(A) The subgrade is that earthwork overlaid by the base course. The fill or borrow used for subgrade material, as replacement for that removed as unsuitable by direction of the Board of Selectmen or its properly designated agent will be subject to the full approval of these town officials. It shall be deposited in layers not to exceed 12 inches in depth and rolled to compaction by a roller weighing not less than ten tons until each layer is thoroughly consolidated, for the entire area of construction.
(B) Where underground water is encountered at elevations of one foot and less below the bottom of the subgrade, excavation for the subgrade shall be carried to a depth not to exceed two feet below the finished grade as shown on the design profile for the road. The space so provided shall be backfilled with rock not over eight inches in diameter of coarse free draining soil meeting State Highway Department Specifications 1.06 of 809, Page 35.
(C) All underground drains as approved by the Board of Selectmen shall be installed and backfilled sufficiently to drain the highway effectively before placement of base course will be permitted.
(D) The finished grading of the subgrade shall have a cross section as outlined in § 98.001(B). It shall be 19 inches below finished grade for a minimum width of 34 feet for a width between curbs of 30 feet and 38 feet for a width between curbs of 24 feet and conform to the grades as shown on plans and profiles. Also, the crown of the subgrade shall correspond to the crown of the finished road. Town inspection shall be required during construction and when completed.
(Ord. passed 4-1-1968; Ord. passed 12-13-1976; Ord. passed 8-16-1982)