This award provides one-half the funding required to adapt an existing gas-source mass spectrometer so that it can be used for hydrogen/deuterium isotopic analysis. The instrument is housed in the Department of Geology at the University of Florida, and the University of Florida is committed to providing the remaining half of the funds required. The new capabilities of the instrument are needed in the research projects of eight faculty and their students. These include research in geohydrology, ecosystems, limnology, paleoclimatology, and archeology.