[10] During the late 20th century, military activities, including the destruction of a mill and the restriction of access to the mine, continued to affect work there.

[13] According to Nevada Bureau of Mines and Geology in 1998, the property claim, which is commonly referred to as Groom, is officially named "Conception".

[13] Based on panning samples near Groom Mine, the area may also contain deposits of antimony, barium, lead, mercury, and zinc.

[28] A 1990 Bureau of Land Management report stated that due to restricted access to the mine, it would lead to "potential loss of income through inability to expand or further develop the claims".

[10] The outhouse and bunkhouse at the mine were accidentally strafed during the war by aircraft using the Las Vegas Bombing and Gunnery Range.

[31] In 1951, the Atomic Energy Commission informed the Sheahan family of the planned detonations and set up instrumentation at the mine.

[24][32] The instrumentation was monitored by an employee of the United States Public Health Service, who lived at the mine along with the Sheahan family.

[37] It was, however, the view of the Atomic Energy Commission that the nuclear detonations "had not subjected Groom Mine personnel to any real danger from fallout".

[39] Following the adverse environmental impact observed by the two remaining family members at the mine caused by Upshot-Knothole Harry, the Atomic Energy Commission said the blasts were designed to produce winds from the testing area towards Groom rather than towards Las Vegas.

[24] During 1953, the property was strafed and during the summer a bomb destroyed the mine's mill;[40] no specific claim was made by the Sheahan family against the United States Air Force (USAF) for the event.

[47] Beginning in late 2014, the United States Department of Defense attempted to purchase the property from the Sheahan family, originally offering $1.5 million.

[10][48] In August 2015, a government press release described the mine as a "safety and security risk", even though the Sheahan family had not disclosed any activities of the Groom Lake facility.

On 16 September 2015, the property was condemned under eminent domain and given to the United States Government by a court order signed by federal Judge Miranda Du.

[8] It was not determined at the time of transfer of ownership how much the Sheahan family would receive in just compensation for the government acquisition of Groom Mine; the USAF in 2015 estimated the land to be worth $1.2 million.

[57] The landowner's experts valued those rights at $50 million based on the property being developed into a commercial tourism enterprise offering views of Area 51.

[58] On May 29, 2020 the Land Commission ruled that just compensation for the taking of the surface rights is $1,100,000 based on the property's continued use for rural recreation, with a premium over the Government's valuation to account for its view of Area 51 and its historic use as a family owned mining operation.