This has been discussed many times already on the forum, and it's the same for all our sceneries.
The ground scenery IS made in tiles, and it's not possible to have a 100% perfect junction between them, there's nothing to fix, it's just a compromise that must be accepted to have a combination of good quality, native FSX materials, good fps, no blurries, all at the same time.
It's less visible the higher resolution the ground textures are, so perhaps here is a bit more visible than at JFK2 or KLAX, because there we used 4096x4096 ground textures, while here we used 2048x2048 textures, because the airport area is way larger and we don't want to risk OOMs.
In any case, you don't have any problems, is just how the scenery is made.