If you have a traverse that defines the breaklines you want to remove, you can remove them from a surface using that traverse. This works whether or not you added the breaklines to the surface via a traverse.
See Using Breaklines.
If you created feature lines like ‘edge of road’ and ‘ditch’ in a drawing and determine that these are also breaklines for the surface, you can import these traverses into a surface and TPC will generate the appropriate breakllines. See Get Breaklines From Traverse.
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