Studies continue at Puffy Lake

A recent study by Kilborn Engineering has provided more information to Pioneer Metals (TSE) which hopes to make a production decision by year-end for its Puffy Lake gold mine project 28 miles northeast of Flin Flon, Man.

The mine operated in the late 1980s at a rate of about 900 tonnes per day, but was closed because it did not achieve commercial production levels. The recent engineering study estimates the remaining mineral resource at the mine to be 1.48 million tonnes (proven and probable) averaging 7.5 grams gold per tonne (0.2 oz.), with an additional 673,000 tonnes of possible reserves averaging 7.01 grams.

The Puffy Lake mine was known for its coarse free gold which was reported to have made planning difficult by assay grade sampling alone. However, Pioneer noted that an analysis of the mined areas indicates the gold sent to the mill was within 1% of that predicted from surface drill holes.

The Kilborn study concluded that the problems encountered in the past can be mostly attributed to a premature startup, with a mill capacity far in excess of the mine’s ability to produce. Also cited was the lack of sufficient development which prevented the mining of zones in an orderly selective manner forcing production from areas predictably below cutoff grade. “This deposit was never subjected to a rigorous program of geological mapping and sampling before mining because of the constant need to supply the mill,” said Stewart Blusson, Pioneer’s vice-president of exploration. The costs and details of a renewed operation have not yet been worked out, but the report recommended a second opening closer to the mill with direct haulage, and a less labor-intensive, more efficient mining method. In the past, the flat-lying deposit was mined by a modified open stope mining method as well as some mechanized drift and slash. The most likely method to be used if the mine goes back into production would be some form of longhole open stoping.

A renewed operation would also require a good deal of preproduction development work. Despite this, and low gold prices, Pioneer believes it has the ability to finance a 500-tonne-per-day operation targeted to produce more than 40,000 oz. gold per year.