This is a new program (since 1996) that was created to provide expertise, support,and education in groundwater hydrology to those that care about, manage, plan, and impact California's groundwater resources. The program is run by Thomas Harter (Phone: 530-752-2709) who spends approximately 40% of his time on cooperative extension activities in this program. These activities include presentations to industry/professional/interest groups in water resources and agriculture on a number of groundwater quality related topics; organization of seminars, workshops, and shortcourses; preparation of teaching materials; advise to citizens, citizens groups, and professionals; and publication of groundwater information for professionals and citizens in the state of California. Funding for this UC cooperative extension program is primarily provided through the State of California. The program is housed in the Department of Land, Air, and Water Resources at UC Davis and at the Kearney Agricultural Research Center.