Stanton, MO  (KTRS)  One of Missouri’s most popular tourist attractions is scheduled to reopen after being closed for about three months because of potentially harmful vapors.

The Environmental Protection Agency announced Thursday that Meramec Caverns in Franklin County will reopen Friday. The caverns were closed in April after tests found high levels of trichloroethylene, or TCE, vapors in the caves. TCE is considered a possible carcinogen.

Meramec Caverns laid off about half of its 100 employees after the closure,M but is in the process of hiring many of them back.