Because LNG is stored at such low temperatures in liquid form, it does not explode. However, it does burn at extremely high temperatures. Once started, a gas fire cannot be extinguished; it has to burn itself out. In a report released by Sandia National Laboratory in December 2004, scientists determined that should a large LNG spill on water be ignited, it would burn at 3000 degrees Fahrenheit for 30 minutes to an hour, throwing off enough heat to incinerate everything within four-tenths of a mile of the vessel. This includes steel, which melts at 2300 degrees Fahrenheit and has no strength left if it is exposed to a temperature of 1200 degrees for 10 minutes. Beyond that range, the threat to most buildings would be from secondary explosions of hazardous materials within the area of the original fire or the result of failed efforts by firefighters to contain it. Even in protective clothing, firefighters could get no nearer than 1.3 miles away from the fire until it started to burn itself out. Those people outside this range but within the second-mile radius of the fire would suffer second-degree burns on unprotected skin within about 30 seconds. However, most would likely be able to get to shelter and avoid this exposure.
On the West Coast, Nabih made the decision to keep his operation simpler, using only his comrade and one Zodiac. His target would not be escorted. His plan was to attack the oil tanker towards the rear of the ship just as it cleared the harbor breakwater. If things worked out as planned, he would be able both to set the vessel on fire and to cause enough damage to the vessel to make it unmaneuverable, so that it would ultimately sink in the channel.
Early one Friday morning before the Labor Day weekend, two boat trailers arrived at the boat ramp in Mary O’Malley Park on the Mystic River Reservation, just a few miles north of the Everett facility. Khalid and his four colleagues brought along fishing poles, bait, and a cooler. The IED had been loaded into the boat and covered with a blue tarp. Their destination was a marina just south and west of the Tobin Bridge, a short distance from the Charlestown Navy Yard, where the USS Constitution was moored. To buy themselves some time, they purchased some ice for their supposed fishing trip. Meanwhile, on the opposite coast, an SUV backed a Zodiac down the Cabrillo Beach boat ramp in San Pedro, California. After parking the vehicle, Nabih and his accomplice headed out toward the breakwater at the entrance of Los Angeles Harbor.
It was just before 10 am when the LNG tanker Matthew — ironically, the very vessel that had been stranded outside Boston Harbor after 9/11 — steamed past the runways of Logan Airport and turned north for the final two miles of its voyage to the Everett facility. There were Coast Guard vessels in front and along either side of the tanker. When the ship reached Boston’s North End, the harbor narrowed to about 750 feet across.
Khalid waited until the Matthew was making its final turn to transit under the bridge. The two Zodiacs then darted out from the Shipyard Quarters Marina. By the time the Coast Guard vessel on the port side of the Matthew saw them, the Zodiacs were moving at full speed only 250 feet away. The petty officer in charge of the escort vessel reached for his bullhorn to warn the boats to steer clear. That cost him precious time. By the time he realized that the Zodiacs were heading directly for the LNG tanker, it was too late. The Zodiacs drew alongside the tanker, roughly 150 feet apart. As the Coast Guard scrambled to remove the safeties on their weapons, a man stood up in each boat and pressed an object to the hull, then disappeared in a blinding light.
Soon there was a torrent of liquefied gas spilling out of two gaping holes in the tanker’s hull. As the gas came into contact with the warm air outside, it started to vaporize, and then the vapors ignited.
On the West Coast, Nabih’s Zodiac arrived at the breakwater shortly before 6 am, West Coast time. As planned, they traveled eastward, staying close to the inside of the breakwater, and then intercepted the 300,000-ton Panamanian-flag vessel Mercury Glory as it was entering the Long Beach channel. As the Zodiac approached the vessel, Nabih gave a friendly wave. Then the Zodiac suddenly turned around and drew alongside the rear of the vessel. Nabih stood up, held the EFP against the hull, and set off the detonator.