MarkWest’s Mobley, WV Wet Gas Processing Plant Goes Online Energy Services | Industrywide Issues | MarkWest Energy | Processing Plants | West Virginia | Wetzel County December 13, 2012December 13, 2012 MarkWest Energy today announced the first of it’s three planned Mobley processing plants, located in Wetzel County, WV, is now online and producing. The plant is currently operating at 60% of capacity. MarkWest’s announcement: Please Login to view this content. (Not a member? Join Today!) Related