THE MOST notorious places are often the most dismal. Aldermaston, the secretive citadel that gave Britain its nuclear weapons, is not a sight to lift the heart. As far as the eye can see there are drab buildings and bunkers, set in a sea of mud and grass. A huge, ancient heating pipe snakes around them, leaking steam. Beyond lie rank after rank of imposing barbed-wire fences. The sense is one of decay and glories past.
Aldermaston’s real problems, however, cannot be seen. The site has been making and maintaining nuclear bombs for the past 52 years. Driven by the ruthless logic of the cold war and unencumbered by today’s safety regulations, this has left a daunting legacy of pollution and waste whose scale is only just starting to be understood. Large areas of soil and groundwater are contaminated, thousands of drums of plutonium leftovers are piling up, and an ancient underground pipeline to the river Thames is lined with radioactive scale.
But Jonathan Brown, an enthusiastic chemical engineer who leads Aldermaston’s two-year-old clean-up programme, is undaunted. “Overall, Aldermaston is a very clean site,” he insists. Even so, he reckons cleaning up Aldermaston and the neighbouring weapons assembly plant at Burghfield will take 70 years and cost around £2 billion of public money.
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Huge though that figure is, Aldermaston is only a small part of a much bigger problem. To clean up its entire nuclear weapons programme, Britain will have to treat and store thousands of tonnes of radioactive waste and decontaminate up to 50 military sites. And on top of the nuclear weapons, some way will have to be found to deal with the nuclear reactors from 27 obsolete submarines. The government estimates the total cost at £30 billion, all of which will have to come from the public purse. It’s a figure that puts the dirty legacy of Britain’s nuclear weapons on a par with that of its nuclear energy programme, which has accumulated £34 billion worth of civil liabilities.
But in reality, things may even be worse. The cost estimates for Aldermaston are tentative at best, and the clean-up programme there has got off to a shaky start, dogged by delays, hampered by a dearth of documentary evidence and criticised by regulators. If the entire operation suffers the same level of uncertainty-and the record of Britain’s other military nuclear facilities hardly inspires confidence-then Britain’s weapons legacy will end up costing even more than its nuclear energy clean-up.
Aldermaston covers 2.7 square kilometres of rural Berkshire between Reading and Basingstoke. The site, now run by a consortium of private companies known as the Atomic Weapons Establishment (AWE), has always been a focus for protesters horrified by its awesome capacity for destruction. Insiders, however, bristle with pride at its achievements. Visitors are treated to a short laptop presentation boasting about the skill and dedication of the scientists who successfully exploded Britain’s first fission bomb at the Montebello Islands off Australia in 1952, and then the nation’s first fusion bomb, near Christmas Island in the Pacific in 1957.
These days, Aldermaston’s main mission is to service the stock of 200 warheads for Britain’s four Trident submarines. It also has to maintain the capability to develop replacement warheads should the government want them.
For the past two years, it has had another mission: cleaning up the huge radioactive and chemical mess it has made. AWE scientists characterise the problem in comforting terms. “Levels of environmental contamination are very low, and we are now focusing on a small number of locations where some remediation action may be appropriate,” says Brown. Outsiders are less reassuring. “They have a really terrible problem,” says Christine Bruce, a Ministry of Defence (MoD) radiation protection adviser at the Rosyth naval dockyard near Edinburgh. “Their site is large and dirty.” It’s hard to fathom which version is closer to the truth. No one really knows the scale of the problem, and even the waste that is known about isn’t proving easy to sort out.
A series of secret documents leaked to 91av graphically illustrate the problem AWE scientists face. They include records of a tetchy exchange of emails between AWE officials in 1998, which reveals an embarrassing predicament with five safes, thought to contain “various uranium solutions”. No one could remember, or had any records of, the combination numbers that would open them. The safes were being stored along with other defunct equipment in an area called Steels Yard, which was being cleared. “There is no known history to the vast majority of the gear,” wrote AWE’s Chris Bonsey. “I understand that most, if not all, are items that have been collected externally and have been open to the elements and personnel for many months/years.”
Bonsey was advised by a colleague that, as the safes were probably empty, it should not be dangerous to drill the locks, as long as the interiors were tested for contamination as they were opened. Unfortunately, what actually happened when they opened the safes is not recorded.
Aldermaston’s managers dismiss suggestions that such problems still exist. “I’m not aware of any items of which we don’t know the history,” says George Wall, AWE’s environment director. “There are no vast compounds of unidentified waste.” The official line is that, altogether, 2500 cubic metres of medium-level waste is stored in 13,000 drums on the site.
But a second leaked document paints a different picture. Before the AWE was awarded the current contract to run the site for the MoD in April 2000, one of its members, British Nuclear Fuels (BNFL), expressed concern that contamination and waste had been underestimated (91av, 29 April 2000, p 5). A leaked BNFL document from the time said: “Until comprehensive surveys have been completed, the potential extent of the problem will be unclear. There may be accumulations of wastes, both radioactive and toxic, in buildings on the sites that are not included in any identified inventory.” Two years on, the scale of the contamination at Aldermaston is still not known. So far only 30 per cent of the site-the parts scientists think are the most heavily polluted-has been surveyed.
The surveys point to a long and difficult clean-up operation. A map produced by AWE shows nine separate areas of contamination covering about 200 acres in total. In most of these areas, AWE is carrying out further assessments. What’s more, an as yet unpublished study by Southampton University found low-level contamination outside the site.
The map shows that in two areas the sediment is laced with plutonium, and in one of these levels of radioactivity were measured at around 500 becquerels per gram of sediment, where none would be expected to occur naturally.
In another two areas the groundwater and soil have been contaminated with tritium, a radioactive isotope of hydrogen used in fusion bombs. Levels are up to 20 times that of natural levels. AWE says the source of the contamination remains a mystery. In the remaining five areas, the soil and groundwater have been poisoned with hazardous solvents such as trichloroethane and trichloromethane, plus oil and mercury, sometimes in breach of safety limits. In one area a new filtration plant has been installed to protect the groundwater.
The problems haven’t escaped the notice of regulators. Last year the government’s Radioactive Waste Management Advisory Committee warned AWE not to drag its heels. “Better characterisation of site contamination… is a clear and urgent task,” the committee concluded. And in June the Nuclear Installations Inspectorate (NII) was “disturbed” to learn that proposals for treating radioactive wastes resulting from the purifying of plutonium for warheads had been indefinitely postponed in order to save money. According to Brown, this is now unlikely to begin before 2006. The NII also expressed concern about “infringements” of the rules for storing plutonium and uranium safely. This has happened 16 times over the past three years, though the AWE insists that none of the breaches led to “an unsafe situation”.
With only 10 to 20 per cent of AWE’s resources devoted to clean-up operations, according to Wall, and new problems cropping up all the time, the programme is slipping further and further behind schedule. Medium-level radioactive waste in one old store, which Brown had planned to transfer to new stores before the end of this year, will remain where it is because efforts have had to be diverted to tackling another problem. NII is insisting that radioactive sludge kept in 20 ageing tanks has to be treated, removed and re-stored, after one of the tanks sprang a leak in July 2000.
Perhaps the site’s most awkward legacy is its waste pipeline. Since the early 1950s, millions of litres of liquid radioactive waste have been pumped through a pair of 18-kilometre underground pipes to the village of Pangbourne where it discharges into the River Thames. The pipeline, buried an average of 1.8 metres below ground, goes under a canal, a river, two railway lines, and numerous roads including the A4 and the M4 motorway. In the 1950s and 1960s, says AWE, it was spewing out a hundred times as much radioactivity as it does now.
Over the years a crust of radioactive scale has built up on the inside of the pipe, much as limescale accumulates in a kettle. This now leaches into liquids in the pipe. As a result, the waste that reaches the Thames is 15 to 20 per cent more radioactive than it was when it left Aldermaston.
AWE estimates that the whole pipeline contains about 300 megabecquerels of radioactivity, five times the amount Aldermaston is authorised to discharge from the pipe every year. AWE has been told by the Environment Agency, another regulator, that the pipeline must close by 1 April 2005. AWE is planning to remove some of the radioactivity by pumping through a liquid scourer that would expel much of the radioactive scale. The resulting waste would be pumped backed to Aldermaston and stored in tanks. It then wants to seal off the entrances and exits, and leave the pipeline buried where it is, hidden beneath the English countryside.
It is far from certain, however, that this will prove acceptable to the Environment Agency or the government. Following an initial study by AWE in 2001, the agency is demanding detailed new information so it can assess whether leaving the pipeline in the ground is the best option. Some anti-nuclear campaigners argue that it might be better dug up and stored above ground, where it can be monitored for leaks, though this too has risks. “It is not acceptable to leave 18 kilometres of nuclear waste under Berkshire,” says Di McDonald of the Nuclear Information Service in Southampton.
Beyond Aldermaston, it is defunct nuclear submarines that pose the trickiest problems. There are already seven laid up at Rosyth and another four at the Devonport naval dockyard near Plymouth. Over the next three decades a further 16 are due to come out of service. All of them are powered by reactors fuelled by highly enriched uranium, which has to be removed and sent to Sellafield in Cumbria for long-term storage. The reactor vessel and associated pipework must also be dismantled, extracted and disposed of as radioactive waste.
According to the MoD, a submarine reactor compartment yields 164 tonnes of radioactive waste, making a grand total of nearly 4500 tonnes that will have to be disposed of. The MoD has embarked upon a long and painful consultation process in an attempt to involve the public in deciding what to do with the submarines. But Babcock, the multinational that now runs Rosyth, has jumped the gun by proposing that one of the old Polaris subs, HMS Renown, should be dismantled and its radioactive waste put in store at the dockyard.
This has been rejected by the MoD, although something similar is the most likely outcome of the consultation. Babcock is annoyed: it wants rid of the submarines now clogging up the dockside. “We’re not entirely comfortable with them being here,” says Nick Parish, the company’s scientific services manager. “The site has this perception of being a nuclear graveyard.”
Whatever the outcome of the consultation, it’s hard to be confident that things will go according to plan. Rosyth and Devonport dockyards, along with the submarine bases in the west of Scotland, have already been responsible for one of Britain’s biggest but least known radioactive cock-ups. For three decades they forgot to mention that waste from the submarines’ coolant circuits contained a potentially dangerous radioisotope, carbon-14.
When sending waste to Britain’s only official low-level dump, run by BNFL at Drigg near Sellafield, the MoD is required to specify which isotopes it contains. Although it declared cobalt-60 and tritium, it did not say anything about carbon-14. This was a serious omission: carbon-14, with a half-life of 5730 years, takes tens of thousands of years to decay to harmless levels.
After the oversight was discovered in 1998, BNFL refused to accept any further waste from submarines at Drigg. Since then the waste has had to be stored at the sites where it originated. In an attempt to get the ban lifted, the MoD has worked out how much carbon-14 it sent in the past, though it would not disclose the figure when asked by 91av. BNFL, however, is stalling until it receives the millions of pounds for the carbon-14 it has already unwittingly accepted.
The judgement of the 19 experts on the Radioactive Waste Management Advisory Committee was harsh. “The unsuspected presence of carbon-14,” they conclude, “must be seen to cast serious doubts on the MoD’s credibility as a waste consignor and the adequacy of its internal assurance arrangements.” The MoD, it seems, still has a big hill to climb before it can be trusted to deal with Britain’s cold war legacy.
