Operation Bedrock Explained

Operation Bedrock
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:	1974–1975
Number Of Tests:	27
Test Type:	underground shaft, tunnel
Max Yield:	750ktTNT
Next Series:	Operation Anvil (nuclear test)

The United States's Bedrock nuclear test series was a group of 27 nuclear tests conducted in 1974–1975. These tests ^[1] followed the Operation Arbor series and preceded the Operation Anvil series.

United States' Bedrock series tests and detonations
- !style="background:#ffdead;"	Name ^[2] !style="background:#efefef;"	Date time (UT) !style="background:#ffdead;"	Local time zone^[3] ^[4] !style="background:#efefef;"	Location^[5] !style="background:#ffdead;"	Elevation + height ^[6] !style="background:#efefef;"	Delivery ^[7] Purpose ^[8] !style="background:#efefef;"	Device^[9] !style="background:#ffdead;"	Yield^[10] !style="background:#efefef;" class="unsortable"	Fallout^[11] !style="background:#ffdead;" class="unsortable"	References !style="background:#efefef;" class="unsortable"	Notes	- ! Escabosa	16:00:00.092	PST (–8 hrs)	NTS Area U7ac 37.075°N -116.0327°W	1223m (4,012feet) – 638.52m (2,094.88feet)	underground shaft, weapons development			I-131 venting detected, 0			- ! Crestlake-Briar - 1	14:00:01.2	PST (–8 hrs)	NTS Area U2dw 37.1193°N -116.086°W	1274m (4,180feet) – 373.68m (1,225.98feet)	underground shaft, weapons development			Venting detected		Simultaneous, same hole.	- ! Crestlake-Tansan - 2	14:00:01.2	PST (–8 hrs)	NTS Area U2dw 37.1193°N -116.086°W	1274m (4,180feet) – 272m (892feet)	underground shaft, weapons development			Venting detected, 19Ci		Simultaneous, same hole.	- ! Puye	14:00:00.11	PST (–8 hrs)	NTS Area U3jl 37.0234°N -116.0371°W	1188m (3,898feet) – 430.08m (1,411.02feet)	underground shaft, weapons development			I-131 venting detected, 2E-06Ci			- ! Portmanteau	15:00:00.163	PST (–8 hrs)	NTS Area U2ax 37.1524°N -116.0846°W	1313m (4,308feet) – 655.32m (2,150feet)	underground shaft, weapons development						- ! Pratt	14:00:00.08	PST (–8 hrs)	NTS Area U3hq 37.0121°N -116.031°W	1183m (3,881feet) – 313.96m (1,030.05feet)	underground shaft, weapons development						- ! Trumbull	14:30:00.164	PST (–8 hrs)	NTS Area U4aa 37.0932°N -116.0956°W	1269m (4,163feet) – 262.74m (862.01feet)	underground shaft, weapons development						- ! Stanyan	15:05:00.17	PST (–8 hrs)	NTS Area U2aw 37.1326°N -116.0693°W	1275m (4,183feet) – 573.02m (1,879.99feet)	underground shaft, weapons development						- ! Estaca	17:13:00.118	PST (–8 hrs)	NTS Area U3ja 37.0064°N -116.0156°W	1180m (3,870feet) – 321.05m (1,053.31feet)	underground shaft, weapons development						- ! Hybla Fair	15:00:00.168	PST (–8 hrs)	NTS Area U12n.09 37.2011°N -116.2048°W	2227m (7,306feet) – 404.47m (1,327feet)	tunnel, weapon effect			Venting detected, 500Ci		Test of a new line-of-sight pipe configuration for tunnel testing, basic measurements of blast parameters. The configuration proved to be inadequate for effects testing of warheads.	- ! Temescal	15:30:00.164	PST (–8 hrs)	NTS Area U4ab 37.0931°N -116.0925°W	1263m (4,144feet) – 262.74m (862.01feet)	underground shaft, weapons development			Venting detected, 2Ci			- ! Puddle	15:00:00.9	PST (–8 hrs)	NTS Area U3kg 37.001°N -116.0121°W	1169m (3,835feet) – 183.97m (603.58feet)	underground shaft, safety experiment						- ! Keel	17:30:00.088	PST (–8 hrs)	NTS Area U3hu 37.0114°N -116.0183°W	1182m (3,878feet) – 304.72m (999.74feet)	underground shaft, weapons development						- ! Portola - 1	15:30:00.165	PST (–8 hrs)	NTS Area U10bb 37.1784°N -116.0524°W	1285m (4,216feet) – 198.12m (650feet)	underground shaft, weapons development			Venting detected, 10Ci		Simultaneous, same hole.	- ! Portola-Larkin - 2	15:30:00.16	PST (–8 hrs)	NTS Area U10bb 37.1784°N -116.0524°W	1285m (4,216feet) – 274m (899feet)	underground shaft, weapons development			Venting detected		Simultaneous, same hole.	- ! Teleme	16:13:00.17	PST (–8 hrs)	NTS Area U9cl 37.1142°N -116.0217°W	1300m (4,300feet) – 304.8m (1,000feet)	underground shaft, weapons development						- ! Bilge	20:10:00.224	PST (–8 hrs)	NTS Area U3kc 37.0022°N -116.0253°W	1179m (3,868feet) – 318.35m (1,044.46feet)	underground shaft, weapons development			Venting detected			- ! Topgallant	16:15:00.09	PST (–8 hrs)	NTS Area U4e 37.1062°N -116.0571°W	1245m (4,085feet) – 713.37m (2,340.45feet)	underground shaft, weapons development						- ! Cabrillo	16:00:00.169	PST (–8 hrs)	NTS Area U2dr 37.134°N -116.0852°W	1288m (4,226feet) – 600.46m (1,970.01feet)	underground shaft, weapons development			Venting detected, 11Ci			- ! Dining Car	19:45:00.187	PST (–8 hrs)	NTS Area U12e.18 37.1879°N -116.2148°W	2238m (7,343feet) – 383.01m (1,256.59feet)	tunnel, weapon effect						- ! Edam	14:10:00.17	PST (–8 hrs)	NTS Area U2dy 37.1157°N -116.0881°W	1272m (4,173feet) – 411.48m (1,350feet)	underground shaft, weapons development						- ! Obar	15:00:00.9	PST (–8 hrs)	NTS Area U7ag 37.1088°N -116.0297°W	1279m (4,196feet) – 568.8m (1,866.1feet)	underground shaft, weapons development						- ! Tybo	14:00:00.16	PST (–8 hrs)	NTS Area U20y 37.2207°N -116.4753°W	1880m (6,170feet) – 765.05m (2,510.01feet)	underground shaft, weapons development						- ! Stilton	14:20:00.17	PST (–8 hrs)	NTS Area U20p 37.34°N -116.5238°W	1667m (5,469feet) – 731.52m (2,400feet)	underground shaft, weapons development						- ! Mizzen	14:40:00.106	PST (–8 hrs)	NTS Area U7ah 37.0948°N -116.037°W	1247m (4,091feet) – 637.18m (2,090.49feet)	underground shaft, weapons development						- ! Alviso	13:00:00.167	PST (–8 hrs)	NTS Area U2du 37.1117°N -116.0746°W	1261m (4,137feet) – 183m (600feet)	underground shaft, safety experiment						- ! Futtock	11:49:00.092	PST (–8 hrs)	NTS Area U3eh 37.0656°N -116.0227°W	1221m (4,006feet) – 186.56m (612.07feet)	underground shaft, safety experiment						- ! Mast	13:00:00.09	PST (–8 hrs)	NTS Area U19u 37.3503°N -116.3211°W	2068m (6,785feet) – 910.7m (2,987.9feet)	underground shaft, weapons development						- ! Camembert	12:30:00.161	PST (–8 hrs)	NTS Area U19q 37.2789°N -116.3695°W	2033m (6,670feet) – 1310.64m (4,300feet)	underground shaft, weapons development

Notes and References

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". Web site: V. N.. Mikhailov. Catalog of World Wide Nuclear Testing. Begell-Atom. dead. https://web.archive.org/web/20140426102201/http://www.iss-atom.ru/ksenia/catal_nt/1.htm. April 26, 2014.
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.
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. Historical time zone data obtained from the IANA time zone database.
Web site: Time Zone Historical Database. iana.com. March 8, 2014.
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.
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.
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.
Include weapons development, weapon effects, safety test, transport safety test, war, science, joint verification and industrial/peaceful, which may be further broken down.
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.
Estimated energy yield in tons, kilotons, and megatons. A ton of TNT equivalent is defined as 4.184 gigajoules (1 gigacalorie).
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.