Correspondence file on management of Bolsover Colliery File of Secretary's Department Deputy Director (Administration) Central Area/. Including minutes of meetings, reports and corresondence on development of Blackshale Seam, copies of Health and Safety Executive letters on compliance with regulations, letter on question of union recognition, 6 Sep 1988, and loose minutes of quarterly colliery accountability meeting, 31 Jan 1989 Apr 1987-Dec 1988