Physical description

black and white image: shows semi-circular pit, brick walls held up with metal uprights and braces. Brickwork appears to be very old. Two men standing on LH side of image, at bottom of pit, wearing hard hats, overalls. Bottom of pit has concrete floor ( new ? ) on LH side. On back of image: 30 May 1975. Unabkle to read writing : Wr, Y,C, ?