Operation Cornerstone

Cornerstone
Information
Country	United States
Test site	NTS Area 12, Rainier Mesa; NTS Area 19, 20, Pahute Mesa; NTS, Areas 1-4, 6-10, Yucca Flat
Period	1988-1989
Number of tests	11
Test type	underground shaft, underground tunnel
Max. yield	150 kilotonnes of TNT (630 TJ)
Navigation
Previous test series	Operation Touchstone
Next test series	Operation Aqueduct

The United States's Cornerstone nuclear test series^[1] was a group of 11 nuclear tests conducted in 1988-1989. These tests ^{[note 1]} followed the Operation Touchstone series and preceded the Operation Aqueduct series.

United States' Cornerstone series tests and detonations

Name [note 2]	Date time (UT)	Local time zone [note 3][2]	Location [note 4]	Elevation + height [note 5]	Delivery [note 6] Purpose [note 7]	Device [note 8]	Yield [note 9]	Fallout [note 10]	References	Notes
Dalhart	13 October 1988 14:00:00.08	PST (-8 hrs)	NTS Area U4u 37°05′20″N 116°03′00″W / 37.08895°N 116.05013°W	1,229 m (4,032 ft) - 639.78 m (2,099.0 ft)	underground shaft, weapons development		150 kt		[1][3][4][5][6]
Monahans - 1	9 November 1988 20:15:00.08	PST (-8 hrs)	NTS Area U3lk 36°59′28″N 116°01′19″W / 36.99116°N 116.02198°W	1,175 m (3,855 ft) - 289.86 m (951.0 ft)	underground shaft, weapons development		less than 20 kt		[1][5][6]	Simultaneous, separate holes.
Monahans - 2	9 November 1988 20:15:00.08	PST (-8 hrs)	NTS Area U6i 36°59′19″N 116°01′19″W / 36.98868°N 116.02197°W	1,174 m (3,852 ft) +	underground shaft, weapons development		less than 20 kt		[1][5][6]	Simultaneous, separate holes.
Kawich Blue - 4	9 December 1988 15:15:00.08	PST (-8 hrs)	NTS Area U8n 37°10′31″N 116°05′33″W / 37.17527°N 116.09261°W	1,357 m (4,452 ft) +	underground shaft, safety experiment		less than 20 kt		[1][5][6]	Simultaneous, same hole with white.
Kawich White - 3	9 December 1988 15:15:00.08	PST (-8 hrs)	NTS Area U8n 37°10′31″N 116°05′33″W / 37.17527°N 116.09261°W	1,357 m (4,452 ft) - 384 m (1,260 ft)	underground shaft, safety experiment		3 kt		[1][5][6]	Simultaneous, same hole with blue.
Misty Echo	10 December 1988 20:30:00.06	PST (-8 hrs)	NTS Area U12n.23 37°11′56″N 116°12′37″W / 37.19899°N 116.21032°W	2,232 m (7,323 ft) - 400 m (1,300 ft)	underground tunnel, weapon effect		25 kt	Venting detected, 7 Ci (260 GBq)	[1][5][6][7][8]
Texarkana	10 February 1989 20:06:00.055	PST (-8 hrs)	NTS Area U7ca 37°04′36″N 116°00′05″W / 37.07678°N 116.00137°W	1,267 m (4,157 ft) - 504.02 m (1,653.6 ft)	underground shaft, weapons development		67 kt		[1][3][4][5][6]
Kawich Black - 1	24 February 1989 16:15:00.08	PST (-8 hrs)	NTS Area U2cu 37°07′43″N 116°07′22″W / 37.1285°N 116.12267°W	1,352 m (4,436 ft) - 431 m (1,414 ft)	underground shaft, safety experiment		less than 20 kt	Venting detected	[1][5][6][7]	Simultaneous, same hole with red.
Kawich Red - 2	24 February 1989 16:15:00.081	PST (-8 hrs)	NTS Area U2cu 37°07′43″N 116°07′22″W / 37.1285°N 116.12267°W	1,352 m (4,436 ft) - 370 m (1,210 ft)	underground shaft, weapons development		5 kt	Venting detected, 10 Ci (370 GBq)	[1][5][6][7]	Simultaneous, same hole with black.
Ingot	9 March 1989 14:05:00.086	PST (-8 hrs)	NTS Area U2gg 37°08′34″N 116°04′04″W / 37.14279°N 116.06781°W	1,280 m (4,200 ft) - 500 m (1,600 ft)	underground shaft, weapons development		33 kt		[1][3][5][6]
Palisade - 1	15 May 1989 13:10:00.087	PST (-8 hrs)	NTS Area U4at 37°06′27″N 116°07′18″W / 37.10756°N 116.12176°W	1,338 m (4,390 ft) - 345.22 m (1,132.6 ft)	underground shaft, weapons development		5 kt	Venting detected, 2 Ci (74 GBq)	[1][5][6][7]	Simultaneous, same hole.
Palisade - 2	15 May 1989 13:10:00.09	PST (-8 hrs)	NTS Area U4at 37°06′27″N 116°07′18″W / 37.10756°N 116.12176°W	1,338 m (4,390 ft) - 392 m (1,286 ft)	underground shaft, safety experiment		less than 20 kt	Venting detected	[1][5][6][7]	Simultaneous, same hole.
Palisade - 3	15 May 1989 13:10:00.09	PST (-8 hrs)	NTS Area U4at 37°06′27″N 116°07′18″W / 37.10756°N 116.12176°W	1,338 m (4,390 ft) - 404 m (1,325 ft)	underground shaft, safety experiment		8 kt	Venting detected	[1][3][5][6][7]	Simultaneous, same hole.
Tulia	26 May 1989 18:07:00.021	PST (-8 hrs)	NTS Area U4s 37°05′09″N 116°03′24″W / 37.08587°N 116.05665°W	1,230 m (4,040 ft) - 397.8 m (1,305 ft)	underground shaft, weapons development		500 t		[1][3][5][6]
Contact	22 June 1989 21:15:00.83	PST (-8 hrs)	NTS Area U20aw 37°16′58″N 116°24′47″W / 37.28282°N 116.41319°W	1,980 m (6,500 ft) - 544.1 m (1,785 ft)	underground shaft, weapons development		60 kt		[1][5][6]
Amarillo	27 June 1989 15:30:00.02	PST (-8 hrs)	NTS Area U19ay 37°16′31″N 116°21′16″W / 37.27541°N 116.35444°W	2,019 m (6,624 ft) - 640.1 m (2,100 ft)	underground shaft, weapons development		20 kt		[1][5][6]
Disko Elm	14 September 1989 15:00:00.098	PST (-8 hrs)	NTS Area U12p.03 37°14′09″N 116°09′49″W / 37.23589°N 116.16374°W	1,917 m (6,289 ft) - 260 m (850 ft)	underground tunnel, weapon effect		10 kt	Venting detected, 0.5 Ci (19 GBq)	[1][5][6][7]

1. A bomb test may be a salvo test, defined as two or more explosions "where a period of time between successive individual explosions does not exceed 5 seconds and where the burial points of all explosive devices can be connected by segments of straight lines, each of them connecting two burial points and does not exceed 40 kilometers in length". Mikhailov, V. N., Editor in Chief. "Catalog of World Wide Nuclear Testing". Begell-Atom, LLC.
2. The US, France and Great Britain have code-named their test events, while the USSR and China did not, and therefore have only test numbers (with some exceptions – Soviet peaceful explosions were named). Word translations into English in parentheses unless the name is a proper noun. A dash followed by a number indicates a member of a salvo event. The US also sometimes named the individual explosions in such a salvo test, which results in "name1 – 1(with name2)". If test is canceled or aborted, then the row data like date and location discloses the intended plans, where known.
3. To convert the UT time into standard local, add the number of hours in parentheses to the UT time; for local daylight saving time, add one additional hour. If the result is earlier than 00:00, add 24 hours and subtract 1 from the day; if it is 24:00 or later, subtract 24 hours and add 1 to the day. All historical timezone data are derived from here:
4. Rough place name and a latitude/longitude reference; for rocket-carried tests, the launch location is specified before the detonation location, if known. Some locations are extremely accurate; others (like airdrops and space blasts) may be quite inaccurate. "~" indicates a likely pro-forma rough location, shared with other tests in that same area.
5. Elevation is the ground level at the point directly below the explosion relative to sea level; height is the additional distance added or subtracted by tower, balloon, shaft, tunnel, air drop or other contrivance. For rocket bursts the ground level is "N/A". In some cases it is not clear if the height is absolute or relative to ground, for example, Plumbbob/John. No number or units indicates the value is unknown, while "0" means zero. Sorting on this column is by elevation and height added together.
6. Atmospheric, airdrop, balloon, gun, cruise missile, rocket, surface, tower, and barge are all disallowed by the Partial Nuclear Test Ban Treaty. Sealed shaft and tunnel are underground, and remained useful under the PTBT. Intentional cratering tests are borderline; they occurred under the treaty, were sometimes protested, and generally overlooked if the test was declared to be a peaceful use.
7. Include weapons development, weapon effects, safety test, transport safety test, war, science, joint verification and industrial/peaceful, which may be further broken down.
8. Designations for test items where known, "?" indicates some uncertainty about the preceding value, nicknames for particular devices in quotes. This category of information is often not officially disclosed.
9. Estimated energy yield in tons, kilotons, and megatons. A ton of TNT equivalent is defined as 4.184 gigajoules (1 gigacalorie).
10. Radioactive emission to the atmosphere aside from prompt neutrons, where known. The measured species is only iodine-131 if mentioned, otherwise it is all species. No entry means unknown, probably none if underground and "all" if not; otherwise notation for whether measured on the site only or off the site, where known, and the measured amount of radioactivity released.

References

1. Yang, Xiaoping; North, Robert; Romney, Carl (August 2000), CMR Nuclear Explosion Database (Revision 3), SMDC Monitoring Research
2. "Timezone Historical Database". iana.com. Retrieved March 8, 2014.
3. Hechanova, Anthony E.; O'Donnell, James E. (1998-09-25), Estimates of yield for nuclear tests impacting the groundwater at the Nevada Test Site, Nuclear Science and Technology Division
4. Operation Argus, 1958 (DNA6039F), Washington, DC: Defense Nuclear Agency, Department of Defense, retrieved 26 November 2013
5. Official list of underground nuclear explosions, Sandia National Laboratories, 1994-07-01, retrieved 2013-12-18
6. United States Nuclear Tests: July 1945 through September 1992 (PDF) (DOE/NV-209 REV15), Las Vegas, NV: Department of Energy, Nevada Operations Office, 2000-12-01, retrieved 2013-12-18
7. Radiological Effluents Released from U.S. Continental Tests 1961 Through 1992 (DOE/NV-317 Rev. 1) (PDF), DOE Nevada Operations Office, August 1996, retrieved 2013-10-31
8. Norris, Robert Standish; Cochran, Thomas B. (1 February 1994), "United States nuclear tests, July 1945 to 31 December 1992 (NWD 94-1)" (PDF), Nuclear Weapons Databook Working Paper (Washington, DC: Natural Resources Defense Council), retrieved 2013-10-26