Though most famously run by former Vice President Dick Cheney, Halliburton Energy Services was run by Thomas H. Cruikshank during the 80s and early 90s.  What was their primary area of operation?
Halliburton The Halliburton Company, an American multinational corporation. One of the world's largest oil field service companies, it has operations in more than 70 countries. It owns hundreds of subsidiaries, affiliates, branches, brands, and divisions worldwide and employs approximately 50,000 people.
Valero Energy Valero Energy Corporation is a Fortune 500 international manufacturer and marketer of transportation fuels, other petrochemical products, and power. It is headquartered in San Antonio, Texas, United States. The company owns and operates 16 refineries throughout the United States, Canada, United Kingdom, and the Caribbean with a combined throughput capacity of approximately 3 Moilbbl per day, 11 ethanol plants with a combined production capacity of 1.2 e9USgal per year, and a 50-megawatt wind farm. Before the 2013 spinoff of CST Brands, Valero was one of the United States' largest retail operators with approximately 6,800 retail and branded wholesale outlets in the United States, Canada, United Kingdom, and the Caribbean under the Valero, Diamond Shamrock, Shamrock, Ultramar, Beacon, and Texaco brands.