The group's principal activities are to develop, explore and produce crude oil and natural gas. It participates in various joint ventures for the purpose of acquiring and developing oil and gas properties. The group operates solely in the domestic market. The pemc provides administration, accounting and tax preparation services for limited partnerships and trusts. The socc and eowsc perform oil and gas field servicing. The poc is an operator for producing oil and gas properties of the group and its affiliates. The major customers of the group include texon distributing lp, unimark llc and plains all America inc.