McCook Quarry, which is owned by Hanson Material Services, has been in operation for 100 years. Blasting goes on every day and Tuesday was no different.
"A part of our blasting process which we are doing several times a week. We use seismic equipment and we stay well below regulatory limits," said Jeff Brasuell, Hanson area manager.
On Tuesday, a tremor was felt around 1 p.m. by residents around the town of McCook, as well as those in LaGrange. Initially, the U.S. Geological Survey called the activity an earthquake, but it backtracked after learning that there was a blast at a local quarry.
Hanson officials said the blast was well below the limits required by state law but, residents in nearby suburbs felt something huge. The United States Geological Survey, the federal agency that monitors earthquakes, says the tremor activity measured 2.7 on the Richter Scale. Initially the USGS called the event an earthquake. But now the agency is calling the event a possible quarry blast—with which Hanson strongly disagrees.
"We do not believe there is any correlation between mining activities and the seismic event the USGS reported," said Brasuell.
Despite that, Hanson did immediately call the state agency that regulates them to investigate and the Illinois Department of Natural Resources spent the day at the company looking at Hanson's blasting records. Until the situation is resolved blasting has been suspended.
Hanson, a second quarry and several surrounding suburbs are part of the Lyons Township Quarry Council, which has a hotline for community complaints. On Tuesday, more than 40 people called the hotline to report the tremors.
"We work closely with other businesses in the area and the Lyons Township Quarry Council to try work with the ...limit the affect on the community," said Brasuell.
Tuesday's tremor was picked up on the seismometer at Waubonsee Community College in Sugar Grove. An expert there said it was not earthquake.