00:53 Grand Canyon Tourists May Have Been Exposed to Radiation Grand Canyon employees and tourists may have been exposed to dangerous levels of radiation as they passed by three buckets filled with uranium ore in the park’s museum collection building, according to the park’s safety manager Elston Stephenson.

At a Glance Three 5-gallon drums filled with uranium ore were stored near a taxidermy exhibit at the Grand Canyon Museum Collection building.

The drums were removed from the building last month, but the building remains open to the public.

The park's safety manager brought the incident to the public via an email sent to colleagues.

For nearly two decades, visitors and employees at a Grand Canyon museum may have been exposed to dangerous levels of radiation, a safety manager at the National Park says.

The source of the radiation is three 5-gallon drums filled with uranium ore stored near a taxidermy exhibit at the Grand Canyon Museum Collection building. The drums were removed from the building last month and their contents allegedly dumped into Orphan Mine, a nearby former uranium mine , but the building remains open to the public, according to a report by the Arizona Republic.

The public was not made aware of the drums or the alleged exposure to radiation until Elston Stephenson, the park’s safety, health and wellness manager, emailed his colleagues to warn them of the incident and tell them that nothing was done to warn employees or the public.

“If you were in the Museum Collections Building (2C) between the year 2000 and June 18, 2018, you were ‘exposed’ to uranium by OSHA’s definition,” Stephenson’s email read. "The radiation readings, at first blush, exceeds (sic) the Nuclear Regulatory Commission's safe limits. … Identifying who was exposed, and your exposure level, gets tricky and is our next important task."

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Stephenson said he emailed Acting Interior Secretary David Bernhardt and Deputy Inspector General Mary Kendall, urging them to warn the public, but nothing was done.

"Respectfully, it was not only immoral not to let our people know," he added in his email, "but I could no longer risk my (health and safety) certification by letting this go any longer."

Stephenson noted that one of the containers was so full, the lid would not close. He added that children who sometimes sat at the exhibit for 30 minutes at a time could have received radiation exceeding federal safety standards within three seconds, and adults, in less than 30 seconds.

The Park Service has launched an investigation, along with the Occupational Safety and Health Administration and the Arizona Department of Health Services, Emily Davis, a public affairs specialist at the Grand Canyon, told the Arizona Republic.