(CNN)Uranium ore stored at the Grand Canyon National Park museum may have exposed visitors and workers to elevated levels of radiation, according to the park's safety, health and wellness manager.
For nearly 2 decades, Grand Canyon tourists were exposed to radiation beyond the federal limit, safety manager says
Elston Stephenson told CNN that he began asking officials from the National Park Service and Department of the Interior last summer to warn workers and tourists they had possibly been exposed to unsafe levels of radiation. After his requests were ignored, he said he sent an email to all park staff at the Grand Canyon on February 4.
"If you were in the Museum Collections Building (bldg 2C) between the year 2000 and June 18, 2018, you were 'exposed' to uranium by OSHA's definition," said the email, which Stephenson provided to CNN.
"Please understand, this doesn't mean that you're somehow contaminated, or that you are going to have health issues. It merely means essentially that there was uranium on the site and you were in its presence. ... And by law we are supposed to tell you."
The National Park Service is investigating what happened and working with the Occupational Safety and Health Administration and the Arizona Department of Health Services, according to the Department of the Interior, which oversees the park service.
"Uranium naturally occurs in the rocks of Grand Canyon National Park. A recent survey of the Grand Canyon National Park's museum collection facility found radiation levels at 'background' levels -- the amount always present in the environment -- and below levels of concern for public health and safety. There is no current risk to the public or Park employees," the department said in a statement provided to CNN.
The National Park Service also said there is "no current risk" to the public or park employees.
"The museum collection facility is open and employee work routines have continued as normal," Emily Davis, spokeswoman for the Grand Canyon National Park, said in a statement. "The NPS takes public and employee safety and the response to allegations seriously. We will share additional information about this matter as the investigation continues."
Stephenson told CNN that in early June he found out about three 5-gallon buckets of uranium ore that had been stored next to a taxidermy exhibit at the park's museum for nearly two decades. He said he immediately contacted a park service radiation specialist to report the danger.
According to a report from a park service radiation safety officer who responded to Stephenson's request on June 14, 2018, testing results were positive for radioactivity above background levels near the buckets, but elsewhere the radiation levels were not elevated.
Still, according to the report, the park service decided to remove the buckets on June 18 and dispose of the contents in the nearby Lost Orphan uranium mine, where the ore had come from.