Although the ongoing boom in natural gas is unprecedented, Seal Beach-based Clean Energy Fuels, Corp. had long provided facilities in anticipation of increased natural gas use. As a result, the company is poised to make its first profit since the venture was founded by T. Boone Pickens in 1997. The company currently provides fueling facilities for Metro, which runs an all-natural gas fleet. However, Clean Energy expects increased business from private industry customers who continue adding natural gas engines to their fleets. However, analysts conclude that its success will depend on how the energy fueling concern will weather competition from cleaner, low-sulfur diesel, which continues to fuel the vast majority of fleets across the nation.