MacClarence

I. Background

A. The Prudhoe Bay Unit

The Prudhoe Bay Unit (PBU) is located on the North Slope of Alaska and extends over 300 square miles. It consists of a MACCLARENCE v. USEPA 3413 series of oil and gas facilities, including thirty-eight drill sites or “well pads” and six production centers, as well as support facilities for PBU workers. GC 1 is one of the six production facilities at the PBU. BP owns approximately 26.35% to 50.7% of the facilities at the PBU, including GC 1, and oper- ates all of the PBU facilities pursuant to an agreement with the other owners. Although the PBU oil field is composed of a number of different oil leases, those leases have been unit- ized or pooled by the State of Alaska so that the field may be exploited efficiently.

The PBU facilities are engaged in a continuum of oil and gas refining activities, from drilling to sale.1 Well pads in the PBU pump “three-phase” crude oil from the tundra beneath the PBU facilities. This oil is transferred to the production centers, including GC 1, where it is separated into processed crude oil, water, and hydrocarbon gases. The processed crude oil is pumped from the production…