{"data":{"id":"us-va/4vac25-101-170","jurisdiction":"us-va","citation":"4VAC25-101-170","heading":"Pillars of coal to be left unmined, and other protective measures","body":"A. When mining using an underground, auger or highwall mining method within 200 horizontal feet of a vertical ventilation hole or a gas well, the mine operator shall submit a plan showing the projected pillars of coal to be left unmined around each hole or well.\n\nB. Pillars shall be situated so that each hole or well is centered within a pillar, and each pillar shall conform to the specifications shown in Table I below, based on the depth of cover above the area being mined. The entries developed adjacent to any pillar may not exceed 20 feet in width without prior approval from the chief. In no circumstances may the most narrow pillar dimension be less than twice the width of the adjacent entries.\n\nTable I\n\nPillar Specifications\n\nCover (in feet)\n\nRequired Solid Pillar Area (in square feet)\n\nRequired Additional Pillar Area (Solid or Split, in sq. ft.)\n\nTotal Area Bearing Surface Required (in sq. ft.)\n\n0-149\n\n3,600\n\n3,600\n\n150-249\n\n5,625\n\n5,625\n\n250-349\n\n10,000\n\n10,000\n\n350-449\n\n10,000\n\n5,600\n\n15,600\n\n450-549\n\n10,000\n\n13,000\n\n23,000\n\n550-649\n\n10,000\n\n22,000\n\n32,000\n\n650 or more\n\n10,000\n\n30,000\n\n40,000","path":["Title 4. Conservation And Natural Resources","Agency 25. Department of Energy","Chapter 101. Regulations Governing Vertical Ventilation Holes and Mining Near Gas and Oil Wells"],"source_url":"https://law.lis.virginia.gov/admincode/title4/agency25/chapter101/section170/","current_through":"2026 Regular Session (effective July 1, 2026)","vintage":"","retrieved_at":"2026-09-14T04:46:12Z","sha256":"008e1cdfecb41c688cd74cfa14da94964e9e403c928054a8e4bf67ae7fd37a11","source_id":"us-va-vac","stale":false,"prev":"us-va/4vac25-101-160","next":"us-va/4vac25-101-180"},"notice":"GroundRules: Original legal text. Not legal advice."}