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Hank Johnson is a hydrologist at the USGS Oregon Water Science Center.
I am a hydrologist with the USGS Oregon Water Science Center. I have been working on groundwater and water-quality issues regionally and nationally for more than 20 years. My research interests include arid-system hydrology, groundwater and spring systems, and environmental tracers.
B.S., Geological Sciences, Virginia Polytechnic Institute & State University, Blacksburg, Virginia, 1992
M.S., Environmental Science and Engineering, Oregon Graduate Institute of Science & Technology, Hillsboro, Oregon, 1996
Despite the tremendous effort invested in reducing the use of nitrogen, widespread decreases in nitrate loads in US rivers and streams remain elusive...