GASTONIA, N.C. – Crews are once again cleaning classrooms at Forestview High School after stains were discovered on the building’s tile floors.

It’s prompted concerns on social media from parents after topical mold was discovered on school furniture back in August.

Gaston County Schools spokesperson Todd Hagans said the school sits on a natural spring, and as a result, moisture from the drainage system underneath the building interacted with the glue in the school’s tile floors, producing the stains.

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Hagans said the county hired an environmental engineering firm which determined no topical mold is present in the building and that the facility’s air quality is good.

He said cleaning crews have been hired to strip the floors and clean them.

“We have moved several classrooms so that work can get underway,” Hagans said. “But we feel we have a safe environment.”

Hagans said crews worked both last weekend and this coming weekend with the cleaning scheduled to be finished by Monday.