A.   Proper tools and equipment satisfactory to the Town shall be used for the safe and convenient progress of sewer installation. Whole pipe and fitting shall be carefully lowered into trench in such a manner as to prevent damage to pipe materials and protective coatings and linings.
   B.   Under no circumstances shall materials be dropped or dumped into the trench. Every precaution shall be taken to prevent foreign material from entering the pipe while it is being installed.
   C.   The pipe shall be clean and all sand, gravel, concrete and cement grout that has entered the lines in the process of construction shall be removed. (1993 Code § 12.08.070)