The Canadian lake based mining industry has strengthened its position in the global market in recent years with the establishment of several new large mining operations that have led to Canada becoming the world’s largest producer of zinc and uranium.

Several of the world’s leading mining companies operate diamond mines in Canada, including: De Beers’ Snap Lake mine, Rio Tinto’s Diavik mine and BHP Billiton’s Ekati mine.

A South African based firm of marine engineers, Marine and Mineral Projects (MMP), is investigating the possibility of adapting their existing underwater crawler technology, currently being used for marine diamond mining by De Beers off Southern Africa, for lake based applications in Canada.

According to Rodney Norman, the Managing Director of MMP, the idea is very much in the early stages and the company still need to do further investigation, to consider aspects such as the environment, geology, climate, location of each mine etc.

“As we understand it, the mining of lake-based deposits involves the construction of massive concrete and stone dikes around the site. The area of lake within the dikes is then pumped dry to allow access to the lakebed.”

“We believe that it may be feasible to adapt our current marine diamond mining technology to mine the bottom of a lake without having to drain the water. This would mean that the mines would no longer have to build these huge dikes at vast expense or disrupt a lake’s ecosystem to reach the deposits.”

An example of this is the Diavik diamond mine in Lac de Gras. Here the dikes average ten metres high but can get as high as 28 metres. In other instances, entire lakes are drained to access the mineral rich deposits hidden beneath their depths. An example of this is Steep Rock Lake in North Western Ontario, which required the dewatering of the lake with a surface area of over five square miles, the diversion of a major river system, the lowering of nearby Finlayson Lake by 40 feet and the largest dredging project ever to be undertaken in Canada.

At the BHP Billiton diamond mine, Ekati, a string of lakes have been drained for shovel and truck, open-pit mining to take place in the exposed Kimberlite bodies.

“Understandably,” says Norman, “the process of building these huge dikes and/or draining the lake is vastly expensive and time consuming, plus this method of mining has a fairly large environmental impact on the area while the mine is in operation, with additional expense to rehabilitate an area once mining activities have ceased.”

“Our current marine technology consists of a 250 tonne remotely operated underwater crawler that is equipped to cut into the ocean bed and then vacuum up the diamondiferous material which is pumped to the ship based treatment plant through a 650 mm internal diameter rubber hose using a 2.4MW dredge pump system. A 500KW hydraulic power pack powers the systems on the crawler.”

“A pilot and a co-pilot operate the crawler through a system of twelve computer monitors that provide readings on production, oil and water levels, pressures, temperatures etc. In addition the pilots see a virtual animation of the movements of the crawler, the seabed and the mining process.”

According to Norman, one crawler unit is capable of extracting approximately 400 tonnes per hour or approximately two and a half million tonnes of product a year.

“We asked ourselves that if it is possible to mine the bottom of the ocean with this technology then why not the bottom of a lake? Any lake based deposits can potentially be mined using our crawler technology, so this adaptation possibly applies to uranium, zinc, gold, copper, nickel and so on.”

“Marine And Mineral Projects believes that this idea is feasible and are excited at the prospect as it has the potential to greatly assist and enhance the industry,” concludes Norman.

Visit http://www.marineandmineral.com/ for more information about Marine and Mineral Projects.
View explanatory graphics and photographs of the deep sea crawler technology on: http://www.marineandmineral.com/solutions/.