how do i blacklist oil rig monument

As the oil rig is out to sea there is may  001% chance of the event happening that far from land, on the other hand "blacklisting" does not seem to be working for a while, if you check posts on the help page  you will  notice that there has been no response to that misfortune,

i have set it to take place at monument only but it will start at rigs some times i see no point of it being there i wanted it on land only 

I've attempted to blacklist oil rigs. Hopefully the event will not spawn at monuments either. Please let me know here, or create another thread.