water jetting taking place.
c. Compaction of backfill placed by water jetting shall conform to the
requirements of this specification.
6. If the materials above the trench bottom are unsuitable for backfill, the
Contractor shall furnish and place backfill materials meeting the requirements
for trench backfill, as shown on the drawings or specified herein.
7. Should the Engineer order crushed stone for utility supports or for other
purposes, the Contractor shall furnish and install the crushed stone as directed.
8. In shoulders of streets and the road, the top 12-inch layer of trench backfill
shall consist of crushed gravel for sub-base, satisfying the requirements of
NHDOT.
C. BACKFILLING ADJACENT TO STRUCTURES:
1. The Contractor shall not place backfill against or on structures until they have
attained sufficient strength to support the loads to which they will be
subjected. Excavated material approved by the Engineer may be used in
backfilling around structures. Backfill material shall be thoroughly compacted
to meet the requirements of this specification.
2. Contractor shall use extra care when compacting adjacent to pipes and drainage
structures. Backfill and compaction shall proceed along sides of drainage
structures so that the difference in top of fill level on any side of the structure
shall not exceed two feet (2') at any stage of construction.
3. Where backfill is to be placed on only one side of a structural wall, only hand-
operated roller or plate compactors shall be used within a lateral distance of
five feet (5') of the wall for walls less than fifteen feet (15') high and within ten
feet (10') of the wall for walls more than fifteen feet (15') high.
3.04 DISPOSAL OF SURPLUS MATERIALS:
A. No excavated material shall be removed from the site of the work or disposed of by
the Contractor unless approved by the Engineer.
B. Surplus excavated materials, which are acceptable to the Engineer, shall be used to
backfill normal excavations in rock or to replace other materials unacceptable for
use as backfill.
C. Surplus excavated clean material not needed as specified above shall be hauled away
and disposed of by the Contractor at the Nashua Landfill. Arrangements must be
made with the landfill prior to delivery. Disposal of all rubble shall be in
accordance with all applicable local, state and federal regulations.
END OF SECTION
2019 CIPP Lining Project Earthwork
Nashua, NH 02300-8
