MITIGATION OF EXISTING FREE SPAN (APPROX. 37 MTR.) and REGULAR UNDER WATER SURVEY/ INSPECTION AT SUBSEA SECTION (6.4 KM) OF 26 inch URAN THAL PIPELINE (UTPL)

Amount

Free Span Survey: Survey of pipeline at the existing free span area for evaluating the extent & condition of the said free span after monsoon, using portable echo sounder and DGPS positioning control and supplemented by diver observation as per scope of work. Charges for diver will be considered included in this SOR

Tidal and current measurement at five locations near the subsea pipeline as per scope of work

Bathymetry survey along the pipeline section in subsea area 100 meters on each side as per scope of work including inspection of tidal zone & submission of report

Side Scan Sonar Survey & Sub Bottom Profiler survey together for the entire subsea pipeline section twice in a year once before monsoon and once after monsoon including submission of reports to identify free spans, if any exist, and the presence of debris along the pipeline as per scope of work.

Diving Survey: Carrying out underwater diving surveys deploying divers, diving equipment, etc., as per the specification and scope of work, processing of the data and submission of reports as per tender requirement on as & when requirement basis. This SOR is not applicable for any other mitigating activities/ surveys mentioned against any other SOR.

Cement & sand bags (1:3): Carrying out remedial works including supply & Installation of cement & sand bags (1:3) and placing of the same, if required, as per specification as per scope of work. Rate will be applicable both for under water and tidal zone. Charges for diver for mitigation action will be considered included in this SOR. Supply & installation of Concrete Mattress is not part of this SOR and will be certified against SOR-9, if used, separately.

PP Rope Gabion: Supply and installation of polypropylene rope gabions (9 mm PP Tarred rope, 100 mm mesh size, 4 strand) filled with Geo bag containing cement & sand mixture (1:3) as per scope of work. Rate will be applicable both for under water and tidal zone. Charges for diver, equipment, materials, safety arrangement as mentioned in the scope of work will be considered included in this SOR. Supply & installation of Concrete Mattress is not part of this SOR and will be certified against SOR-9, if used, separately.

Grout Bag: Supply & Installation of pipe supports of Fabric Formwork grout bag as mentioned in the scope of work along with scour prevention skirt grouted with anchor beam and stabilization mattresses (Restraint mattresses) for mitigation of existing free span & for any other mitigation which may be required during the contract period as may be decided by GAIL. Charges for all required resources including materials, consumables, safety gears, equipment, machineries, manpower, diver, are included & no separate payment other than this SOR shall be made to complete the job in all respect including submission of report. Concrete Mattress at the top/ bottom of the support/ pipeline shall be in scope of this SOR and no separate payment will be made.

Supply and installation of Concrete Mattress as per requirement for all the jobs other than SOR 8. Refer the scope of work & Annexure-IV

BLUEFIN MARINE