Compliance Verification Activity Report: CV1819-542 - Westcoast Energy Inc., carrying on business as Spectra Energy Transmission

Overview

Compliance verification activity type: Field Inspection

Team:

• Inspector 2523
• Inspector 2589

Regulated company: Westcoast Energy Inc., carrying on business as Spectra Energy Transmission

Operating company: Westcoast Energy Inc., carrying on business as Spectra Energy Transmission

Province(s) / Territory(s):

• British Columbia

Discipline(s):

• Integrity Management

Related events:

• INC2018-142

Rationale and scope:

Pipeline integrity dig inspection: to inspect Enbridge/Westcoast’s integrity investigation and mitigation activities. These activities were scheduled on both the 9L1 (NPS 30 Mainline) and 9L2 (NPS 36 Mainline) pipeline sections to confirm their fitness-for-service following incident INC2018-142, which involved the rupture of the NPS 36 Mainline Transmission South (T-South) on 9 October 2018 near Prince George, BC.

Compliance tool(s) used:

• Information Request (IR) (1)

Facility details

Facilities:

• SPECTRA - 36" LOOP
• SPECTRA - 30" MAINLINE

Facility Types

• Pipeline
• Pipeline

Life-cycle Phases

• Operations

Regulatory requirements

Regulatory requirements that apply to this activity:

• National Energy Board Act (NEBA)
• Onshore Pipeline Regulations (OPR)
• National Energy Board Act (NEBA) 2016-06-19
• Standards
• CSA Z662-15 - Oil and Gas Pipeline Systems

Observations (no outstanding follow-up required)

Observation 1 - Observations - General

Date & time of visit: 2018-11-14 10:35

Discipline: Integrity Management

Categories:

• Pipeline
• Excavations
• Pipe Condition
• Repairs
• Integrity Management Program
• Hazard Identification
• Implementation

Facility:

• SPECTRA - 36" LOOP (Pipeline)

Observations:

The 9L1 and 9L2 pipeline sections are parallel. Their pipe specifications are:
 
9L1 Segment: The pipeline section was constructed in 1957 by Manning Construction, Maximum Operating Pressure (MOP) of 780 psi (5380 kPa) [6453 kPa for the rest of Mainline NPS 30 T-South], Grade X52 (359 Mpa), Nominal Wall Thickness (WT) 9.53 mm, DSAW (Manufactured by Consolidated Wester) and asphalt coated (girth welds are Polyethylene Tape coated).
 
9L2 Segment: The pipeline section was constructed in 1971 by Manning Construction, Maximum Operating Pressure (MOP) of 780 psi (5380 kPa) [6453 kPa for the rest of Mainline NPS 36 T-South], Grade X60 (414 MPa), Nominal WT 9.90 mm, DSAW (Manufactured by HME) and Polyken Tape coated (pipe body and girth weld).
 

Compliance tool used: No compliance tool used

Observation 2 - Observations of Integrity Dig Site # 9L2 - GW 18180

Date & time of visit: 2018-11-14 11:45

Discipline: Integrity Management

Categories:

• Pipeline
• Excavations
• Pipe Condition
• Repairs
• Integrity Management Program
• Hazard Identification
• Implementation

Facility:

• SPECTRA - 36" LOOP (Pipeline)

Observations:

Enbridge representatives stated that this site was selected for excavation based on an assessment model that Enbridge ran taking into account that the adjacent 9L1 pipe segment had some Stress Corrosion Cracking (SCC). As a result, the company wanted to verify the existence of SCC on the 9L2 pipe segment as well.
 
At the time of the inspection the assessment, including Non-Destructive Testing (NDT), was completed, the pipe recoated with liquid epoxy SPC 2888, and the excavation backfilled.
 
NEB inspectors requested that Westcoast provide additional information that was not available on site: see the details in the Information Request below.

Compliance tool used: No compliance tool used

Observation 3 - Observations of Integrity Dig Site # 9L1 - GW 2870

Date & time of visit: 2018-11-15 07:00

Discipline: Integrity Management

Categories:

• Pipeline
• Excavations
• Pipe Condition
• Repairs
• Integrity Management Program
• Hazard Identification
• Implementation

Facility:

• SPECTRA - 30" MAINLINE (Pipeline)

Observations:

• This site was selected for excavation based on a 2015 seam weld anomaly (feature # 004-000779) reported by a 2015 Electromagnetic Acoustic Transducer  (EMAT) in-line inspection (ILI) completed by General Electric (GE). The anomaly was confirmed in the field. Westcoast’s representatives stated that no other defects were identified by NDT. In addition, Westcoast’s engineering assessment concluded that the weld anomaly is not a defect and does not need further repair.
• At the inspection the exposed portion of the pipeline was recoated with liquid epoxy. STOPAQ coating was applied at both ends to ensure adequate transition with the original asphalt coating.

Compliance tool used: No compliance tool used

Observation 4 - Observations of Integrity Dig Site # 9L2 - GW 20290

Date & time of visit: 2018-11-15 12:30

Discipline: Integrity Management

Categories:

• Pipeline
• Excavations
• Pipe Condition
• Repairs
• Integrity Management Program
• Hazard Identification
• Implementation

Facility:

• SPECTRA - 36" LOOP (Pipeline)

Observations:

• This site was selected for excavation based on two seam weld crack anomalies, features # 020-006671 and 020-005222, reported by a 2015 EMAT ILI completed by GE. Westcoast had exposed and sandblasted the entire joints GW 20280 and GW 20290 of 12 m each. The EMAT feature 020-005222 was correlated with field measured feature TOE-AA-08 and the EMAT feature 020-006671 with field measured feature TOE-AA-02.
• ACUREN level II and level III NDT technicians were conducting Magnetic Particle Inspection, Manual ultrasonic testing (UT) and grinding.
• A number of shallow corrosion features were observed, assessed and grinded/buffed as required.
• There were SCCs on the pipe body and along the seam welds. Buffing of SCC and corrosion features along seam weld toe cracks was required to improve sizing accuracy.
• The NDT technicians confirmed that Radiographic testing was completed at all GW and seam weld locations where the grinding was expected to be deeper than 10 % WT, to identify any through wall leaking weld anomalies (from potential coincidental cracks, laminations, weld anomalies or internal imperfections) prior to grinding.
• UT Shear Wave at 60 and 70 degree measurements identified some laminations or inclusions of the pipe wall thickness from the surface to up to 3 mm deep along certain seam weld toe cracks.
• For a safe operation and excavation Westcoast implemented the following pressures to the 9L2 segment:
  • 100% of licensed MOP: 5379 kPa (780 psi)
  • 100% of last 60 days high: 5261 kPa (763 psi)
  • 80% of last 60 days high: 4206 kPa (610 psi) (imposed by an NEB Inspection Officer Order at the time of the inspection). However, the actual pressure was between 540 and 560 psi
  • 70% of last 60 days high: 3682 kPa (534 psi) (that will be applied for any grinding beyond 30% of pipe WT). However, the actual pressure was set at 502 psi (corresponding to 38.58 % of the pipe specific minimum yield stress) during grinding activities.
• Field measurements confirmed both EMAT reported weld anomalies. Also, other crack anomalies (not reported by EMAT) were identified. However, based on pipe actual wall thicknesses measured along crack locations and reported by ACUREN, the crack anomalies that were found outside of the two EMAT tool call-boxes did not meet the tool reporting threshold.
• The EMAT vendor provided the tool’s specifications, including 90% Probability Of Detection stated at a 95% confidence level for target features in plate material and in longitudinal weld areas with dimensions greater than or equal to 2mm depth and 50 mm length.
• Two clocksprings were installed at this dig site.
• Repaired portion were planned to be recoated with liquid epoxy SPC 2888.

Compliance tool used: No compliance tool used

Observation 5 - Information Request

Date & time of visit: 2018-11-16 18:34

Discipline: Integrity Management

Categories:

• Pipeline
• Excavations
• Inspections
• Repairs
• Integrity Management Program
• Hazard Identification
• Implementation

Facility:

• SPECTRA - 36" LOOP (Pipeline)

Observations:

During the inspection, NEB inspectors requested  information related to the assessment and repair activities that were being conducted in the field. Westcoast representatives stated that the information was partially incomplete (e.g. transitory documents to be finalized by NDT contractors, etc.) and partially unavailable on site. NEB inspectors requested that Westcoast provide the remaining information as an action item.
 

Compliance tool used: Information Request (IR)

Regulatory requirement:

• Onshore Pipeline Regulations (OPR)

Relevant section(s):

• • 4. General
    • (1) When a company designs, constructs, operates or abandons a pipeline, or contracts for the provision of those services, the company shall ensure that the pipeline is designed, constructed, operated or abandoned in accordance with the applicable provisions of
      • (a) these Regulations;
      • (d) CSA Z662, if the pipeline transports liquid or gaseous hydrocarbons; and
  • 40. A company shall develop, implement and maintain an integrity management program that anticipates, prevents, manages and mitigates conditions that could adversely affect safety or the environment during the design, construction, operation, maintenance or abandonment of a pipeline.

Company action required:

As per the inspection closing meeting, please find below the list of additional information to be filed as action items:
 

1.    Enbridge Standard Operating Procedure (SOP) for pipe crack (SCC, crack-like, seam and girth weld (GW) toe cracks) assessment (including determination of dimensions) and repair.
 
2.    Enbridge SOP for corrosion (metal loss) assessment (including determination of dimensions) and repair.
 
3.    For the digs in 9L1 and 9L2 area:
a)  A summary of ILI reported features/anomalies (where applicable);

b)  Updated field Non-Destructive Examination (NDE) assessment result:
        i.   Type(s) of NDE completed and their summary/preliminary results (including if they have confirmed ILI reported features, other findings, etc.);
        ii.   Coating condition description before sandblasting, including if electrolytes were present (if possible);
        iii.  Relevant photos of the coating before sandblasting;
        iv.  Soil type and description;
        v.  Cathodic Protection (CP) value measured in the ditch.

c)  For sites where Enbridge has decided that pipe repair was not necessary, provide a summary of the fitness-of-service (FFS) evaluation;

d)  A summary of the last CP Survey for sections 9L1 and 9L2;

e)   Describe how the safe repair pressure of 502 psi, implemented to allow the grinding/buffing of deeper seam weld and GW toe cracks, was calculated. Include Enbridge’s evaluation criteria and copies of relevant pages related to Enbridge standards, code, etc.

f)   For the dig site at 4AL1 GW 26000 (i.e. on NPS 30 near the rupture site of NPS 36): provide the updated schedule for excavation, assessment and repair (if applicable).

4.  Repair/mitigation method : 
a)  Provide a detailed description of mitigation measure(s) that Enbridge will implement for the field assessed anomalies to ensure the safe operation of both exposed pipe joints, including the start and end points of each mitigation measure. Explain Enbridge's rationale for selecting each measure.
 
b)  If Enbridge decides to not further mitigate some features, please explain the rationale and the criteria for these decisions. 
 
c)  Confirm if Enbridge will grind the sides of the grinding locations where there are the appearance of “sharp edges” in order to eliminate any potential stress concentrators. If not, explain why.
 

Due date: 2019-05-09

Date closed: 2019-05-09
Note: the date closed is the date that the inspector completed their review of the company corrective actions for adequacy and determined that no further actions are required.

Reason closed: Requirement met

Compliance achieved: Yes

Observations (company follow-up required)

Identified non-compliances to company plans or procedures are non-compliances either to: