Munitions Experts Explode 3 Shells Found in Ravine Near Rocketdyne

Bomb experts Tuesday exploded three artillery shells found in a ravine at Rocketdyne’s Santa Susana Field Laboratory last week--munitions that company officials described as small and innocuous.

“There were no real surprises,” Rocketdyne spokesman Dan Beck said after the detonations. “Two seemed to have some sort of high explosive in them. The third, the biggest of the three, was inert. It was in effect a dummy round.

“It’s still difficult to say exactly what they were, other than a piece or artillery ordnance of some sort,” Beck said. “The larger was off some sort of rocket, but it was the dummy round.”

The shells were found July 1 as part of an ongoing $55-million cleanup of contamination at the Santa Susana facility. The 2,668-acre open-air field lab, nestled in the hills between the Simi Valley and San Fernando Valley, was the site of decades of nuclear and rocket engine research for the government.

Munitions experts detonated the shells in a bunker with 8-foot-thick reinforced concrete walls at 9:39 a.m., 11:07 a.m. and 1:48 p.m. Buried in sandbags, the shells were exploded by remote control from about 1,250 feet away.

“No one was hurt,” said Beck, who observed the blasts. “No property was damaged. Nothing went awry. The sounds were muffled and not much louder than standing next to a car door when it’s slammed loudly. We had no calls or complaints from neighbors in [nearby] Bell Canyon.”

The blasts were videotaped and overseen by Ventura County fire and sheriff’s officials.

The remains of the shells were scooped up into containers by Rocketdyne and the state toxic substances department for further study. The composition of the three shells won’t be known for two to three weeks, officials said.

“If there is anything in there but filler, my experts say it is probably a small quantity of high explosive, such as TNT,” Beck said. “They do know for sure that it’s not any sort of liquid chemical in there.”

The shells are believed to be remnants of motors for “projectiles, whether rockets, missiles or artillery shells” tested by Rocketdyne in the 1960s, he said.

Rocketdyne officials have consistently described the shells as small and innocuous.

However, documents filed by company officials with the state Department of Toxic Substances Control to obtain an emergency permit speak of the danger they might have posed.

In emergency permit information obtained by The Times, company officials wrote, “Rocketdyne requests this permit to detonate the rounds because they may pose an immediate threat as their stability is not known and may pose a detonation risk. In addition the rounds cannot be transported off-site for disposal. Consequently, the safest way to manage the rounds is to detonate them on site.”