<P> Mapping of the outcrop as well as core hole data and samples taken during the bench making process are taken into account to best project the panels that the Highwall miner will cut . Obstacles that could be potentially damaged by subsidence and the natural contour of the Highwall are taken into account, and a surveyor points the Highwall miner in a line (Theoretical Survey Plot - Line) mostly perpendicular to the Highwall . Parallel lines represent the drive cut into the mountain (up to 1,000 feet (300 m) deep), without heading or corrective steering actuation on a navigation Azimuth during mining results in missing a portion of the coal seam and is a potential danger of cutting in pillars from previous mined drives due to horizontal drift (Roll) of the Pushbeam - Cuttermodule string . Recently Highwall miners have penetrated more than 1050 feet into the coal seam, and today's models are capable of going farther, with the support of gyro navigation and not limited anymore by the amount of cable stored on the machine . The maximum depth would be determined by the stress of further penetration and associated specific - power draw, ("Torsion and Tension" in Screw - Transporters String) but today's optimized Screw - Transporters Conveying Embodiments (called: Pushbeams) with Visual Product Development and Flow Simulation Behaviour software "Discrete Element Modeling" (DEM) shows smart - drive extended penetrations are possible, evenso under steep inclined angles from horizontal to more than 30 degree downhole . In case of significant steep mining the new mining method phrase should be "Directional Mining", dry or wet, Dewatering is developed or Cutting & Dredging through Screw - Transporters are proactive in developing roadmap of the leading global Highwall mining company . </P> <P> In early stages of moving materials out of surface mines, manual labour, horse drawn vehicles and mining railways moved materials . </P> <P> Current practices tend to use haul trucks on haul roads designed into the features of the mine . </P> <Table> <Tr> <Td> </Td> <Td> This section needs expansion . You can help by adding to it . (November 2013) </Td> </Tr> </Table>

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