Knoxville (WVLT) -- The Union County Sheriff's Department is investigating the discovery of an elderly Knoxville man's body, found inside a mine Monday.

Investigators say they don't suspect foul play.

Instead, they believe Charles Ried died as a result of what the Alzheimer's Association calls "wandering."

We're covering East Tennessee health, with details on wandering and who's at risk.

An estimated 22,000 older adults are living with Alzheimer's disease within the 26 county radius.

It is the most common type of dementia, accounting for 60 to 80 percent of cases.

Alzheimer's Association Eastern Tennessee Chapter Executive Director Janice Wade says, "But four out of every ten people with Alzheimer's will develop kind of a wandering characteristic, and that's very concerning."

Alzheimer's patients who are at risk:

Return from a regular walk or drive later than usual.

Tries to fulfill former obligations, such as going to work.

Tries or wants to "go home" when they are at home.

Is restless, paces or makes repetitive movements.

Has difficulty locating familiar places.

Checks the whereabouts of familiar people.

Acts as if doing a hobby or chore, but gets nothing done.

Appears lost in a new or changed environment.

Wade says, "We've had people you know be out of the state of Tennessee within a couple of hours because of the interstate and they can still drive."

Wade recommends the loved ones of dementia patients enroll them in safe return.

A program using ID products such as bracelets, clothing labels, wallet cards and key chains to locate missing people.

Wade says, "If a person is not returned to their home within about 12 hours, the chances of survival become less and less."

The Alzheimer's Association says people enrolled in safe return have a 99 percent return rate.

The Knox County Sheriff's Department also offers project lifesaver to dementia patients and their families.

Here, patients are assigned a radio frequency and can be located by wearing a bracelet containing a transmitter inside.

There is a small fee to enroll in safe return or project lifesaver, but financial assistance is available to those in need.

For more information, you can connect with the local chapter of the Alzheimer's Association by calling (865) 544-6288 or clicking the link below.