HL Deb 09 May 1977 vol 383 cc151-3WA
Lord HYLTON

asked Her Majesty's Government:

  1. (i) What radioactive products have been discharged into the Irish Sea since 1964, and in what amounts;
  2. (ii) What studies of the effect of seacurrents on the dispersal of radioactive effluents have been made (a) before 1964, (b) since 1964;
  3. (iii) To what extent is radioactivity in the sea being monitored along the coasts of Scotland and England, North and South of Windscale;
  4. (iv) What is the present volume and degree of radioactivity of the materials reprocessed at Windscale, and by how much would these amounts be increased if the proposals made by British Nuclear Fuels Limited were to be approved in full; and
  5. (v) What requests have been made for new "Authorisations" for discharges in Cumbria of radioactive and toxic effluents into the sea and air.

Lord STRABOLGI

(i) The products discharged into the Irish Sea principally from Windscale are typical of the radio-nuclides found in irradiated fuel and comprise fission products such as strontium 90, ruthenium 106, cerium 144, caesium 137 and transuranics such as plutonium 239 and americium 241. Discharge data on a detailed basis is set out in the annual publicationRadio- activity in Surface and Coastal Waters of the British Isles published by the Radio-biological Laboratory of the Ministry of Agriculture, Fisheries and Food. Copies are available in the Printed Paper Office. Further additional data can be obtained from British Nuclear Fuels Limited (BNFL) who together with the United Kingdom Atomic Energy Authority have published reports on annual discharges from Windscale throughout the period.

(ii) Studies using dye tracers and drift monitors were carried out from 1946 onwards on dispersion characteristics of sea-currents to determine what would happen to discharges of radioactive effluents. Subsequently radioactive effluents have been used to monitor currents.

(iii) Monitoring is carried out by the operators themselves and the results for the Windscale area have been published by British Nuclear Fuels Limited together with the United Kingdom Atomic Energy Authority throughout this period. The Ministry of Agriculture undertakes monitoring to ensure that discharges are in accordance with the authorisations granted jointly by my right honourable friends the Minister of Agriculture, Fisheries and Food and the Secretary of State for the Environment. The results are published in the series Radioactivity in Surface and Coastal Waters of the British Isles.

(iv) I am advised that the material currently reprocessed at Windscale comprises up to 1,500 tonnes per annum of Magnox fuel and this will be unaffected by BNFL's current investment proposals for Magnox reprocessing. If BNFL's proposal for an oxide reprocessing plant is approved following the planning inquiry initiated by my right honourable friend the Secretary of State for the Environment, then, in addition, up to about 1,000 tonnes per annum of oxide fuel will be reprocessed.

Ths fission product activity of the Magnox fuel when reprocessed is about 100,000 curies per tonne and the total fission product activity of fuel reprocessed with the oxide plant in full operation would be on average about five times the present level.

I understand that BNFL has already given an assurance that despite this increase the greatest potential radiation dose for that small group of the public most significantly affected will be less than 10 per cent. of the dose limit recommended by the International Commission for Radiological Protection, i.e. substantially less than at present and much less for the public generally.

Any future discharges from Windscale would of course be subject to the authorisation procedure.

(v) As the 6th Report of the Royal Commission on Environmental Pollution says, a revised authorisation is in course of preparation by Departments to take account of detailed changes since the last one was granted.