On Aug. 4, Beirut experienced tremendous death and destruction when a notoriously dangerous cargo caught fire and exploded in the seaport. According to investigators, the cause of the devastation was 2,700 tons of ammonium nitrate stored in a port warehouse.

The commodity arrived at the Port of Beirut in 2013 from the country of Georgia on board the bulk ship Rhosus. While it was destined for Mozambique for use as fertilizer, Lebanese authorities seized the financially troubled vessel and removed its cargo to storage.

The devastating explosion that claimed the lives of more than 200 people and injured thousands across Beirut is yet another unfortunate reminder of ammonium nitrate’s long and troubled history.

In the U.S., ammonium nitrate was the main ingredient for the terrorist bombings in 1993 at New York’s World Trade Center and 1995 at Oklahoma City. However, one of most deadly American disasters involving this commodity occurred at the port of Texas City, Texas, in 1947.

At the end of World War II, much of the U.S. government’s stockpile of ammonium nitrate was converted to nitrogen-rich fertilizer and shipped in the form of aid to recovering farms in Europe.

By early 1947, more than 80,000 tons of ammonium nitrate passed through Texas City from Army ordnance depots in Iowa and Nebraska where it had been used as a major ingredient in making bombs. The gritty substance was considered nonexplosive and almost impossible to burn, but under heat, confinement and pressure it became highly volatile.

On April 16, 1947, smoke was seen spiraling from the ammonium nitrate cargo on board the French liberty ship Grandcamp, which was berthed at the Texas City Terminal Railway facility. A fatal mistake was made — one that would lead to the nation’s worst industrial catastrophe.

Firefighters poured water onto the area of the shipboard fire, but its effect was negligible. Fire extinguishers and the continued spray of water from fire hoses still failed to contain the blaze.

The failure of these extinguishing methods caused the Grandcamp’s captain to dog down and tarpaulin the hatch covers. The ship’s ventilators were plugged, while a steam-injection system activated. Normally, steam might have extinguished the fire of 2,300 tons of powdery cargo packed in 46,000 paper sacks.

But the fire continued to spread in the sealed holds of the Grandcamp, causing heat and pressure to build, effectively turning the ship into a steel pressure cooker without a safety valve.

Unaware of the worsening conditions, other ships continued to load nearby. The C2-type cargo ship High Flyer, of Lykes Lines, was loading boxcars for the French railways atop its already loaded cargo of ammonium nitrate and sulphur. Another liberty ship, the Wilson B. Keene, was loading flour and rice. Other industries at the Texas City port included three oil refineries, chemical plants and tank farms holding petroleum and chemical products.

When the general fire call was issued to the city fire brigade and tugs from Galveston were ordered to stand by, time was already running out at Texas City. By 9 a.m., the hatch covers of the Grandcamp were straining against their clips and the tarps were smoldering. Firefighters could feel fearsome trembling as molten nitrate came to a high-pressure boil.

Suddenly, the ship’s hatch covers blew off in a fountain of golden smoke, and flaming sacks spewed high over the vessel onto the warehouse, the High Flyer and other ships. Water hoses were run out and the ships would be towed away if the situation worsened.

Smoke boiling from the Grandcamp turned dark red and the flames and heat caused firefighters to rush to the pier. White balls of fire rocketed from gaping holes in the No. 4 hold from which sounds like a blast furnace emanated and water hissed down the sides of the red-hot hull.

At 9:12 a.m., the Grandcamp blew up and everything around the ship vanished in a roar of flames. A mushroom-shaped cloud of molten iron, blazing nitrate and other cargoes of cotton, nuts, ammunition and drilling equipment were thrown thousands of feet into the air and rained down upon the city. Chemical plants and refineries were engulfed. The blast was felt 150 miles away and earthquake seismograph needles jumped more than 1,000 miles away. More than 600 people died and thousands were injured.

Eight hours after the blast, there was a glimmer of hope that the worst was over. At 6 p.m., the High Flyer was still burning and a stench of its sulfur cargo permeated the waterfront. The city was evacuated and as the tugs began to tow the ship away from docks, fireballs shot up into the sky and a blazing orange glare indicated the High Flyer had ceased to exist. The largest piece of the vessel — its turbine — was found a mile away. Fires continued to burn at Texas City for more than a week.

Subsequently, changes were made in the ammonium nitrate manufacturing process and new regulations were imposed on the handling and shipment of this substance. One would have hoped the Lebanese port authority had exercised better stewardship of this cargo, which laid in a warehouse for the past six years. However, it seems we rarely learn from history.

Click for more Maritime History Notes by Capt. James McNamara.

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