Arkansas State Park Eerie Mechanical Cyclic Sounds – Video and Audio

In the past few days I have been to Murfreesboro Crater of Diamonds State Park, which is a dry field in an ancient volcanic caldera and at Winona Lake Park. Both sites have had the exact same frequency cycling at high decibel to the point of annoyance. It’s faintly audible on the video but extremely loud in person. Have you experienced this at a state park recently or maybe elsewhere in the country? Neither facility had an explanation.