Coal Industry Archives ASGCO | ASGCO
Roomandpillar mining. In roomandpillar mining, coal deposits are mined by cutting a network of ''rooms'' into the coal seam and leaving behind ''pillars'' of coal to support the roof of the mine. These pillars can be up to 40% of the total coal in the seam – although this coal can sometimes be recovered at a later stage. Longwall mining