Not off-topic at all and the answer to your question is in the OP.
RTFM. What a concept .
I deliberately only wrote how to get rid of the ground explosions instead of uploading such a mod aswell, because i was very afraid that people would download that mod without thinking and would then complain about the ground explosions being gone aswell, even though they wanted to make the ambient flak disappear only.
BTW, i can understand why they added this ambient flak in the first place. Nothing wrong with that. However, i would've preferred to have the option to not see it. Especially when it's such an easy fix. I was actually hoping that they would use this mod (which just delets some lines a text file basically) and turn it into a setting in RoF. Unfortunately, they haven't done so yet.