HAZARD MITIGATION



1.     HAZARD MITIGATION OPTIONS

1.1            Mitigation from Improper Design or Materials Selection

If failures, direct examinations, and/or risk assessments identify a high susceptibility to unacceptable design or materials, one or more of the following types of risk mitigation actions shall be initiated
  • In-line inspection of pipeline to determine nature and extent of design and material issues.
  • Pressure test of pipeline to identify weld or material flaws.

1.2            As-Built Flaws Mitigation

Design and manufacturing flaws, may be flaws in the fabrication of the steel itself, out of specification material properties, a flaw in the construction process or it may be a problem in the coating or cathodic protection system. The following types of risk mitigation actions should be initiated
  • Fabrication Specifications
  • Construction Specifications
  • Independent Verification
  • Independent Audit
  • Pressure Hydrotest

1.3            Internal Corrosion Mitigation

If failures, direct examinations, and/or risk assessments identify a high susceptibility to unacceptable internal corrosion rates, one or more of the following types of risk mitigation actions shall be initiated:
  • In-line inspection of pipeline to determine nature and extent of internal corrosion.
  • Review of existing pigging and chemical program selection and performance.
  • Assessment of alternative internal corrosion monitoring devices to better assess corrosion activity.
  • Feasibility study for changing operating conditions to reduce corrosion risk.

1.4            External Corrosion Mitigation

If failures, direct examinations, and/or risk assessments identify a high susceptibility to inadequate cathodic protection levels or unacceptable external corrosion rates, one or more of the following types of risk mitigation actions shall be initiated
  • ECDA studies of pipelines with suspected external coating degradation to determine cathodic protection (CP) effectiveness along the length of the pipeline.
  • In-line inspection of pipeline to determine nature and extent of external corrosion damage.
  •  Installation of additional test stations to measure the effectiveness of CP levels at locations where instant “OFF” readings cannot be measured.
  •  Alternative current interruption technology to better assess polarized CP levels.
  • Upgrading or installation of CP systems to allow for improved current distribution to the pipelines.

1.5            Third-Party Damage Mitigation

If failures, direct examinations, and/or risk assessments determine a high susceptibility to third party damage, one or more of the following types of risk mitigation actions shall be initiated
  •  Regular survey 
o   Increased frequency of ROW patrolling.
o   Improved signage and ROW visibility via brushing and clearing.
o   Enhanced communications with landowners to identify pipeline locations and to handle land usage issues.
  •  Public awareness
  • Depth of burial

1.6            Improper Operations Mitigation

If failures or risk assessments identify a high susceptibility to operations deficiencies, one or more of the following types of risk mitigation actions shall be initiated
  •  Review operator training and qualification programs.
  • Review standard operating procedures and Operations and Maintenance Manual.
  • Assess operating control equipment (SCADA, ESD) to improve process controls.
  • Robust operating procedures
  • Independent audit

1.7            Mitigation from External Forces

If routine ROW patrolling identifies any risks associated with ground movement, soil erosion, or river/creek bottom scouring, the following types of risk mitigation activities shall be initiated
  •  Depth of cover and elevation survey of the affected section of the pipeline.
  • Assessing underground movement using monitoring equipment, such as inclinometers or strain gauges. 
  •  Hydro technical and/or geotechnical engineering evaluations to determine remedial action options, which may include
o   Pipeline re-routing or replacement using horizontal directional drilling.
o   Line lowering within the existing right-of-way.
o   Armoring of approach slopes and banks to mitigate further damage.

1.8            Leak and Break Detection

Pipeline operating companies are required by CSA Z662 (Latest Edition) Clause 10.2.6 to make periodic pipeline balance measurements to check system integrity. Both installed devices and operational procedures must be in place to detect pipeline failures early.
Operations personnel must be diligent in the observation of pipeline and pipeline system components during field surveillance. Knowledge of normal operating conditions, such as system pressures, is integral to leak detection. Not all pipeline leaks are noticeable by operating conditions. Therefore, during daily rounds, the operator must observe line and lease conditions that may result in a failure.
Production volume discrepancies must be taken into account daily, since low production for no apparent reason may signify a pipeline leak or rupture.
In the event of a report of a problem or spill from the public or another outside party the operator must immediately investigate.
If a pipeline leak or rupture is detected, the source of the released product must be isolated immediately. If there are multiple possibilities, isolate all possible sources and determine the correct source after the release is under control.


HAZARD
DESCRIPTION
MITIGATION
Improper Design or Materials Selection
If failures, direct examinations, and/or risk assessments identify a high susceptibility to unacceptable design or materials, one or more of the following types of risk mitigation actions shall be initiated:
  • In-line inspection of pipeline to determine nature and extent of design and material issues.
  • Pressure test of pipeline to identify weld or material flaws.

As-Built Flaws

Design and Manufacturing flaws may be flaws in the fabrication of the steel itself, out of specification material properties, a flaw in the construction process or it may be a problem in the coating or CP system.
  • Fabrication Specifications
  • Construction Specifications
  • Independent Verification
  • Independent Audit
  • Pressure Hydrotest
Corrosion
Pipelines whether buried or above ground are exposed to both internal and external corrosive environments.
Internal
  • Process Control
  • Corrosion Inhibition
  • Regular Cleaning Pigging
External
  • Cathodic Protection
  • Coating
Third-Party Damage
The threat of 3rd party accidental or deliberate impact on the pipeline is an event-based scenario.
  • Regular survey
  • Public awareness
  • Depth of burial
Improper Operations
Operational misuse arises as a failure event through incorrect operating procedures or a failure to follow the correct procedure by company personnel.
  • Review operator training and qualification programs.
  • Review standard operating procedures and Pipeline Operations and Maintenance Manual.
  • Assess operating control equipment (SCADA, ESD) to improve process controls.
  • Robust operating procedures
  • Independent audit

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