On Sunday Alaska Native and Canadian First Nations groups will mark the first anniversary of the Mount Polley tailings dam collapse in a ceremony on the Stikine River.

On Aug. 4, 2014, a rupture in the tailings dam servicing the British Columbia mine released billions of gallons of metals-tainted effluent into waters that fed into the salmon-rich Fraser River system.

Earlier this month the mine’s owner, Imperial Metals, received a restricted permit from the provincial government allowing it to reopen Mt. Polley, using an alternate tailings operation. The company expects production to resume next month with limited staff and operations and to be back to full capacity within a year.

During Sunday’s ceremony, participants will bless waters of the Stikine River, which regionally is a major transboundary river and an important source of salmon. The opening of the Red Chris mine—also owned and operated by Imperial Metals—last month near the river’s headwaters has caused concern for those living downstream.

Red Chris will be a large-scale operation, anticipated to produce copper and gold at more than 33,000 tons per day over three decades. Worrying to commercial fishermen, subsistence users and other residents who depend on the Stikine River, the mine’s waste will also be acid-generating in nature.

The risk of long-term water pollution and the possibility of catastrophe similar to that at Mt. Polley has caused an unlikely collaboration to form between industry, tribal and environmental groups, as half a dozen large-scale gold and copper mines are being developed near transboundary watersheds.

Wrangell Cooperative Association will host the ceremony on Chief Shakes Island. A procession through town will start at 1 p.m., followed by a blessing of local waters in front of the island’s restored tribal house. After a musical presentation, guest speakers have been invited to make remarks, including Iskut First Nation spokesperson Oscar Dennis and Northern Shuswap Tribal Council mining response coordinator Jacinda Mack.

“This is a tremendous opportunity for the Tribe and Wrangell to host such an event,” Aaron Angerman, WCA tribal administrator, said in a release. “Ceremonies like these should be happening in all Southeast Alaska communities, especially those surrounding transboundary rivers. Let your voices be heard and let’s get the International Joint Commission to enforce the Boundary Water Treaty and protect our shared waters.”

A working dinner will follow the ceremony, allowing tribal, state and federal government officials, conservation organizers and concerned community members the opportunity to ask questions, voice concerns and strategize next steps for working together.

The public is invited to attend the ceremony on August 2. For more information, please contact the tribal office at 874-4304 or WCATribe@gmail.com.