OMG!  

"Under the reform, the total top tax rate will reach up to 46.5% for companies that produce over 80,000 tonnes of fine copper a year, considered a high tax rate by the industry.

 It also establishes a 1% ad valorem tax on copper sales from companies whose sales exceed 50,000 tonnes of fine copper, as well as an additional tax ranging from 8% to 26%, depending on the miner's operating margin."

So even if a mine scales back output to avoid the higher total top rate, they are then subject to additional taxes on good margins.

How can Teck possibly spend another single penny on capex in Chile?  Time for Teck to put an end to the self-inflicted financial catastrophy they are causing themselves by holding out for a better deal on our 25% of Schaft Creek.  Teck lost over $3 Billion US on a ForthHills investment sanction vs SC sanction and the many Billions in profit they would have had by now from Schaft Creek.  Teck sanctioned QB2 vs Schaft Creek and QB2's capex has cost them $8 Billion US so far, IIRC over budget by $4 Billion US more than originally claimed when scanctioned.   Losing over $7 Billion US as a result of holding out for a decade for just a couple of hundred million dollar discount on our 25%. Sounds like absolute madness, insanity, but it continues. Its just surreal.