The Canadian and Alberta governments will establish a federal-provincial working group to accelerate remediation of oil sands tailings ponds, the Alberta government said on Wednesday, as investigations continue into an ongoing tailings leak at Imperial Oil's Kearl project.

Federal Environment Minister Steven Guilbeault and Alberta Environment Minister Sonya Savage met on Tuesday to discuss the incident at the 240,000 barrel-per-day Kearl mining project in northern Alberta.

Industrial wastewater containing toxins including arsenic and dissolved iron has been seeping from tailings ponds at Kearl since at least May last year. Last month, Imperial reported a separate leak of more than 5,000 cubic metres (1.3 million gallons) of tailings water from one of its holding ponds.

"The ministers also discussed accelerating collaboration on a long-term solution for the treatment and remediation of tailings ponds and will work to establish a federal-provincial working group to ensure this is developed as quickly as possible," a readout of the meeting released on Wednesday said.

Alberta's oil sands mines produce vast quantities of toxic tailings water. Total volumes reached 1.36 trillion cubic meters in 2020, according to the Alberta Energy Regulator.

Unlike other extractive industries in Canada, oil sands firms are not allowed to release treated tailings water but Ottawa is working on new regulations, expected in 2025, to govern how treated tailings could be safely released into the Athabasca River.

Calgary-based Imperial, majority-owned by Exxon Mobil Corp, and the AER have both been criticized for failing to properly disclose the Kearl tailings leak to local communities. 

Alberta has sent officials to Kearl to conduct independent water sampling, in addition to monitoring by the AER and Imperial, according to the meeting readout. Guilbeault and Savage agreed to share testing results and review information exchange processes.

Last week, federal inspectors said the leak is harmful to wildlife and ordered Imperial to take immediate action to contain the seepage.

(Reporting by Nia Williams in British Columbia; editing by Emelia Sithole-Matarise and Marguerita Choy)