City: Crested Butte
Harrison Western remediated the Standard Mine in several phases. Phase I included rehabilitation of a portal and adit in order to establish safe entrance to the mine to determine the best locations to construct bulkheads to control discharging contaminated water. In Phase II, HW safeguarded two levels (1 and 3) for future work. On Level 1, a new adit was driven 500 feet parallel to the original mine workings in order to safely access collapsed areas. A concrete bulkhead, HDPE discharge piping, and a weir were installed in the original adit. On Level 3, additional safeguarding measures included filling raises with foam, filling winzes with concrete, spot bolting, and installing steel and timber cribbing. HW directed the water out of the discharge line from the bulkhead, through the adit and portal, and into a series of passive wetland treatment ponds.