can i use correlation time to limit email actions on multiple events

I am using LEM in a process control environment. Firewall deny means something is wrong, so i have a simply set of alerts from each firewall to send an email on deny. We had a probelm with an application that was creating 6-10 deny / second, I end up with 17000 emails. 

Is there an easy way to add a delay, so i would get one email every ten minutes with deny , stop this problem happening agin ?