According to their last Investor Presentation in May 2017 CFE...

According to their last Investor Presentation in May 2017 CFE currently has 70% interest in the dam and will increase to 85% and the Kipushi tailings dam was over 1km in length, 400m in width and average 8m deep. So according to my calculations that makes it 1,000 X 400 X 8 = 3,200,000 cubic metres

3,200,000 X 10-12% Copper X 95.8% recovery = 306,560 to 367,872 cubic metres of Copper.
According to Google one cubic meter of copper apparently = 8,930 kg's
306,560 X 8930 = 2,737,580,800 kgs or 2,737,581 tonnes
1 UK Ton = 2,240 pounds. Copper currently approx. $3.02 per pound.
2,737,581 X 2,240 X $3.02 = 18.5b USD in ground value.

3,200,000 X 1.8-2% Cobalt X 83.5% recovery = 48,096 to 53,440 cubic metres of Cobalt
According to Google one cubic meter of cobalt is apparently = 8, 900 kg's
53,440 X 8,900 = 475,616,000 kg's or 475,616 tonnes
1 UK Ton = 2,240 pounds. Copper currently approx. $43.09 per pound.
475,616 X 2,240 X $43.09 = $45.9b USD in ground value.

Please feel free to let me know if I've royally screwed something up as these figures look way too high to me.