Pleasley Colliery from the south  1904 - 1919 (FoPP)

1900s

• New headstocks installed at both pits.
• South pit upgraded to full coal winding.
• South screens renewed.
• North winder replaced.
• North pit cages upgraded.

1910s

• Larger ventilation fans installed.
• Large capacity water softener installed.
• Turbine DC generators installed.
• South pit deepening work started.

1920s

• South pit deepening and ventilation drift completed.
• South winding and decking arrangements upgraded.
• Steam generation plant reconstruction completed. 
• Deep Hard pit bottom construction completed.
• Roadway drivage to ventilation drift completed.
• Roadway drivage and face headings completed.
• Deep Hard production commences.
• Large turbine AC generator installed.
• Main ventilation fan electrified
• New North screens with washery plant constructed
• New South screens constructed
• Deep Hard production suspended.

1930s

• Spoil-heap aerial-ropeway constructed on north side of the Midland Railway cutting.
• Development of Dunsil  seam commences
• Simon-Carves Baum washer plant constructed to SW of pit-top.
• Railway shunting and weighbridge arrangement reconfigured

1940s

• Production now under way in Dunsil seam.
• Development of 1st Waterloo seam commences
• Top Hard production faces now more than 2 miles from pit bottom.