Round Mountain’s commitment to Continuous Improvement is evident in every aspect of their day-to-day work.
A great example of this is when the team came together in 2014 to find a way to leach Gold Hill ore in a more efficient way to save on costs and increase production.
“We originally made the assumption that the clay in the Gold Hill ore would be similar to Round Mountain ore,” said Frank Wagener, Continuous Improvement Manager, Round Mountain. “But, this turned out to not be the case and created a situation where we had leach pads that would not allow the solution to go through quickly. We were getting ounces, but it was taking too long to get them – a year or longer to get 50% of the gold.”
Facing the challenge of finding a new way of speeding up gold recovery from the leach pads, Round Mountain went back to the drawing board.
Leveraging a multi-disciplinary team – which included the Metallurgical, Geology and Mine Planning departments – Round Mountain was able to develop a new heap leaching model to enhance recovery by analyzing blending strategies, cut-off grades, leaching and revising recovery options.
“In the lab, we proved that blending ore enhanced recovery, so we thought: could we make it happen in the field at Gold Hill?” continued Frank.
Three test pads were used to assess different blends to get to the two blending strategies that they use today: blend soft advanced argillic clay ore at a 1:1 ratio with harder run-of-mine clay ore and blend the very soft extreme argillic clay ore at a 1:1 ratio with run-of-mine rock ore. The blending occurs as it is stacked onto the leach pads.
Round Mountain tested the new model at Gold Hill and right away more ounces were being recovered as the solution was able to saturate the ore more quickly. The new method is proving to be a success as it helped Round Mountain achieve a net increase of 91 Au koz. on a 100% basis in 2015 compared with 2014.
“Getting the best blend takes extra effort to get it right, but has been well worth the time. This is the result of many departments working together to make it possible,” said Frank.
Loading ore at Gold Hill
At Gold Hill
