Mining News: Poor recoveries slow Hope Bay Mine start

TMAC Resources Inc. July 14 reported that ramp up to full operation at its Hope Bay gold mine in Nunavut is slower than expected, resulting in less cash-flow than the company had budgeted. “Our entire site-based team’s focus – assisted by our metallurgical consultants and Gekko, the manufacturer of the processing plant, and other vendor and consultant teams – is to improve plant availabilities and ramp up to planned rates through an optimization process,” said TMAC CEO Catharine Farrow. While the underground development at Doris North and Doris North BTD continues as planned, the daily mining rate at Doris North remains less than planned due to the reduced tonnage being fed into the processing plant. At the end of June, 79,600 metric tons of ore have been processed and 15,880 ounces of gold have been sold. In addition, surface 105,000 metric tons of ore averaging 15.2 grams per metric ton (51,000 oz) gold is stockpiled on surface; and multiple underground stopes are ready for mining. The processing plant can and has operated at or in excess of its design capacity of 1,000 per day, but its average daily throughput continues to be lower because of variable and sometimes low plant availabilities. To improve throughput, modifications are focused on optimizing the pre-concentrator, known as the python, installed in the upstream half of the processing plant. The concentrate treatment plant, situate downstream half of the python, continues to have lower than expected throughput availabilities and recoveries due to a variety of challenges including design issues and mechanical failure. The CTP recoveries of the gold in the concentrate from the Python averaged 67 percent in June, much less than anticipated. The inconsistent availability and recoveries of the CTP have negatively affected the tonnage of ore being fed to the processing plant and mined daily. With low recoveries, TMAC continues to feed lower grade ore to the plant, resulting in lower gold produced and revenues.

Separately, TMAC reported 14.53 million metric tons of proven and probable reserves at Hope Bay averaging 7.7 g/t (3.61 million oz) gold, a 2.9 percent increase from the 3.51 million oz included in the 2015 pre-feasibility study for the gold project.

–SHANE LASLEY