One quarter of all the mustard agent stored in old Cold War-era weapons at the Pueblo Chemical Depot has now been destroyed, officials announced this week.

The weapons — old 155 mm and 105 mm howitzer shells, plus mortar rounds — are being dismantled and destroyed at the Pueblo Chemical Agent-Destruction Pilot Plant and Army officials announced this week that 112,400 of the 155 mm rounds have been destroyed.

They contained more than 600 tons of mustard agent, roughly one-quarter of all the mustard agent that is stored at the depot in old munitions.

“With the destruction of each 155 mm munition, we also eliminate 11.7 pounds of mustard agent,” said Walton Levi, the acting site project manager, in a statement this week.

He said the total mustard agent destroyed was a quarter of the 2,600 tons stored at the Pueblo depot.

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