‘Last Blast’ for MMIII Missile Silos

December 17, 2024

This article originally appeared in the Jan/Feb 2002 issue of DEMOLITION magazine.

Many of us remember all too well the tensions between the United States and the former Soviet Union that led to an all-out arms race in the 1960s and 1970s. Both countries built thousands of missiles and equipped them with nuclear warheads to defend themselves. Many of those missiles were lowered into deep concrete silos below ground, such as the Minuteman III (MMMIII) Intercontinental Ballistic Missiles in northeastern North Dakota.

On Aug. 24, the MMIII program in Grand Forks, North Dakota, ended with a thundering blast, huge chunks of concrete and steel flying high into an overcast sky, and a large plume of gray dust and smoke.

That morning, H-22, a MMIII missile silo near Petersburg, North Dakota, was dramatically destroyed in just seconds by Veit & Company, an NDA member, bringing an end to an era that most people hope will never happen again. It was the 149th and last MMIII silo implosion performed by the company.

Veit & Company of Rogers, Minnesota, is completing a $13-million contract that originally called for the dismantlement of 150 MMIII silos or launch facilities (LF) and permanently sealing 15 launch control facilities. However, the 150th and last LF in the area, along with the 15th and last LCF, will now remain intact and preserved by the North Dakota State Historical Society.

Last of the ‘Last Blasts’

Over 500 people watched the “last blast,” as the implosion of H-22 was called, including high-ranking Air Force personnel, special guests, news media from around the world and ordinary citizens who lined the gravel roads surrounding the site. Ground zero was on farmland approximately 50 miles west of Grand Forks.

“This is a momentous occasion,” said U.S. Air Force Brig. Gen. Gregory Pavlovich, himself a former missile wing commander, who hosted a ceremony before the implosion. “With this event, our nation falls under the limits imposed by the Strategic Arms Reduction Treaty. But it’s also a sad day for the ICBM force and for the Air Force as we watch this event with mixed emotions.

“We get nostalgic about the great things that we (the missile forces) have accomplished as a team, but times change, and we must change with them. It is indeed our privilege to witness this landmark event in the fact that there are decreased tensions in the world. We kept the faith and ended the Cold War on our terms, and we are adjusting to meeting the needs of our beloved nation for peace in the world.”

Maj. Dave Rundell, commander of the USAF’s 39th Air Refueling Wing intelligence flight and a former member of the 321st Missile Wing, watched the historic implosion and reminded everyone to remember why having the missiles were so important to the nation’s national security. “They provided an almost immediate response to a potential attack against the United States, and since the readiness rate was virtually 100%, they were an extremely reliable deterrent option,” he said.

Loren Nishek, Veit’s operations manager for North Dakota, said the last implosion went flawlessly. “It was an excellent implosion,” he said. “Everything went well and on schedule.”

Fire in the Hole

The first MMIII silo implosion at the Grand Forks missile complex took place on Oct. 6, 1999, near Langdon, North Dakota. That year, 13 more MMIII silos were imploded, 86 in 2002, and 49 this year. “We’ve gone through a lot of adverse conditions with all of these implosions, but we got the job done safely and ahead of schedule,” Nishek said.

Prior to the implosion, an extensive grid work of holes about 2 inches in diameter was drilled to depths of 30 feet around the perimeter of the silo. About an hour before detonation, Nishek and company began loading the explosives, beginning with a stick of dynamite in each hole. Before lowering each stick into a hole, a non-electronic cap and lead wire were inserted into the dynamite. Next, each hole was filled within 3 feet of the surface with ANFO (ammonium nitrate and fuel oil), followed by gravel to the top of the hole. A number of holes also received additional dynamite called pre-split, which looks like a string of large sausage links.

All of the lead wires were quickly connected with squeeze-on connectors to the detonation cable. An electric wire was then strung about 2,000 feet across a grassy field to the viewing area and connected to a special panel built by Veit that allowed a number of dignitaries to take turns in pressing buttons in a detonation sequence.

Observation and Verification

More than 20 members of the media witnesses the event, including representatives from Reuters News Service, British Broadcasting Company, American Broadcasting Company, National Broadcasting Company and the Columbia Broadcasting Service. An estimated crowd of 500 spectators also watched, including retired farmer Leonard Berdal of Petersburg who owns land less than a mile from H-22.

“I lived here all my life and farmed this land around where the silos were built,” Berdal said. “The cables for the missile silos ran through my land and coming into this implosion was something I wanted to see because it was the last time to see it.”

The MMIII LF demolitions and dismantlement of the LCFs were part of the Strategic Arms Reduction Treaty I (START) of 1991, which actually entered into force late in 1994, according to Master Sgt. Jeffrey Schlesinger of the 319th Air Refueling Wing treaty compliance office. Besides the USA and Russia, he said that START I is in force with Belarus, Kazakhstan and Ukraine.

“Once the contractor (Veit) gets the site to a point where it is ready to go into observation status, we have to send a notification to the State Department, which translates and sends it to the Commonwealth of Independent States,” Schlesinger continued. “Once the notification is sent out and all parties are notified, the site goes into observation status for 90 days.”

Prep and Salvage

Veit & Company, headquartered in Rogers, Minnesota, was contracted to perform the demolition for the entire project. Tech. Sgt. Stever Marback, who has worked with Veit answering any technical questions they had since they started the project, said they’ve done a great job up to this point in doing the implosions. “They’ve gone without a hitch,” Marback said. “They’ve done it safely, and I think the end result has been and will be fantastic.”

Like all previous MMIII demos, Veit and its partner subcontractors actually began the demolition of H-22 several weeks prior to the implosions by pushing back a 108-ton reinforced concrete lid that covered the silo.

Each silo measured 30 feet in diameter for 30 feet below grade, at which point it narrowed to 12 feet in diameter and continued down for another 60 feet. The adjacent Launch Equipment Building is buried 30 feet deep with two 30-inch diameter vent shafts, many concrete markers, light poles, antennas and other structures.

H-22 and each of the other MMIII LF sites are approximately 13 acres in size, including ground zero, a 1.5-acre section that’s surrounded by an 8-foot-high chain-link fence where the silo itself was constructed. The pre-implosion process for each silo involved removing tons of steel silo liner and steel from the catwalk, large aluminum cabinets, copper wiring, aluminum, brass, electrical switches and other materials. After the blast, another ton of rebar was salvaged, while the concrete silo itself was reduced to rubble and used to fill the hole.

A 4,000-gallon, fiberglass shallow tank for diesel fuel that was used for standby generators also had to be drained and removed from H-22 before the blast. All told, 136 MMIII silos had this type of tank, while an 11,000-gallon diesel fuel tank was drained and abandoned in place at 14 of the silos. Each missile LF also required the abandonment of a cathodic protection well.

Each 20-acre LCF included 4.25 acres, also enclosed by an 8-foot-high chain-link fence. Inside the fenced area were a garage and control building that housed support personnel and equipment. Sixty feet below the control building were two large, highly fortified capsules that were accessible by a service elevator. The capsules were used to house communications and operations equipment, and personnel to launch 10 MMIII missiles.

The dismantling and sealing of each LCF involved draining and abandonment or removal of three to six diesel storage tanks, a cathodic protection well, salvaging all recyclable materials, filling and capping the elevator shaft, and abandonment of a sewage lagoon. Partner contractors who assisted Veit with the silos and LCFs included R&N Hide & Fure of Hettinger, North Dakota, for salvage operations, and Town and Country Drilling of Mandan, North Dakota, for abandonment of cathodic protection and water wells. North Star Environmental of Chetek, Wisconsin, removed or abandoned storage tanks, while Pro-Source Technologies of Coon Rapids, Minnesota, handled environmental testing.

Building on Success

Other recent, major demolition projects by Veit & Company include the St. Paul Civic Center for the new Xcel Arena, home of the Minnesota Wild hockey team; Stroh’s Brewery and Malt House, the eight-story old Minnegasco Building and seven-story Minneapolis Conservatory, both in downtown Minneapolis; the Mets Sports Center in Bloomington; and Memorial Stadium on the U of M campus. Veit & Company also handled the excavation and site preparation for the expansion of the Minneapolis Convention Center and is currently involved in the initial construction of portals for the new Light Rail Transit System.