45.2. Service roads used by motorized vehicles in an open-pit mine shall:(1) be edged by a pile of fill or a ridge where vehicles could fall more than 3 m (9.8 ft). The pile of fill or the ridge shall have a height equal to at least the radius of the largest wheel of any vehicle travelling on the road;
(2) be off-limits to any vehicle whose width exceeds that of the driving surface;
(3) be maintained by clearing or scarifying or by spreading an abrasive substance, so as to keep a non-skid surface.