Owens Lake operations

Site history 

Located about 120 miles north of our Boron operations, mineral extraction has occurred in and around Owens Lake since the late 1870s. When the Los Angeles Aqueduct was completed in 1913, water was diverted away from Owens Lake. This diversion caused the lake to dry in the late 1920s.  

In 1962, Morrison and Weatherly Chemical Corporation (M&W) began mining trona from the dry lake bed—supplying our Boron Operations among others. U.S. Borax, part of Rio Tinto, purchased the mine in May 1999.

Early days at Owens Lake trona mine
Train moving from Owen's Lake to Boron operations

Today’s operations 

The State of California owns all of Owens Lake up to the high water mark determined in a 1913 survey. We own more than 300 acres of land in several parcels along the west side of Owens Lake and hold leases and Right of Way from the state. 

Our trona operations are centered mostly in the brine pool area where we isolate blocks of ore from the main ore body. We dewater and air dry these isolated blocks. The dried trona is then shipped from the site. 

The operations also includes a small office and laboratory for on-site testing. 

What is trona? 

Owens Lake is the third largest trona deposit in the Americas. But what is it exactly? Trona is a naturally occurring double salt of sodium carbonate and sodium bicarbonate with two waters of hydration. We use trona from Owens Lake to process borate ores at our Boron Operations.

Owen's Lake with mountains


Owens Lake Map

U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 650 customers with more than 1,800 delivery locations globally. We supply around 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles.  Learn more about Rio Tinto.

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