The Alaska Oil and Gas Conservation Commission has approved a request from Hilcorp Alaska to extend enhanced recovery injection order No. 7 for the Milne Point unit Ugnu pilot project through Dec. 31.
The order, ERIO 7, was issued April 14, 2022, and expired in 24 months (April 14, 2024) if injection had not begun.
In its request for extension, Hilcorp said it submitted an annual report to AOGCC March 4 indicating that it planned to begin injection operations in 2025, and on March 14 submitted an application to begin polymer injection in the Ugnu at the Milne Point Unit S-203 well in early June.
The company said it had relied on wording in the ERIO which says the order would expire 3 years after injection activity begins, unless extended by the commission, and said it had only recently become aware that the commission's regulations say an ERIO expires if injection has not begun within 24 months of the date of the order.
In its extension order the commission said the ERIO 7 "rule was not written clearly so there is ambiguity as to when ERIO 7 actually expires." It clarified the language in the ERIO and granted Hilcorp's extension request.
Ugnu polymer injection
When Hilcorp applied for pilot enhanced oil recovery at Ugnu in November 2021, it told the commission it was proposing polymer injection at the Milne Point S Pad and said polymer was not currently approved for EOR for that area, noting that prior temporary administrative approval for water and gas injection into the Ugnu had expired.
Hilcorp said the project built on work begun by BP in 2003 and was designed to "gather the data necessary to determine the appropriate spacing for paired Ugnu producer and injection wells at S-pad. If the pilot proves successful, potential exists to justify a project throughout the field, including the establishment of formal pool and area injection rules for the MPU Ugnu sand."
Hilcorp said two horizontal injectors would be used to support the existing S-203 which was drilled and brought online in 2010. That well is producing but "requires pressure support from injection wells," Hilcorp said.
The company said the pilot would "test the economic viability of waterflooding and polymer flooding in the Ugnu sand."
With polymer injection, total recovery is expected to reach some 9.25% of Ugnu original oil in place, the company said, compared with 4-8% OOIP recovery with primary depletion.
Hilcorp said an existing horizontal well, S-22, would be converted to an injector during the pilot program. The company also said it planned to drill a new injector, S-204, to offset the S-203 producer opposite the S-22.
AOGCC data show S-204 was permitted on April 4 of this year.
Hilcorp is already using polymer injection at Milne Point for Schrader Bluff recovery.
In its 2022 approval of the ERIO for polymer injection use in the Ugnu formation, the commission noted that injection began at Schrader Bluff in 2018, with Hilcorp projecting that it expected polymer to increase Schrader recovery from 10-15% of oil in place at Milne to as much as 50%.
--KRISTEN NELSON
