The Giant Mine Oversight Board is calling for arsenic warning signs in Ndilo after a Yellowknives Dene First Nation chief asked for them at the board’s public meeting in May.
“While it is known that there are ‘hot spots’ of particularly high concentrations (of arsenic) in the community, the location of these hot spots is not commonly known and people, especially children, may be inadvertently exposed to arsenic trioxide contamination,” Kathy Racher, the board’s chair, wrote in a May 24 letter to the regional director of Indigenous and Northern Affairs Canada (INAC) and the GNWT’s deputy minister of health.
Racher states that the board “strongly recommends” the the federal and territorial governments cooperate in putting up signs as soon as possible, and create a plan to remediate the contaminated soil.
Elevated levels of arsenic are present in Ndilo’s soil as a result of past gold mining at Giant Mine, which processed ore on site from 1948 until 1999. It is estimated that about 20,000 tonnes of arsenic were released from Giant’s roaster into the atmosphere during that span.
In advance of remediation efforts at Giant Mine, the federal government commissioned a report on arsenic levels in Ndilo, Dettah and Yellowknife and the “likelihood of potential risks” to human health, wildlife and plants from exposure.
The nearly 2,500-page Human Health and Ecological Risk Assessment, dated January 2018, found that of the communities studied, arsenic levels were highest in Ndilo.
The report identified several arsenic “hot spots” in Ndilo soil, including near the school.
In the risk assessment, a hot spot generally refers to an area where the arsenic concentration is greater than 900 milligrams per kilogram of soil (mg/kg), Myranda Bolstad, spokesperson for the Giant Mine Remediation Project, explained in a May 24 email.
Average levels of arsenic in soil in Canada range from 4.8 to 13.6 mg/kg, according to Health Canada.
In an interview last month, Andre Corriveau, the Northwest Territories’ chief public health officer, said there is not a great need for signs in Ndilo because the potential for human exposure is low.
“There’s a few hot spots in the ground, but unless you eat the dirt, it’s not a source of exposure,” he said
Typically, people are exposed to arsenic by ingesting it.
“But it’s important for the community to be aware (of the hot spots), maybe through a map, so that people who want to know can look at it,” added Corriveau.
He said there should be a plan to remediate the soil in Ndilo.
Health Canada states that exposure from soil is “potentially significant” in residential neighbourhoods that have been built in contaminated areas.
While exposure through soil is unlikely to be an issue for adults, states the department, “hand-to-mouth behaviour and intentional ingestion may result in significant exposure for young children.”
On May 15, Ndilo Chief Ernest Betsina stood at a public meeting hosted by the Giant Mine Oversight Board and denounced the territorial and federal governments’ handling of communications surrounding arsenic in Ndilo soil.
“I want to know: how big is this area and how contaminated is it?” Betsina said. “Will somebody tell me that and will somebody tell my people how much area is contaminated?”
Betsina told the board that Ottawa and the GNWT have each said the other is responsible for alerting residents to arsenic contamination in Ndilo.
He appealed to the board to identify the hot spots and put up signs so that Ndilo residents can keep clear of these areas.
“Somebody take responsibility and please report to chief and council,” he said.
The Giant Mine Oversight Board’s mandate is limited to the Giant Mine site.
The GNWT has said land management in Ndilo is Ottawa’s responsibility.
Natalie Plato, deputy director of the federally-run Giant Mine Remediation Project, said at the May 15 meeting that Matt Spence, regional director for Indigenous and Northern Affairs, was best positioned to answer Betsina’s questions. Spence, who wasn’t present at the meeting, later said he was out of town on the day of the board meeting.
Yellowknifer first requested an interview with Spence on May 23. An interview was not granted until Monday (see sidebar).
Neither Betsina nor a representative from the department of Lands at Yellowknives Dene First Nation was available for an interview before Wednesday’s print deadline.
No signs for Ndilo but feds promise remediation
The federal government will not put up contamination warning signs in Ndilo, and is instead devising a “more permanent solution to the problem” of the arsenic hot spot near the community’s school.
“We’re going to deal with the problem and therefore we won’t need signs, because we will have remediated that area of high concentration,” Matt Spence, regional director general for Indigenous and Northern Affairs (INAC), said on Monday.
Spence couldn’t say when remediation of the soil near the school would begin. First, he said, he wants to get a better understanding of the size of the hot spot, and discuss remediation options with the community.
“We’d like to get it done as soon as possible,” he said.
Specialists are currently exploring different ways to address the elevated arsenic levels in the soil near the school.
Spence said he and Andre Corriveau, the Northwest Territories’ chief public health officer, met with Ernest Betsina, chief of the Yellowknives Dene First Nation in Ndilo, on June 1.
The two men will return to Ndilo to follow up on options for soil remediation on June 19.
Spence maintained the risk to human health from arsenic exposure in Ndilo is low.
He said the hot spot near the school is in a wooded area that “wouldn’t be an area that I would see children playing in normally.”
Arsenic hot spots in Ndilo were first identified in an INAC-funded report by Stantec and the Det’on Cho Corporation, the economic development arm of the Yellowknives Dene First Nation, in 2014, Spence said.
After that study came out, INAC launched the Human Health and Ecological Risk Assessment to determine the risks to people of elevated arsenic levels in locations around the Giant Mine site, said Natalie Plato, deputy director of the Giant Mine Remediation Project.
That risk assessment was published in January.
“We have a very good idea of what the levels are at Ndilo and INAC has a specific responsibility for remediation of higher contamination at Ndilo because we have a relationship with the Indigenous community and it’s Crown land,” said Spence.
The Yellowknives Dene First Nation has requested a formal apology and compensation from Canada for harms caused by operations at Giant Mine.
Both the Giant Mine Oversight Board and the territorial government have endorsed this request.
Spence said INAC is hoping to talk to the Yellowknives Dene First Nation in the coming months and “come to an agreement on an approach.”