1. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst 01003.
2. Department Head and Professor, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst 01003.
3. Associate, Hazen and Sawyer, 1 South St., Suite 1150, Baltimore, MD 21202.
4. Manager, Dept. of Public Works, City of Baltimore, 18514 Prettyboy Dam Rd., Parkton, MD 21120.