MarkWest Pioneer L.L.C., a wholly owned subsidiary of MarkWest Energy Partners, L.P., held an open season through April 21, 2008, to solicit shipper commitments for firm year-round transportation service on its proposed Arkoma Connector Pipeline.

The transportation service would originate northeast of Coalgate, OK, and extend south to near Bennington, OK, where the Pipeline will interconnect with the proposed Midcontinent Express and Gulf Crossing pipelines. The targeted in-service date for the project is the second quarter of 2009, subject to approval of the Federal Energy Regulatory Commission.

MarkWest will determine the capacity, scope, and cost of the pipeline based on the results of the open season. The estimated throughput capacity of the pipeline is approximately 625,000 Dth/d. To meet the diverse needs of the region’s gas producers, MarkWest anticipates offering firm and volumetric-based transportation service.

Additional information is available at www.markwest.com.