NiSource Midstream Services (NMS) and MarkWest Liberty Midstream & Resources, a partnership between MarkWest Energy Partners and The Energy & Minerals Group, have begun the operations of jointly developed natural gas gathering, processing, and transmission projects in Majorsville, West Virginia.

The Majorsville complex is the first integrated gathering and processing system serving Marcellus production in northern West Virginia, which augments the midstream infrastructure that NMS and MarkWest Liberty independently operate in southwest Pennsylvania.

The gathering and processing facilities are fully contracted and will serve various producers, including affiliates of Chesapeake Energy, Chief Oil & Gas, Consol Energy/CNX Gas, Range Resources, and Statoil.

On 1 August 2010, NMS completed a re-functionalization of pipeline and compression assets in West Virginia and Pennsylvania, including the re-commissioning of the Majorsville compressor station.

The pipeline and compression assets allow NMS to gather and deliver 88,000 dekatherms per day (Dth/d) of liquid-rich Marcellus gas production from Washington and Greene Counties in Pennsylvania and 250,000 Dth/d from Marshall, Wetzel, and Doddridge Counties in West Virginia to the new MarkWest Liberty Majorsville processing plant.

Residue gas from the processing plant is currently delivered into the NGT&S interstate pipeline system and, in October, construction will begin on a pipeline to deliver residue gas to the Texas Eastern Windridge compressor that will provide significant additional outlet capacity to eastern markets. A January 2011 in-service date is planned.

In 2011, MarkWest Liberty plans to expand its cryogenic processing capacity at the Majorsville complex to 270mmcf/d, while concurrently, the Houston cryogenic processing capacity will be expanded from 155 mmcf/d to 355mmcf/d.

MarkWest Liberty is constructing fractionation facility with a capacity of 60,000 barrels per day to accomodate increasing NGL production resulting from the expansions.

The facility will allow for the production of commercial iso-butane, normal butane, and natural gasoline in addition to the current capabilities of producing purity propane.