VANCOUVER (miningweekly.com) – Base metals-focused miner Taseko Mines has decided to proceed with the $25-million construction of a production test facility at its Florence in situ copper project, in Arizona, after winning a third-party appeal against the federal underground injection control (UIC) permit that was issued late last year.

The TSX- and NYSE America-listed company on Friday reported that the Environmental Appeals Board (EAB) of the Environmental Protection Agency had issued an order denying any further review of the UIC permit. The EAB found that the petitioners failed to demonstrate that any errors were made in issuing the federal permit.

“We are very pleased with the EAB decision, which is another significant milestone for our Florence copper project. We now have all necessary state and federal permits in place to build and operate the PTF,” commented president and CEO Russell Hallbauer.

Over the past year, Florence personnel have been advancing on-the-ground activities and have spent roughly $4-million specific to the PTF. With significant components already on site, the timeline to having the test facility operational is in the latter half of 2018 and involves the construction of a solvent extraction-electrowinning facility and the drilling of observation, injection and recovery wells.

“At $4 700/t of installed capacity, Florence Copper is one of the lowest capital intensity copper projects in the world. The economics of the project are too compelling for us to not be rapidly advancing the project towards commercial production, especially as a significant global copper deficit approaches.

“Successful operation of the PTF will be a major step towards realising the $920-million net present value (NPV) of the project. As we continue to move towards commercial production, we fully expect this value to be reflected in our share price,” Hallbauer added.

Taseko had in January released updated project metrics, calculating a pre-tax NPV, at a 7.5% discount rate, of $920-million, and an internal rate of return of 44%, with a 2.3 year capital payback.

The optimised mine plan was based on a long-term copper price of $3/lb, with operating costs estimated at about $1.10/lb of London Metals Exchange-grade cathode copper.

Florence is slated to produce on average 81-million pounds of copper a year, over a 21-year operating life. Total output is forecast in excess of 1.7-billion pounds of red metal, with total pre-production capital cost of $200-million.