Keystone Midstream Services, LLC

From Wikimarcellus

Westminster, Colorado-based Keystone Midstream Services, LLC is a joint venture (JV) formed between Rex Energy Corporation and Stonehenge Energy Resources in December, 2009. The JV was to be 40% owned by Rex and 60% by Stonehenge--the latter to manage it. Each company planned to invest $25 million in Keystone Midstream or a total of $50 million. The new company's focus was to be on building a cryogenic processing plant in Butler County, Pennsylvania for Rex Energy's Marcellus shale production as well as constructing a high pressure pipeline gathering system for bringing gas out from the wellheads in the area to the processing plant. Butler County is located north of Pittsburgh, and in the western part of Pennsylvania.

Update: Keystone Midstream Services, LLC was acquired by Mark West Energy Partners, L.P. in May, 2012 for $512 million.

According to a March, 2010 news account, the processing plant was to be located along side an existing refrigeration plant in Forward Township near the Borough of Connoquenessing. Updates on the status of this facility, known as the Sarsen plant, are available on the Rex Energy wiki page.