VANCOUVER (miningweekly.com) – Continuous successful exploration drilling over the past two years has prompted TSX- and NYSE-listed precious metals explorer Seabridge Gold to re-evaluate its approach to mining at the flagship Kerr, Mitchell and Sulphurets project (KSM), in north-western British Columbia.

Based on the expectation of a substantial resource addition at higher grades of gold and copper, Seabridge now intends to investigate the start of mining at the Iron Cap deposit sooner than set out in the KSM mine plan, which currently proposes developing Iron Cap after the Mitchell, Kerr and Sulphurets deposits.

According to the November 2016 KSM technical report, the Iron Cap deposit was the last deposit of four to be mined, with production slated to start in year 32 of the current 50-plus-year mine plan.

"Iron Cap has some advantages. It's situated in the same valley as key planned infrastructure and is immediately adjacent to the proposed tunnel conveying ore to the processing plant. Kerr, on the other hand, is in the next valley approximately 10 km away, requiring significant additional infrastructure to develop and transport its ore to the mill," chairperson and CEO Rudi Fronk said.

Previously, Seabridge considered the Iron Cap deposit too small and of too low a grade to warrant earlier development.

Seabridge now believes that exploiting Iron Cap earlier has the potential to significantly improve KSM's economics on the back of deferring significant capital costs and expediting better grades into the mine sequence.

"We are planning another programme at Iron Cap this year to expand the known zones of mineralisation, fill in some of the holes in past drilling and move these newly defined intervals towards reserve definition," Fronk advised.

The Iron Cap deposit has been permitted for block cave underground mining within the environmental assessment approved by the British Columbia and Canadian governments in 2014.

Among the highlights from the 2017 Iron Cap drill programme were Hole IC-17-66, which intersected an interval of 63.6 m grading 4.8 g/t gold equivalent; Hole IC-17-70, which encountered an interval of 925 m grading 1.49 g/t gold equivalent, which included 491 m and 104.6 m intervals grading 2 g/t and 2.99 g/t gold equivalent, respectively; and Hole IC-17-72, which returned an interval of 858.1 m grading 1.71 g/t gold equivalent, including a 113.3 m interval grading 5.56 g/t gold equivalent.

The company noted that the reported equivalent grades were based on price assumptions of $1 275/oz of gold, $3/lb for copper and $17.50/oz of silver.

Iron Cap currently hosts compliant measured and indicated resources of 346 800 t, grading 0.51 g/t gold, for 5.69-million ounces of yellow metal.