Creator
- Geological Survey (U.S.)3
- Hinkle, Stephen R.3
- Bonn, Bernadine A.1
- Butts, Joseph Shirey1
- Harney, Joshua M.1
- National Water Quality Assessment Program (U.S.)1
- Oregon State College. Agricultural Experiment Station1
- Oregon. Water Resources Dept., Geological Survey (U.S.)1
- Polette, Danial J.1
- Washington County (Or.). Unified Sewerage Agency.1