The Tk’emlúps te Secwépemc, at a presentation on Thursday (July 15), at the Coast Kamloops Hotel and Conference Centre, shared new details of its ground-penetrating radar (GPR) survey.
Ground-penetrating radar expert Dr. Sarah Beaulieu of the University of the Fraser Valley led the search south of the school building, not far from the South Thompson River, finding signs of 200 probable graves.
“With ground-penetrating radar, we can never say definitely they are human remains until you excavate, which is why we need to pull back a little bit and say they are probable burials, they are targets of interest,” Beaulieu said. “They have multiple signatures that present as burials, but because of that, we have to say they are probable until one excavates.”
Beaulieu has years of experience in the use of the technology, having surveyed municipal and Indigenous cemeteries across Canada, along with Second World War internment sites.
The ground-penetrating radar search was conducted between May 21 and May 24 on two acres of an apple orchard near the Secwépemc Museum and Heritage Park just south of the brick building that housed the school, which operated from 1890 to 1977.
Recollections of children as young as six years old being woken up in the middle of the night to dig holes for burials in the apple orchard and human bones found in the same area were among the factors that lead to the area being chosen for a GPR survey, Beaulieu said.
A juvenile rib bone was found by a tourist and brought to the band in the early 2000s, later being identified as human. In the late 1990s or 2000s, a child’s tooth was excavated from a shovel test pit in the area during an impact assessment by Simon Fraser University’s archaeological department.
“A juvenile tooth is not an indicator of loss of life, but given both discoveries, the possibility should not be discounted,” Beaulieu said at Thursday’s press conference.
When the band broke the news in May, it said there were remains of children as young as three years of age.
Beaulieu told KTW that notion came from residential school survivors who told of people as young as three being taken to the school. The GPR survey can’t indicate age, but showed signs of smaller anomalies in shallower areas that could track with those accounts.
In the presentation of her findings, Beaulieu said the GPR survey showed common features of burial sites, such as convex patterns of anomalies at the top of and vertical patterns at the sides of the possible graves. While these features aren’t exclusive to burials, in areas where they are expected, they can add to the likelihood of their existence, Beaulieu said.
Adding to the supporting evidence of graves were surface depressions correlating with the subsurface anomalies observed in the GPR data and an east to west configuration of those anomalies consistent with Christian burial sites, Beaulieu said.
On May 27, Tk’emlúps Kúpki7 (Chief) Rosanne Casimir said 215 unmarked graves had been located using the technology, but on Thursday, Beaulieu said that number was reduced following her initial survey when taking into account records of previous archaeological work and construction that could have impacted the results.
With 160 acres of land at the Kamloops Indian Residential School landscape yet to be probed, Beaulieu said there may be more probable graves found, with total number at this point unknown.
Beaulieu told reporters the process of determining the number of graves on the survey involved ruling out different anomalies, such as root systems, stones and other items under the soil that didn’t present as a potential burial.
Adding to the likelihood of these soil anomalies being children’s graves was that the majority of them were 0.7 to 0.8 metres (less than three feet) below the surface, which fits with the testimony of children having to dig graves and the depth of burials for juveniles, Beaulieu said.
Beaulieu told KTW she found no sign under the surface to indicate there may have been gravestones in place at one point.
In reviewing GPR data, Beaulieu looks at reflective or refractive patterns on a screen.
“GPR it looks like a glorified lawnmower system,” Beaulieu said.
The machine emits short, electromagnetic pulses that bounce off whatever is in the soil, reflecting or refracting depending on with what it comes into contact. As the pulses move along a line, it forms vectors placed together, producing a splice of what’s in the ground, measuring where the soil disturbance starts and where it stops.
In her presentation, Beaulieu noted remote sensing such as GPR isn’t necessary to know Indigenous children went missing from residential schools as the evidence has existed in government and church archives and in testimony from survivors. In addition, Canada’s Truth and Reconciliation report identified between 4,000 and 6,000 missing children.