After I ran photos of the cement plant quarry yesterday, reader Keith Robinson sent me this sequence of photos of the caverns being blasted. He annotated my1966 aerial to show where the blast was centered.
You can see to the right of the “box” the narrow wall that divided the “Blue Hole” from the main quarry. Keith said family friend Burl Medlock made it possible for him to take the photos.
He said the blast used 300 tons of explosives and loosened 1.5 million tons of rock. The surface area was estimated at 6 acres and was up to 200 feet deep. Here’s The Missourian’s version of the blast.
Keith’s photo gallery of the explosion
Click on any photo to make it larger, then use your arrow keys to move through the gallery.
Minor correction, I stated that it loosed 1.5 million tons of rock.
Keith, I’ll change 15 million to 1.5 million in the copy. Thanks.
Another interesting tidbit; the blast destroyed a six million dollar rock crusher that was located in the bottom of the quarry. The rock face expanded more than expected and engulfed the crusher. I was told that the cost of the crusher was insignificant in light of the profit from the cement that would be produced with the rock released in that one blast and how well it was broken up.
To add to Keith’s comments with some more detail. The explosive used was Dupont Tovex. A “jelly” that you could squirt out and put a torch to and it wouldn’t burn. Very high tech at the time, and now a staple of quarry blasting.
The crusher at the bottom of the quarry wasn’t the only thing that got engulfed. A control building for the conveyor that went from the quarry up to the plant itself was taken out as well. But, as Keith pointed out, the rock fractured enough that a couple crushing steps could be taken out of the process which saved much more money than the cost of the lost equipment.
Once in a while Dad would have to check on something on a Sunday morning after Church, so we would ride down to the plant. It was on one of these times Dad took us into the quarry and into the caverns as there was no work activity. We didn’t get out of the car or go in the caverns very far but it was a neat experience. The ceilings were very high.
Scott, I assume Burl was your Dad. As I recall he was the General Foreman of the plant. He was always nice to us when we visited the plant. I haven’t been to the plant since Pop retired in 1982.
My grandfather, Henry Niederkorn, was part of the detonation team. He used to tell stories about this event but I more or less didn’t believe him until I came across Fred Lynch’s blog entry, and in the group photo, Grandpa is the first person on the left. Thanks for adding more dimension to this event, Ken.
I guess your grandfather had a blast at the event.
Would love to hear more about the stories he told you! I bet that was pretty exciting growing up.