It has been almost 15 years ago since I was there, but Ft. Riley used to do something like this in conjunction with their annual Apple Fest activities that were held on post. They had SAW's set up alongside vendor booths with family members, to include kids, suited up in Kevlar and eye protection shooting belted 7.62MM blanks as well as blue ball grenades being thrown at a target in a designated cordoned off spot. I honestly can't remember if the training grenades were fuzed or not but seems like they were. I'd suggest reaching out to the Safety Office at Ft. Riley and asking them for info on how they managed this event as it was huge. Several thousand people in attendance. From a surveillance perspective I'd certainly not be comfortable with recommending units using COTS ammo in military weapons for an event like this. I'd also recommend clarifying what you mean by training munitions. Blank, CCMCK, i.e., paint rounds, etc. or actual LIVE rounds coming from the units training allocation. Good luck! I'd hate to be the guy submitting the risk acceptance!