Day 4 Afternoon

After a Heavenly Ham picnic lunch, we headed to SHM which builds and repairs highwall miners. Highwall miners mine 20,000 - 200,000 tons in a month. The machine costs $8 million. An estimated $15 million is needed in total machinery. 200-300 dollars comes from each ton. The machine runs 1000 feet underground and can cut from 28 inches to 15 feet high. If the seam is 30 inches, you might do one or two 1000 foot holes in a day. A wonderful thing about highwall mining is that there are no people underground so there is much less danger than underground mining. Maintenance is constantly being done while the miner is running. The miner might run for 20 years. Underground continuous miners will have about 9 people on a machine to only 3 people needed for a highwall miner. Less people are needed and they must be very computer literate because so much of the opertion is computerized. Young people have no problem running the machines. 12 feet wide is the maximum width cut by a highwall miner, and it must be self supporting roof for the highwall miner to be used. A continuous miner will mine 20 feet wide so it needs beams to hold up the roof. It takes about 22 tractor trailers to move a highwall miner. This was a very interesting experience and I look forward to being sent more information which I can use for my math classes as I teach about functions. I plan to use information about how many tons are mined, to time taken per ton, to costs to run the machine. Together with information about other mining methods, we will eventually use the information for students to debate the pros and cons of different types of mining. There will definitely be issues to debate focused on everything from safety, to impact on the environment, to employment differences.