USG Services will fund and manage the repairs of production wells RRG-2 and RRG-7. RRG-2 was shut down in June 2010 after a pump failure. RRG-7 has a leak in a cement seal that failed where two steel casing sections overlap, allowing cooler geothermal fluid to enter the well bore.
The flowing production temperature in RRG-7 declined from 299 degrees F to 240 degrees F over the past two years. A pump rig was mobilized to the Raft River site on May 16 and began working on well RRG-2. Once the repairs are complete, the plant’s annual average output is expected to increase 25 percent from 8 MW annual average to around10 MW.
In addition to the repairs, a flow stimulation technique called deflagration will be applied to wells RRG-2 and RRG-7 which may increase fluid flow from the known production zones.
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