A letter just sent from a supporter of Radiation Free Lakeland to EDF the operators of Hunterston B. The Reactors at Hunterston have now been running for over 43 years. The graphite cores have multiple cracks with debris in the control rod holes and the control rods have had to be fitted with gimbals so they are able to snake down the holes in the distorted under moderated core. Hunterston, like Hinkley Point B and Dungeness, does not have the tertiary last-ditch boron ball system fitted to subsequent AGR’s. The Cooling Gas Circulators have been found to be running beyond their design life at Hunterston, like the ones at Hinkley Point B.(As noted in the Q3 site reported detailed below) The Pre-stressed Concrete Pressure Vessels in all of your AGR’s are suffering from corrosion of the tendons such that many like the one at Hartlepool leak cooling CO2 from within their nuclear cores. Have a read from page 8 of this document form the ONR for as far as you can stomach it (http://www.onr.org.uk/operational/tech_asst_guides/ns-tast-gd-020.pdf) Especially these lines – “The Heysham 2, Torness and Hunterston B PCPVs have all been affected at various times by minor blockages of parts of the PVCS [Pressure Vessel Cooling System] with the potential for increased concrete and penetration temperatures. Blockages have been caused by small-sized debris in the system becoming trapped at the throttled back flow control valves. The potential exists for coincident blockage of both the 100% duty dual A and B circuits leading to elevated concrete temperatures and unacceptable thermal gradients. 5.34 There is the potential for loss of PCPV penetration restraint with subsequent penetration ejection or of failure due to elevated temperature of the penetrations and surrounding concrete known to be ‘non-tolerant’ to elevated temperature.” Nuclear sites across the UK have jerry-rigged restraints built around their CO2 cooling gas circulators to prevent them from popping out, like champagne corks, of their 600PSI CO2 filled nuclear cores !!
Radiation Free Lakeland 11th Dec 2019 read more »