Geology
Potash-bearing brines may be alkaline or enriched in chloride, sulfate, or calcium, depending on the geology within the drainage basin and the resultant chemistry of the inflows to the basin. Potashbearing brines form in salt lakes and salars or playas in closed basins in arid environments, where high rates of near-surface evaporation concentrated the brine. The duration of this process can extend from hundreds of years to tens of thousands of years, and in some cases, over a million years. The potash-bearing brines of the Great Salt Lake and at Wendover, Utah, in the Great Salt Lake Desert are remnants of this lake. These brine-bearing basins are commonly structural basins that formed in volcaniclastic terranes.

The chemical constituents of the water flowing into a potash-bearing basin from precipitation runoff, groundwater, and hydrothermal springs have commonly been scavenged from the local country rocks. Source rocks of the constituents are most commonly acidic to intermediate volcanic rocks, but also include older saline rocks and continental sedimentary rocks (Alonso and Risacher, 1996; Risacher and Fritz, 2009). Sources of potassium in these rocks are weathered minerals, such as orthoclase, microcline, biotite, leucite, and nepheline. Studies have found a positive correlation between potassium, lithium, and boron in brines (Zheng, 1984; Orris, 1997; Carmona and others, 2000), which is probably indicative of their common origin in volcaniclastic terranes that typically are associated with convergent plate boundaries (Orris, 1997). Elevated levels of magnesium are also typical of many of the closedbasin brines.

Closed-basin potash-bearing brine deposits are one of the sources of potash occurring within the United States. Potash production from the Great Salt Lake and at Wendover, Utah is from this deposit type. On a global basis, these deposits are of highly variable size in terms of the amount of contained potash.

Potash at Wendover is produced primarily from brine containing salt, potash and magnesium chloride that is collected in ditches from the shallow aquifers of the West Desert. These materials are also collected from a deeper aquifer by means of deep brine wells.

Brine from a shallow potash containing aquifer is collected in over 100 lineal miles of open ditches throughout the 88,000 acres of land controlled by Intrepid. In addition to the brine that is collected in the shallow aquifer, there is a deep potash containing aquifer 1,000 feet below ground.

The Wendover facility has a current estimated productive capacity of approximately 100,000 tons of potash annually; evaporation rates have historically resulted in actual production between approximately 65,000 and 100,000 tons of potash.

Pump the brine collected in the ditch system into an 8,000 acre solar evaporation pond to evaporate water and precipitate salts. Over five billion gallons of brine are pumped into the solar pond system each year. As the brine becomes saturated with potash, it is transferred through a series of smaller evaporation ponds into harvest ponds. When the ripened brine finally reaches the harvest ponds, the ore (a combination of salt and potash) precipitates onto the pond floor. The remaining brine in the harvest ponds is removed and the ore is harvested and transported by elevating scrapers to the mill for processing. In the mill, the potash is separated from the salt by flotation. The material is then dried, compacted, and screened into standard ........