The experimental well, HGP-A, drilled under the auspices of the Hawaii Geothermal Project, is located on the island of Hawaii near the eastern rift of Kilauea volcano. Drilling was completed to a depth of 6450 feet in April 1976. The well is cased to 2230 feet below the surface, which is 600 feet above sea level, with a slotted liner running from the end of the casing to bottomhole. Cuttings and core samples obtained during drilling indicate that the region is composed of volcanic basalt with a profile that contains a zone of open fractures (3300-4500 feet) and a zone of partially sealed fractures (4500-6450 feet) as shown in Figure 1. Conclusions from preliminary test results and analyses: the Kapho Geothermal Reservoir is liquid-dominated, with permeability thickness of ~ 1000 md-ft, very high temperatures ~ 350°C, high formation pressure ~ 2000 psi, slightly brackish water, and high silica content, and is potentially large; the HGP-A Geothermal Well borehole contains steam and water at saturation during flash; flashing occurs in formation; the well has high wellhead pressures ~ 160 psi at 50 Klb/hr steam, probably has severe skin damage, and potential power output ~ 3.5 MWe; the well’s producing regions aremore » probably at bottomhole and 4300 feet; well flows have increased with each test. 5 figs., 5 tabs.« less