As part of my Apprenticeship in the 60s. I worked at the mine. They used Ammonium Nitrate as the primary explosive and a smaller charge of, I think dynamite to set it off. Coal and other miners considered the Anhydrite mine a underground quarry as it was only 900 ft. deep.
I also visited the anhydrite mine in the 60s and remember talking to one of the expert blasters down there. They were the highest paid men in the mine. I was amazed how they could shape the dynamite charges by drilling into the face in a “V” formation, charging , then blasting with the centre charges going off milliseconds before the outer ones ,leaving a neat rock fall with the right height and width for the draggers to remove it. The roof supports were big columns of remaining rock ,I think 20″ square.So the mine was quite safe for that reason,I was told.
I went down the anhydrite mine on a visit from college in the “60”s. The guide turned off the lights briefly, it made us realise that we”d never been in total darkness before, a really weird sensation. We were told that all the vehicles were taken into the mine in pieces & built up undergound. The guys who worked down there had a canteen for breaks – all in all an amazing place.
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As part of my Apprenticeship in the 60s. I worked at the mine. They used Ammonium Nitrate as the primary explosive and a smaller charge of, I think dynamite to set it off. Coal and other miners considered the Anhydrite mine a underground quarry as it was only 900 ft. deep.
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I also visited the anhydrite mine in the 60s and remember talking to one of the expert blasters down there. They were the highest paid men in the mine. I was amazed how they could shape the dynamite charges by drilling into the face in a “V” formation, charging , then blasting with the centre charges going off milliseconds before the outer ones ,leaving a neat rock fall with the right height and width for the draggers to remove it. The roof supports were big columns of remaining rock ,I think 20″ square.So the mine was quite safe for that reason,I was told.
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I went down the anhydrite mine on a visit from college in the “60”s. The guide turned off the lights briefly, it made us realise that we”d never been in total darkness before, a really weird sensation. We were told that all the vehicles were taken into the mine in pieces & built up undergound. The guys who worked down there had a canteen for breaks – all in all an amazing place.
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