Alberta reaction

A month after the Richfield meeting with the AEC, Natland and Richfield executives travelled to Edmonton to meet Alberta's deputy minister of mines and minerals Hubert H. Somerville to discuss the proposal on June 5, 1958, Somerville was supportive of the idea. Somerville relayed the proposal to Premier Ernest Manning who was interested in exploring the concept.^[11] Following the meeting with deputy minister Somerville, Richfield executives met with federal regulators to discuss the proposal. This included staff of the Federal Mines Branch John Convey and Alexander Ignatieff; Donald Watson of Atomic Energy of Canada Limited; and Alexander Longair of the Defence Research Board, which was met with interest from the federal group.^[12]

An investigative committee was formed with the support of Alberta's Social Credit government. One of the committee's early recommendations was that, in order to minimize public fears, a "less effervescent name"^[13] should be used; Project Cauldron was subsequently renamed Project Oilsand.

In April 1959, the Federal Mines Department approved Project Oilsand; Pony Creek, Alberta (103 kilometres [64 miles] from Fort McMurray) was selected as a test site.^[1] Before the project could continue beyond these preliminary steps, however, the Canadian government's stance on the use of nuclear weapons shifted towards one of non-proliferation; out of concerns that it would increase the risk of Soviet espionage, Project Oilsand was put on hiatus.^[1] In April 1962, Canadian Secretary of State for External Affairs Howard Charles Green said "Canada is opposed to nuclear tests, period";^[14] Project Oilsand was subsequently cancelled.

These changes in Canadian public opinion are regarded by historian Michael Payne to be due to the shift in public perception of nuclear explosives following the 1962 Cuban Missile Crisis.^[15] Prime Minister John Diefenbaker told Parliament that the decision to detonate an atomic bomb on or under Canadian soil would be made by Canada, not the United States, and ordered Project Cauldron/Oilsand placed on permanent hold, citing the risk of upsetting the Soviet Union during nuclear disarmament negotiations being conducted in Geneva.^[16]

Social scientist Benjamin Sovacool contends that the main problem was that the produced oil and gas would be radioactive, which would cause consumers to reject it.^[17] In contrast, oil and gas are sometimes considerably naturally radioactive to begin with and the industry is set up to deal with this; moreover. in contrast to earlier stimulation efforts,^[18] contamination from many later tests was not a showstopping issue. Rather, it was primarily changing public opinion due to the societal fears caused by events such as the Cuban Missile Crisis, that resulted in protests,^[19] court cases and general hostility that ended the US exploration. Furthermore, as the years went by without further development and the closing/curtailment in US nuclear weapons factories, this began to evaporate the economies of scale advantage that had earlier existed, with this, it was increasingly found that most US fields could instead be stimulated by non-nuclear techniques which were found to be likely cheaper.^[20][21]

Theoretical background

The general means by which the plan was to work was discussed in the October 1976 Bulletin of the Atomic Scientists issue.^[22] A patent was granted for the process that was intended: The Process for Stimulating Petroliferous Subterranean Formations with Contained Nuclear Explosions by Bray, Knutson, and Coffer which was first submitted in 1964.^[23] With the nuclear detonation option being considered to have served as a forerunner to some of the nascent conventional ideas that are presently in use and proposed to extract oil from the Alberta regions Athabasca oil sands.^[24]

Previous underground nuclear weapon tests by the AEC had provided scientific evidence on the effect on rock surrounding the blast.^[5] Milliseconds following the detonation of the weapon the temperature of the surrounding area would rise exponentially to millions of degrees, vaporizing and melting any surrounded rock which would expand to create an underground cavity lined with molten rock.^[5] The shockwave from the detonation would progress beyond the cavity fracturing rock outside of the cavity, eventually causing liquid parts to drip down below until the cavity pressure and temperature drops resulting in the rock solidifying.^[5] The solidified cavity would contain any radioactive gasses and as pressure drops the overburden collapses under the weight, burying most of the radioactive materials at the bottom of the cavity.^[25]

Project Oilsand methods

For Project Oilsand, the proposed plan had a 9 kt (38 TJ) nuclear device buried 1,250 feet (380 m) underground in the Beaverhill Lake Group, 20 feet (6.1 m) below the base of the McMurray Formation above.^[7] Natland and the AEC believed a 9 kt nuclear device was powerful enough to facilitate a meaningful test and be completely contained at the proposed depth with a "generous safety factor" to ensure radioactive debris could not escape.^[26] The decision to drill to 1,250 feet was based on the safe containment formula developed after the Rainier test where depth in feet is equal to 450 times the energy in kilotons to the power of one-third (D = 450W^1/3).^[26] The Lawrence Livermore National Laboratory considered the formula to be "extremely conservative" due to the resilient overlying Clearwater shale bed, and scientists believed a 30–40 kt (130–170 TJ) nuclear device could be detonated without causing a disruption to the surface, and theorized up to 100 kt (420 TJ) may have been used safely.^[26]

Based on research by the Lawrence Livermore National Laboratory, the cavity created by the detonation was estimated to be approximately 230 feet (70 m) in diameter.^[26] The cavity was expected to collapse anywhere between a few seconds and few minutes following the detonation,^[26] and "several million" cubic feet of oil sand would have fallen into the cavity, the oil separated by the intense heat, allowing recovery through conventional drilling.^[27] Natland also believed that the pressure from the resulting shockwave was sufficient to crack the oil, increasing the total recoverable beyond the thermal effects.^[27]