Crews work to pump grout to stabilize area above Marguerite mine in Unity after sinkhole tragedy

A cement-like grout is being pumped into strategically placed borings and down into the former Marguerite mine beneath Monday’s Union restaurant in Unity.

Starting around 8 a.m. Friday a steady stream of cement mixer trucks emptied their contents every five to seven minutes into a machine that pumps it far as 20 feet below the ground.

“It will go all the way into the voids underground, protect the ground from subsiding and protect these structures,” said Lauren Camarda, Pennsylvania Department of Environmental Protection spokesperson.

On a sunny Friday afternoon with temperatures in the mid-20s, Camarda showed TribLive where the mine is being filled. The bore holes surround the area where emergency and construction crews excavated the mine for four days before locating the body of Elizabeth Pollard, who had fallen into a sinkhole Dec. 2.

Pollard, 64, was a Jeannette native whose body was recovered Dec. 6 after the area around the sinkhole was excavated.

DEP officials said Ligonier Construction crews are digging between 12 and 16 bore holes across the restaurant property, with several strategically placed along the borders of the restaurant, itself. Each is being pumped with a cement-like grout mixture that will slowly spread out over a roughly 25-foot area as it hardens, forming wide pillars to support the earth above.

Camarda said work crews do not have a clear picture of the area they are filling in, and did not provide an estimate of how long it will take to do the work.

State police Trooper Steve Limani previously said remediation work of this kind can take a while.

“Our Bureau of Abandoned Mine Reclamation doesn’t usually go into mines, because in many situations it’s just too hazardous,” Camarda said. “They pump the grout in until it’s not possible to pump anymore.”

The grout will not necessarily completely fill the void left behind by mining, but it will create a much more extensive network of vertical supports, she said.

The filling work is taking place only on the restaurant property, and it is similar to an upcoming project in North Belle Vernon, where the DEP plans to spend $10.5 million in federal funds to stabilize old mines that lie beneath more than 200 homes. The Belle Vernon Area High School in Rostraver was damaged by mine subsidence in the 1970s, and several homes in North Belle Vernon were damaged in the 1980s.

While that work is taking place at no cost to residents, the various costs associated with the Unity search are still being tabulated.

It took four days to locate Pollard’s remains as first responders from Unity and Westmoreland County were joined by state police and DEP workers.

“We’re still calculating costs, determining the lost revenue and the lost income and talking with Ligonier (Construction) about the costs it had incurred in the digging it did at the site of the sinkhole,” said Unity Supervisor Mike O’Barto, board chairman, on Thursday.

Supervisors declared an emergency that will allow the township to apply for state reimbursement of the costs of the rescue and recovery operation.

The township is in the process of documenting all of those costs, including lost income from any volunteers whose jobs do not pay them for their response to the emergency and the money spent by Monday’s Union Restaurant to feed the first responders, O’Barto said.

“We’ve been working on it all week,” O’Barto said.

O’Barto praised the precise digging at the mine subsidence site by Ligonier Excavating in its use of an excavator to open access to the underground mine for the rescuers.

“They were like surgeons to get the body of Mrs. Pollard out of that mine shaft,” O’Barto said.

At Thursday’s supervisors meeting, officials held a moment of silence for Pollard. The Westmoreland County coroner said she died of head and torso injuries.

About six to seven Westmoreland County public safety officials staffed the search each day providing support for Unity fire crews, which served as the lead agency during the search and rescue operation, according to Bud Mertz, director of Westmoreland County Department of Public Safety.

The county’s former mobile 911 command center was also used because it is leased by Unity. The county’s new mobile 911 center was used Dec. 6, the day Pollard was recovered.The county’s hazmat team was also on hand throughout to monitor air quality in the mine and to coordinate with state officials.

Mertz said the county has not yet calculated the cost of its involvement in the search and rescue.

“We were there basically in a support role to Unity Township,” Mertz said. “They ran the operation.”

Pollard was a retiree who previously worked at Walmart in Greensburg and Unity and the former Toys R Us in Hempfield. She enjoyed flower gardening, crafts and her cats, according to her obituary.

Funeral and burial services were private.

Related:

• Monday's Union Restaurant reopens after playing 'vital' role in Elizabeth Pollard search
• Coroner: Unity woman died of head, torso injuries after fall into sinkhole
• Coal, once king in Pennsylvania, leaves behind abandoned mines that pose concerns
• Unity woman, victim of sinkhole tragedy, remembered for dedication to family, concern for neighbors
• Grief, relief felt as Unity woman's remains recovered from sinkhole
• Family holds out hope as search continues for missing Unity woman at sinkhole site

Rich Cholodofsky, Joe Napsha and Patrick Varine are TribLive staff writers. They can be reached at rcholodofsky@triblive.com, jnapsha@triblive.com and pvarine@triblive.com.