Salt Lake Tribune
TUESDAY July 29, 2003

Trial begins for chemical depot supervisor

By Pamela Manson
The Salt Lake Tribune

At the Deseret Chemical Depot in Tooele, employees researching ways to dispose of the nation's arsenal of chemical weapons rely on gas masks and air monitoring tests to keep them safe.

But a supervisor at the facility put workers in danger last summer when he falsified the results of tests done to show whether air monitoring units were performing at passing levels, a prosecutor claimed Monday at the opening of the trial of David James Yarbrough, of Stockton, who faces eight counts of making false statements to a government agency.

"The defendant cheated the system at the expense of safety," Assistant U.S. Attorney Mark Hirata said.

But defense attorney Earl Xaiz told jurors that Yarbrough did not make any false statements or conceal test results. His client believed he was following regulations as he performed the complicated, technical procedures to verify that the testing units were functioning at a level that would ensure worker safety.

Xaiz said Yarbrough devised his own data sheets to compile as much information as possible on the air monitoring system and correctly recorded all figures that he was given.

"The government has it wrong, absolutely wrong," Xaiz said of the charges.

He added, "Why would he endanger his own safety," pointing out that Yarbrough worked in the area where the air was being monitored for nerve gas and other chemical agents.

The charges against Yarbrough, a worker at the Oquirrh Mountain Facility Plant at the depot in Tooele, concern baseline tests that are performed to ensure that air monitoring machines are working properly. The machine's units set off an alarm to warn employees of any unexpected release of toxic air.

The depot suspended operations in August at Oquirrh because of inconsistencies found in the results of baseline tests supervised by Yarbrough, a civilian employee who has worked at the depot for more than 20 years, including nine as a division chief at the plant. Prosecutors claim the inconsistences resulted from Yarbrough omitting data or misreporting test numbers so the monitoring units falsely appeared to pass the baseline test.

Yarbrough, who was assigned other duties after being indicted last fall, has maintained his innocence. The charges against him carry a maximum term of 5 years each.

The trial, being held before Judge Tena Campbell of U.S. District Court in Salt Lake City, resumes today.