OXFORD, N.S. — It won’t be long before Oxford residents learn when and if a sinkhole that developed last summer in the Lions Park can be repaired.
Cumberland County EMO co-ordinator Mike Johnson said the geophysical testing of the sinkhole has been completed and the results of that work will be shared with stakeholders and then made public at a meeting in the community.
A date for the meeting has yet to be set.
“The preliminary report from the data collected is indicating it is very good data,” Johnson told the Amherst News. “We would have like the data to be a little bit deeper because it didn’t get down to the gypsum that we wanted to see.”
In April, Cumberland-Colchester MP Bill Casey announced $68,500 in funding for the federal share of the geophysical testing through ACOA’s Innovative Communities Fund. GHD Ltd. was hired to conduct the testing including completing an image of the subsurface without digging, including electrical resistivity and seismic testing looking for rocks and potential voids.
The geophysical testing was required after ground penetrating radar didn’t go deep enough.
“We’re expecting the final report by the end of July and shortly after that we will meet with the stakeholders, all of those businesses and agencies that would be impacted by the results of the study,” Johnson said. “It’s after that, that we will have the public meeting.”
Until those results are known, little can be done with the sinkhole that formed in the park at this time last year – first with a small hole near the Lions building that was followed in late August by a massive sinkhole that forced the closure of the park and the building as well as the moving of playground equipment from the property.
The sinkhole is located in what’s called the Windsor Group that occurs throughout the province in places like Windsor, Falmouth, Cape Breton and elsewhere. Gypsum is part of that geological feature and it’s a mineral prone to sinkhole development because it’s soft rock that can dissolve through either groundwater or surface runoff.
While the sinkhole rapidly grew in size during late August and into September 2018, it’s development slowed. It was approximately 32.6 metres by 38.7 metres at that time and hasn’t really changed much since then.
That doesn’t mean it’s quiet.
“Stable is a word I’d be hesitant to use,” Johnson said. “It’s continued to slump inward. The sides of the sinkhole have been very vertical, straight up and down. From the freezing and thawing cycle, erosion and rainfall the sides are beginning to slump in so that there’s a bit of slope along the edge, but it’s still very steep.”
The water in the hole, he said, has become to settle and has become more clear. However, it’s important for people to realize it’s still very dangerous to enter the park and approach the hole.
“It’s still a hazardous area and there’s still risk,” Johnson said. “That’s why access is still restricted.”
Johnson said the sinkhole is “relatively dormant” but there have been some new cracks in the pavement since last fall.
The testing, he said, was good but didn’t answer all the questions and may have raised a few more questions. He wasn’t prepared, however, to go into what those questions would be saying it will all come out when the report is shared with the stakeholders and the public.
“The answers aren’t quite clear, but it does give us the ability to make some general statements in due time,” he said.
