Update, October 19, 2009 — On September 2, 2009, AltaRock Energy Inc. announced it had suspended its drilling operations in the southeast Geysers on the Northern California Power Agency (NCPA) leasehold. AltaRock had planned to redrill NCPA well E-7 into the felsite, the intrusive rock underlying the Geysers steam reservoir, to a total depth of 12,000 ft as part of a DOE-funded Enhanced Geothermal Systems project to demonstrate the ability to create multiple fracture zones in one well. Following the redrill, the plan was to inject at low temperature and pressure to create multiple stimulated zones. E-7 was originally drilled in 1988 and was an active injector at the time of the workover.

An Environmental Assessment was completed, including an analysis of the risk of induced seismicity, for the Bureau of Land Management as part of NEPA/CEQA compliance for the project. The BLM issued a Finding of No Significant Impact (FONSI) with mitigation for the project on June 9, 2009. The BLM and AltaRock are in the process of negotiating a protocol for mitigation of any potential impacts from the stimulation. Separate NEPA compliance is required for the DOE grant and that process is currently in review while AltaRock redesigns its drilling plan with input from NCPA.

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