A giant sinkhole in a Nova Scotia town has already swallowed several trees and boulders, and concern is growing as it inches closer to several nearby businesses.

A gas station, coffee shop, Lions Club and road are situated close to the gaping, water-filled hole in Oxford, N.S. Officials have used neon spray paint to mark new cracks in a parking lot near the hole.

By Tuesday, the sinkhole was measured at 34 metres long by 28 metres wide. It’s unclear just how deep the hole is, or when it will stop growing.

Members of the Oxford Lions Club removed play structures from the park on Monday as they appeared to lean. There are concerns that the Lions Club building might soon plummet into the growing hole.

Mike Johnson, Cumberland County’s emergency management office coordinator, said the gas station is being kept in the loop in the event that they need to “pump their tanks dry and remove any hazardous material.”

“We’re not there at this point,” he said.

Officials are exploring ways to measure the sinkhole’s growth and trajectory, including high-precision surveying to monitor changes in elevation. Radar technology capable of penetrating the ground is also on the table.

Locals are flocking to the site to get a glimpse of the unusual phenomenon. Security has been hired around the clock to make sure onlookers don’t get too close.

Linda Cloney, deputy clerk for Oxford County, said safety measures have been taken to protect workers who need to access off-limits areas.

“Everyone is going in with a pair if they’re going around to look everything over. And also we have our personal flotation devices set up there by the tree there to throw in if we need to,” Cloney told CTV Atlantic.

A sinkhole is formed when water dissolves underground rock or minerals, thereby carving deep fissures underground. In Nova Scotia, about 85 per cent of sinkholes involve gypsum, a soft sulfate mineral, according to Robert Ryan, Nova Scotia manager of mineral resource evaluation.

Because the sinkhole is so deep, Ryan says attempts to fill it would be futile.

“You could put material in there but chances are it’ll end up down in the river,” Ryan said.

Besides gypsum, limestone and salt have also been linked to sinkholes in Nova Scotia. There’s no way to know for sure when a sinkhole could form, but understanding the makeup of bedrock is a helpful precaution, says Ian Spooner, a professor with Acadia University’s Department of Earth and Environmental Science.

“There’s excellent maps in Nova Scotia and we know the rock type in which sinkholes form most commonly. We know where those rocks are,” Spooner said.

With a report from CTV Atlantic’s Bruce Frisko and Jonathan MacInnis

More video: A large rock and tree slide into the ever-growing sinkhole in #Oxford #NS . It’s now over 100 feet in diameter! Located at Lions Park across from the Tim’s, Irving and giant blueberry it’s creating some traffic problems. Also 24/7 security for safety. @CTVAtlantic pic.twitter.com/oZCN7C7z6s — Paul Creelman (@PaulCreelmanCTV) August 27, 2018