auger mining evolved

  • A Review of Highwall Mining Experience and Practice

    contour mining, as a type of auger system. The first auger system excavated a single hole of 1.5 m in diameter and 30 m long, and recovered 726 tonnes of coal per day with a four-man crew. While the auger mining system was regarded as a new productive mining method, some problems encountered with the increased penetration depth of up to 120 m.