Special to Iredell Free News

RALEIGH – The N.C. Department of Environmental Quality (DEQ) is investigating a sinkhole collapse and release of sediment containing coal ash adjacent to Highway 150 in Mooresville.

DEQ was made aware of the collapse of a stream culvert pipe under a coal ash structural fill during heavy rains on Thursday, September 17, that caused a previously repaired sinkhole in a parking lot to reopen.

The parking lot is built on a documented coal ash structural fill, and DEQ has been monitoring the sinkhole since becoming aware of it during a site inspection in July of 2019. The property owner had previously repaired the sinkhole in 2018 and 2019.

During site visits after the storm, sediment containing coal ash was observed in the stream bed of the unnamed tributary where it emerges south of Highway 150. DEQ staff collected water quality samples from the stream and is conducting ongoing monitoring.

The location is in the area of a North Carolina Department of Transportation (NCDOT) expansion project, and DEQ has discussed necessary next steps with the property owner and NCDOT. DEQ also alerted county and state emergency management authorities.

DEQ will hold the responsible parties accountable for any violations that may have occurred and continue oversight of the remediation at the site.