The State of California's Division of Oil and Gas (Division) has been regulating oil, gas, and geothermal development for over 75 years. Because the types of oil, gas, and geothermal resources within California vary widely, a thorough plan had to be developed to ensure the proper development and management of the different resources, as well as protect the state's fresh water. One of the Division's main concerns is the injection of associated oil and gas brines and spent geothermal fluids, and the confinement of the fluids in the intended zones. The Division's underground injection program has been developed over the years by experienced engineers to handle a wide variety of injection issues. The Environmental Protection Agency has granted primacy for class II wells and has acknowledg d that the Division's geothermal injection program meets their standards of approval. The Division's program has proven to be successful in protecting the oil, gas, and geothermal reservoirs, and preventing any contamination to the vital fresh waters of the state.