Before a new Tooele Army Depot plant begins destroying chemical arms, another plant on Johnston Atoll in the Pacific is supposed to work out all the bugs with the process.

The trouble is that Johnston Atoll has had more bugs and delays than expected, and a new government report says its recent start-up of testing was 34 months behind the original schedule.But the Army has continued to build its new plant at Tooele anyway, without waiting for lessons learned at Johnston Atoll before finishing design and beginning construction.

Army officials insist the situation still will not compromise safety at Tooele because they will still make changes as needed - but changing a building instead of just blueprints may increase the $70 million price tag of the new chemical arms destruction plant at the depot's South area in Rush Valley.

"Because of a tight schedule to destroy the stockpile and the large number of chemical arms stored at Tooele, construction began there before the test phase at Johnston Island could be finished (or even started)," said Marilyn Tischbin, spokeswoman for the program manager for chemical demilitarization, based at Aberdeen Proving Ground, Md.

"The biggest difference now is we plan to transfer each lesson learned from Johnston immediately, instead of waiting for the whole test period to be completed as we will before designing some of the other plants," she said.

"It may significantly increase costs because you are changing equipment or a floor or a wall, instead of just a drawing," she added.

The Army is racing to meet a December 1998 deadline to destroy all the aging chemical arms it has stored at eight sites in the continental United States.

Tooele stores 42 percent of them and had to start construction earlier than other sites to meet that deadline. The Tooele plant is scheduled to begin operations in October 1993.

But the Army has already convinced Congress to move the deadline back twice.

Congress in 1985 passed a law ordering 90 percent of the stockpile be destroyed by 1994 and began a program to replace the weapons with safer, more modern arms. When the Army said it could not meet that deadline, itwas pushed back to April 30, 1997. That was pushed back again this year.

The U.S. General Accounting Office released a report earlier this month revealing that by the time Johnston Atoll began a scheduled 18-month test period of arms destruction this summer, it was 34 months behind the original schedule.

The report said the reasons included the plant being redesigned to handle all types of chemical arms instead of just 155-mm rockets; the contractor having trouble finding people willing to work on the tiny, remote island; salt water causing extensive corrosion; and technical problems with much of the machinery - including such things as discovering arms had to be shredded into smaller segments than planned to incinerate them.

The Johnston Atoll plant is seeking to further refine a destruction process pioneered at a pilot plant at Tooele. As the Deseret News revealed last year, the pilot plant had eight accidents with deadly nerve gas that released up to eight times the legal hourly limit.