This is not about a defective boiler pump.. It's about a reoccurring problem with broken boiler re-enforcing wires
They found a broken boiler spine in 2007, and spent 150 million pounds investigating fixes.. from what I've read they found more corroded/broken per-stressed re-enforcing spines.
excerpt from report dated Sept 2010,
"3.4. Leaking pressure vessel cooling water was also found to have entered a chamber containing BCU pre-stressing wires and as a consequence of this, a programme of radiography to reveal corrosion degradation was initiated. During inspections on Reactor 1 at Hartlepool in late 2007, the tendon wires were found to have unexpectedly high levels of corrosion, which led to one tendon wire having broken near to its anchor. Subsequent inspection of the BCUs on these other reactors found similar evidence of corrosion, indicating that this was a generic issue, not confined to Reactor 1 at Hartlepool."