WILLIAMS LAKE, B.C. - An advocacy group will be back in provincial court in Williams Lake, B.C., today pursuing private prosecution against the province and a mining company over the collapse of the Mount Polley tailings dam.

MiningWatch Canada launched the case last fall, saying the province and the Mount Polley Mining Corp. violated the Fisheries Act when a tailings pond collapsed at the copper and gold mine in August 2014.

The group alleges serious harm was done to fish and the environment when the dam's failure sent 25 million cubic metres of wastewater gushing into streams and waterways in B.C.'s Interior.

The allegations have not been proven in court and in January, Crown lawyer Alexander Clarkson argued there is no prospect of conviction in the case.

Clarkson said the private prosecution is not in the public interest because the B.C. Conservation Officer Service, Environment Canada and Fisheries and Oceans Canada are already investigating, and their findings could be considered for the charge approval process.

MiningWatch Canada spokesman Ugo Lapointe says the group expects the Crown will ask for a stay of proceedings today, and if so, they will pressure the Crown and federal government to lay their own charges in the case.