SCOPE
This
specification covers contractor's supply of all labour, materials,
transportation, equipment and other services necessary for dredging, including
disposal of all dredged material.
WORK
INCLUDED
Conducting
the survey and sounding work.
Dredging
all any kind of materials, below water level as shown on the drawings.
Providing
the disposal area of dredged material.
Obtaining
all necessary permits from the appropriate regulatory government agencies for
dredging and disposal of the dredged spoil materials.
WORK
NOT INCLUDED
Excavation
and fill work
QUALITY ASSURANCE/QUALITY CONTROL (QA/QC)
Contractor
shall fully comply with the Project Quality Assurance/Quality Control
Requirements. For submitting Quality
Assurance/Quality Control Procedures and Documentation the provision of clause
“Submittals” of these specifications shall apply.
SUBMITTALS
Contractor shall furnish with his bid
proposal the capacities, specifications and description of the method he
proposes to use for dredging of different materials for Owner's review.
Before
commencement of the work, the Contractor shall submit for approval of the Owner
a statement described the plant in detail which he proposes to use for dredging
and disposal of dredged materials and evidence to demonstrate that the plant
has adequate capacity to complete the work in time.
The
quality control procedure shall include but not be limited to the following:
- Survey procedure
- Dredging operation procedure
- Inspection procedure
DREDGING EQUIPMENT
If any intent of the Owner to use all
dredged material as backfilled material, the dredging equipment used for the
work shall be suitable for recovering the excavated materials for stockpiling
and later use.
The
dredging of the work shall be performed by appropriate plant and
equipment. The dredging equipment used
shall have the capability to dredge to depth greater than shown on the
drawings.
The
capacities of the equipment to be used should be adequate for completing the
dredging and disposal operation.
DREDGING
GENERAL
Contractor
shall obtain necessary permits from the appropriate regulatory agencies for the
dredging and disposal of the dredged spoil materials.
In
the event the Contractor's plant is sunk, The Contractor shall forthwith raise
or remove any plant at his own cost floating or otherwise belonging to him or
any Subcontractor or to any person employed by him (including also any plant
which is held by the Contractor or his Subcontractor under agreement for hire
or hire purchase) which may be sunk within the limits of the site in the course
of construction period or maintenance of the works or otherwise deal with the
same as the Owner may direct.
Until
the plant be raised or removed, the Contractor shall set buoys and display at
night such fights and do all such things for the safety of the navigation as
may be required by the Owner or any other authority having jurisdiction in
connection with the site. In the event
of the Contractor not carrying out the obligations imposed upon him by this
clause, the Owner may buoy and fight such sunken plant and raise and remove the
same (without any prejudice to the right to the Owner to hold the Contractor
liable) and the Contractor shall refund to the Owner all costs incurred in connection
therewith.
In
the event any such plant being sunk outside the limits of the site the
Contractor shall be subject to the powers of any authority having jurisdiction
in respect thereto and shall be liable to pay all costs and expenses incurred
with respect to buoying, fighting, raising and removal of such sunken plants,
and claims arising as the consequence of the sinking of such equipment.
The
Contractor shall take all reasonable measures to reduce the dispersal of the
dredged materials during dredging operation.
The
sequence of dredging shall be as indicated on the drawings or as directed by
the Owner
Monitoring
and control of the location shall be performed by the Contractor with an echo
sounder depth meter, respectively.
OPERATION
Before
the commencement of dredging and reclamation, the whole area to be dredged and
reclaimed, together with any adjacent areas whose levels might be affected by
the dredging and reclamation, is to be surveyed and sounded and plans and
sections are to be drawn accordingly.
The
survey work shall be done by the Contractor in the presence of the Owner in
accordance with the detailed directions and requirements of the Owner.
The
plans and sections shall, when finally and mutually agreed, be signed by the
Owner and the Contractor as truly representing the configuration of the area at
the commencement of dredging.
Contractor
shall furnish, establish and maintain in good order range marks, stakes,
gauges, sounding equipment, boats and buoys required for the proper execution
of dredging.
The
Contractor shall execute the dredging within the plan indicated on the drawing
or as directed by the Owner, and ensure that no portion of the finished dredged
work shall, at the time of acceptance be higher than the level or levels shown
on the drawings or as directed by the Owner.
The
tolerance allowable for the depth and side slopes for dredging is + 300
mm.
The
Owner reserves the right to order levels and soundings to be taken any time as
necessary for the proper supervision and measurements of the Work.
The
limits, levels, soundings etc., of the area to be dredged shown on the drawings
are for the purpose of guidance and assistance in estimating and no guarantee
is given for their accuracy.
Before the
Owner accepts that dredging works have been completed, the Contractor shall
demonstrate by means of sounding, surveys and sweeping, that the works have
been executed to the required lines, levels and slopes.
Such
soundings, surveys and sweeps shall be carried out in the presence of the
Owner.
Where
areas are shown not to have been dredged to the required lines, levels and
slopes, the Contractor shall return and remove all high spots or trim slopes to
the satisfaction of the Owner.
At
the conclusion of dredging, final surveys, levels, soundings, sweeps, plans and
sections shall be made and the appropriate plans and sections shall after due
agreement and signatures by the Owner and the Contractor, be deemed to
represent the final configuration of the dredging for the specified area.
DEPTH
AND BOUNDARY LIMIT FOR DREDGING
The
depth of dredging shall be as specified on the drawings.
Attention
shall be taken by the contractor any owner's installation or structure's
location, and the contractor shall be responsible to protect them for the dredging.
DISPOSAL OF DREDGED MATERIALS
If dredged materials required by the
owner, the materials shall be stockpiled at the designated area as fill
materials by the Contractor. The dredged
materials found suitable for fill as determined by the Owner may be directly
placed in the fill area or may be stockpiled for future use.
Pipelines
for the disposal of spoil shall be along a corridor approved by the Owner.
INSPECTION
The Contractor shall be responsible for
all inspection required by this specification.
The
Owner may, during the course of work observe the various phase of the Work
performed by contractor at the site.