The city confirmed it is working on a new location for a public boat launch after the Giant Mine Project Team provided an update to council on remediation plans, Jan. 21.
Natalie Plato, deputy director presented council with an overview of plans for the next decade on where next steps lie with the Giant Mine Remediation project. Plato explained that the team is submitting a water licence to the Mackenzie Valley Land and Water Board on April 1 and following an expected 18-month wait, is hoping to proceed with the next phase of the project in August 2020.
This will begin with the demolition of the former Giant Mine townsite in 2021, followed by soil remediation and the near dredging of the Northwest Yellowknife Bay in 2023 where the city’s largest public boat launch and Great Slave Sailing Club are situated.
As Yellowknifer has reported, Plato explained that the work will mean cutting off access to the public for much of the next decade leading up to the goal of a 2030 completion for that phase. The long-term goal is to eventually bring the area back to use again, she said.
City councillor Robin Williams asked what “preliminary” plans are in the works to address concerns from the public about a lack of access to the bay. He said the Great Slave Sailing Club had contacted councillors about the issue and the public has expressed concern about the lack of access during expected remediation work in the area.
“It is early days and we have had conversations with the Giant Mine remediation team in 2018 around this,” said Sheila Bassi-Kellett, noting that the Great Slave Sailing Club, Yellowknife Historical Society and Giant Mine boat launch are three keys areas of concern. “We are … exploring opportunities for a boat launch and a marine area. There are a lot of moving pieces, but we hope for more finite plans to be able to consult with key stakeholders on this year.”
Bassi-Kellett said discussions are ongoing with the Yellowknives Dene First Nation as well as the Akaitcho government, but could not commit on when a decision would be made with replacing the boat launch or Sailing Club mooring field.
“We do have ideas we are exploring and we will be coming back with that,” she told council.
As for the Yellowknife Historical Society and its museum in the works, Plato said in part, because significant federal dollars have been invested in the structure, it is expected to remain accessible to the public. Plato said while there are concerns that the museum will be “an island” with no other lease tenants in the area for tourists, the project team remains committed to not impacting plans for that site.
“We are still working out what limitations will work,” Plato said, especially after Baker Creek realignment takes place later in the decade.
Plato and her project team colleague Aaron Braumberger explained plans for the coming decade. Plato provided some detail about the high level activities planned for the site including underground stabilization, water level control and freezing and maintaining 14 arsenic chambers; constructing a fence around the geographic “core area” of the remediation site which will see the construction of a new, year-round permanent water treatment plant and a non-hazardous waste landfill.
Plato also discussed plans to upgrade the Giant Mine townsite area to residential standards for arsenic remediation.
“We heard through multiple engagement sessions that the townsite area should be cleaned up to residential standards,” Plato said. “The townsite’s future use is unknown, but to give the most flexibility … we were asked by multiple people, including city staff, to remediate to residential standards. We have agreed to do that.”
Other areas that received direct mine use – such as landfills, roads and dumps will be upgraded to a lesser industrial standard, she said.
Plato said eight open pits, similar to the four tailings ponds on site, will require quarrying and waste rock infill and one of the goals will to be protect those areas from water.
“If the pits flood, water could get into the underground, which is something we don’t want,” she said.
Baker Creek, which is to see slight realignment in 2028, will be widened to help with flood control and will see a remediation effort from Baker Pond all the way to the mouth of the creek as the area is contaminated, Plato said.
Plato also said an outfall pipe to send treated water for discharge into Northwest Yellowknife Bay, will be constructed near the Great Slave Sailing Club.
Quantitative Risk Assessment
Coun. Shauna Morgan pressed Plato on if there was an emergency plan and communications plan in place should the worst-case scenario happen on site, such as a breach of a tailings pond and how it might impact the city’s plans for water intake in Back Bay.
Plato said the federal government is working on a “quantitative risk assessment” which should be completed by the end of this fiscal year and which will give a better idea of what risks exist and how to reduce them.
“Looking at a tailings failure and what it would do to Yellowknife’s water supply is certainly on our list of risks to evaluate and it is going to take a look quantitatively and getting a numerical value and looking at mitigations to lower that number,” Plato said, adding that emergency plans exist on site, but more work needs to be done to plan how to communicate with the public.