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FMC Green River is a multi-faceted mining and production facility supplying some of the most well-known products used around the globe. We are proud to employ several generations of families and harness the latest technological innovations in Wyoming.

At FMC Corporation, safety is job #1. Our working philosophy at FMC Green River is: “We believe nothing is more important than the safety of our employees, contractors and suppliers who support our operations. And first and foremost, we are a company of people.”

We operate the world’s largest underground trona mine for the production of soda ash and other sodium-based chemicals.

Trona is a mineral that is an essential component in making glass, fiberglass, tableware, lighting and screens for consumer electronics. Used both domestically and internationally, it is also a key ingredient in detergents and a building block for many other chemicals. Other diverse uses include animal feed, food grade products and pharmaceuticals.

For more than 60 years, FMC has been mining trona, now producing more than 4 million tons annually. FMC Green River ships more than 40,000 rail cars annually; if connected end to end, the rail cars would span nearly 500 miles. In addition, Green River ships over 5,000 truck orders per year.

FMC is the largest employer in Southwest Wyoming with approximately 900 employees, representing 20 percent of FMC’s global workforce. Green River is FMC’s largest manufacturing facility worldwide with eight processing plants and an underground mine approximately 1,600 feet below the surface -- the equivalent of 170 stories down. The mine measures 38 square miles and has 2,500 miles of tunnels, more than the city of San Francisco’s 1,500 miles of roadways.

Our History

It all started with a rock called “Trona.”

The story of FMC Green River actually began some 50 million years ago when the area FMC now occupies was at the bottom of a 1,000 square-mile land locked body of water geologists refer to as Lake Gosiute. Over millions of years, runoff from the surrounding mountains carried sodium rich compounds into the lake. The sodium reacted with carbon dioxide to form the mineral called trona. Over millions of years, this reaction created the largest trona deposit in the world and, as Lake Gosiute dried up, an estimated 130 billion tons of trona were deposited across the Green River Basin.

Trona is the mineral name for a chemical called sodium sesquicarbonate, sometimes called “sesqui.” The trona beds were discovered in 1938 while exploring for oil and gas. Since then, trona from the Green River Basin has become the source for production of high quality soda ash and other sodium products that ship throughout the world.