Go to the that area in Surveyor and look for a split in a spline joint. Click on the spline joint with the height adjustment tool, and this will fix the split.
@Stewart,
Floating track is a pain, and I hate it too. Use the terrain height adjustment tool along with the track terrain-leveling tool to fix this. I get the height of the track then go into the topology tool and set the land height to be the same and apply this to the area.
John