NEWPORT, Ind. — An Army contractor resumed work Monday to destroy a deadly nerve agent after pausing for nearly two weeks to replace degraded seals in a reactor used in the process.

Workers discovered the degraded seals May 18 in a three-way valve in one of Newport Chemical Depot’s two reactors, prompting the shutdown of both reactors used to destroy the western Indiana complex’s VX nerve agent.

The Cold War-era agent is so potent a single drop can kill a person.

On Monday, chemical neutralization of the VX resumed in Reactor No. 1 after the three-way valve system was tested, said Jeff Brubaker, the Army’s site project manager.

Operations will resume in the other reactor after it is tested, he added.

“When we face challenges, we stop work, assess and correct the situation if necessary, then move forward,” said Rick Rife, project manager for contractor Parsons Technology Inc.

The project, scheduled to be complete by the end of 2007, is expected to produce as much as 4 million gallons of caustic wastewater, which the Army wants to ship to a DuPont Co. plant in New Jersey for final treatment and discharge into the Delaware River.

Since VX destruction began in 2005, workers have destroyed about 15 percent of the more than 250,000 gallons of it stored at the complex, about 65 miles west of Indianapolis.