division
of Water Quality, North Carolina Department of Environment and Natural Resources, Raleigh, North Carolina 27609,
United States