Dykon’s main man explains the methods he’ll use to fell 250 metre stack.
When the two tallest Asarco stacks are demolished within seconds of each other early next year, old-time dynamite will bring them down. There is historical symmetry in the use of dynamite. At the turn of the century, when the plant was built, dynamite was replacing nitroglycerine as a safer tool for mining raw materials processed by the smelters. Over time, the plant’s furnaces purified copper, lead and other materials blasted from the Earth’s crust.
“It’s (dynamite) still the best workhorse in the industry,” said Jim Redyke, president of Dykon, the explosive demolition company hired to bring the stacks down. Redyke’s Tulsa, Okla.-based company has used explosives to bring down numerous structures in Texas, including Texas Stadium, and around the world, including a 900-foot smokestack in South Africa, which the company bills as the world’s “tallest stack shot.”
“I’ve done hundreds of smokestacks,” Redyke said in an interview last week at the Asarco site. Also among those were two “little brick stacks,” one that fell as a car drove under it in the Burt Reynolds movie “Hooper.” “I call that being paid to play,” he said with a smile.
Redyke would not discuss the price, but Roberto Puga, the trustee in charge of the $52 million demolition and cleanup, said it falls within the site’s $8.8 million demolition budget.
The method Redyke will use to bring down the Asarco stacks — the other is about 600 feet tall — is almost exactly like felling a tree, but in reverse, he said.
Hammers are used to chisel out a channel parallel to the ground on the side opposite the direction he wants the stack to fall. That channel provides access to vertical steel rods, called rebar, embedded to strengthen the concrete. Those rods are cut with torches, which will allow the stack to tip over quickly. When the time has come to knock the stack down, explosive charges on the other side are detonated, blowing out a section that begins the fall. Concrete hinges — part of the stack wall on either side of the blown-out section held together by uncut rebar — direct the stack to its intended drop zone.
“Gravity is my friend,” Redyke said.
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