NAP reduces output as crusher breaks down

A shutdown of the primary crusher has forced North American Palladium (PDL-T) to curtail production at its Lac des les mine in northwestern Ontario.

During the three months ended Sept. 30, the mill processed more than 1.2 million tonnes to produce 51,168 oz. of palladium — 18% less than in the previous quarter. Byproduct production also was down, at 4,753 oz. platinum, 4,137 oz. gold, 655 tonnes copper and 298 tonnes nickel.

The shortfall reflects the emergence of two vertical fractures in the bottom shell of the primary crusher. Since their discovery, in early September, the company has been using an old primary crusher.

Recovery rates averaged 72% in the recent period, or 4% less than in the previous one.

NAP also suspended mining activities for the remainder of the period, to control operating costs. A low-grade stockpile was tapped instead, and the average head grade for the period came to 1.83 grams palladium per tonne — 9% less than in the second quarter.

Repairs to the damaged crusher are expected to take several weeks to complete. In the meantime, throughput rates have recovered to about 14,000 tonnes per day, which is comparable to the mill’s performance in the second quarter but still 1,000 tonnes shy of capacity.

On a brighter note, the Toronto-based company has completed pilot-plant tests on the use of finer crushing sizes. Higher palladium recoveries were achieved, and large-scale tests using the plant’s two existing tower mills are scheduled to begin in November.

North American has had to tinker with the new mill since firing it up in mid-2001. Among other things, it has replaced the original pebble crusher with a larger one and installed a secondary crushing circuit; however, the design rate of 15,000 tonnes per day was only achieved in August, before the latest problems arose.

Lakefield Research managed the pilot tests.

At last count, reserves at Lac des Iles stood at 93.5 million tonnes grading 1.53 grams palladium, plus platinum, gold, copper and nickel. The estimate is based on a cutoff grade of 0.7 gram palladium per tonne and a palladium price of US$400 per oz.

North American Palladium has filed a business interruption claim with its insurers.