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Commission issues Prudhoe orders Hearing set for proposed Kuparuk, Alpine, Milne well pressures rules Kristen Nelson Petroleum News Editor-in-Chief
The Alaska Oil and Gas Conservation Commission has issued rules regulating sustained annulus pressures in Prudhoe Bay development wells. The commission has also set a public hearing for Aug. 5 on proposed rules governing annular pressures in development wells in the Kuparuk River field, the Colville River field (Alpine) and the Milne Point field. BP Exploration (Alaska) operates the Prudhoe Bay and Milne Point fields. ConocoPhillips Alaska operates the Colville River and Kuparuk River fields.
In its June 26 order establishing rules for regulating sustained annulus pressures in Prudhoe Bay wells the commission said BP's recently revised Prudhoe Bay annular pressure management policies “provide a reasonable starting point for establishing rules regulating annular pressure.” But, the commission said, those policies should be supplemented by a rule requiring BP to notify the commission when “wells exhibit annular pressures that exceed specific thresholds,” submission by the operator of proposed corrective actions for affected wells, specific annular pressure limits necessitating corrective action and “operator accounting for annular pressure increases due to well heating during start-up.”
The commission said engineered solutions may be developed in the future which satisfy some of the objectives of its rules. Results must be available for inspection The rules adopted include: a requirement for pressure testing of tubulars and completion equipment in development wells when it is installed or replaced; daily monitoring to check for sustained pressure — with an exception for extreme weather conditions, emergency situations or other unavoidable circumstances.
The commission is also requiring daily monitoring results be available for its inspection.
BP is required to notify the commission within three working days after a well is identified as having sustained inner annular pressure exceeding 2,500 pounds of pressure per square inch (for Lisburne processing center wells) or 2,000 psi for other Prudhoe development wells, or sustained outer annular pressure exceeding 1,000 psi. The commission also may require a proposal for correction action or increased surveillance for development wells with sustained pressure that exceeds the limits set, and may require corrective action to be verified by mechanical integrity testing or other diagnostic tests.
The operator also must notify the commission within three working days if it identifies sustained pressure in the inner annular of a development well that exceeds 45 percent of the burst pressure rating of the well's production casing for inner annulus pressure or sustained pressure in the outer annulus that exceeds 45 percent of the burst pressure rating of the well's surface casing for outer annulus pressure. Unless emergency corrective action is required, the commission said it wants to approve the proposal for corrective action.
The commission is also requiring that before a shut-in well in placed in service, any annulus pressure must be relieved sufficiently that inner annulus pressure at operating temperature will be below 2,500 psi for Lisburne processing center wells and below 2,000 psi for other development wells, and that the outer annulus pressure at operating temperature will be below 1,000 psi. Kuparuk River, Colville River, Milne Point rules proposed The commission's proposed rules for Kuparuk, Colville and Milne Point wells are similar to the commission's just-adopted Prudhoe rules, with sustained pressures exceeding 2,000 psi for the inner annulus and 1,000 psi for the outer annulus the trigger points. The commission requires notification within three days of wells that exceed those pressure limits and may require a proposal of corrective action.
As with Prudhoe Bay wells, if pressure in the inner annulus exceeds 45 percent of the burst pressure rating of production casing or outer annulus pressure exceeds 45 percent of the burst pressure rating of surface casing, the operator must notify the commission within three working days and take corrective action. Unless emergency action is required, the commission wants to approve the operator's proposal.
The commission is also requiring annulus pressure be relieved before a shut-in well is placed in service to bring inner annulus pressure at operating temperature below 2,000 psi, and outer annulus pressure below 1,000 psi.
The commission said its consolidated public hearing is tentative, and if it receives no written requests for a hearing by July 31, it may decide to issue orders without a hearing.
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