The high-grade mine, which is expected to produce 223,000 tonnes of copper a year, had been slated to start production in the fourth quarter, but Inmet said it can make no guarantees it will have the permit in place in time.
In that case, start-up of operations at the Las Cruces process plant and the resumption of mining activity in the pit, including the mining of ore for the process plan, would be delayed until the (water) authorization is reinstated, the Canadian company said in a statement.
Spain's water authority yanked the permit amid concern about contamination of the surrounding aquifer through wells on the property.
Inmet has since stopped mining near the ore body.
The company said it has developed a plan that could begin water purification on an interim basis by the end of August, while some of the wells are relocated.
Las Cruces contains proven and probable reserves of 17.6 million tonnes of ore at an average grade of 6.2 percent copper.
Inmet shares have fallen by about 25 percent since late April, as Inmet has also dealt with development delays at its Cerattepe project in Turkey.
(Reporting by Cameron French; editing by Rob Wilson)
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