Sellafield’s Magnox reprocessing to overshoot promised closure date by four years, says NDA

Atomgjenvinningsanlegget Sellafield i England har i flere år sluppet ut det radioaktive stoffet Tc-99, som har forurenset Nordsjøen. Disse utslippene stoppet i 2004, men fremdeles er det mye radioaktivt materiale lagret ved anlegget.
Foto: Bellona

Publish date: March 20, 2008

Written by: Charles Digges

In a disappointing development for environmentalists, Britain’s Nuclear Decommissioning Authority (NDA) pushed back the cessation of Magnox fuel reprocessing at Sellafield by four years in its Thursday publication of the eighth edition of the Magnox Operation Programme.

Consequently, four of Britain’s Magnox reactors will also remain in operation for the foreseeable future, producing more fuel that needs to be disposed of.

The publication of the decision to delay shutdown of reprocessing Magnox fuel at Sellafield comes less than a week after THORP, another Sellafield reprocessing site, got a government green light to restart operations in the absence of a crucial government safety certificate.

THORP had been closed since 2005 when a leak of plutonium, uranium and nitric acid was discovered to have been leaking undetected for eight months into the facility’s concrete containment shell.

Both the storage of Magnox fuel – which is composed of uranium metal as opposed to more traditional ceramic uranium oxide – and its reprocessing have been of environmental concern for years because of discharges of the radioactive substance Techeium-99 (Tc-99) into the Irish Sea.

The dumping problem was largely solved by adding Tetraphenylphosphonium bromide (TPP) to liquid waste emissions from Sellafield’s Magnox fuel reprocessing plant, slashing tc-99 discharges into the Irish Sea by 95 to 98 percent. But getting the British government to even consider using this technology was an uphill battle for 10 years.

And though Britain has managed to shut down 22 of it’s 26 Magnox reactors – all of which were built between 1960 and 1970 and are thus well beyond their engineered life spans – the closures have been delayed in fits and starts.

More setbacks in clean up
Bellona’s nuclear physicist Nils Bøhmer said that pushing back the closure of Magnox reprocessing facility at Sellafield from 2012 to 2016 is yet another setback in the drumbeat of delays and missed target dates in Britain’s nuclear clean up schedule.

The delay also implies that fuel from closed and still operating Magnox reactors has the potential of further being held in wet storage – a less than ideal method of storing this particular sort of fuel due to the high potential of corrosion of metallic uranium.

The decay of metallic uranium while stored in water produces uranium oxide and uranium hydride, both of which are flammable.

“The delay in stopping reprocessing in England once again highlights that reprocessing must be stopped and that they have to find other solutions for their nuclear waste,” said Bøhmer.

NDA says 2012 shutdown date was tentative
The NDA has justified the prolongation of Magnox reprocessing by indicating in its Magnox Operation Programme that the 2012 shutdown date was tentative because it assumed the Magnox reprocessing facility would meet its target throughput of 1,000 tons of waste per year without a hitch.

But in the two years following that commitment, which was made by BNFL in 2000, the facility was already lagging behind, having reprocessed 1,600 of the 2,000 projected tons of waste. The sharpest drop occurred in 2001 when the facility reprocessed only 600 tons of fuel.

Yet the NDA remained sanguine in its almost casual announcement of the four-year delay on page seven of the new 56-page Magnox document, noting that the Tc-99 abatement process was still a success.

“Subsequent work to implement Technetium 99 (Tc99) abatement means that, despite the later end date, the reprocessing sector targets in the UK discharge plan can still be met,” the report read.

The report notes that “improvement plans are being prepared and enacted to pull the end date (of Magnox reprocessing) forward.

In an ironic twist, though, the report notes that the additional years that the four remaining Magnox reactors are to be in operation will provide revenue to the NDA in its clean up efforts.

This is not the first instance in which the NDA has sought to fund itself by operating the very facilities it seeks to close. THORP was a financial albatross for the NDA in the three years it was shut down, reliant as the agency is on much of the revenues from foreign reprocessing customers sending their waste to the plant.
Thus, while the NDA earmarks the bulk of its funding for clean up at Sellafield, it is reliant in part on those funds generated by Sellafield operations.

Years to implement even simple clean up solutions
The considerable advances in dealing with waste products from Magnox reprocessing are not, according Bøhmer, ultimately the point, but rather the consistent pattern of delays in Britain’s nuclear clean up projects, facilitated in part by the NDA’s financial dependence on those facilities it is to shut down.

Even the decision to use TPP in cleansing the plant’s regular discharges into the Irish Sea – which for years provoked the ire of Ireland and Norway – took a decade of environmental brinksmanship led by Bellona to be realised.

New nuclear build promised more waste before solutions

Now that Britain in standing on the precipice of an enormous nuclear build up that will pile new waste on top of the old, noted Bøhmer, the UK government is making only small steps toward heading off a radioactive pile up.

The cost overruns for cleaning up what is already there have already exceeded projections by billions of pounds.

A recent decision of the UK government – well after announcing its backing for nuclear power to alleviate CO2 emissions – was the requirement that nuclear plant contractors include in proposals waste storage methods.

The UK government is also looking into deep geologic storage of highly radioactive waste with the help of Sweden. But realising this technology could take several decades beyond when Britain’s nuclear waste problem reaches critical mass.