§ Mr. Frank Cook
asked the Secretary of State for Energy (1) how many control rod sections in how many control rods will need to be replaced or refurbished at Heysharn and Torness advanced gas-cooled reactors, following the discovery of (a) external damage, (b) internal damage to bearing surfaces and (c) faulty workmanship; and what is the estimated cost;
(2) whether destructive tests have been performed, and whether any are proposed, on articulated joint bearings of control rods at the advanced gas-cooled reactor stations at Hinkley Point and Hunterston, in order to confirm that they do not suffer wear of the kind discovered at Torness and Heysham;
(3) what steps have been taken to discover whether wear has occurred in the control rod joint at the advanced gas-cooled reactor stations at Hinkley and Hunterston;
(4) what evidence was available to the Central Electricity Generating Board that potential instability in control rods due to gas flows existed in the advanced gas-cooled reactor design at Hunterston and Hinkley, before construction of similar designs began at Heysham and Torness;
(5) what is the cost and estimated delay as a result of the design failures of the control rod assemblies at Torness and Heysham; and if a proven design has yet been found;
(6) if any steps were taken to rig-test control rod assemblies at Heysham and Torness advanced gas-cooled reactors after minor redesign of the gas inlet nozzles from the original Hunterston/Hinkley design; and if he will make a statement;
(7) on how many previous occasions control rods have failed to insert fully on demand into the reactors at Hunterston and Hinkley advanced gas-cooled reactors; and for what reasons.
§ Mr. Goodlad
I have asked the chairman of the Central Electricity Generating Board to write to the hon. Member on behalf of both South of Scotland Electricity Board and CEGB.