Mountains of Salt Beneath Us

I'm in the middle of reading Gandhi's autobiography "The Story Of My Experiments With Truth", and how significant of a role salt used to play in British colonial ruled India.  I've worked with industrial customers who make salt, and on the West side of Phoenix, not far from the Glendale stadium where the Arizona Cardinals play, there's a LARGE Morton salt facility.  And while you might think "it's Arizona, there's not much water, so where are they getting the salt?"  You can think a few hundred miles north, to Utah, where all around the Great Salt lake, there's massive salt reserves, left over, from the evaporation of the inland sea that used to exist millions of years ago between the Sierra Nevada mountains and the Rockies.  That inland sea stretched all the way to where Mexico is today. In fact, Dr Desert Flower and I learned at the Desert Botanical Garden geology class we took 3 years ago, that the ocean has covered Arizona 4 or 5 times, since North America was first formed.

So while images of elaborate salt carvings and deep mine shafts are what most people think of when they picture a salt mine, that's only one of many methods to extract salt from the earth (rock salt, or halite) and doesn't account for Solar salt (sea salt) or Evaporated salt (refined salt).  The evaporated salt, can be just about anywhere, and if you don't see large piles of white salt, you'd never know it. 

Take for instance, the Morton salt facility in Glendale. 

Those white pipes that are going into the ground, are not part of some natural gas pipe line.  No, they're pumping fresh water (yeah, in the Arizona Desert) down into the ground, and pulling brine laden solution back up to the surface.  Then they do some conditioning (might be membrane separation or something, I don't know) and pump the remaining briny solution into LARGE open pits where the unrelenting Sonoran sun quickly evaporates the water away, leaving salt behind, that they scoop up.

I first noticed this technique when I was driving through the Western Dutch countryside, near Hengelo Netherlands.  I saw these extensive networks of pipes, where the pipes were not irrigating the farm fields, but instead, were pumping water into the ground and returning brine solution back to a large industrial salt plant, where the water is evaporated away and the salt turned into products that European salt lovers desire. 

Most of Phoenix, and all of Glendale, and Luke Air Force Base to the West of Glendale, sit on about 1500 feet of silt, deposited there with each of the 4 or 5 historic ocean floodings the valley has been through.  And down inside that silt, is alot of salt.  Some of it, concentrated, as you can see from the Salt Institute's handy map above.  

Turns out that such large salt concentrations are all over the place.  Nearly the entire lower peninsula of Michigan is sitting on a massive concentration of salt.  Pakistan, Poland, The Netherlands, Pennsylvania, parts of China, also have massive salt concentrations.  So while you thought that your city, town, or your own personal property is not being disturbed or drilled under, you're probably wrong.  Between evaporated salt extraction, and natural gas fracking, it's increasingly likely that there's some industrial fluids being circulated beneath you, right now.  And to make it more interesting, often times with salt domes, they're found adjacent to oil & gas deposits!   Hooray for more fossil fuel production!! And...  if your salt tastes a little oily or pungent, don't worry.  It's probably just residual fracking fluid.

Yummy!   From now on, I'll be using only sea salt in my food, and avoiding large scale industrial salt production who may, or may not, have their customers' health held in a higher priority than profits. The Salt of the Month Club my friend Zim mentions, is an awesome idea indeed.