News_FireInTheHole

The lever, he explained, was attached to a spring inside the tube. In one minute, when I was to pull the lever back and release it like a slingshot, a stainless steel rod inside would slam forward against a small brass primer mounted at the end. That primer, which was about the size of a pencil eraser, would ignite about 200 feet of neon yellow cord that led from the end of the pipe to more than a dozen holes drilled 50 feet into the soil and topped off with a total of 16,000 pounds of explosives.

"Fire in the hole! Fire in the hole! Fire in the hole!" Lopes, the quarry's official blaster, spoke into his radio.

Quarry Manager Steve Long finalized plans for the blast more than a week before I showed up. He had ordered explosives from Alpha Explosives and let others around the quarry know how big a chunk of South Hill needed to come down.

When I showed up the day of the blast, Long drove us to the top of the 275-foot hill to watch Lopes and a worker from Alpha Explosives mix ammonium nitrate fertilizer with diesel fuel to create the ANFO mixture. Timothy McVeigh used about 3,000 pounds of ANFO on the Oklahoma City Federal Building - roughly a fifth of what Long planned to shoot.

Long and I drove around while Lopes finished loading, then we headed back up to the top of South Hill at 11:15 a.m. Everything was tied off at the blast site, and the lone piece of yellow cord ran from there back to a big white drilling rig we would use for shelter.

With one minute to go, Long and Lopes radioed throughout the mine that we were approaching blast time. After Lopes issued his three "fire in the hole" commands, he counted down from 10 to 1 and signaled me with his hand.

The metal rod clicked forward, I startled at the loud "crack" emitted by the primer and the entire hilltop in front of us leaped several feet in the air.

Lopes wanted to know if I had noticed the quick, bright flash inside the length of cord. The brass primer had ignited a fine micro-explosive inside the hollow cord, and the ensuing explosion traveled inside each hole to set off the ammonium nitrate.

"That shock wave travels 6,500 feet a second," Lopes said. "When there's fog out here you can really see it light up."

We approached the smoking heap. The dirt was still solid as we walked along and then, abruptly, it looked like a photo from the 1906 earthquake: a four-foot crevice separated where I stood on solid ground and huge chunks of busted ground.

Peering over the edge, the result looked like an avalanche, with boulders and rocks spread evenly down a 60-foot drop. Fifty-thousand tons of solid rock pulverized just like that.

Long said that, in a 10-hour day, trucks and loaders would muck out about 3,000 tons of rock. At that rate, he said, it would take them 15 to 20 days to haul out everything we just shot.

"All clear on South Hill," Lopes announced into his radio.

Contact:
Aimi Dutra
Dutra Group
Phone: (415) 458-5473
Email: adutra@dutragroup.com