BURLINGTON TOWNSHIP, N.J. (CBS) — It was a surprise for school administrators as levels of mercury vapor in one Burlington Township elementary school actually went up after a rubberized floor was removed because of mercury concerns.

After it was found to contain potentially harmful mercury vapors, the rubberized gym floor at the B. Bernice Young School was removed this summer, but Burlington Township Schools Superintendent Mary Ann Bell says it became apparent that removal wasn’t enough.

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“What we found after that, was there was another layer of either adhesive or primer and the mercury levels in this lower layer was actually higher than the rubberized floor itself,” said Bell.

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So the district is now removing and re-pouring six inches of concrete under the floor. She says mercury vapor levels have remained within federal limits.

Bell says it’ll take three months for the new concrete to cure, and while the school will reopen on schedule Sept. 7, phys ed classes may be moved to other areas in the building.

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