FormID: 0004d72e
Mesh: Architecture\WhiteRun\WRTerrain\WRBanneredMareBase01.nif
Screenshots:
https://imgur.com/a/uW9D0
This was originally reported in a placed ref ticket (
Issue #23241). I was able to confirm the problem. The particular mesh is very large, but Arthmoor said that we have done fixes for other "megameshes" like it in the past.
The screenshots I linked should give you an idea of where the gap is located. It is very tiny but noticeable if you look close enough.