Increased Strip Ratio at Tenke FungurumeSpacegimp,
You're quite right that multiple long narrow open pits with a strip ratio of 3.3 will increase total waste. For a low grade copper porphyry a strip ratio below 3 is considered good. At TF we're looking at high grade 5.3% copper equivalent. For example, Lundin's Candelaria Mine in Chile has a strip ratio of 2.8 with an average grade LOM of 0.57%. I'd much rather have 5.3% copper equivalent with a strip ratio of 3.3, than 0.57% Cu with a strip ratio of 2.8. It's in this light that Lundin's decision to abandon TF must be viewed. The additional cost of extra waste is negligible compared to the potential profit.
Make no mistake, in some another country, Tenke Fungurume would be a license to print money.
A good comparison for TF is Nevsun's high grade Bisha mine in Eritrea, copper-zinc with gold and silver credits. The overall grade there in terms of copper equivalence is similar to TF and they have a strip ratio of 5.4.