Void

A large void inside the Ashio Copper Mine processing plant opens between two of the working levels, the floor of one level absent above the floor of the next. The void is rectangular in plan, framed by structural steel columns at the four corners and the floor edges around its perimeter. Cabling and pipework hang into the void from the level above, terminated where they once served a piece of plant that has since been removed. The floor of the lower level is concrete, stained where ore residue accumulated along the edges of the void. Daylight from the side windows two levels up falls into the void and reaches the lower floor as a soft rectangle of light.

Voids in a processing plant of this kind are typically the footprints of removed equipment: a large ball mill, a flotation cell, a smelter unit, a refinery vessel. When the plant was rationalised or rebuilt across the operational decades, the heavy machinery left behind these gaps in the structural floor. At Ashio the works was rebuilt and extended several times under the Furukawa modernisation from 1877 onwards. The Excavation Department closed in 1973, and the plant has stood as photographed since. The void in this image is the empty space left by a piece of plant that came out at some point in the working life.