Easement Terminations

Working with easements that are worded something similar to "A 10' wide easement centered on the centerline of the storm sewer between Catch Basin A and Catch Basin B".  How would you terminate the easement?  Attached is a PDF with the easement terminating at the center of the catch basins in Option A and with the easement extending 5' beyond the catch basins in Option B.  

Option B in my opinion will allow the contractor to excavate around the catch basin where as Option A will not.

Any input will be appreciated.