DHEC answers: Is mining causing the recent earthquakes?

COLUMBIA, S.C. (WIS) - Recent earthquakes in the Midlands have left residents asking questions about what’s happening. In response to the recent earthquakes the South Carolina Department of Health and Environmental Control (DHEC) provided some answers.

The organization said Thursday morning it was answering questions about whether mining activity in the Elgin area could be the cause of over 30 earthquakes in the last year.

DHEC said, “Currently, DHEC-permitted mine sites in the area are surface pits, and the majority are 30 ft. or less in depth. Their shallowness would not be expected to contribute to seismic activity, especially with recent earthquakes being recorded at 6,336 to 12,672 ft. deep...”

RELATED COVERAGE

DHEC also pointed curious community members to look at the state’s geological history. SC is the most seismically active state on the east coast.

The South Carolina Emergency Management Division (SCEMD) South Carolina Earthquake Guide says most of the state’s earthquakes occur near the coasts near faults.

SCEMD’s guide says, “Currently, there is no reliable method for predicting the time, place, and size of an earthquake.” However, it does say that, “where earthquakes have occurred before, they can again.”

The largest earthquake in SC history happened in 1886 in Charleston.

The 1886 earthquake rocked the Summerville/Charleston Area on Aug. 31, 1886. It was the largest earthquake to ever be recorded in the southeastern U.S. It killed 60 people and had a magnitude of 7.3. It lasted over a minute and was felt as far away as Alabama, Ohio and Kentucky and even in Cuba.

SCEMD’s guide says that if an earthquake of similar scale were to happen today in Charleston it would have devastating consequences. The department estimates as many as 9,000 people could be hospitalized and potentially 1,000 people killed.

Up to 200,000 South Carolinians could be displaced from their homes with up to $20 billion in damage. An earthquake of that scale could damage up to 800 bridges and leave up to 300,000 households without power. SCEMD estimates damage to water infrastructure could take weeks or months to fix.

SCEMD’s guide also advises to have a plan in the event of an emergency, especially for individuals with additional needs:

Talk to neighbors, family or caregivers beforehand
Have a supply kit ready in advance
Drop, Cover and Hold On during an earthquake

We have embedded the full guide below.

Sc Earthquake Guide by Nevin Smith on Scribd

Currently, DHEC-permitted mine sites in the area are surface pits, and the majority are 30 ft. or less in depth. Their shallowness would not be expected to contribute to seismic activity, especially with recent earthquakes being recorded at 6,336 to 12,672 ft. deep, per @USGS.
— SCDHEC (@scdhec) June 30, 2022