Many challenges arise when cementing geothermal wells. Lost circulation and temperature are

the main culprits for increased cost when trying to achieve zonal isolation. At the Puna

geothermal field, extreme lost circulation and bottom hole static temperatures in excess of 500°F

are not uncommon. The extreme conditions, coupled with the remoteness to drilling service

providers, represent a significant challenge. Reverse cementing was used to successfully

complete a job in a challenging environment and also significantly reduce cost in the cementing

phase of well completion. A demonstration of proper planning, designing, and execution of the

job is presented.