by Karen Lee Scott
Staff Writer

Although investigators originally thought it was brick mortar that interfered with a chemical agent monitor at the Tooele Chemical Agent Disposal Facility (TOCDF), further evaluation pegged the source of the disturbance as a portable light and extension cord.

On July 17, when a monitor at the incineration facility detected a substance with characteristics of VX nerve agent, officials halted chemical agent destruction processes and notified both the Deseret Chemical Depot emergency operations center and the Tooele County Emergency Management team. Workers then began running a series of tests to determine if VX agent was really present.

Tests for the agent came back negative so workers knew that something else had triggered the alarm.

At first the “interferent” was suspected to be coming from mortar used between bricks inside of a liquid incinerator. The incinerator had just been re-bricked a week before the alarm sounded and the mortar used was different than what had been used in the past.

However, once the incinerator had cooled (three days later) all signs of interference disappeared from the plant’s chemical agent monitors.

After consultation with experts at the Centers for Disease Control and Prevention and Utah regulatory officials, the decision was made to resume operations while the evaluation continued to investigate the interferent source. The plant resumed operations July 21 using the remaining three furnaces.

After cooling, the problem incinerator was opened and the charred remains of a portable light and its electrical cord were found.

It is suspected that the contractor who did the recent brick work left the light inside the burner. TOCDF laboratory personnel are in the process of recovering and testing the remains of the light as the most likely source of the interferent.

e-mail: kscott@tooeletranscript.com