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Sculpture in downtown Tucson
Today, we spent the day in the Tucson area (See yesterday’s post here).
A few weeks ago I wrote an email to the folks at ASARCO’s Mineral Discovery Center (AMDC) southwest of Tucson. I told them we were coming for a visit and wanted to join one of their mine tours. Their tour involves taking a bus through the working open-pit Mission Mine, then a visit to one of their mills. As most of you know, my upcoming book SLAG includes my great great grandfather’s role in co-founding the American Smelting & Refining Company in 1899, now known as ASARCO. I asked if anyone at the Discovery Center would be curious to meet with us and learn about the book I was writing that included the early history of ASARCO.
Vice President of Environmental Affairs Thomas Aldrich, a forty year veteran of ASARCO, wrote back explaining that, yes, they would enjoy meeting us. Moreover, after the exchange of a few emails, he offered to take us on a personal tour of the mine facility. I thought that pretty generous, so I snapped up the offer before he could change his mind.
The AMDC is just off I-19, about twenty minutes south of Tucson.
On Tuesday morning we arrived at 9:00am for the 9:30am meeting (Sorry for rushing you out the door honey, but I got my times confused!). However, we put the early arrival to good use by watching the Discovery Center’s movie about ASARCO’s mining and smelting process. I found it particularly interesting, given my work on the book.
Beautiful grounds outside the Discovery Center.
After the movie, Sandra Elizondo, director of the AMDC introduced us to Tom Aldrich and Tom Klempel, Mission Environmental Manager. Together, Tom and Tom were in charge of wrangling us (basically keeping us out of trouble I think — apparently our reputation proceeds us). The four of us hopped into Tom K.’s truck and he drove us to the Mission MIne’s overlook. It takes some time to reach the top of the mine, so we had plenty of time to chat about ASARCO, the book, and each other.
At the mine overlook, the Toms explained the details of open pit mining, from the removal of the overburden, to the removal and tracking of the valuable deposits, to its processing in the mills. The copper at the Mission Mine is so low grade that only about 1% of the ore mined is copper. Put another way, the mine processes about three hundred truck loads of ore per day (see truck below), which results in three truckloads of copper. But, that’s been the story of most mines. It’s a volume business requiring transportation, industry, and science to profitably produce predictable amounts of valuable minerals.
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