From Google Earth I estimate the tailings pond to be 15 hectares in size or 150,000 sqare meters.  One meter of mine waste will weigh about  370,000 tons so if the QR mill is to process the 600,000 tons from Bonanza ledge and the Smithers mine it will fill in the tailings pond about 1.8 meters deep.  I wonder how much they added to the dyke?  They obviously won't be using this much in the future unless they drain it and move the sediment somewhere else.