Today beneath Towneley Park along with clay and sandstone are large amounts of water and a small amount of coal. When Burnley Corporation purchased Towneley Hall in November 1901, they also purchased the mineral rights directly beneath as otherwise the coal would have been taken and the Hall would have fallen down. Coal was taken from beneath the rest of the Park and subsidence occurred there throughout the first half of the 20th Century.
Above (part of doma3529) is a section plan of the coal beneath Towneley Hall, signed Wm. Eagle and dated 5th July 1897. The coal seams near the surface such as the Thin Mine and the King Mine had worked since early in the 19th century but had not undermined the Hall. The lowest seam, the Arley Mine, was the most valuable and had been mined at Towneley Pit since 1876. The album shows plans for all the coal seams. The plan of the Arley Mine shows the Hall is still being supported today by pillars of coal left after the rest of the coal below Towneley Park was worked out.
No coal was taken from Towneley Pit after 1948 but it continued as a pumping pit removing water for another twenty years to safeguard the deeper workings of other pits in the area. It is remarkable that during its lifetime, Towneley Pit probably brought up 5 tons of water for every ton of coal.