(Cleveland) - It's back to the salt mines for Cleveland Cargill workers.

Miners returned to work Thursday after a week-long shutdown due to a geological shift cin the salt mine that sits under Lake Erie.

“While we want to start out slow, we remain optimistic that we may be able to have everyone back by next week,” Mark Klein, director of communications, said in an email.

About 100 miners were put on paid leave when the mine closed August 19.

Klein told Newsradio WTAM 1100 that he tunnel affected was mined out several years ago. Cargill brought in additional equipment and engineering and geology consultants to determine the cause of the shift.

The movement in the mine is undetectable to the eye, but they still needed to find out a cause for the movement.  Klein says they continually measure the mines in 1/100 of an inch. The mine is 1,800 feet below lake erie, and about four miles offshore.

At that time, Klein told Fox 8 News the earth is always shifting to some degree, but even with a shift as small as 1/100th of an inch below Lake Erie, it could create a dangerous situation.

The salt mined 1,800 feet below Lake Erie and about four miles offshore is used on primarily for treating roads in the winter months.

(Photos by Carmen Angelo/WTAM 1100)

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