A planning application for extending mining at Gleision Colliery reveals more details of the mine.
In January 2009, the mine’s operators put in a bid to extend mining at the colliery through Neath Port Talbot County Borough Council. This included several supporting maps to show the geology, water, and surface area around the mine.
The document confirms the mine, as it now operates, has been in operation since 1993. Mining is for anthracite coal in the No. 2 Rhondda Seam.
The operation of the mine is described, as well, detailing a 7am start and 7:30pm finish on weekdays. Maintenance was reserved for Saturdays from 7am to 1pm. Sundays and bank holidays the mine closed.
For all the details, the document can be read in full below: