MarkWest Energy Partners Announces Firm Capacity Commitment on Mariner East

MarkWest Energy Partners, L.P. (MarkWest) MWE announced today that it has signed a 10-year agreement to become a firm shipper on the Mariner East pipeline subject to final regulatory approvals. Mariner East is currently designed to transport ethane and propane sourced at MarkWest's Houston, Pennsylvania processing and fractionation complex to Sunoco's Marcus Hook facility located near Philadelphia. Once delivered, the ethane-propane mix will be re-fractionated into purity products for sale into domestic and international markets.