Donuel there are still plague pits in London where the bones carry the bacteria for bubonic plague.
A poem by Thomas Hardy on their disturbance during railway building.
He worked as an overseer for the Clerk of Works, and inspired by the scene memorably began: “We late-lamented, resting here, Are mixed to human jam, And each to each exclaims in fear, ‘I know not which I am!’”

Great attention is also paid to old leather works because of the fear of potential anthrax. The cross rail scheme in London encountered both.

http://www.bbc.com/autos/story/20160906-plague-pits-the-london-underground-and-crossrail