Updated June 9 at 6:30 p.m. - Meramec Caverns will re-open Friday morning, months after it stopped cave tours because federal regulators measured high levels of a toxic chemical known as trichloroethylene, or TCE.

The popular tourist attraction in Franklin County installed air-lock doors and ventilation, and on Thursday, the U.S. Environmental Protection Agency said tours in "the upper levels of the caverns" could resume.

"We're just very happy that we're going to be able to open the tours," said gift shop manager Judy Turilli. "A lot of people have been disappointed who have come down that we weren't open. We're in the business of making people happy, so we're happy we're going to be able to do that."

Turilli said business took a hit during the closure and many workers had been put "on leave," but the site is "calling everybody back." She said she hopes the tourists return and business goes back to usual.

"It is supposed to be really hot this weekend," she said, "so this is a great place to visit."

Our original story, May 1, 2016 - The owners of Meramec Caverns say they hope to re-open by Memorial Day, in time for the busiest tourism months of the year.

The caves were closed to the public on March 10 after federal regulators measured unsafe levels of an industrial solvent called trichloroethylene, or TCE, in the caves and attached restaurant and gift shop. Workers are installing ventilation shafts and air scrubbers to keep the vapors out of the areas used by tourists, but the popular site has taken a serious financial hit in the process.

“We had maybe an hour to notify employees that we were laying them off. And some of them had been with us for 35 years,” said the site’s director of operations, Lester Turilli Jr.

The privately-owned caves have been in his family for four generations, he said, and the past months have been painful. Half of the tourist site’s permanent staff were laid off — about 25 people. Turilli said he has also delayed hiring about 50 seasonal workers. Most years, about 300 visitors pass through the caves each day in April, and up to 1,000 in the high summer.

“Not only does it hurt us, it hurts the businesses around us. It kind of sucks the life out of the whole area here in Franklin County,” Turilli said. He is also running for governor of Missouri as an independent candidate.

Prolonged exposure to elevated levels of TCE has been linked to some cancers, according to the Agency for Toxic Substances & Disease Registry. Regulators have measured TCE at the site for years and believe the vapor has leached in through groundwater, contaminated by a landfill and old factory site in Sullivan.

Letters to Turilli from the Environmental Protection Agency say workers should be notified of the potential health risks of inhaling air with elevated levels of TCE over a long period of time, and that female workers of childbearing age should not be exposed. But Turilli said he hasn’t heard concerns from his employees, because the levels are still far below limits kept by the Occupational Safety and Health Administration.

TRW Automotive U.S., LLC, which owns the former factory site in Sullivan where the TCE likely originated, has been tasked with cleanup at the Meramec Caverns as well. Angela Brees of the Environmental Protection Agency’s Region VII says workers are installing air-lock doors, ventilation and other measures to reduce the concentration of TCE in the air before the caves can re-open.

“At this point the airlock doors are nearly completed. We’re still evaluating separating the HVAC system in the cafeteria and gift shop, however we have installed air scrubbers in that space to keep the levels below health concern,” Brees said.

A ventilation shaft is being drilled, Brees said, but it’s yet unclear if a second will be needed.

In the meantime, activities like camping, canoeing and zip-lining are still up and running at the site just off of Interstate 44, Turilli said.

“We are doing our best to get the cave up and operational as soon as we can,” he said.

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