Plant Operations

World-Class Plant Operations

Our Trona Mine: An Underground City

Our primary trona bed is located 1,600 feet underground and averages about 10 feet thick. Virtually every day of the year, Green River’s mine workers ride elevators down 170 stories to the mine’s subsurface, which spans about nine miles from north to south, and six miles from east to west. Over the decades of mining trona here, some 2,500 miles of tunnel systems have been created. By contrast, the city of San Francisco has about 1,500 miles of roadway.

Mining Methods

The two methods used to extract trona are called “room and pillar” mining and longwall mining. Room and pillar mining means that some trona is removed, creating a “room”, and some trona is left behind to form the “pillar” that supports the mine’s tunnels. Longwall mining is done with a 750-foot long machine that removes 100 percent of the ore in its path, making it more efficient than room and pillar mining.

Genesis Alkali operates two manufacturing sites. The Westvaco facility was established in 1948. It is one of the lowest-cost, natural soda ash operations in the world. The second site, the Granger facility, was acquired from Texas Gulf Soda Ash in 1999. Within Westvaco and Granger, Genesis Alkali operates eight processing facilities, comprising the world’s largest natural soda ash mine and production site in the world:

Sesqui Plant

Constructed in 1953, the sesqui plant was the first soda ash plant at the Green River site. It produces multiple grades of soda ash, sodium sesquicarbonate (S-carb) crystals, and sodium sesquicarbonate slurry as feedstock for the production of sodium bicarbonate.

Mono Plants 1 & 2

The mono process, which Green River helped to pioneer, converts sodium feedstocks, primarily trona, into refined soda ash. The mono plants also supply the caustic plant with centrifuge cake for the production of caustic soda.

Caustic Plant

Chemical grade caustic soda is the primary product of the caustic process (also known as sodium hydroxide, caustic, and lye). Caustic soda is a versatile chemical used in manufacturing processes as well as in cleaners, pulp and paper products, oil production and refining, aluminum, food processing, bleach, water treatment, and mining.

ELDM Plant

ELDM is an acronym for the major steps used in a process to produce a dense soda ash: evaporation, lime neutralization, decahydrate crystallization, and monohydrate crystallization. Green River pioneered solution feed processing in the Wyoming trona basin when it began underground tailings injection, and then built the patented ELDM process to refine the recycled trona recovered during tailings injection. The ELDM process is the lowest cost in the world.

Bicarb Plant

The sodium bicarbonate (baking soda) plant produces products used in the industrial food, pharmaceutical, and animal feed industries. Genesis’s optimized production facilities allow it to make a wide grade of products, with special focus on specialty offerings, such as hemodialysis-grade bicarb for the healthcare industry.

Dredge Reclamation Operation

Genesis Alkali’s Green River dredge operations reclaim production-grade alkali for use in the company’s mono or ELDM plants. The process begins at an evaporation lake where decahydrate (deca) crystals are formed. The dredge cuts the deca crystals from the lake bottom and adds water to form a heavy slurry. This slurry is separated to remove the lake water, then heated and dissolved. In the end an alkali solution is left, which aids in the production of soda ash.

Manufacturing Excellence

At Green River, we constantly work to maintain world-class operations. As industry leaders, we are heavily invested in technology development and enhancement throughout our eight facilities. Through the collaboration of our operators, maintenance personnel, and all functional areas of the site, we are implementing and refining systems to ensure production reliably, efficiency and consistency. We have also improved safety performance year after year, maintained or improved our environmental compliance, and made major strides in capacity utilization at each of our facilities.


Our site has long been on the leading edge of advances in trona harvesting methods to maximize recovery, as well as refining initiatives. Green River has led the way in developing the present day bore miner, which replaced the former “drill and blast” mining method. We operate the first successful long wall miner, which boosts trona recovery and improves safety. And we improve recovery further by using solution mining and dredging our evaporation lake.

As the leader in trona mining and processing, we continue to develop innovative mining techniques and proprietary process strategies to ensure a reliable and economical alkali supply to our global customers.