| Abstract |
Steam deliverability of the original 20 wells, supplying steam to PG&E Unit 13 power plant, has undergone annual exponential decline rates of 11.5%, 5%, 9%, 28.6%, 24% and 18.6% during 1980-81, 1983-84, 1985-86, 1987-88, 1988 and 1989 respectively. High decline rates after 1984 were influenced by the regional effects associated with the installation of new capacity in the adjoining areas totalling 383 MW (net) in 1983-84 and 347 MW (net) in 1985-86. Unit 13 production declined harmonically for the first 6.6 years, nearly exponentially for the next year and hyperbolically to harmonically thereafter. The near exponential decline trend resulted from the combined effect of local and regional pressure drawdowns and an accelerated makeup well drilling program. |