Question: Operation Roller Coaster was a series of nuclear tests conducted at a reservation located in what county?

full_context: Document 1: Desert National Wildlife Refuge: The Desert National Wildlife Refuge is a protected wildlife refuge, administered by the U.S. Fish and Wildlife Service, located north of Las Vegas, Nevada, in northwestern Clark and southwestern Lincoln counties, with much of its land area lying within the southeastern section of the Nevada Test and Training Range. The Desert NWR, created on May 20, 1936, is the largest wildlife refuge in the lower 48 states of the United States, encompassing 1.615 e6acre of the Mojave Desert in the southern part of Nevada. This Range is part of the larger Desert National Wildlife Refuge Complex, which includes the Ash Meadows National Wildlife Refuge, the Moapa Valley National Wildlife Refuge, and the Pahranagat National Wildlife Refuge.
Document 2: Project 56 (nuclear test): Operation Project 56 was a series of 4 nuclear tests conducted by the United States in 1955-1956 at the Nevada Test Site. These tests followed the "Operation Wigwam" series and preceded the "Operation Redwing" series.
Document 3: Lovelock Aerial Gunnery Range: Lovelock Aerial Gunnery Range was a World War II facility in two Nevada areas used for "aerial gunnery, strafing, dive bombing [and] rocket fire". By 21 November 1944, the Lovelock Range had been approved by the Secretary of the Navy to be developed for Naval Air Station Fallon, and on 13 January 1945, "Lovelock Air to Air" began when "leased under the Second War Powers Act". By February 1945, land was being acquired for the North Range in the Black Rock Desert which was 1122 that included 64.4 of "Patented" (leased private) land. The South Range in the Granite Springs Valley was 2436 , and in March 1945 "1920 Acres more" were added.
Document 4: Yucca Mountain: Yucca Mountain is a mountain in Nevada, near its border with California, approximately 100 mi northwest of Las Vegas. Located in the Great Basin, Yucca Mountain is east of the Amargosa Desert, south of the Nevada Test and Training Range and in the Nevada National Security Site. It is the site of the Yucca Mountain nuclear waste repository, which is currently identified by Congressional law as the nation's spent nuclear waste storage facility. However, while licensure of the site through the Nuclear Regulatory Commission is ongoing, political maneuvering led to the site being de-funded in 2010.
Document 5: Operation Teapot: Operation Teapot was a series of fourteen nuclear test explosions conducted at the Nevada Test Site in the first half of 1955. It was preceded by "Operation Castle", and followed by "Operation Wigwam". "Wigwam" was, administratively, a part of "Teapot", but it is usually treated as a class of its own. The aims of the operation were to establish military tactics for ground forces on a nuclear battlefield and to improve the nuclear weapons used for strategic delivery.
Document 6: Operation Storax: Operation Storax was a series of 47 nuclear tests conducted by the United States in 1962-1963 at the Nevada Test Site. These tests followed the "Operation Fishbowl" series and preceded the "Operation Roller Coaster" series.
Document 7: Operation Whetstone: The United States's Whetstone nuclear test series was a group of 46 nuclear tests conducted in 1964-1965. These tests followed the "Operation Niblick" series and preceded the "Operation Flintlock (nuclear test)" series.
Document 8: Pahute Mesa: Pahute Mesa is one of four major nuclear test regions within the Nevada National Security Site (NNSS). It occupies 243 sqmi in the northwest corner of the NNSS in Nevada. The eastern section is known as Area 19 and the western section as Area 20.
Document 9: Trinity (nuclear test): Trinity was the code name of the first detonation of a nuclear weapon. It was conducted by the United States Army at 5:29 a.m. on July 16, 1945, as part of the Manhattan Project. The test was conducted in the Jornada del Muerto desert about 35 miles (56 km) southeast of Socorro, New Mexico, on what was then the USAAF Alamogordo Bombing and Gunnery Range (now part of White Sands Missile Range). The only structures originally in the vicinity were the McDonald Ranch House and its ancillary buildings, which scientists used as a laboratory for testing bomb components. A base camp was constructed, and there were 425 people present on the weekend of the test.
Document 10: Operation Niblick: The United States's Niblick nuclear test series was a group of 41 nuclear tests conducted in 1963–1964. These tests followed the "Operation Roller Coaster" series and preceded the "Operation Whetstone" series.
Document 11: Operation Roller Coaster: Operation Roller Coaster was a series of 4 nuclear tests conducted by the United States in 1963 at the Nevada Test Site. These tests followed the "Operation Storax" series and preceded the "Operation Niblick" series.
Document 12: Santa Susana Field Laboratory: The Santa Susana Field Laboratory is a complex of industrial research and development facilities located on a 2,668 acre portion of the Southern California Simi Hills in Simi Valley, California. It was used mainly for the development and testing of liquid-propellant rocket engines for the United States space program from 1949 to 2006, nuclear reactors from 1953 to 1980 and the operation of a U.S. government-sponsored liquid metals research center from 1966 to 1998. The site is located approximately 7 mi northwest from the community of Canoga Park and approximately 30 mi northwest of Downtown Los Angeles. Sage Ranch Park is adjacent on part of the northern boundary and the community of Bell Canyon along the entire southern boundary.
Document 13: Yucca Mountain nuclear waste repository: The Yucca Mountain Nuclear Waste Repository, as designated by the Nuclear Waste Policy Act amendments of 1987, is to be a deep geological repository storage facility within Yucca Mountain for spent nuclear fuel and other high level radioactive waste in the United States. The site is located on federal land adjacent to the Nevada Test Site in Nye County, Nevada, about 80 mi northwest of the Las Vegas Valley.
Document 14: Nevada Test Site: The Nevada National Security Site (N2S2),(though the abbreviation NNSS is still used), previously the Nevada Test Site (NTS), is a United States Department of Energy reservation located in southeastern Nye County, Nevada, about 65 miles (105 km) northwest of the city of Las Vegas. Formerly known as the Nevada Proving Grounds, the site was established on 11 January 1951 for the testing of nuclear devices, covering approximately 1,360 square miles (3,500 km) of desert and mountainous terrain. Nuclear weapons testing at the Nevada Test Site began with a 1-kiloton-of-TNT (4.2 TJ) bomb dropped on Frenchman Flat on 27 January 1951. Many of the iconic images of the nuclear era come from the NTS. NNSS is operated by National Security Technologies, LLC, a joint venture of Northrop Grumman, AECOM, CH2M Hill, and Babcock & Wilcox.
Document 15: Operation Fulcrum: The United States's Fulcrum nuclear test series was a group of 21 nuclear tests conducted in 1976-1977. These tests followed the "Operation Anvil (Nuclear test)" series and preceded the "Operation Cresset" series.
ground_truth: Nye County