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Flaws in OIL operational plan: NGT panel

By SIVASISH THAKUR

GUWAHATI, Aug 2 - The expert committee constituted by the National Green Tribunal to look into the Baghjan blowout has, in its preliminary report, cited shocking and wide-ranging lapses on the part of Oil India Limited (OIL) that range from compromising on fundamental safety aspects for gas condensate wells to glaring flaws in planning of critical operations.

According to the report, OIL had deficiency in the �understanding of the gravity of a critical operation like removal of BOP without having a confirmed and tested secondary safety�.

It has also suggested a number of immediate preventive measures for avoiding similar incidents of blowout and explosion.

The Assam Tribune had earlier reported how OIL made serious compromises on safety aspects of a gas well that require extraordinary precautionary measures in terms of servicing, work-over, safety measures and overall maintenance compared to an oil well.

Noting that handling of gas wells was different than oil wells, the committee in its report called for having a different standard operating process for gas wells.

�Isolation of any Hydrocarbon bearing Zone by a secondary barrier must be taken very seriously and needs to be planned properly. In such well situation, the safety barrier cannot be relied upon only on Hydrostatic Head of well Fluid. There ought to be proper secondary safety barrier, which are tested both positively and negatively to check its integrity before attending any critical operation in the well like nipple down of BOP,� it said.

The report said that before any critical operation in a well, a comprehensive contingency plan must be in place to take immediate action to face any eventuality. �In this particular well, due to not having any such plan, driller at site was confused what to do when he observed well activity,� it added.

The report noted �a clear mismatch between planning and its execution� at site and deviations from the Standard Operating Procedure (SOP).

Also, serious deficiencies of proper level of supervision of critical operation were there at well site � both from the contractor as well as from OIL.

�There was a flaw in the operational plan. The decision to place a cement plug at a depth of 1,000 metres in an inclined portion of the well (26 to 27 degree) as a secondary safety barrier itself was flawed. The cement plug should have been placed as near to the perforated zone and in this case near to the Packer, i.e., about 100 metres above Packer by placing a 100-metre sand plug above Packer to protect Packer from cement cutting failing during cement drilling,� it said.

OIL�s contention that setting Retrievable Bridge Plug (RBG) as a safety barrier in place of cement plug was not in practice in OIL, the committee found it �surprising�, saying that SLB logging contract with OIL was in place, and only a provision in the contract was needed to use RBP as and when required.

On fixation of responsibility for the accident, the committee stated that at present investigations were ongoing, and it would be able to give a clear finding on whom to fix responsibility for the accident in its subsequent reports.

The report said that placement of secondary safety barrier must be placed as near to the perforated zone, and cannot be placed anywhere in the well. �Placement of Cement Plug is to be always done in the vertical portion of Casing. If required to place Cement Plug in a deviated well, either a perforated Tubing/Drill pipe shoe is to be used and the string ought to be rotated during placement of cement slurry,� it said.

The committee also found that without the relevant supporting documents before the committee, OIL has flagrantly violated the procedure envisaged under Section 25 and 26 of the Water Act and Section 21 of the Air Act.

�It is pertinent to note here that the PCB, Assam has not placed any such document which indicates that the said letter dated 05.07.2006 was approved and that the relevant CTE/NOC and/or the CTE had been granted for the drilling Well Baghjan-5 in 2006. In fact, it can be safely concluded that OIL had never procured or any such CTE/NOC and/or CTO under the aforesaid Acts and Rules in the manner prescribed for drilling operation of Well Baghjan-5 in 2006,� it said.

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Flaws in OIL operational plan: NGT panel

GUWAHATI, Aug 2 - The expert committee constituted by the National Green Tribunal to look into the Baghjan blowout has, in its preliminary report, cited shocking and wide-ranging lapses on the part of Oil India Limited (OIL) that range from compromising on fundamental safety aspects for gas condensate wells to glaring flaws in planning of critical operations.

According to the report, OIL had deficiency in the �understanding of the gravity of a critical operation like removal of BOP without having a confirmed and tested secondary safety�.

It has also suggested a number of immediate preventive measures for avoiding similar incidents of blowout and explosion.

The Assam Tribune had earlier reported how OIL made serious compromises on safety aspects of a gas well that require extraordinary precautionary measures in terms of servicing, work-over, safety measures and overall maintenance compared to an oil well.

Noting that handling of gas wells was different than oil wells, the committee in its report called for having a different standard operating process for gas wells.

�Isolation of any Hydrocarbon bearing Zone by a secondary barrier must be taken very seriously and needs to be planned properly. In such well situation, the safety barrier cannot be relied upon only on Hydrostatic Head of well Fluid. There ought to be proper secondary safety barrier, which are tested both positively and negatively to check its integrity before attending any critical operation in the well like nipple down of BOP,� it said.

The report said that before any critical operation in a well, a comprehensive contingency plan must be in place to take immediate action to face any eventuality. �In this particular well, due to not having any such plan, driller at site was confused what to do when he observed well activity,� it added.

The report noted �a clear mismatch between planning and its execution� at site and deviations from the Standard Operating Procedure (SOP).

Also, serious deficiencies of proper level of supervision of critical operation were there at well site � both from the contractor as well as from OIL.

�There was a flaw in the operational plan. The decision to place a cement plug at a depth of 1,000 metres in an inclined portion of the well (26 to 27 degree) as a secondary safety barrier itself was flawed. The cement plug should have been placed as near to the perforated zone and in this case near to the Packer, i.e., about 100 metres above Packer by placing a 100-metre sand plug above Packer to protect Packer from cement cutting failing during cement drilling,� it said.

OIL�s contention that setting Retrievable Bridge Plug (RBG) as a safety barrier in place of cement plug was not in practice in OIL, the committee found it �surprising�, saying that SLB logging contract with OIL was in place, and only a provision in the contract was needed to use RBP as and when required.

On fixation of responsibility for the accident, the committee stated that at present investigations were ongoing, and it would be able to give a clear finding on whom to fix responsibility for the accident in its subsequent reports.

The report said that placement of secondary safety barrier must be placed as near to the perforated zone, and cannot be placed anywhere in the well. �Placement of Cement Plug is to be always done in the vertical portion of Casing. If required to place Cement Plug in a deviated well, either a perforated Tubing/Drill pipe shoe is to be used and the string ought to be rotated during placement of cement slurry,� it said.

The committee also found that without the relevant supporting documents before the committee, OIL has flagrantly violated the procedure envisaged under Section 25 and 26 of the Water Act and Section 21 of the Air Act.

�It is pertinent to note here that the PCB, Assam has not placed any such document which indicates that the said letter dated 05.07.2006 was approved and that the relevant CTE/NOC and/or the CTE had been granted for the drilling Well Baghjan-5 in 2006. In fact, it can be safely concluded that OIL had never procured or any such CTE/NOC and/or CTO under the aforesaid Acts and Rules in the manner prescribed for drilling operation of Well Baghjan-5 in 2006,� it said.

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