On January 16, 2006, at 0905 mountain standard time, a Boeing 737-524, operated by Continental Airlines as flight 1515, was parked at the gate in preparation for departure from El Paso International Airport, El Paso, Texas. The flight's intended destination was Houston, Texas, with a crew composed by a captain, first officer, 3 flight attendants, and 114 passengers all reported on board. During the preflight inspection conducted by the first officer, a puddle of fluid was noticed on the tarmac under the right engine. Both the captain and the first officer re-inspected the puddle of fluid under the right engine and agreed that it appeared to be an oil leak. The captain notified Continental El Paso Operations via radio from the cockpit to request authorization for contract maintenance to check for problems on the right engine. Continental El Paso Operations contacted Continental Headquarters Maintenance Control and received authorization for contract maintenance to respond to the aircraft based on the captain's report. Three mechanics from Julie's Aircraft Services, Inc., a fixed based operation at the airport, arrived at the airplane and began to investigate the source of the reported oil leak. Both sides of the right engine fan cowl panels were opened for inspection, and the mechanics requested that the captain conduct an engine run to check for the oil leak.