Dr. ThomasTo ask the Secretary of State for the Environment what quantities of radioactive barium sulphate residues remain at Amersham International sites; what is their total curie content; and what present plans exist for the final disposal of these radioactive wastes.
§ Mrs. Virginia BottomleyA total of 1.5 gigabequerels (approximately 40 millicuries) of radioactive barium sulphate residues remain at the Amersham International site at Amersham. No such residues are stored on any other Amersham International site.
The residues are sludges contaminated with radium-226 resulting from the treatment of radioactive effluent prior to discharge from the site. Residues are stored safely in the site effluent treatment plant. When the plant is de-commissioned, the waste sludges will be disposed of safely under the terms of an authorisation issued by HMIP.
Some radioactive barium sulphate residues arising from work on radium-226 in the 1940s and 1950s were at that time buried on the Amersham site. These burials were excavated in the late 1960s and the radioactive waste was disposed of by burial at the British Nuclear Fuels disposal site at Drigg in Cumbria.