With what sounded like a muffled thunderclap in the distance, 25,000 tons of rock crashed to the ground yesterday afternoon in a billowy cloud of dust near the banks of the Susquehanna River.
It took less than a second, and thousands of people cheered.
It's not every day that one gets to see 14,700 pounds of explosives shear the side off a stone wall.
"I used to camp out here, do some hunting and fishing and climb the cliffs when I was a young," said Bob Einwachter, 69, as he videotaped the bulldozers, barges and stone crushers spread out along 600 acres of a stone quarry in Havre de Grace.
"I don't recognize it anymore," said Einwachter, a Pittsburgh resident who left the waterfront town 50 years ago. "It's just amazing."
For the fifth year in a row, the Arundel Sand & Gravel Co. quarry in Harford County opened to the public and wowed visitors with its gigantic mounds of rock and sand, 18-foot-high loaders and a 335-foot pit that looked like a small canyon.
Three million tons of stone are processed at the site yearly and shipped by land and bay up and down the East Coast to build roads, tunnels and cinder blocks for buildings.
Stone from the quarry, which has been mined since 1905, was used to build everything from the Fort McHenry Tunnel to the Maryland monument at the Civil War battlefield at Gettysburg, Pa.
Peering over the edge of the quarry cliff, which overlooks the river and the Millard E. Tydings Memorial Bridge on Interstate 95, Steve Powell pointed to the deep, jagged stone steps that have been carved into the edge of the hill over the last several years. Each step is about 40 feet deep -- the work of thousands of pounds of ammonium nitrate fuel oil, the same explosive used in the Oklahoma City bombing in 1995.
"There's a saying around here that goes, 'If it can't be grown, it has to be mined,' " said Powell, vice president of operations at Arundel Quarry. "Your whole quality of life comes from the ground. The metal in cars, plastic and buildings, it all came from dust, from mining. You wouldn't put a man on the moon without some type of mining.
"All we're trying to do is educate and answer any questions that the neighbors and communities around us may have," Powell said. "We want to take the mystery out of this place."
Men, women and children climbed aboard several yellow school buses that wound their way down dirt roads with several of Arundel Quarry's 77 workers.
Some learned about the goats named Tina, Naomi and Mikey that roam freely through the quarry.
Yesterday was Dave Beam's third time on the tour. His four children, ages 2 to 7, get a kick out of the place, but his smile is wider than any of theirs.
"I want a job here," said a grinning Beam, 36, who came with his family from Baltimore. "We'd miss Opening Day of baseball for this."
The free event costs the quarry about $30,000 a year for food and entertainment, but is worth every cent for the community relations, Powell said.
For years, the company fielded complaints from residents who feared the mining would ruin water wells, cause cancer and rattle the walls of their homes. There was also much public outcry over quarry dust that residents said ruined the scenic view of the river.
Arundel Quarry stepped up efforts to quell complaints. Neighbors are called when blasting begins, Powell said. Inspectors visit houses to assess complaints about damage. And trucks from the quarry are wetted down to reduce dust clouds along neighborhood streets.
"It's a good event for them," said county Councilwoman Cecilia M. Stepp, who represents the area. "They've tried to be sensitive to us. They were here long before we were, so we have to be sensitive to that, too."