Small amounts of unstable, potentially explosive chemicals discovered at Solvay on King Street Extension are in an on-site, stand-alone building away from the plant production area, state regulators said Monday.

"Should a chemical reaction inside the bottles be touched off, the reaction would cause damage to the lab hood and surrounding (inside) area. We believe such a reaction would not be strong enough to cause any structural damage to the building or endanger the operations of the facility," said Jim Beasley, spokesman for the state Department of Health and Environmental Control.

The discovery of 10 grams of crystallized picric acid and 20 grams of crystallized 1,3,5-Trinitrobenzene prompted Solvay to request an "emergency" permit from DHEC to hire a contractor to neutralize and dispose of the substances, which are in separate bottles.

"They are not really emergency permits. They are temporary permits," said Charles Tuskan, plant manager.

The chemicals, which are no longer needed for plant operations, were discovered during housekeeping-type organizational activities, Tuskan said.

"We decided it was time to go through some of the lab bottles," he said.

Solvay is not authorized to dispose of the chemicals it found in the two bottles, so it sought the DHEC permit, he said.

"We know that this poses no risk to the public," Tuskan said. "It really doesn't pose any risk to the workers."

The chemicals were found during the cleaning-out of a lab hood, which is a standard piece of safety equipment used for working with hazardous substances, DHEC said.

Tuskan said he was not sure what process a contractor would use to neutralize the chemicals for safe transport. That is expected to happen on or before May 1, he said.

The bottles are currently being kept in a locked lab hood, DHEC said.

"These chemicals cannot be safely transported in their current state. They must be treated on-site so they can be neutralized and transported to an appropriate site for disposal," Beasley said by email.

The company requested the DHEC permit in a March 18 letter, and it was issued on April 7. The first public notice about the situation was issued Thursday.

Solvay's Charleston plant, located along the Ashley River, produces ingredients for flame retardants, water treatment, pharmaceuticals and agricultural applications.

Reach Prentiss Findlay at 937-5711.