Seeking incident log for 68th Explosive Ordnance Detachment (EOD) in Ravenna, OH in 1973?

I was assigned to the 68th EOD in Ravenna Ohio in 1973 and I am looking for information concerning incident that I was involved in that year. How do I find the Incident log for that unit and that year?

Our unit was contacted by the Toledo Ohio Police department concerning a box full of dynamite sitting in the back of an van in an automotive salvage yard. My commanding Office and I responded to the request and found over 20 sticks of dynamite  deteriorating in a box. We had to remove each stick one at a time to record serial number information, I had removed about half of the sticks when I found 5 or 6 blasting caps laying in nitroglycerin on the bottom of the box (the box was a dynamite box that was wax lined) and the temperature on that day was close 100 degrees.

We had to move the dynamite to an open field  to dispose of it. I need to find out an approximate date that this incident happened. Any suggestions on how I can find this information?