Wednesday, February 7, 2018

Uranium was named for the planet Uranus

In my quest to more be skilled generally I’ve been working on mapping skills by downloading interesting-sounding data layers from the internet and trying to make something out of them.  Most recently I made this map of Utah mines [1]:

A few parts of the map struck me:
  • Fluorine-fluorite (coded ‘F’ in the data) and Uranium (coded ‘U’) are often mined in the same places, leading to the attribute table commodity code ‘FU.’  This is funny. 
  • The sand and gravel pits follow the base of the Rockies and length of I-15 quite nicely.
  • Look at all those uranium mines. I was in one of those once. 

I think the Cold War is interesting.  It’s amazing that during my lifetime but not in my memory Americans lived with the legitimate fear of nuclear war (it is not amazing that we are re-living this fear).  That between 1947 and 1991 we were engaged in an arms race that produced nuclear warheads small enough for three to fit on a single intercontinental ballistic missile and each capable of producing a 475 kiloton explosion (that’s equivalent to 475,000 tons of TNT)[2].  The first nuclear bomb, dropped in 1945, was almost 20 times heavier with a 15 kiloton yield[3].  The U.S has LOTS of nuclear weapons, which required lots of uranium.  While we’ve begun slimming down our stockpile of nuclear weapons, hundreds of abandoned uranium mines in Utah currently bear witness to that crazy period of time. 
Look at this stuff.  Isn't it neat?
Abandoned mines are an environmental hazard but abandoned places are also irresistible.  Brent, Karina, and I had planned for a day of mine exploration during our 2015 Spring Break trip.  I downloaded a list of uranium mines and we set off to look at the closest mines… which turned out to be active processing mills (read: do not trespass there).  This was disappointing, but Plan B was to drive the roads in the part of San Juan County with the highest density of active mines in hopes of finding something abandoned.  And it worked. 
Speak friend and enter  
Uranium is a heavy metal that is found in rocks, soil, and water.  It’s way more common than silver or gold.  Uranium can move through the earth with groundwater, driven by changes in oxygen availability that will keep the uranium bound to water or bound to rocks[4].  Sandstone can be lousy with uranium because it is porous (so uranium-laden water can move through it) and because most sandstone deposits were formed near or below ancient seas, where the oxygen availability fluctuated a lot.  It wasn’t a coincidence that the cliffs we were exploring had bands of red and green rock that showed when oxygen was (red) and wasn’t (green) available millennia ago.  
The grey rock coming out of the chute and below it is uranium ore
When mining, the key is to find uranium-bearing rocks that have enough concentrated uranium to make digging a tunnel, carrying the rocks out of the ground, and transporting them to a refinery worthwhile.  Then a refinery will need to see reason to crush, heat, and spin the ore until it is enriched enough that it can make atom-splitting chain reactions (the physics and chemistry, of course, are more complicated, but that’s the gist of it)[5].  Uranium by itself isn’t very radioactive at all and wasn’t the real threat while we were in the mines. 
Tunnels
Side note.  I’m also think water law is interesting and it follows a lot of the rules of mining. Did you know that the General Mining Act of 1872 still stands as the rules for how one claims and works a mine.  1. First to claim it owns it.  2. Mineral rights are separate from land rights (you don’t own the minerals below your home).  3. You have to put in $100 of labor per year to keep your claim valid. 

Only slightly less magnificent than the Door of Durin
The mines we explored were three separate claims with interconnected tunnels established in the 1950’s. The ores in the mines were a mix of uranium, vanadium, potassium, and sulphur; in practical terms, there were a lot of yellow rocks[1].  Prior to the Uranium Boom in Moab, mines extracted radium (for medicine) and vanadium (for making iron steel stronger), both of which are found in the same places as uranium[6].  We left the tunnels with mild headaches, which might have been due to vanadium gas. 
Note the white calcite and yellow salts
The Uranium Boom (approximately 1952-1961) was wild.  Staking lots of claims was profitable at that time because the U.S. government paid a guaranteed price for uranium and the Colorado Plateau had a lot to offer.  But as mentioned above, uranium isn’t uncommon and the market quickly became saturated and the government stopped buying uranium.  Most mines were abandoned by the 1970’s, leaving behind structures, mining refuse, and any equipment that wasn’t worth the cost of moving.  Miles of underground tunnels and heaps of uranium slag are just one facet of the unintended consequences that came to Utah with the Cold War arms race, along with stockpiles of neurotoxins in the West Desert and down-winder cancer deaths in southwestern Utah. 

We wandered around a couple miles of underground tunnels where we experienced true silence and darkness when we dared turn our headlamps off.  We found the remains of blasting caps and earthmoving machinery.  I discovered that I feel very uneasy underground while Brent is emboldened.  In the first tunnel he pushed ahead while I was farther back, taking very cautious steps.  Karina was caught in between us, but I found the bravery to lightly skip up to her, making sure not to take any heavy, earth-shaking steps.  Given how quiet the tunnel was, I thought I could use my inside voice to alert Brent to my fear and get him to come back.  I spent minutes saying, ‘Brent.  Can you come back here?” in a volume that doesn’t deserve an exclamation point and I got really frustrated that he never came back.  But I couldn’t yell for fear I would cave in the whole tunnel. 
My Fellowship of the Tunnels
The tunnels all went deeper into the sandstone, but we had to stop at the depth of the regional water table, below which the tunnels were flooded.  That is where we caught up to Brent, who promised he had not been ignoring my quiet pleas.  Some entrances required crawling into, which felt intrepid.  One entrance was quite large and grand, like the Mines of Moria.  It was exciting to get a glimpse into the semi-recent past and to have it all to ourselves.  The threat of trolls and Balrogs made it all the more interesting. 
Ever intrepid Karina
The uranium mines in the Four Corners Region still have tens of thousands of pounds of uranium ore left, but the cost of extraction is more than the price of the ore.  Like abandoned conventional weapon blast sites and missile launch pads (which I will detail later), they show what Utah was like during the Cold War. 

 Sources:
[1] Utah Automated Geographic Reference Center, “Minerals.” Geoscience, 2017,  https://gis.utah.gov/data/geoscience/
[2] “W87.” Wikipedia, Wikipedia, 5 Feb. 2018, https://en.wikipedia.org/wiki/W87.
 [3]  Wellerstein, Alex. “Kilotons per kilogram.” Nuclear Secrecy Blog, 23 Dec. 2013, http://blog.nuclearsecrecy.com/2013/12/23/kilotons-per-kilogram/.
 [4] “Uranium ore.” Wikipedia, Wikipeida, 5 Feb. 2018, https://en.wikipedia.org/wiki/Uranium_ore
[5]  Rhodes, Richard. Making of the Atomic Bomb.  Simon & Schuster, 2012. 
[6]”Utah’s Uranium Boom.” Utah History To Go, State of Utah, 2018,  http://historytogo.utah.gov/utah_chapters/utah_today/utahsuraniumboom.html