Heavy machinery and sound-monitoring equipment are being used in the search for a Pennsylvania grandmother believed to have fallen through a sinkhole deep into fragile, unstable ground while searching Monday for her cat, authorities said.
Amid danger of a collapse, rescuers have been pumping water through a long-abandoned mine at the site to clear out debris, then remove it with a vacuum, to make it easier to see what is underground, Pennsylvania State Police said early Wednesday.
“The integrity of that mine is starting to become compromised,” Trooper Steve Limani said in a news conference.
Know the news with the 7NEWS app: Download today 
Rescuers hope Elizabeth Pollard, 64, is still alive in an air pocket, officials have said, noting the hole has plenty of oxygen and is about 55 degrees, far warmer than above ground. And though shifting ground is slowing the search, state police will not stop until they have answers, they’ve said.
Two abandoned mines are near the sinkhole, a federal database shows. They are designated to “pose the highest danger to citizens’ lives” due to land safety and environmental concerns, according to the National Association of Abandoned Mine Land Programs.
Sinkholes usually form due to groundwater slowly eroding the underground rock that holds soil together, and Pennsylvania is particularly prone to sinkhole damage because of its limestone bedrock, according to the US Geological Survey.
“There’s been nothing that said she is not alive or she could not possibly have survived,” Limani said of Pollard. “There’s nothing that said 100% definitively it couldn’t have happened. And until that 100% happens, how could I say it’s any other way?”
“Let’s be honest,” he added, “we need to get a little bit lucky.”
64-year-old last seen behind restaurant
Police got a phone call around 1 a.m. Tuesday from a relative of Pollard who said the grandmother, with her 5-year-old granddaughter, had left in a car to look for her cat the prior afternoon and had not been heard from since, State Police said Tuesday.
Pollard was last seen around 5 p.m. Monday in Marguerite, an unincorporated area of Unity Township, Limani said, in a part of southwestern Pennsylvania dotted with old coal mines.
Police out looking for the woman discovered her vehicle – with her granddaughter inside – parked near a restaurant.
A fresh, deep sinkhole was just steps away.
“We, at that point in time, realized that this could be a very bad situation,” Limani said.
The granddaughter, who’d been in the car for nearly 12 hours in below-freezing temperatures, was unharmed, Limani said. But the girl, now with her parents, couldn’t give police any details about what happened.
“She was just a 5-year-old girl that was waiting in the car for her grandmother to come back,” he said.
No sounds picked up by monitors in search
The sinkhole, which was about 15 to 20 feet from Pollard’s vehicle, appears to be about the size of a manhole at the surface but gets much wider below ground, making search and rescue efforts challenging, Limani said.
The sinkhole likely appeared at some point Monday, officials said.
“That hole wasn’t there earlier in the day,” Limani said. “It’s close enough to the building that somebody would have seen it.”
“There is a very thin layer of earth, and to be honest with you, it appears to be mostly just grass interwoven where she had stepped,” he said.
Credit: State Police Trooper Stephen Lim/Pennsylvania State Police/AP
While no sounds have been picked up by monitoring equipment, the rescue teams spotted a shoe in the sinkhole Tuesday using a camera, Pleasant Valley Volunteer Fire Company Chief John Bacha said.
“Let’s just say it’s a modern shoe, not something you would find in a coal mine in Marguerite in 1940,” he said.
Thousands of sinkholes in Pennsylvania
The sinkhole where Pollard is believed to have fallen is in an area with limestone bedrock and had almost no ground left, state police said.
Bacha took an initial look in the hole Tuesday using a ladder and a harness but did not spot Pollard, he said. “You couldn’t even get close enough to the hole because of the way it was undermined,” he said.
“A lot of the little villages around here are old coal patch towns,” he said. “(It’s) very common to find a lot of mines in these areas, obviously a concern to have these mine subsidence issues.”
The state Department of Environmental Protection, or DEP, which regulates the state’s operational and abandoned mines, is on the scene, spokesperson Lauren Camarda said.
“Once police and emergency response have cleared the scene, DEP’s Bureau of Abandoned Mine Reclamation will investigate the site to determine if this issue is the result of historic mine subsidence,” she said in a Tuesday statement.
“Each year, DEP works to address historic abandoned mine land features across the Commonwealth with available federal funding and address emergencies as they arise,” Camarda added.
As of 2020, there were over 3,600 sinkholes in Pennsylvania, according to data collected by researchers at Millersville University.
“Sinkholes are dramatic because the land usually stays intact for a while until the underground spaces just get too big,” the US Geological Survey says.