Canadian firm eyes Cuyuni for large scale mining, hydropower plant

Guyana Goldfields Incorpo-rated has applied to the Environmental Protection Agency (EPA) for permission to open a large-scale mine at Aurora, Cuyuni River, which if approved could see the construction of a hydropower facility across a section of the river.

The proposed project will entail the operation of both open pit and underground mines, mineral processing to recover gold, the construction of a hydroelectric plant to provide power to the processing plant and the construction of an access road and wharf to service the operation.

Guyana Goldfields Inc is a Canada-based mineral exploration company primarily focused on the exploration and development of gold deposits in Guyana, where it has operated since 1996.

An EPA notice in yesterday’s edition of the Guyana Chronicle said that in accordance with the Environmental Protection Act, an Environmental Impact Assessment (EIA) is required for Guyana Goldfields Inc before any decision to approve or reject the proposed project is taken, since the development may have significant impacts on the environment. The EPA invited members of the public to make written submissions to the agency within 28 days of the notice being published, setting out questions and matters which they require to be answered or considered in the EIA.

According to the project summary, the development and operation of the mine site will involve construction and operation of the mine site, construction and operation of a hydropower plant on the Cuyuni River, construction of an access road to the mine site, and construction and operation of a wharf at Buck Hall on the Essequibo River.

Ore recovery will consist of a combination of open pit and underground mining and the combined schedule will result in a mine life of approximately 12 years. Power for the process plant operation and ancillary services, according to the summary, will be provided by a run-of-the-river pondage hydropower plant to be constructed on the Cuyuni River, 8km away from the mine site. According to the Guyana Goldfield’s website, a 10-15 megawatt hydroelectric facility is envisioned and two prefeasibility studies done found that the optimum site both technically and economically is the Julian Ross Itabu River location, where the installed capacity is calculated to be 11MW.

The project summary said that a road will be constructed from the mine site to access the power plant location and the hydropower facility will entail construction of a dam across Julian Ross Itabu. The proposed facility will be located in the left branch of the Cuyuni, 8km upstream of the proposed mine site, in an area where the Cuyuni River divides into Devil’s Hole and Julian Ross Itabu on the left and right respectively. It will be located on the Julian Ross Itabu branch of the river, which is the smaller of the two branches that join downstream to form the Cuyuni River and which carries 35% of the total flow of the Cuyuni River at this point. The facility will consist of an earth-fill dam, a spill way, bottom outlets for the reservoir and the power station.

Meanwhile, three mineralized zones, namely Aleck Hill, East Walcott and Rory’s Knoll, have been identified at the site and the mineral recovery operations will consist of a combination open pit and underground mine operation followed by a tank contained cyanide leaching plant for gold recovery. The plant is expected to process 3.5 million tonnes of ore per year. It was noted that historic surface water levels in the Cuyuni River will result in encroachment of water from the waterway into the open pit at Rory’s Knoll and a flood mitigation barrier will be constructed between the pit and the river at this point.

The mineral processing circuit in the plant will treat 1,000 metric tonnes per day of ore by gravity separation and cyanide vat leaching. The tailings pond will be lined with a homogeneous, tamped benontite/laterite underlay, plus a 20-mil PVC top liner and the environmental section will consist of a series of ponds where excess effluent from the final tailings pond will be treated.

The wharf, the project summary said, will be located on the Essequibo River at Buck Hall and will be designed to handle general cargo. According to the company’s website “with 2,000 feet of deep water frontage the proposed port will be able to accommodate all sea going vessels and provide easy access for shipments to or from Miami, Houston, and other International ports.” The company has already built a 2,000-feet airstrip at the location.