LOUISVILLE, Ky. (WDRB) -- The health department is taking a serious look at the air in northeastern Jefferson County as a brush fire continues to burn.

"We figure this is going to last throughout the rest of the week. This is not something you can just throw a bunch of water on," said Middletown Fire Chief Jeff Riddle.

Smokes continues to fill the area surrounding Jefferson County Stone on Old Henry Road. Officials from Middletown Fire say flames broke out in a composting and mulching area.

The fire department says it's more of a nuisance than a health hazard. About 25 to 30 businesses have been affected.

"We've been in contact with each of these businesses, so that we can advise them on shutting down some of their air handlers and some of their air intake areas, so that they're not bringing smoke into their buildings," Riddle said.

The cause of the fire is still under investigation, however the fire department suspects spontaneous combustion.

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