Columbia County officials believe a loud, window-rattling “boom” this morning in the Appling area was caused by blasting at a rock quarry on Columbia Road.
"(Martin Marietta quarry) just confirmed that they had a shot at 10:30 a.m.," county Emergency and Operations Director Pam Tucker said in an email.
Reports of the noise have come in from across the northern end of the county about the time of the reported blast.
Initially, officials thought the noise came from a sonic boom created by a military aircraft breaking the sound barrier.
Martin Marietta was expected to blast rock today, but not until noon, Tucker said.
Though some thought the boom might have come from an earthquake, Tucker said none have been detected by either the Savannah River Site Geotch Group or by the U.S. Geological Survey.
There have been widespread reports of a loud noise as far away as North Carolina. One person responding to a Facebook post reported hearing the noise in Wrens, Ga.
"Considering that they blast every couple of weeks and we never have this kind of response from people to (have) heard or felt it, it must have been a large one," Tucker said.
Later, Tucker said that "due to the placement of the blasting in the pit, the energy was expelled out from the shot, causing it to be heard for the distances reported."
Blasting is what Columbia Middle School secretary Wendy Prickett assumed she was hearing this morning. “It kind of shook our doors,” she said.
The school is located next to the Dogwood Quarry, so personnel at Columbia Middle are accustomed to hearing blasting. Typically, though, the blasts occur at the end of the work day, when the quarry usually dynamites rock for removal.
On Ray Owens Road, about 4 miles away, North Columbia Elementary secretary Nancy Kensinger said “at first we thought somebody was on the roof working,” and then teachers told them the boom shook their interactive boards in their classrooms.
“It kind of felt like a large gust of wind slamming into the side of our building,” said a Martinez Columbia firefighter at Fire Rescue Station 10 on Ray Owens Road.