Bowmans Harbour opencast mine is probably unique. Here Clay Colliery is mining an area that was derelict and contaminated land, which became a landfill site. When standards for landfill were raised the Black Country Development Corporation decided to redeposit the waste in a new repository on the same site, using higher standards. New cells for waste are being constructed. In creating these new cells coal is being extracted and sold. Four excavators are involved in this project.