Seabed caverns and nuclear fracking

How British scientists pondered the “peaceful uses of nuclear explosives”

For a decade from 1969, experts in the United Kingdom researched what they called the ‘peaceful uses of nuclear explosives’. The project, based at the Atomic Weapons Research Establishment at Aldermaston, was never a large one, indeed the annual resources devoted to it never exceeded three person-years, but it does reveal the outer boundaries of what was considered to be feasible and perhaps justifiable.

The investment in expertise in peaceful detonations of nuclear devices was needed, argued the project’s proponents, so that the UK Atomic Energy Authority would be able to assess other countries’ plans. The immediate need might be to analyse, in a critical and informed way, such plans, as well as offer advice on demand to industry. But the door was left open to the possibility that the UK might be involved in these jaw-dropping schemes. Expertise to understand could thus morph into expertise to carry out…

Here’s two plans watched carefully by the Aldermaston team.

The first seems to have been a French proposal originally.  North sea oil, it was suggested, might be stored in a ‘seabed cavern’ formed by a nuclear detonation. ‘Although in this densely-populated country the use of PNE [Peaceful uses of Nuclear Explosions] was improbable, the technique might be proposed for use by other countries for, say, the seabed cavern storage of North Sea oils’, summarised one of the Aldermaston scientists, ‘In that event, the availability of expert UK advice or opposition could be important’. The French spent 60 million francs (about £5 million pounds) investigating such a project, many times the scale of any UK interest. But the French, via a panel meeting of the International Atomic Energy Authority (IAEA), did sound out the UK informally on the possibility of co-operation:

In discussing the use of PNE for North Sea oil storage – at the field, close inshore or on land – the French expressed the view that any project would have to be an international one, possibly involving most of the littoral States. They expressed themselves eager to co-operate in such a scheme, particularly with the UK, and are prepared to enter formal or informal discussions at any level.

The Scottish Office and the Department of Trade and Industry also asked the Aldermaston team for similar advice, and a report, “Cheap oil storage beneath the bed of the North Sea in cavities/chimneys created by contained nuclear explosions”, was written. In fact a ‘site on one of the uninhabited islands of the Shetlands’ was even identified as the ‘best immediate prospect for PNE’.

For a while momentum seemed to be gathering. PNE might not only be used to form vast spaces for storage but also be used to stimulate the flow of hydrocarbons – a form of nuclear fracking, if you like. The Russians reported that they had successfully operated a gas condensate storage unit ‘created by a 15 kton contained nuclear explosion’ in a salt dome. However, by 1973 other investigations, ironically also from within the nuclear state, poured cold water on the scheme: ‘PNE would be uneconomic in shallow, offshore waters simply due to the small size of the storage market’ – although perhaps the project might return in the 1980s as deeper waters were explored and the market had further grown.

When not studying other countries’ schemes, the Aldermaston scientists busied themselves on subsidiary research: estimating the production of radioactivity, predicting fallout patterns and investigating methods of ‘reducing eventual hazards to consumers’. They also assisted the Foreign and Commonwealth Office in thinking through the consequences of a Comprehensive Test Ban regime.

The second project examined closely by the Aldermaston team was an American one called PACER, proposed by Los Alamos and the consultants R&D Associates. A spherical cavity some 200m in diameter would be leached out of a salt dome nearly a mile underground. The giant hole would be filled with a million tons of water. Then a 50 kiloton thermonuclear device would be detonated, producing immense quantities of high pressure steam, which in turn would drive turbines powerfully enough to produce 2000 MW of electricity. And this process would be repeated 750 times a year. Read that last sentence again.

The quick appraisal of PACER produced by an Aldermaston scientist is remarkably matter of fact. The construction of the cavity presented no ‘insuperable difficulty’. Even when the scale of the detonation is discussed – 30,000 explosions over a 40 year life span, all in one hole in the ground – the ‘big technical uncertainty’ of stability only provoked a deadpan note that any ‘failure would have a catastrophic effect on the economics’. But the production of explosives was deemed eminently feasible: the ‘United States has deployed 7000 tactical nuclear weapons in Europe since the mid-fifties and so they could clearly produce 750 50 kton explosives of one type per year’.

And if the United States could do it, how about the United Kingdom? ‘The first step in ascertaining whether PACER is of interest to the United Kingdom’, concluded Parker, ‘could be to survey the salt formations which occur in and around the British Isles’. And if they did occur, why not? ‘The sponsors of this project appear to believe that public acceptance is the major obstacle’. Indeed.

Source: The National Archives, AB 48/1777, 1973-1979. Record opening date: 6 February 2015