Bearcub Energy LLC

MarkWest Energy Partners is engaged in the gathering, transmission and processing of natural gas and the transportation, fractionation and storage of natural gas liquids. The company processes gas from the Appalachian Basin and Michigan. Through several acquisitions completed during 2003 and 2004, the company has also expanded the geographic coverage of its natural gas gathering, processing and transmission to the southwest United States. In addition, one of its acquisitions in Michigan has allowed the company to enter into the crude oil transportation business. MarkWest Energy Partners is a publicly owned company. Its shares are listed on the American Stock Exchange under the ticker symbol MWE. The company is headquartered in Englewood, Colo.

Questar Exploration & Production specializes in the acquisition, production and development of natural gas and oil assets. The company operates in Rocky Mountain and the Midcontinent regions. It has development drilling locations in western Wyoming and eastern Utah. The company has been in operation for more than 80 years. Questar Exploration & Production also conducts exploratory drilling programs. The company has over 30,000 acres of lease rights in northwestern Louisiana. It has division offices in Denver, Oklahoma city and Tulsa in Oklahoma. Questar Exploration & Production is a part of Questar Corporation, which specializes in the distribution of natural gas.