Hi there Cliff,
I have quite a bit of experience with Lead Sheathed cables.
Back when I started my time as an apprentice Liney here in New Zealand we were taking out this sort of cable (mainly singles) used to feed the odd commercial building.
To be honest, lead is something that everyone is against because of it's effect on the environment.
Sure, the cable might be OK, but at the end of the day, it really does need to be replaced with something "safer".
The actual cable itself uses a jute weave insulation upon a copper inner conductor, hence, if it gets wet at all, you can expect either a fault to earth which will often blow out a large section of the lead insulation and damage the jute insulation.
The reason we started replacing these cables was because of the clamps used to earth the outer sheath, would work loose over time, in so much that they became a safety risk with fuses not clearing when they should have done.
Lead is a very soft metal and very hard to keep a really good clamping force on, without deforming the sheath (which also reduces the insulation resistance at that point).
Mate, IMO, either XLPE or PVC sheathed cables HAVE to be better than Lead sheathed cables.
In a place where it was not possible to replace the Lead cables, I was sent to joint one, one night.
All I can say is it was a real nuisance, it took 4 and a half hours to joint a cable that should have taken an hour at the most.
Cliff,
Times change, as far as I can see $675K would be a small price to pay for peace of mind.
I never want to see another lead sheathed cable again, they've had their day, let's move on.
