The leak happened at the Giant Mine on the ingraham trail, just outside of yellowknife, in the Northern Territories of Canada.

One worker at the site, which has been undergoing remediation since about 2007, needed to be washed down after the spill – but has so far shown no other ill effects.

The scheme which is costing more than $200m of taxpayer’s money, is using the ‘frozen block alternative’ remediation, which involves permanently freezing the arsenic in place to stop contaminated water seeping out.

Overall, the scheme will contain and store underground a total of 237,000tonnes of arsenic trioxide dust.

Earlier this year, as part of the remediation, workers began drilling bore hole through which they would use to begin the freezing process.

However, in a report released last week the Indian and Northern Affairs Department, said the incident on October 22 released arsenic dust over a five to 10metre area.

The mine, in the Northern Territories

A recent arsenic spill at the defunct Giant Mine near Yellowknife is raising concerns about safety and the reporting of spills at mine sites.

Drilling at the former gold mine has been stopped while the federal government awaits results from soil, water and air-quality tests done since the spill last week.

The company that was working at the site at the time, the Deton’Cho Nuna joint venture, was asked for a comment but has not responded.

Luke Walsh

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