Photo: Foto: BNFL
BNFL’s discharge permit for the following four years allows the emission of 360 terabequerel (TBq) of technetium-99 (Tc-99). In consequence, British Nuclear Fuels (BNFL), having both the ownership and management responsibility of the Sellafield plant, can dispose its old waste before the discharge permit is being restricted in 2006, at which point there will be little waste left to clean.
The UK violates its commitments
Based on the above, it seems like the British environmental authorities fail to fulfil the North Sea Declaration, even before it has been signed. The British Environment Minister, Michael Meacher, arrives in Bergen on Wednesday to sign the new North Sea Declaration.
The United Kingdom has through the OSPAR Convention already committed to reducing the discharges from Sellafield such that there would be close to ‘zero’ radioactive concentration in the marine environment in 2020. Notwithstanding, does the British environmental directorate, the Environmental Agency (EA), now recommend a permit allowing BNFL to discharge the remaining stored Tc-99 waste into the sea. Thus, the EA has failed on all essential points agreed upon in the so-called Esbjerg Declaration from 1995, which the coming conference in Bergen is a follow-up on. The coming conference in Bergen is a review of the declaration from 1995.
Nuclear pulp
Approximately 2,700 cubic metres of liquid medium-level nuclear waste are stored at the Sellafield plant. As BNFL plans to empty the tanks entirely, almost 600 cubic metres of this liquid waste is discharged annually. Every ten cubic metre of liquid waste contains approximately one terabecquerel of Tc-99. Thus, BNFL may unwearied continue to empty its tanks, without being obstructed by the discharge permit allowing 90 TBq annually.
Furthermore, in the forthcoming year BNFL plans to discharge approximately 30 TBq of Tc-99 from the oldest reprocessing plant (B205).
According to figures Bellona have accessed, the discharges from Sellafield for the next four years may add up to as much as 300 TBq. At this pace, the tanks will be empty in 2006, the year the EA will restrict BNFL’s discharge permit to 10 TBq/year.
A reduction in discharges has been discussed
The possibility of implementing a chemical purification process as early as next year has been discussed – in part to meet the criticism from Ireland and Norway. There are however several elements of uncertainty associated with the technology preferred by BNFL.
First of all, this technology involves discharges of the precipitation agent tetraphenylphosphonium (TPP), which is a contaminant that even at very low concentrations is harming the environment. Secondly, it is uncertain whether the technology can clean out more than 75 percent of the discharges. And finally, as this represents an untried technology, it requires an approval from the British authorities.
In consequence of all this the Sellafield plant will until next year continue to discharge between 70 and 90 TBq of Tc-99.
The discharges can be stopped now
Investigations performed by the Bellona Foundation prove that by vitrifying both the existing waste and future waste arisings, the discharges of Tc-99 may be stopped with immediate effect.
The EA too recommends vitrification of future discharges of Tc-99 from the old reprocessing plant B205. The process of vitrification involves diverting the liquid waste into solid form, followed by storage in steel barrels for future deposition in mountain caves.
According to BNFL, a pipeline for transportation of Tc-99 to the vitrification plant does already exist. Despite this, British authorities allow more than 300 TBq of historic liquid waste to be discharged directly into the sea. The BNFL claims the reason for this is that the content of iron and sodium in the waste is too high, and hence make it inappropriate for vitrification. The level of iron and sodium can however easily be reduced by gradually mixing it with a different type of waste also intended vitrified.
The concentrations of iron and sodium would thereby be reduced to an acceptable level.
If the British authorities are to meet the commitments agreed on through the OSPAR and the North Sea conferences, in which British authorities themselves participated, the discharges of Tc-99 must cease instantaneously. If the discharges are allowed to continue, the Tc-99 concentrations in the environment in 2020 will necessarily exceed the current level.
The British Department for Environment, Food and Rural Affairs is currently reviewing the Tc-99 discharges from Sellafield.
Which type of purification technology BNFL will be instructed to install, is not yet decided.