responsible for dewatering of each shaft. The shaft(s) shall be removed
and backfilled as soon as practical upon completion of the liner pipe and
the surface restored in accordance with the applicable provisions of these
specifications.
The Contractor shall minimize the time that a shaft remains open at a
particular site. Considerations shall be provided to complete and
coordinate all work including cleaning, pre-installation internal
inspection, pipe renewal, post-installation internal inspection and
acceptance so as to minimize disturbances. The Contractor shall
recognize that shafts shall not be removed/closed until the renewal pipe
has been internally inspected and accepted by the Engineer and it is
intended that each shaft shall be removed/closed and backfilled within
two calendar days from completion of the pipeline renewal work and
service reconnections.
3.3 INSTALLATION PROCEDURES
A.
Prior to pneumatically assisted sliplining pipe installation, the Contractor
shall insert a length of liner pipe test section to ensure that the existing
pipe is free of obstructions. The test section shall have an outside
diameter equal to or approximating the maximum allowable tolerance for
each reach and class of liner pipe and a length equal to that of the proposed
liner pipe for each reach of pipeline to be sliplined. The test section may
be left in place, provided it is not damaged and it meets design basis for
pipe reach. A new pipe section shall be provided at no additional cost, if
the Owner considers the test section damaged, worn, or not representative
of the actual liner pipe to be installed.
1. In the event the test section fails to pass through a reach, the
Contractor shall, at no additional cost to the Owner, use a shorter
test section(s) to determine if shorter lengths of liner pipe can be
successfully installed; provide for sliplining in the opposite
direction with a joint match at the point of obstruction; relocate an
access shaft or pit, with the approval of the Owner, to complete the
sliplining operation; and/or other means with prior approval by the
Owner.
2. Upon successful completion of the insertion of the test section, the
existing host pipe shall be considered ready to receive the liner
pipe and commencement of the pneumatically assisted sliplining
operation. The proposed liner pipe shall be lowered down into the
insertion pit and inserted into the existing host pipe. The
Contractor shall submit details for the pushing or pulling head to
be used, including the maximum allowable pushing or pulling
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