North Area Carlin and Gold Quarry pits have haul road effective widths for two-way travel of 100 ft (30 m) for cut-to-fill roads and 120 ft (37 m) for external fill roads with a maximum grade of 10%. Minimum pit-bottom width is designed at 150 ft (45 m). Bench heights vary from 20 ft (6 m) to 40 ft (12 m). Crushing and Grinding.