SRK Consulting have uploaded a seminar from their second Mining Seminar Series held in January 2015 in Vancouver, British Columbia, Canada. Stephen Day (Principal Geochemist) presented a talk titled “Segregating waste rock to prevent acid rock drainage”. Acid rock drainage is a major problem principally linked to the oxidation of pyrite.
“Mines have been proactively managing waste rock to address acid rock drainage (ARD) potential since the 1990s. The typical management approach leads to segregation of rock that has potential for ARD generation (PAG) from rock that is non-PAG.”
“The PAG rock is then disposed of appropriately to limit ARD (for example, underwater in an impoundment or completed pit), whereas non-PAG rock may be suitable for conventional disposal or use as construction fill, such as for a tailings dam.
Despite pleas from Coalition of Victims of Pyrrhotite (CVAP) in Canada, SNC-Lavalin (the main defendant in the recent pyrrhotite trial) have stated that they will appeal the pyrrhotite judgement, Le Nouvelliste reported yesterday (10.07.14).
In the Superior Court judgement, SNC-Lavalin along with their geologist Alain Blanchette, had been found responsible for 70 % of the pyrrhotite problem. Le Nouvelliste reports that the CVAP spokesman, Yvon Boivin, was “bitterly disappointed” by the decision to appeal, but was continuing with plans to promote the boycotting of SNC-Lavalin. Disappointment was also expressed at the news on the CVAP Facebook page.… Read the rest
In the early 2000s around 30 homes suffered pyrrhotite problems in the Trois Rivieres area of Quebec, relating to aggregates from a small quarry that only operated for a short time (Maher, 2013). New problems came to light in the late 2000s, with around 1700 residential buildings now suspected of having pyrrhotite problems. A major legal case relating to the more recent events has concluded and the judge has delivered the verdict.
Canadian pyrrhotite problem historical summary
A summary of the events related to pyrrhotite in Canada can be found here.… Read the rest