Rocky Mountain Pipeline System LLC Announces Open Season for Proposed Crude Oil Transportation Route from Fort Laramie, Wyoming to Cushing, Oklahoma

Rocky Mountain Pipeline System LLC (“RMPS”), an indirect subsidiary of Plains All American Pipeline, L.P. (NYSE:PAA), announced today that it is conducting an open season for committed capacity on a proposed crude oil transportation route from Fort Laramie, Wyoming to Cushing, Oklahoma. The open season process provides an opportunity for potential shippers to offer long-term volume commitments for service between Fort Laramie, Wyoming and Cushing, Oklahoma in exchange for a discounted rate.

The proposed transportation route would originate at RMPS’ Fort Laramie station in Wyoming, which currently receives crude oil from several sources, including the Big Horn, Platte and Butte pipelines. From the Fort Laramie station, oil movements would progress as follows:

* The Fort Laramie to Cheyenne, Wyoming movement would be on RMPS’ existing 16-inch Cheyenne Pipeline System;
* The Cheyenne to Platteville, Colorado movement would be on a newly constructed 12-inch pipeline; and
* The Platteville to Cushing, Oklahoma movement would be on a planned 12-inch pipeline to be constructed by White Cliffs Pipeline L.L.C.

By submitting a binding proposal, bidders are offering to enter into a long-term throughput and deficiency agreement for pipeline capacity. Interested parties should contact Gregg Werger, Manager – Pipeline Commercial Operations at (303) 572-4906 or gawerger@paalp.com. A complete package of open season documents is available online under RMPS Open Season tab of Customer Center section of PAA’s website at www.paalp.com. The open season begins on May 13, 2008 and will end at 5:00 P.M. CDT on June 12, 2008.