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ARCO presents Point McIntyre enhanced oil recovery plan Water alternating gas expected to increase recovery by 6 percent; waterflood at West Beach could add 10-15 percent Kristen Nelson PNA News Editor
Enhanced oil recovery is expected to increase recovery from the Point McIntyre field on the North Slope by 6 percent, an additional 32 million barrels of oil within the current waterflood area, while waterflood at West Beach is estimated to add an additional 10-15 percent of the 15-25 million barrels of original oil in place.
Those were the projections ARCO Alaska Inc. gave the Alaska Oil and Gas Conservation Commission Jan. 13 when the company requested area injection and pool rules for the fields on behalf of itself and partners BP Exploration (Alaska) Inc. and Exxon at Point McIntyre and Exxon at West Beach.
At Point McIntyre, ARCO told the commission, gas re-injection began when production started in October 1993 and waterflood for pressure maintenance began in July 1994. The Point McIntyre field lies offshore north of Prudhoe Bay and has been developed from two onshore drill sites.
Point McIntyre production is processed at the Lisburne production center and reached a facility-constrained plateau of 165,000 barrels of oil per day during the second quarter of 1996 and has declined since late 1997 due to increasing water cuts at Point McIntyre and water handling constraints at the Lisburne facility.
Point McIntyre working interest owners (ARCO, BP and Exxon) approved a hydrocarbon miscible EOR project for Point McIntyre with planned startup during the first half of this year.
Seventy-four wells have been drilled at Point McIntyre and ultimate well count at the field could be as high as 86 wells.
The Point McIntyre EOR project, ARCO said, involves the eventual conversion of the existing 15 waterflood injectors and potentially any future water injectors to water-alternating-gas service. Water will be injected alternately with miscible injectant in the WAG injection wells to improve the MI sweep in the reservoir.
MI generated at Lisburne will be delivered to Point McIntyre at a rate of about 50 million standard cubic feet a day for the next 23 years. Of 15 patterns at Point McIntyre, two are expected to be receiving MI at any one time; peak incremental oil rate is expected to exceed 5,000 barrels a day as a result of the project.
Current Point McIntyre field operations, processed gas re-injection and waterflood, are expected to yield an estimated total recovery of 42-45 percent of original oil in place, ARCO said, with EOR expected to result in recovery of an additional 32 million barrels, approximately 6 percent.
West Beach waterflood proposed Like Point McIntyre, West Beach lies offshore and has been developed from an onshore drill site. Production began in April 1993, ARCO told the commission, and the field has been delineated by 11 penetrations — seven wells and four sidetracks. Secondary recovery plans include water injection using water produced from a new well on the West Beach pad. Estimates of additional recovery from waterflood are 10-15 percent of the estimated 15-25 million barrels of original oil in place.
Most of the West Beach portion of the hearing was confidential and closed to all but commission and owner companies. ARCO said in the public portion of the hearing that it had no plans to drill additional production wells at the field until it sees the response from waterflooding.
An existing production well at West Beach would be converted to injection service in the first quarter of 2000, ARCO said. The source water well would supply injection water with an electrical submersible pump; the source water well is currently being drilled.
ARCO said that augmenting water injection at West Beach with gas re-injection is also being evaluated.
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