Precision directional drilling of hot-dry-rock geothermal production well EE-3

The deviated directional drilling of the hot dry rock (HDR) geothermal production well EE-3 (Energy Extraction No. 3) was successfully completed on August 1981. The injection well, EE-2, previously had been drilled with its lower part at an inclination of 35/sup 0/ to the vertical. It reached an on-line depth of 15,292 feet and its bottom-hole temperature was 608/sup 0/F (320/sup 0/C). The production well EE-3 was required to be drilled 1200 feet (370 m) above and parallel to the injection well. This necessitated high precision, controlled-trajectory directional drilling operations. The directional drilling of EE-3 was accomplished within the required tolerances at a depth of 13,933 feet and a bottom-hole temperature of 580/sup 0/F (280/sup 0/C)