CONOCOPHILLIPS ALASKA, INC. — Integrity Assurance Notification

TECHNOLOGYConocoPhillips Alaska, Inc., as operator of the proposed Willow Sales Oil Pipeline and the proposed Western North Slope (WNS) Ultra-low Sulfur Diesel (ULSD) Pipeline requests your review and approval to use alternative technology in lieu of valves required under 49 CFR § 195.260(e). The enclosed report, Pipeline Vertical Loop Evaluation, represents a Best Available Technology (BAT) review analysis for the use of vertical loops as an alternative to placing valves on either side of water crossings more than 100 feet wide from high-water mark to high-water mark for both proposed pipeline systems. You will note in the report, which models spills from small pinhole leaks up to catastrophic failure, that the proposed technology reduces spill volumes below what would be anticipated from a similar system utilizing valves under the scenarios container therein. Many spills on pipeline systems are associated with valve leaks or failures. The proposed alternative vertical loop system and elevation profile leveraging design, in addition to providing better protection than valves, also eliminates potential spills that would be attributed to valve leaks or failures. This design additionally minimizes damage or pollution from accidental hazardous liquid discharge, as appropriate for the area of travel.#