Peter Masson wrote:
The Sunday Times article is ambiguous - I think the 7000 is meant to refer
to the original construcion of the Midland Railway, but it could be read to
refer to the CTRL.

It must refer to building the Midland route and the Metropolitan (now
Thameslink) connection. If 7,000 bodies had been exhumed during the
CTRL work then we'd have heard about it beforehand. The Guardian G2
article on Friday (27/05/05) has no such mention of this.

It sounds like the CTRL lecturer the OP spoke to is correct - a 'few'
bodies were exhumed. 7,000 is not a 'few'!

When on Thameslink it's certainly an odd to think that you're
travelling through a burial ground.