Maryland Midland Railway Inc. has closed part of its freight line after workers discovered a 40-foot by 12-foot sinkhole about 6 feet from its tracks behind McGregor Printing Corp. between Westminster and New Windsor.
Work crews were scheduled to return today to begin filling the hole with crushed stone.
"It could have been dangerous if more of it [soil] had given way under the tracks," Maryland Midland President Paul D. Denton said.
The hole was among the deepest sinkholes found recently in Carroll, county hydrogeologist Thomas Devilbiss said.
"It's been forming for quite some time," possibly years, he said.
The sinkhole was located several miles from where a Taneytown man died in March after his van plunged into an 18-foot-deep sinkhole on Route 31 near Medford Road.
Sinkholes are common in the Wakefield Valley area because it is rich with limestone, a porous rock that easily moves water and mud, which erodes soil. Limestone mining also may contribute to sinkholes. Three quarry companies own land in the area; Genstar Stone Products Co. is the only one with a mining pit.
Mr. Devilbiss said it is hard to determine why a sinkhole forms. Weather and drainage also are factors, he said.
A Maryland Midland crew discovered the sinkhole in its right-of-way on the north side of the tracks behind McGregor Printing on Saturday afternoon, said Roger Gettel, a railway track worker from Chambersburg, Pa.
Mr. Denton said an EnterTRAINment line scheduled to run west of Westminster over the weekend was rerouted from Westminster east to Glyndon. A freight train scheduled to run on the line last night was canceled, he said.
Gary Smith, a track department worker from Cavetown, Md., said he was at the site much of the day yesterday to ensure that no one got too close to the hole. In late afternoon, an employee from Thomas, Bennett & Hunter Inc. of Westminster used a front-end loader to dig out the side of the hole nearest the McGregor building to determine if the hole would sink farther. It didn't, but the digging caused the hole to extend to the edge of the train track ties.
Workers surrounded the hole with 4-foot-high fencing.
The railroad has had to fill at least two other sinkholes in its right-of-way in Wakefield Valley in the past year.
Mr. Denton said he didn't know how much it would cost to fix the 40-foot sinkhole.
"It'll be expensive," he said.
The railway has 67 miles of track in Baltimore, Carroll, Frederick and Washington counties.