The Gay Mine

The Gay Mine is located on the Fort Hall Reservation. It is one of 31 phosphate ore mines in the Southeast Idaho Phosphate Resource Area. Originally named after Gay Simplot, the daughter of J.R. Simplot, the Gay Mine came into existence in 1946 to supply phosphate ore to the J.R. Simplot Company (Simplot) fertilizer plant in Pocatello. FMC Corporation (FMC) received ore under an ore supply agreement from 1948 to 1993.

The Gay Mine consists of a series of phosphate ore deposits mined by the J.R. Simplot Company from 1946 to 1993, when the Gay Mine ceased operations. The Gay Mine was operated under mineral and business leases between the Shoshone-Bannock Tribes (Tribes) and individual Tribal members (allottees) as lessors, and the J.R. Simplot and FMC as lessees. Simplot held the majority of the Gay Mine leases, and FMC entered into leases beginning in 1956. In 2003, the Bureau of Indian Affairs (BIA) issued a determination that the Gay Mine mineral leases had expired of their own terms. Over the life of the mine, FMC and Simplot paid approximately $60 million in royalties and rent to the Tribes and Tribal landowners for the extraction of ore from the Gay Mine. The Gay Mine was a source of employment for many Tribal members.

During its operation, all mining leases and mining plans at the Gay Mine were subject to the approval of the Shoshone-Bannock Tribes and the BIA. The BIA acted as the agent for the Shoshone-Bannock Tribes and individual Tribal landowners and collected rent and royalties for properties that were leased for phosphate mining at Gay Mine. Mining activity at the Gay Mine was continuously regulated by the Department of Interior.

The Fort Hall Business Council of the Shoshone-Bannock Tribes agreed by resolution, or the individual allottee(s) agreed by signature, to all mining and reclamation work conducted at the Gay Mine. The Tribes and the allottees agreed to the mine work with BIA approval and technical input and support from BLM. As the lessor of the Gay Mine, the Tribes had an active role in reviewing and approving environmental aspects of the Companies’ mining operations, including the mining waste disposal activities. Federal regulations required concurring approval by BIA, which received technical support from BLM. Only after the Companies had obtained Tribal approval would BIA review and approve mining and reclamation plans.

Downsizing the operations at the Gay Mine began in 1988 when Simplot switched from hauling dry ore via railcar to transporting phosphate ore slurry from the Smoky Canyon Mine to its fertilizer plant via pipeline. After this change occurred, Simplot no longer used ore from the Gay Mine because its fertilizer production process could only use the phosphate ore slurry. A further factor was that by that time the mine had very little remaining process grade ore. FMC began earnestly looking for a new source of ore and concluded that the best source of ore was at the Dry Valley Mine in Caribou County, Idaho.

The Gay Mine closed in 1993. In an effort to continue mining operations, the Tribes commissioned and funded an analysis to assess whether other areas at the site could be economically mined. In the end, the Tribes’ consultant agreed with FMC’s analysis that it was not economically feasible to relocate all of the facilities, such as buildings, loading areas, rail, utilities and water, and other necessary infrastructure to a new location.

Upon the closure of the Gay Mine, the Companies removed most of the operational facility, referred to as the campsite, including fuel storage tanks and other structures. A contractor dug up all of the soil around the campsite that was found to have been contaminated by vehicle maintenance activities. The excavated soil was laid out and land-farmed to let soil bacteria destroy the fuel contaminants, which consisted of traces of oil, diesel and gasoline.

Soil samples from the land-farm showed that risk-based cleanup levels were achieved by the end of the 1999 season. A final report and revegetation plan for the land-farm were submitted to the Agencies and the Tribes in June 2000. FMC and Simplot proposed to conduct the land-farm revegetation as part of the mine site reclamation once the Agencies and the Tribes approved the revegetation plan. But the Agencies and the Tribes did not approve or disapprove that plan and therefore it was never implemented.

Over the years, the Tribes considered several initiatives to independently develop the Gay Mine as a source of Tribal revenue. Among the initiatives considered were options to: process the mill shale piles for fertilizer manufacture; convert the Gay Mine to a municipal landfill and/or hazardous waste incinerator site; and convert the Gay Mine to a historical tourist attraction. None of these initiatives has progressed past the idea phase.