US Borax Trona Mine
Owens Lake, California

  Trona is excavated by digging a trench with the tracked excavator (below). The wet ore is then dumped to the side of the trench, where it is moved by dozers to form thin layers and left to dry in the sun. 
  The tracked excavator, parked above the trona trench. 
  The dozer used to move the excavated trona into l layers and again into piles for loading into haul trucks. 
  The tracked excavator, above the trona trench. Note the dark material in the trench bottom, this is lake sediments, silt and other similar material from a brackish water structure, that once was Owens Lake. 
  The mine geologist, explaining the nature of the deposit, and the mine operations. 
Once the trona is dried, it is placed into piles, approximately equal to the haul truck capacity, and loaded into the trucks for transport to the Borax Mine, where it is used in processing the borax ores. Some trona is also used as a feed additive for cattle and chicken feed. If local markets develop for higher quality trona, plans for a processing plant are on "the drawing board".
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