Peruvian regulator returns preliminary review of Tambogrande

The Instituto Nacional de Recursos Naturales (Inrena), the Peruvian government agency charged with advising the government on new mining projects, has completed its preliminary review of the environmental-impact assessment submitted by Manhattan Minerals (MAN-T) for the Tambogrande polymetallic project in the Piura department of northern Peru.

Inrena has raised concerns about the tailings disposal area and about the desirability of displacing fruit-growing areas in order to mine Tambogrande. Manhattan is proposing a 7,500-tonne-per-day open-pit mine and mill complex for the TG-1 deposit, which has reserves of 8.2 million tonnes grading 3.3 grams gold and 58.7 grams silver per tonne.

Subsequent plant expansion would permit production of copper and zinc from the sulphide zone of the TG-1 deposit at a rate of 20,000 tonnes per day. Reserves in that zone of TG-1 amount to 57.8 million tonnes grading 1.5% copper, 0.9% zinc, 0.5 gram gold and 25 grams silver per tonne.

Inrena’s role is to provide a preliminary review to the country’s Ministry of Energy and Mines. The current review, some of whose contents were leaked to the Reuters news agency in Lima by a government source, is said to have raised 114 “observations” on the impact assessment.

In the process that follows the Inrena review, the Ministry of Energy and Mines holds public consultations and performs its own technical review of the impact assessment. Manhattan, in a release prompted by the Reuters report, noted that mining projects that had been approved had drawn similar numbers of observations from their preliminary Inrena reviews.