Compliance Verification Activity Report: CV2122-205 - NOVA Gas Transmission Ltd.


Compliance verification activity type: Field Inspection

Activity #: CV2122-205
Start date: 2022-02-23
End date: 2022-02-24


Regulated company: NOVA Gas Transmission Ltd.

Operating company: TransCanada PipeLines Limited

Province(s) / Territory(s):


Related events:

Rationale and scope:

Integrity construction inspection for the North Central Corridor Remediation Project to verify compliance with the OPR, CSA Z662-19 and Order XG-008-2021.

Compliance tool(s) used:

Facility details


Regulatory requirements

Regulatory requirements that apply to this activity:

Regulatory instrument number(s):

Observations (no outstanding follow-up required)

Observation 1 - Day 1 - Construction Office Opening Meeting & Project Quality Assurance and Control

Date & time of visit: 2022-02-23 09:45

Discipline: Integrity Management




The CER inspectors met NGTL representatives (TC Energy (TCE) staff) at the construction office located beside the Woodenhouse compressor station.

CER lead inspector presented the purpose, scope, and goals of the inspection; the history of the project was reviewed to get all participants familiar with the two incidents (INC2013-146 and INC2020-047)  that led to the replacement project.

Roles and expectations of CER staff and company staff, Inspection Officer authority, and Compliance and enforcement tools were presented by CER lead inspector.

Site-specific safety orientation was provided by the construction manager and CER inspectors signed off on it.

Sites and facilities to be inspected and logistics were discussed.

The project has two main construction sites (HDD Entry and Exit points). At the time of the inspection, most HDD activities had been completed, there was some welding going on at the exit point, the bypass was partially built.  TCE explained that no bending will be happening on-site and that the pipe will be sent to a shop for bending. No coating was ongoing at the time of the inspection.

TCE explained it is the prime contractor for the project and the general contractor on site is Robert B. Somerville Co Ltd (RBS).  TCE explained that for in-service welds, the QC/QA in done by TC energy welding inspectors.  For production welds, the QC is done by the contractor welding inspector, with a minimum of 10% of the weld QC witnessed by a TCE welding inspection, and the production welds QA is done by TCE. The TCE welding inspectors met in the field indicated that they witnessed almost all the production weld inspections, exceeding TCE criteria. In terms of verifying the welders are following the welding procedures, TCE explained that at least one full set of parameters per welder per week is completed.

So far there had been only one weld repair. TCE confirmed that it is using CSA Z662-19 workmanship repair criteria for the welds, except for the seam weld on the stopples which uses the ASME B31.3 criteria. The welding procedure data sheets and a list of qualified welders were provided for the welding in progress that day.

TCE explained that when materials are received it is inspected by the contractor and TCE conducts the QA on the inspection reports.

TCE explained that the two TCE welding inspectors are also the qualified coating inspectors on site.

The project change management was discussed and TCE indicated that 15 Request for Information (RFI) from the field construction crew had been submitted to date. One of those RFI was about a request from the construction crew to replace some of the backfill material, specified as clay in the Issued for Construction (IFC) drawings, with the native muskeg material. TCE explained that the RFI is still being reviewed by the design Subject Matter Experts (SMEs) to provide a decision to the field construction crew. CER inspectors note that the replacement of the backfill material without proper communication with the design SMEs was an issue identified in incident INC2020-047. In this case, the appropriate review process appears to be taking place with the RFI, which was one of the corrective and preventive actions identified for INC2020-047.

TCE confirmed that the screw anchor pull test requirements were listed in the IFC drawings. Drawing # 1873-02-ML-02-002 provides the details for the screw anchors for the NPS 36 pipe and it specifies a pull test force of 84.5 kN. TCE indicated that a TCE general inspector or the Assistant Construction Manager will verify the pull tests.

Compliance tool used: No compliance tool used

Observation 2 - Day 1 - HDD Exit Point

Date & time of visit: 2022-02-23 14:00

Discipline: Integrity Management




The TCE Welding Inspector was on site to monitor the welding activities. Welders had just completed the welding of a tee on the in-service North Central Corridor Loop. MPI had been completed on the welds. The TCE Welding Inspector explained the verifications that he conducts in the field to ensure the quality of the welds. For the weld just completed on the in-service NCCL, he explained that he had verified the welding parameters for the two welders. The welders were # W34 and W42, and the welding procedure used was SLVE-09-ISW. He also explained that he verifies all the welds completed on the in-service pipe and most of the welding for the project, which is above the minimum requirement of 10% of the welds as per TCE standards. TCE’s Senior Welding Subject Matter Expert explained that the phased array NDE is conducted 12 hours after completing the welding. The ditch was sloped properly and with adequate access and egress.


The contractor welding inspector was also on site and he had just completed the inspection of the weld completed on the temporary by-pass. He explained the verifications that he conducts to ensure the quality of the welds, including but not limited to, verifying the parameters for one full weld for each welder per week. The weld had been completed by welders # W2 and W3 using the CSA-04 Rev 4 welding procedure. CER inspectors verified that the welding rods used for that weld complied with the welding procedure. The contractor welding inspector explained that they are using fresh low hydrogen rods every day and that the rods are kept in the oven during the day. Any rods remaining at the end of the day are disposed of. 


The new crossing pipe was extending out of the HDD exit point. The observable abrasion-resistant coating of the pipe appeared to be in good condition. TCE explained that a continuity test will be conducted in the coming days to verify the condition of the coating. TCE explained that they had an HDD inspector on site for the HDD and that the HDD path was completed within the parameters of acceptability. The pipe used for the HDD was hydrotested prior to the pull and will be hydrotested again prior to completing the project.


Some pipe joints were stored on site and some of them will be sent to a fab shop for cold bending for the project. Some pipe joints were selected for demonstrating traceability with the Material Testing Records (MTRs). TCE provided the MTRs for a sample of joints selected by CER inspectors. The markings on the pipe observed indicated it was as per TCE’s specifications for the project.

Compliance tool used: No compliance tool used

Observation 3 - Day 2- Construction Office– Welding Program Records Review

Date & time of visit: 2022-02-24 10:25

Discipline: Integrity Management




This part of the inspection was mainly focused on documentation review. TCE’s Sr. Welding Subject Matter Expert presented one of the welding turnover binders to CER inspectors. TCE explained that the Welding procedure specifications (WPS) for the entire project (both in-service and production welds) were TCE procedures. The TCE Sr. Welding Subject Matter Expert indicated that he attended the welders’ qualification tests for the tees long seam welds. The welding turnover binder was well organized and a sample of the following records and documents were reviewed:

A list of qualified welders was presented and the welders witnessed on the previous day were qualified for those welds according to that list.  TCE explained that the welding inspectors are qualified as per TCE specs, API 1169 and NACE level I for coating. Welding parameters from an in-service weld conducted at the entry point were presented to the CER inspectors by TCE. CER inspectors were able to confirm that the recorded parameters were in the range defined in the WPS.

TCE explained that a safe excavation pressure and temperature have been established for the project. TCE explained that they are checked daily in the morning with the control center and just prior to drilling or welding a stopple on the pipe.

Compliance tool used: No compliance tool used

Observation 4 - Day 2 - HDD Entry Point

Date & time of visit: 2022-02-24 14:30

Discipline: Integrity Management




Crews were installing slab valves on stopples #1 and #2. The ditch was sloped properly and with adequate access and egress. The stopples and the pipe outside of the stopples had supports. TCE explained that the supports were designed to address the extra weight created by the stopples and that they were designed to allow the pipe to slide within to support to avoid restricting the displacement created by thermal expansion. Hot tap towers were installed on stopples #3 and #4 in preparation for drilling.


The temporary by-pass piping was hoarded and heated in preparation for hydrotest. TCE explained that the bypass piping will also be heated to ensure an installation temperature of -5 Celsius minimum. TCE explained that they will have a hydrotest inspector to observe the hydrotest that will be conducted by the contractor.


A crew was conducting a continuity test on the HDD pipe segment. They were conducting static readings at the time.

Compliance tool used: No compliance tool used

Observations (company follow-up required)

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

- the condition of an authorization document that requires the implementation of that plan or procedure; or

- the relevant section of the regulations that requires implementation of that plan or procedure including those sections that require implementation of plans or procedures as a part of a Program