Re: The secrecy
I worked for a few weeks at Windscale in the late '70s, we were fitting the earth bars to the rows and rows of 3 phase cabs that controlled all the switching on a new pond.
The security was highest around our copper earth bars, they were about 1cmX 5cmX 50cm and at 2 kilos a piece, were worth a small fortune at the scrappy!
The money was good and the site canteen was out of this world, pint mugs of tea and good cooking, the only thing I was less keen on was the fish and chips, I can't seem to eat a fish with three eyes.