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

About 45 miners returned to work Thursday after a week-long shutdown due to a geological shift in the salt mine that sits under Lake Erie.

"After completing a safety evaluation and installing additional monitoring equipment, we have decided to gradually resume work in the Cleveland salt mine," Mark Klein, director of communications, said in an email.

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

Klein says, “While we want to start out slow, we remain optimistic that we may be able to have everyone back by next week.” 

Over the last two weeks, Klein says gathered and analyzed a wealth of data. He says it has given them the confidence that the area of concern is isolated and that we can take measures to address the situation.  

Cargill continues to work closely with a number of third-party consultants, the Ohio Department of Natural Resources (ODNR) and the Mine Safety & Health Administration (MSHA).  

Klein told Newsradio WTAM 1100 last week that the 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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