Destroying a deadly nerve agent stockpiled in western Indiana could take a lot longer than the Army originally anticipated, military officials said.

A projection of 2 1/2 years for chemically neutralizing the Newport Chemical Depot's (search) VX nerve agent (search) was based on a rate of 2 1/2 hours for each batch of the nerve agent to reach a set VX nondetect level. But tests conducted at Army laboratories in Edgewood, Md., found that about half of the stockpile contains a chemical stabilizer that takes 10 to 16 hours to reach that nondetect level, said Jeff Brubaker, the Army's site manager.

He said analyses of samples taken from Newport's 1,269 tons of VX, show that 46 percent of the stockpile contains a stabilizing agent called DIC and that those batches can be neutralized within 2 1/2 hours to the nondetect level.

However, the remaining 54 percent contains either a stabilizer called DCC, or a DIC-DCC blend. Those batches take far longer to reach the nondetect level of no more than 20 parts per billion of VX, Brubaker said.

"The difference, as it applies to the neutralization process, is that it may be necessary to process the DCC or DCC-DIC blended stock for longer periods," he said. "This factor has the potential to extend our schedule for destroying the entire Newport stockpile, but should not affect our ability to begin destruction operations."

Brubaker said the tests performed with DCC and mixed stabilizers were at laboratory scale, using a 0.8-gallon reactor, and that it is not easy to duplicate the mixing provided by larger and more sophisticated reactors.

Tests done in 1999 using a 100-gallon chemical reactor comparable to the newly built reactors at Newport that will be used to destroy the VX suggested that longer processing times will not be needed, he said.

"However, until we use the actual reactors in the plant, which we know perform differently from the smaller laboratory equipment we have been using for verification, we cannot rule out longer processing times," he told the Tribune-Star of Terre Haute.

The Army wants to ship about 4 million gallons of the VX byproduct — a chemical called hydrolysate that has been compared to liquid drain cleaner — to a DuPont Inc. plant in New Jersey. Under those plans, DuPont would dump the treated hydrolysate into the Delaware River.

The VX destruction at the depot about 30 miles north of Terre Haute cannot begin until the federal Centers for Disease Control and Prevention (search) concludes its review of the project. The agency is also reviewing the Army's plans to ship the hydrolysate to New Jersey for processing and disposal.

Army officials said last month that they have pushed back until late this year the expected start of the project to destroy the VX — a mineral oil-like liquid that can kill a healthy adult male with a single pinpoint droplet. The work had been expected to start this summer.

Meanwhile, work continues to address safety issues raised by two teams of government officials who witnessed July tests at the sprawling complex built to destroy the stockpile.

Army spokeswoman Terry Arthur said that as of Tuesday, 54 issues remained of the 190 items raised in the safety review. The depot expects to submit its report on how 51 of those matters have been handled by the end of this week, she said.

"Work is under way to complete the remaining three recommendations by the end of this month," Arthur said.