1. Research Civil Engineer, Engineer Research and Development Center–Cold Regions Research and Engineering Laboratory, 72 Lyme Rd., Hanover, NH 03755 (corresponding author).
2. Microbiologist, Engineer Research and Development Center–Cold Regions Research and Engineering Laboratory, 72 Lyme Rd., Hanover, NH 03755.
3. Research Physical Scientist, Engineer Research and Development Center–Cold Regions Research and Engineering Laboratory, 72 Lyme Rd., Hanover, NH 03755.