Locatable minerals (metallic and nonmetallic) are those open to mining claim location under the General Mining Law of 1872, as amended (30 U.S. Code [U.S.C.] 22‐54 and 611‐615). The primary locatable minerals mined commercially in the Planning Area are bentonite (Map 4) and gypsum (Map 5). Other locatable minerals known to occur in the Planning Area include titaniferous sandstone, placer gold, uranium, and sulfur; however, these minerals are not known to occur in commercially viable quantities in the Planning Area. Silica sand is present in the Bighorn Basin in the John Blue Canyon deposit, and is of sufficient quality for glass, fused silica, metallurgical flux, abrasives, fillers in ceramics, and as an ore for making silicon metal (BLM 2009c). However, the prohibitive quantity of overburden overlying known silica sand resources would make any attempt at commercial production very difficult. Base and precious lode metals such as gold, silver, platinum, and copper are not known to occur in commercial quantities in the Bighorn Basin. Precious and semiprecious stones are not known to occur in the Planning Area. For more information on locatable minerals in the Planning Area, refer to the Solid Mineral Occurrence and Development Potential Report (BLM 2009c).

A mining claim is an ownership interest in a particular parcel of federal land that is valued for a specific mineral deposit. Mineral prospecting and claim location can take place only on lands open to mineral entry. Claims may not be staked in areas withdrawn from mineral entry by a special Act of Congress, regulation, or public land order. These areas are withdrawn from the operation of the mining laws.

The right of possession provided by a mining claim is restricted to the extraction and development of a mineral deposit as regulated by the BLM or the USFS. The rights granted by a mining claim are valid against a challenge by the United States and other claimants only after the discovery of a valuable mineral deposit. A mining claim is generally referred to as a “lode claim” if mineralization occurs as a vein of ore in place, or as a “placer claim” if minerals are dispersed among particles of sand or gravel. A millsite claim is one used to process locatable minerals.

The BLM locatable mineral program addresses authorization and permitting of locatable mineral exploration, mining, and reclamation activities on BLM-administered land, and is mandated by section 302(b) of the Federal Land Policy and Management Act of 1976 (FLPMA) (43 U.S.C. 1732[b] and 603[c]; 43 CFR 3802 and 43 CFR 3809). All locatable mineral exploration and development activities that disturb the surface of the mining claim (site) require prior BLM acceptance (for a notice) or authorization (for a plan of operations). Operations obtain necessary authorizations and permits through the BLM field office responsible for administering the land in which the minerals are located.

Operators must obtain all necessary permits before they begin mining, even if they already filed a mining claim. Surface management regulations apply to activities on unpatented mining claims. These regulations are designed to prevent unnecessary or undue degradation of public lands from operations authorized by the mining laws. They require the filing of a notice or a plan of operations for all activity exceeding casual use. Regulations that went into effect on January 20, 2001 (revised 3809 regulations), require that notices include a bond, and will only apply to exploration activities, not to any production operations. Disturbed areas must be reclaimed after exploration and mining activities are completed. The state of Wyoming also has statutes and rules regarding mining and reclamation requirements. To avoid duplication, the BLM and the Wyoming DEQ have entered into a cooperative agreement via a Memorandum of Understanding (MOU). Operators are advised to check with the BLM and the Wyoming DEQ to determine the proper lead agency before submitting a notice or plan of operations.

Bentonite and gypsum are the only locatable minerals currently extracted in commercial quantities in the Planning Area. Bentonite consists of hydrous silicate of alumina, more commonly known as montmorillinite or beidelite. It can swell up to 16 times its original size, and absorb up to 10 times its own weight in water. It is used for absorbents, animal feed, drilling fluids, foundry, iron-ore pelletizing, and sealants. It is increasingly being used for cat litter, and this could become the largest single market for Wyoming bentonite early in the 21st Century. It is used in drilling mud to lubricate oilfield drilling equipment, hold back formation pressure, and to help prevent caving of the drill hole. Used in the foundry industry, it acts as a molding sand binder when added to taconite and for binding iron pellets, which are later fed into a blast furnace for processing. Bentonite is also used to seal reservoirs and landfills. Other uses include crayons, medicines, food thickeners, and cosmetics.

Bentonite deposits in Wyoming make up approximately 70 percent of the world’s known supply. In 2007, Wyoming’s bentonite industry mined approximately 5.9 million tons of bentonite, of which approximately 2.8 million tons were mined at six operations in the Bighorn Basin. The six mines in the Bighorn Basin employ 132 persons, and another 360 persons are employed at the milling‐processing facilities at six different mills (one in the Worland area, two near Greybull, and three near Lovell, Wyoming). The Wyoming DEQ Land Quality Division permits these broad mining areas; the BLM has surface management plan of operation files covering portions of bentonite mine operations on public lands.

Wyoming bentonite production has increased from 1,141 tons in 1927, to more than 500,000 tons in 1950, more than 2 million tons in 1970, almost 3 million tons in 1990, and more than 4.5 million tons in 2005. Production of Wyoming and Bighorn Basin bentonite has been relatively steady since 2005.

Gypsum (hydrated calcium sulfate) is used primarily in the manufacture of plaster. The development of prefabricated wallboard revolutionized the industry again in the 1960s. Approximately two-thirds of the gypsum currently marketed is in the form of prefabricated products. Gypsum is precipitated primarily from seawater, but can be deposited in saline lakes or hot springs. It often occurs as a product of volcanic activity and can occur in metallic mineral veins.

Commercially important gypsum deposits in the Bighorn Basin are found only in the Jurassic Gypsum Spring Formation. Two mines actively mine gypsum in the Planning Area (CYFO) and employ up to 200 persons in their mines and mills. The CertainTeed gypsum mine is south of Cody, Wyoming, and produces from three thick gypsum beds totaling approximately 35 feet. The Georgia Pacific Gypsum, LLC, mine southeast of Lovell, Wyoming, mines nine seams of gypsum, each separated by thin red shale, for a total of approximately 30 to 40 feet of gypsum.

Most of the gypsum from the Bighorn Basin is used to make wallboard, although other related products are also being made. A total of about 1.5 million tons of gypsum have been mined in the Planning Area since commercial mining began.

Table 3-10 lists active mining notices, the number of plans of operation, and production quantities for bentonite and gypsum in the Planning Area.

Management Challenges

Management challenges for locatable minerals in the Planning Area include surface disturbance and impacts to other resources due to mining activities. Approximately 30,000 acres of land has been disturbed in the Bighorn Basin due to bentonite mining, along with approximately 4,000 acres of road and haul-road disturbance (BLM 2008c). Between the CYFO and the WFO, another 20,000 acres of bentonite mining is a RFD scenario over the next 20 to 30 years (BLM 2008c).

As surface disturbance due to increased amounts of locatable mineral mining continues to grow in the Planning Area, loss of native habitats and resources increases. Sagebrush is very difficult to reestablish once removed, and can take 30 to 50 years to become reestablished in a mined area. Critical thresholds relevant to continued development of locatable minerals in the Planning Area have not been specifically determined under the existing management scenario. However, using the Geographic Information System (GIS), the BLM might be better able to determine threshold levels of disturbance in relation to locatable mineral (primarily bentonite) mining, and be better able to make future decisions because of these capabilities. A major challenge the BLM faces relates to improvement of sagebrush reclamation in mine areas and determination of direct and cumulative effects of locatable minerals mining on sage-grouse and their habitat, and how to mitigate these effects. In particular, the cumulative, ongoing effect of bentonite mining related to loss of sagebrush habitat and reclamation issues, coupled with the increase in focus on protection of the greater sage-grouse, will become a much more important issue for the BLM.