With new articulated truck on site, Goldsource hits planned throughput

VANCOUVER (miningweekly.com) – With a brand new 40 t articulated truck arriving in Guyana after clearing customs on Thursday, Canadian gold miner Goldsource Mines was confident that it would once more hit planned throughput rates at its flagship Eagle Mountain mine and mill over the weekend, the company said on Friday.

While Goldsource is transitioning from the lower-grade (0.3 g/t to 0.5 g/t gold) commissioning pit to the higher-grade (1.4 g/t gold) Pit #4, the delay in the delivery of the 40 t articulated truck – which is required to haul ore over the 240 m distance between the pit and the mill – forced the company to suspend production and cut 2016 guidance in half.

“From this weekend, mining and milling will continue at normal speed,” Goldsource president and director Ioannis Tsitos told Mining Weekly Online in a telephone interview on Friday.

He explained that, as is common during the commissioning phase of many mining projects, the Eagle Mountain team have been dealing with teething problems since declaring commercial production at Eagle Mountain in June, fine-tuning the plant and pumps.

“In our case, we have built the mine on a shoestring budget, using a phased approach. Should something go wrong, it often has a bigger impact and can take longer to resolve,” Tsitos advised.

The extremely heavy Monsoon rains, owing to La Nina, at Eagle Mountain, also compounded matters, slowing equipment movements at site while, to a lesser extent, resulting in excess water in the mine workings.

Eagle Mountain’s first phase had previously reached consistent production averaging a minimum of 80% of the 1 000 t/d nameplate capacity and 45% recovery in gold concentrate.

However, Goldsource last week said processing operations were suspended on July 23 to reduce consumable costs, while focusing on developing access to Pit #4 and preparing Pit #4 for openpit mining. The company has reduced its 2016 production guidance to between 1 400 oz and 2 100 oz of gold, down from the previous guidance of 3 600 oz.

Tsitos noted that the Eagle Mountain mill was restarted eight days ago to start processing the more than 6 000 t of stockpiled high-grade material from Pit #4 at a modest throughput rate, using a 15 t truck that was pressed into service in the interim.

“With the 40 t truck on site, a throughput of 1 250 t/d to 1 500 t/d from Pit #4 to the processing plant should be achieved,” Tsitos stated.

Management expects to implement a second night shift this month, increasing the operation from 15 hours a day to 20 hours a day.

Further, Tsitos explained that, despite management having applied for a permit from the Guyana government to operate a low-impact intensive cyanide leaching circuit (SLR unit) at Eagle Mountain, which is expected to substantially improve gold recovery and production from the mine, the permit that was expected in July has not yet been issued and there is no firm date for its issuance.

“The delay in getting the permit will not impact the current mine plan. It is not critical and we can move on unhindered,” Tsitos said.

Meanwhile, the board has authorised management to start looking at securing Phase 2 capital. On successful completion of Phase 1, three similar plants will be sequentially installed to increase production to between 3 500 t/d and 4 000 t/d by Year 4.

The company will also look at adding a second modified scrubber to the Phase II plant, doubling the current falcon concentrators from two to four units and implementing the Phase II expansion for less than the $18.3-million total capital budget outlined in the August 2014 preliminary economic assessment.

Goldsource plans to start work on a prefeasibility study during the fourth quarter, which will entail more drilling to improve confidence in the project’s resource models.