Drilling will determine extent of mines under Swansea school

School leaders are trying to plan for the future in a district that evacuated one of its schools because it was damaged by mine subsidence.

The subsidence issues progressed quickly at Wolf Branch Middle School. Students and staff moved out of the 15-year-old building days after school officials called the Illinois Department of Natural Resources to begin monitoring ground movement there.

IDNR engineers now have plans to drill into the ground as part of their investigation.

The engineers have historical maps of the abandoned mine under the school, which is causing the subsidence, or gradual sinking. But they want to do some “exploratory drilling” to confirm the “location and extent of the mine workings,” according to an IDNR spokesperson.

The spokesperson said the information will help IDNR and the district make decisions about the future of the school.

Superintendent Scott Harres said Wolf Branch District 113 has had meetings with IDNR and with the Illinois State Board of Education about moving forward.

Movement is still being detected but at a slower pace than when engineers first got to Swansea in September, according to Harres.

“It was averaging over an inch a day. Now, it’s down to a just over a millimeter a day on average,” Harres said. “They’re optimistic that it will continue to slow down.”

The drilling is expected to begin later in October or early next month. Engineers hope to complete the work in November.

The middle school officially closed on Sept. 18, when middle school students started taking classes at Wolf Branch Elementary School, less than a mile away.

Harres said previously that no movement has been detected at the elementary school building. It’s crowded there now with the added students, but Harres said the building has held more children in the past when enrollment was higher.

“At the elementary school, the teachers and the students continue to make it work,” he said. “... It’s very compacted, but things are getting done.”

This story was originally published October 6, 2017 at 9:28 AM with the headline "Drilling will determine extent of mines under Swansea school."