U.S. program examining the peaceful applications of nuclear explosives (1961–77)
This article is about proposed peaceful uses of nuclear weapons. For the serialized Philip K. Dick novel with the same name, see The Zap Gun. For the Christian anti-nuclear protest movement, see Plowshares Movement.
Project Plowshare was the overall United States program for the development of techniques to use nuclear explosives for peaceful construction purposes. The program was organized in June 1957 as part of the worldwide Atoms for Peace efforts. As part of the program, 35[1] nuclear warheads were detonated in 27 separate tests. A similar program was carried out in the Soviet Union under the name Nuclear Explosions for the National Economy, although the Soviet program consisted of 124 tests.
The project's uncharacteristically large and atmospherically vented Sedan nuclear test also led geologists to determine that Barringer crater was formed as a result of a meteor impact and not from a volcanic eruption, as had earlier been assumed. This became the first crater on Earth definitely proven to be from an impact event.[5]
Negative impacts from Project Plowshare's tests generated significant public opposition, which eventually led to the program's termination in 1977.[6] These consequences included tritiated water (projected to increase by CER Geonuclear Corporation to a level of 2% of the then-maximum level for drinking water)[7] and the deposition of fallout from radioactive material being injected into the atmosphere before underground testing was mandated by treaty.
Rationale
By exploiting the peaceful uses of the "friendly atom" in medical applications, earth removal, and later in nuclear power plants, the nuclear industry and government sought to allay public fears about nuclear technology and promote the acceptance of nuclear weapons.[8] At the peak of the Atomic Age, the United States Federal government initiated Project Plowshare, involving "peaceful nuclear explosions". The United States Atomic Energy Commission chairman at the time, Lewis Strauss, announced that the Plowshares project was intended to "highlight the peaceful applications of nuclear explosive devices and thereby create a climate of world opinion that is more favorable to weapons development and tests".[9][10][need quotation to verify] These tests were to demonstrate that atomic bombs can be used for peaceful purposes, that the atomic sword could be beaten into a plowshare.
Proposals
Proposed uses for nuclear explosives under Project Plowshare included widening the Panama Canal, constructing a new sea-level waterway through Nicaragua nicknamed the Pan-Atomic Canal, cutting paths through mountainous areas for highways, and connecting inland river systems. Other proposals involved blasting caverns for water, natural gas, and petroleum storage. Serious consideration was also given to using these explosives for various mining operations. One proposal suggested using nuclear blasts to connect underground aquifers in Arizona. Another plan involved surface blasting on the western slope of California's Sacramento Valley for a water transport project.[6]
One of the first serious cratering proposals that came close to being carried out was Project Chariot, which would have used several hydrogen bombs to create an artificial harbor at Cape Thompson, Alaska. It was never carried out due to concerns for the native populations and the fact that there was little potential use for the harbor to justify its risk and expense.[11]
A project proposed in a 1963 memorandum by Lawrence Livermore National Laboratory would have used 520 2-megaton nuclear explosions to excavate a canal through the Negev Desert in Israel at an estimated cost of $575 million ($5 billion in 2021), to serve as an alternative route to the Suez Canal.[13][14]
At the end of the program, a major objective was to develop nuclear explosives, and blast techniques, for stimulating the flow of natural gas in "tight" underground reservoir formations. In the 1960s, a proposal was suggested for a modified in situshale oil extraction process which involved creation of a rubble chimney (a zone in the oil shale formation created by breaking the rock into fragments) using a nuclear explosive.[15] However, this approach was abandoned for a number of technical reasons.
Plowshare testing
The first Peaceful Nuclear Explosion (PNE) blast was Project Gnome, conducted on December 10, 1961, in a salt bed 24 mi (39 km) southeast of Carlsbad, in southeast New Mexico. The explosion released 3.1 kilotons (13 TJ) of energy yield at a depth of 1,184 ft (361 m) which resulted in the formation of a 170 ft (52 m) diameter, 80 ft (24 m) high cavity. The test had many objectives, the most public of which involved the generation of steam which could then be used to generate electricity. Another objective was the production of useful radioisotopes and their recovery. Yet another experiment involved neutrontime-of-flightphysics, and a fourth experiment involved geophysical studies based upon the timed seismic source. Only the last objective was considered a complete success. The blast unintentionally vented radioactive steam while the press watched. The partly developed Project Coach detonation experiment that was to follow adjacent to the Gnome test was then canceled.
A number of proof-of-concept cratering blasts were conducted; including the Buggy shot of five 1-kiloton devices for a channel/trench in Area 30 and the largest being 104 kiloton (435 terajoule) on July 6, 1962, at the north end of Yucca Flats, within the Atomic Energy Commission's Nevada Test Site (NTS) in southern Nevada. The shot, "Sedan", displaced more than 12 million short tons (11,000 million kilograms) of soil and resulted in a radioactive cloud that rose to an altitude of 12,000 ft (3.7 km). The radioactive dust plume headed northeast and then east towards the Mississippi River.[6]
Over the next 11 years, 26 more nuclear explosion tests were conducted under the United States PNE program. The radioactive blast debris from 839 U.S. underground nuclear test explosions remain buried in-place and have been judged impractical to remove by the DOE's Nevada Site Office. Funding quietly ended in 1997, and costs for the program have been estimated at more than (US) $770 million.[6]
The final PNE blast took place on May 17, 1973, under Fawn Creek, 47.5 mi (76.4 km) north of Grand Junction, Colorado. Three 30-kiloton detonations took place simultaneously at depths of 5,768, 6,152 and 6,611 ft (1,758, 1,875 and 2,015 m). If it had been successful, plans called for the use of hundreds of specialized nuclear explosives in the western Rockies gas fields. The previous two tests had indicated that the produced natural gas would be too radioactive for safe use; the Rio Blanco test found that the three blast cavities had not connected as hoped, and the resulting gas still contained unacceptable levels of radionuclides.[17]
By 1974, approximately $82 million had been invested in the nuclear gas stimulation technology program. It was estimated that even after 25 years of production of all the natural gas deemed recoverable, only 15 to 40% of the investment would be recouped. Also, the concept that stove burners in California might soon emit trace amounts of blast radionuclides into family homes did not sit well with the general public. The contaminated gas was never channeled into commercial supply lines.
The situation remained so for the next three decades, but a resurgence in Colorado Western slope natural gas drilling has brought resource development closer and closer to the original underground detonations. By mid-2009, 84 drilling permits had been issued within a 3-mile (4.8 km) radius, with 11 permits within one mi (1.6 km) mile of the site.[18]
Impacts, opposition and economics
Operation Plowshare "started with great expectations and high hopes". Planners believed that the projects could be completed safely, but there was less confidence that they could be completed more economically than conventional methods. Moreover, there was insufficient public and Congressional support for the projects. Projects Chariot and Coach were two examples where technical problems and environmental concerns prompted further feasibility studies which took several years, and each project was eventually canceled.[2]
Citizen groups voiced concerns and opposition to some of the Plowshare tests. There were concerns that the blast effects from the Schooner explosion could dry up active wells or trigger an earthquake. There was opposition to both Rulison and Rio Blanco tests because of possible radioactive gas flaring operations and other environmental hazards.[2] In a 1973 article, Time used the term "Project Dubious" to describe Operation Plowshare.[17]
There were negative impacts from several of Project Plowshare’s 27 nuclear explosions, primarily those conducted in the project's infancy and those that were very high in explosive yield.
Project Gnome vented radioactive steam over the very press gallery that was called to confirm its safety. The next blast, a 104-kiloton detonation at Yucca Flat, Nevada, displaced 12 million tons of soil and resulted in a radioactive dust cloud that rose 12,000 feet [3,700 m] and plumed toward the Mississippi River. Other consequences – blighted land, relocated communities, tritium-contaminated water, radioactivity, and fallout from debris being hurled high into the atmosphere – were ignored and downplayed until the program was terminated in 1977, due in large part to public opposition.[6]
Project Plowshare shows how something intended to improve national security can unwittingly do the opposite if it fails to fully consider the social, political, and environmental consequences. It also “underscores that public resentment and opposition can stop projects in their tracks”.[6]
The social scientistBenjamin Sovacool contends that the main problem with oil and gas stimulation, which many considered the most promising economic use of nuclear detonations, was that the produced oil and gas was radioactive, which caused consumers to reject it and this was ultimately the program's downfall.[6] Oil and gas are sometimes naturally radioactive to begin with, however, and the industry is set up to deal with oil and gas that contain radioactive contaminants.[19] Historian Dr. Michael Payne notes that it was primarily changing public opinion, in response to events such as the Cuban Missile Crisis, that drove the protests,[20] court cases and general hostility that ended the oil and gas stimulation efforts. Furthermore, as the years went by without further development and production of nuclear weapons slowed, interest in peaceful applications waned in the 1950s–60s. Cheaper, non-nuclear stimulation techniques suitable for most US gas fields were developed in the following years.[21][22]
As a point of comparison, the most successful and profitable nuclear stimulation effort that did not result in customer product contamination issues was the 1976 Project Neva on the Sredne-Botuobinsk gas field in the Soviet Union, made possible by multiple cleaner stimulation explosives, favorable rock strata and the possible creation of an underground contaminant storage cavity.[23][24] The Soviet Union retains the record for the cleanest/lowest fission-fraction nuclear devices so far demonstrated.
The public records for devices that produced the highest proportion of their yield via fusion-only reactions, and therefore created orders of magnitude smaller amounts of long-lived fission products as a result, are the USSR's Peaceful nuclear explosions of the 1970s, with the three detonations that excavated part of Pechora–Kama Canal, being cited as 98% fusion each in the Taiga test's three 15-kiloton explosive yield devices, that is, a total fission fraction of 0.3 kilotons in a 15 kt device.[25] In comparison, the next three high fusion-yielding devices were all much too high in total explosive yield for oil and gas stimulation: the 50-megaton Tsar Bomba achieved a yield 97% derived from fusion,[26] while in the US, the 9.3-megaton Hardtack Poplar test is reported as 95.2%,[27] and the 4.5-megaton Redwing Navajo test as 95% derived from fusion.[28]
Nuclear tests
The U.S. conducted 27 PNE shots in conjunction with other, weapons-related, test series.[2] A report by the Federation of American Scientists includes yields slightly different from those presented below.[29]
A multipurpose experiment designed to provide data concerning: (1) heat generated from a nuclear explosion; (2) isotopes production; (3) neutron physics; (4) seismic measurements in a salt medium; and (5) design data for developing nuclear devices specifically for peaceful uses.
An excavation experiment in alluvium to determine feasibility of using nuclear explosions for large excavation projects, such as harbors and canals; provide data on crater size, radiological safety, seismic effects, and air blast.
An excavation experiment to explore cratering mechanics in hard, dry rock and study dispersion patterns of airborne radionuclides released under these conditions.
A gas stimulation experiment to investigate the feasibility of using nuclear explosives to stimulate a low-permeability gas field; first Plowshare joint government-industry nuclear experiment to evaluate an industrial application.
An excavation experiment to explore cratering mechanics in hard, dry rock and study dispersion patterns of airborne radionuclides released under these conditions.
A gas stimulation experiment to investigate the feasibility of using nuclear explosives to stimulate a low-permeability gas field; provide engineering data on the use of nuclear explosions for gas stimulation; on changes in gas production and recovery rates; and on techniques to reduce the radioactive contamination to the gas.
Flask -Green, -Yellow, -Red
May 26, 1970
Nevada Test Site
Shaft
Green, 1736 ft (529.2 m); Yellow, 1,099 ft (335 m); Red, 499 ft (152.1 m)
A gas stimulation experiment to investigate the feasibility of using nuclear explosives to stimulate a low-permeability gas field; develop technology for recovering natural gas from reservoirs with very low permeability.
Non-nuclear tests
In addition to the nuclear tests, Plowshare executed a number of non-nuclear test projects in an attempt to learn more about how the nuclear explosives could best be used. Several of these projects led to practical utility as well as to furthering knowledge about large explosives. These projects included:[2]
Test name
Date
Location
Type
Depth of Burial
Medium
Yield
Note
Pre-Gnome
February 10–16, 1959
Southeast of Carlsbad, New Mexico
seismic experiment (High explosive)
1,200 ft (365.8 m), each
Bedded salt
3.65 tons
Three seismic experiments to measure ground shock for the planned GNOME nuclear test.
Toboggan
November–December 1959 & April–June 1960
Nevada Test Site
ditching experiment (High explosive, TNT)
3 to 20 ft (1 to 6.1 m)
Playa (combination of silt and clay)
Series of 122 detonations of both linear and point HE charges
Study ditching characteristics of both-end detonated and multidetonated HE explosives in preparation for nuclear row charge experiments.
Hobo
February–April 1960
Nevada Test Site
seismic experiment (High explosive, TNT)
Unknown
Tuff
Three explosions, varying from 500 to 1,000 lb. charges each
To study rock fracturing and related phenomena produced by contained explosions.
Stagecoach
March 1960
Nevada Test Site
excavation experiment (High explosive, TNT)
Shot 1 – 80 ft (24.4 m); Shot 2 17.1 ft (5.2 m); Shot 3 – 34.2 ft (10.4 m)
Alluvium
Three 40,000 lb. charges
Examine blast, seismic effects and throw out characteristics in preparation for nuclear cratering experiments.
To study crater dimension, throw out material distribution, ground motion, dust cloud growth, and long-range air blast.
Initially scheduled for July,[31] the shot was delayed due to the accidental use of dummy detonators. As the detonators had to be placed in the center of the charge, organizers were required to dig down to the TNT charge and then use a steam heated mandrel to melt to its center, an extremely hazardous process.[32]
Rowboat
June 1961
Nevada Test Site
row-charge experiment (High explosive, TNT)
Varied
Alluvium
8 detonations of series of four 278 lb. charges
To study the effects of depth of burial and charge separation on crater dimensions.
Yo-Yo
Summer 1961
At LRL, near Tracy, California
simulated excavation experiment (High explosive)
Varied
Oil-sand mixture
100 gm charges
To develop estimates for the quantities of radiation released to the atmosphere by a cratering detonation.
Pre-Gondola I, four 20-ton charges; Pre-Gondola II, row of five charges totaling 140 tons; Pre-Gondola III, Phase I, three rows of seven one-ton charges; Phase II, one row of seven 30- ton charges; Phase III, one row of five charges varying from five to 35 tons and totaling 70 tons
U.S. Army Corps of Engineers project to provide seismic calibration test data and cratering characteristics for excavation projects.
Excavation of three miles of a divide cut through low hills; connect Tennessee and Tombigee rivers; dig 250-mile long canal.
Interoceanic Sea-Level Canal Study
1965–70
Pan-American Isthmus (Central America)
Commission appointed in 1965 to conduct feasibility studies of several sea-level routes for an Atlantic- Pacific interoceanic canal. Two routes were in Panama and one in northwestern Colombia. The 1970 final report recommended, in part, that no current U.S. canal policy should be made on the basis that nuclear excavation technology will be available for canal construction. AEC deferred in making any decision.
Flivver
Mar. 1966
Nevada Test Site
A low-yield cratering detonation to study basic cratering phenomenology.
Dragon Trail
Dec. 1966
Rio Blanco County, CO
Natural gas stimulation experiment; different geological characteristics than either GASBUGGY or RULISON; geological study completed.
First discussed with U.S. officials in 1962, the U.S. formally agreed to participate in a joint feasibility study with the Australian government in early 1969 for using nuclear explosives to construct a harbor. The project was stopped in March 1969 when it was determined that there was an insufficient economic basis to proceed.
Yawl
1969–70
Nevada Test Site
Cratering experiment to extend excavation information on yields and rock types relevant to the trans-Isthmian canal.
Geothermal Power Plant
1971
Not determined
Geothermal resource experiment; fracturing would allow fluids circulated in fracture zones to be converted to steam to generate electricity.[2]
^"Archived copy". www.ociw.edu. Archived from the original on February 10, 2006. Retrieved January 12, 2022.{{cite web}}: CS1 maint: archived copy as title (link)
^"semiannual report to Congress in January 1958". Other mentions of Strauss making statements in Feb 1958 or hearings being held are on p 447, and 474 it seems. p. 474's quotation: Senate Subcommittee of the Committee on Foreign Relations, Hearings on Control and Reduction of Armaments, Feb. 28 – April 17, 1958, Washington: Government Printing Office, 1958) pp. 1336–1364.
^Carothers, J (June 1995). Caging the dragon: the containment of underground nuclear explosions (Report). USDOE Nevada Operations Office, Las Vegas, NV (United States); Defense Nuclear Agency, Alexandria, VA (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). pp. 65–68. OSTI524871. DOE/NV-388; DNA-TR-95-74; DE98000017.
Kirsch, Scott (2005), Proving Grounds: Project Plowshare and the Unrealized Dream of Nuclear Earthmoving, New Brunswick, NJ and London: Rutgers University Press.
Miller, Richard L (1999), Under the Cloud: The Decades of Nuclear Testing, Woodlands, TX: Two Sixty Press, ISBN1-881043-05-3.
"Executive Summary", Estimated Exposures and Thyroid Doses Received by the American People from Iodine-131 in Fallout Following Nevada Atmospheric Nuclear Bomb Tests (report), National Cancer Institute, 1999, Figure 1 – Per capita thyroid doses resulting from all exposure routes from all test.
"Plowshare", NV(PDF), US: DOE, archived from the original(PDF) on September 7, 2006, Declassification of the yields of 11 nuclear tests conducted as part of the plowshare... program.
"Plowshare Program", Atomic traveler(PDF) (chronology) milestones, including proposed tests and projects conducted.