Compliance verification activity type: Field Inspection
Team:
Regulated company: NOVA Gas Transmission Ltd.
Operating company: TransCanada PipeLines Limited
Province(s) / Territory(s):
Discipline(s):
Related events:
Rationale and scope:
Pipeline Monitoring, Control, and Protection Inspection (to be completed with IA meeting)
Compliance tool(s) used:
Facilities:
Facility Types
Life-cycle Phases
Regulatory requirements that apply to this activity:
Observation 1 - Burton Creek Compressor Station
Date & time of visit: 2021-08-24 09:30
Discipline: Integrity Management
Categories:
Facility:
Observations:
NGTL provided a site specific orientation and completed a Job Safety Analysis. Electronic sign in and out procedures were in place. The site has three compressor units, identified as A1, A2, and A3, with only A3 running at the time of the inspection. The A3 unit was put in service in September 2020. There are three main lines going through the station, two 36 in lines and one 42 in. The station MOP is 5825 kPa. CER inspectors verified on the local computer that the Discharge Pressure Control Override (DCPO) is set at 5825 kPa. NGTL explain that the pressure is controlled by controlling the speed of the compressor units and that the DCPO would initiate a speed reduction on reaching the MOP. The Station Shutdown Restartable (SSDR) would initiate a station shutdown at 105% MOP. The mechanical Pressure Safety Valves (PSVs) are set to fully open at 110% MOP. In addition to the PSVs, the station would initiate a high pressure shutdown at 108 or 110% MOP (dependent on the sensitivity of the station equipment) which would cause all compressor units to shut down, isolate the station and blow down the station. There is a station discharge temperature shutdown that would be triggered if the discharge temperature reaches 49 Celsius for 10 minutes. The station was operating at about 5790 kPa and 25.1 Celsius at the discharge at the time of the inspection. This station is not connected to utility power and uses gas generators for the main power and for auxiliary power. A battery Uninterruptible Power System (UPS) is used to ensure the transition between the main power and auxiliary generators during a power loss event. An alarm would be generated to Gas Control in the event of a power loss and a technician would be sent to verify the situation on site. An alarm would be also be generated to Gas Control in the event of a communication loss and a technician would be sent to verify the situation on site. The station is not manned in the evening or weekends and it would take approximately over 1 hour for a technician to drive to the site. The station suction is equipped with a scrubber to prevent liquids to reach the compressor units. The scrubber is equipped with level switches and drains automatically in the scrubber tank when needed. There is also a high level switch in the scrubber tank which would trigger a shutdown of the compressor unit and isolation of the station if the liquid level reached that switch. The on-site technicians present for the inspection explained that the preventative maintenance inspection tasks for the site are generated by SAP. They also explained that NGTL has a process in place to ensure these tasks are completed on time. The station is equipped with station ESD push buttons located at several locations on site, including near the emergency exits and the main gate. Unit ESD push buttons were located inside each compressor buildings and station ESD push buttons are also located on the outside near the doors of the compressor buildings. The A3 compressor unit had an enclosure for its engine. The enclosure has fire detection and a CO2 fire suppression system. If the fire suppression system is initiated, a strobe light and audible alarm will be activated to warn of the situation and of the low oxygen hazard in the enclosure. There are five PSVs on site and two station blowdowns. Valves upstream of the PSVs and station blow downs were locked in the open position. The vents had caps to prevent water ingress and corrosion in the piping. The station is equipped with aerial coolers to ensure an appropriate discharge temperature. CER inspectors observed that signs with the company name, emergency phone number, signage warning of hazards and PPE requirements, and non-smoking signs were posted at the site main entrance. The compressor station is fenced with several egress gates in addition to the main site access. CER inspectors observed that the pig trap coating of the A1 and A2 compressor units at the air-to-soil interface was absent or in poor condition. The CER inspectors observed numerous valves that were locked open or closed that had plastic tags on the valves that identified whether they were open or closed and a warning not to change the status. The inspectors observed some valves that were locked that did not have similar tags. The NGTL technician indicated that they were moving toward this system and had not added the tags to all the valves. The inspectors indicated that the valves open or closed status could be verified by observing the status indictor on the valve to determine whether it was open or closed and the tag was in addition to the valve status indicator.
Compliance tool used: No compliance tool used
Observation 2 - Burton Creek Compressor Station - Notice of Non-Compliance - Building Ventilation
There are three compressor buildings each housing a compressor unit. The compressor buildings are equipped with gas detection. At 10% of the Lower Explosive Limit (LEL), an alarm is initiated, and the building ventilation is started. The compressor building are also equipped with fire detection (fire eyes and temperature probes). Upon fire detection, a station ESD is initiated, and the building ventilation is stopped. However, CER inspectors observed that the compressor buildings for units A1 and A2 had temporary ventilators installed in the building and these fans were not controlled by the Programmable Control Logic (PLC). Therefore, the temporary ventilators did not comply with CSA Z662-19 clause 4.14.1.3 (b). NGTL explained that the temporary fans are installed during the hot summer months to help cool the station. NGTL removed the tempororary ventilation prior to the completion of this inspection but CER inspectors issued a Notice of Non-Compliance (NNC) to ensure a permanent solution is implemented.
Compliance tool used: Notice of Non-compliance (NNC)
Regulatory requirement:
Relevant section(s):
Company action required:
1) NGTL to explain if it uses temporary ventilation in other compressor buildings under CER jurisdiction at any of TC Energy entities that do not satisfy the requirment of CSA Z662-19 clause 4.14.1.3 (b) and if yes, NGTL is to provide a list of those compressor stations. 2) NGTL is to provide a plan to permanently address the ventilation issue at the Burton Creek compressor station and at any other compresor stations identified in (1) above and prevent it from re-occuring.
Due date: 2021-11-30
Date closed: 2022-03-24 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
Observation 3 - Burton Creek Compressor Station - Information Request #1 - Valve Maintenance
Inspectors noted the stems of two small diameter valves that were sticking out of the ground. In addition, a 3-inch valve was observed that was not buried but it in a depression in the ground where soil had been removed around it. In the event of rain, water would pool here and the valve could be under water. No observable valve numbers or markings were identified. The Inspectors asked if the piping associated with these valves was still in service, energized, and what process the piping and valves were associated with. CER inspectors asked whether these valves are regularly inspected, what maintenance schedule was required for these valves, and, if there are no valve identification markings and they are inaccessible, how are they inspected. NGTL representatives were unable to provide answers at the time of the inspection and the CER inspectors issued an Information Request for NGTL to provide the information.
Compliance tool used: Information Request (IR)
NGTL to answer the following questions: 1) Explain if the piping associated with these valves is still in service, energized and what process the piping and valves are associated with. 2) Explain whether these valves are regularly inspected, what maintenance schedule is required for these valves and, if there are no valve identification markings or if they are inaccessible, explain how they are inspected and how the inspections are recorded.
Due date: 2022-02-10
Observation 4 - Burton Creek Compressor Station - Information Request #2 - Bolting of Actuator Flange
The CER inspectors observed the older Bettis actuator flange attachments on the crossover valves did not have the studs protruding through the actuator flange attachment. The studs were threaded approximately halfway into the Bettis actuator attachment (note the actuator flange had threads and bolts were not required on the actuator side of the connection). The CER inspectors observed that the newer Bettis actuator attachments had the studs protruding beyond the attachment. CER Inspectors issued an Information Request for to clarify whether the Bettis attachment was under load due to pressure and whether the studs are required to protrude through the Bettis attachment.
NGTL to answer the following questions:1) Clarify whether the Bettis attachment was under load due to pressure and whether the studs are required to protrude through the Bettis attachment.
Due date: 2021-11-15
Date closed: 2022-01-12 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.
Observation 5 - Burton Creek Compressor Station - Information Request #3 - Records of Inspection
CER inspectors requested NGTL to provide the records of inspection of one of the station PSV. See Information Request.
NGTL is to provide the records for the last two five-year inspections of PSV AO-PSV-0061.
Observation 6 - Turner Valley Compressor Station
Date & time of visit: 2021-08-24 15:20
NGTL provided a site specific orientation and completed a Job Safety Analysis. Electronic sign in and out procedures were in place. The site has three compressor units, identified as A1, A2, and A3, with only A3 running at the time of the inspection. The A3 unit was put in service in September 2020. There are two main lines going through the station yard, one 36 inch and one 42 inch. Units A1 and A2 work in series within their own sub-station and unit A3 works independently of A1 and A2. A3 and the A1-A2 sub stations each have their own scrubbers, coolers, sub-station ESD, and pressure and temperature control and protection systems. Work was in progress at the station to replace some compressor unit engines and some valves. The station MOP is 5825 kPa. CER inspectors verified on the local computer that the Discharge Pressure Control Override (DCPO) is set at 5825 kPa. NGTL explained that the pressure is controlled by controlling the speed of the compressor units and that the DCPO would initiate a speed reduction on reaching the MOP. The Station Shutdown Restartable (SSDR) would initiate a station shutdown at 105% MOP. The mechanical Pressure Safety Valves (PSVs) are set to fully open at 110% MOP. In addition to the PSVs, the station would initiate a high pressure shutdown at 108 or 110% MOP (depending on the sensitivity of the station equipment) which would cause all compressor units to shut down, isolate the station and blow down the station. There is a station discharge temperature shutdown that would be triggered if the discharge temperature reaches 49 degree Celsius for 10 minutes. This station is connected to utility power and uses gas generators for auxiliary power. A battery Uninterruptible Power System (UPS) is used to ensure the transition between the main power and auxiliary generators during a power loss event. An alarm would be generated to Gas Control in the event of a power loss and a technician would be sent to verify the situation on site. An alarm would be also be generated to Gas Control in the event of a communication loss and a technician would be sent to verify the situation on site. The station is not manned in the evening or weekends and NGTL indicated a technician could be on site within an hour. The sub stations suctions are equipped with scrubbers to prevent liquids to reach the compressor units. The scrubbers are equipped with level switches and drain automatically in the scrubber tanks when needed. There is also a high level switch in the scrubber tanks which would trigger a shutdown of the compressor units and isolation of the stations if the liquid level reached that switch. There are three compressor buildings each housing a compressor unit. The compressor building is equipped with gas detection. At 10% of the Lower Explosive Limit (LEL), an alarm is initiated, and the building ventilation is started. The compressor building is also equipped with fire detection (fire eyes and temperature probes). Upon fire detection, a station ESD is initiated, and the building ventilation is stopped. The station is equipped with station ESD push buttons located at several locations on site, including near the emergency exits and the main gate. Unit ESD push buttons were located inside each compressor buildings and station ESD push buttons we also located on the outside by the doors of the compressor buildings. The A3 compressor unit had an enclosure for its engine. The enclosure has fire detection and a CO2 fire suppression system. If the fire suppression system is initiated, a strobe light and audible alarm will be activated to warn of the situation and of the low oxygen hazard in the enclosure. The PSVs on site and station blowdowns vents had caps to prevent water ingress and corrosion in the piping. The station is equipped with aerial coolers to ensure an appropriate discharge temperature. CER inspectors observed that signs with the company name, emergency phone number, signage warning of hazards and PPE requirements, and non-smoking signs were posted at the site main entrance.The compressor station is fenced with several egress gates in addition to the main site access. CER inspectors observed that the pig trap coating of the A1 and A2 compressor units at the air-to-soil interface was missing or in poor condition.
Observation 7 - Turner Valley Compressor Station - Information Request #1 - Depressurizing Pig traps
CER inspectors noticed that that pig receiver had limited points to verify depressurization before opening the quick opening closure door. NGTL staff accompanying the inspectors do not work on the pig launcher and receiver therefore they were unfamiliar with the procedure used to verify depressurization. CER inspectors issued an Information Request to obtain the procedure to verify depressurization before opening the quick opening closure door.
NGTL to provide the procedure to verify depressurization before opening the quick opening closure doors of the pig traps observed at the Turner Valley compressor station.
Observation 8 - Turner Valley Compressor Station - Information Request #2 - Records of Inspection
CER inspectors requested NGTL to provide the records of inspection of some of the station instrumentation. See Information Request.
NGTL to provide the following records of inspection: 1) The last two five-year inspection records for PSV AO-PSV-0062. 2) The last 2 inspection records for station discharge temperature transmitter AO-TI-0402. 3) The last 2 inspection records for station discharge pressure transmitter AO-PI-0402. 4) The last inspection records for the A1 compressor unit pressure transmitters.
Observation 9 - Quirk Creek Meter Station
Date & time of visit: 2021-08-24 17:00
NGTL provided a site specific orientation. The meter station is fed by the nearby Caledonian producer processing plant. The gas is then transported by a lateral (of an approximal length of 13 km) to the mainline system.The station is equipped with an H2S analyzer which is calibrated every six months. The H2S analyzer would trigger the station upstream isolation valve to close at 16 PPM of H2S.There are three meter runs equipped with orifice plates for metering.There is a scrubber upstream of the meter runs. The level of liquids in the tank for the scrubber is verified monthly.The meter station has a battery powered UPS system for auxiliary power. Gas Control would receive an alarm in the event of a power loss.The pressure control and over pressure protection equipment is located at the producer plant upstream of the station. If a high pressure or temperature is detected at the station, it would trigger an alarm and Gas Control personnel would contact the producer to address the situation.The primary pressure transmitters are inspected every six months and the secondary pressure transmitters are inspected when an anomaly is detected.CER inspectors observed that the coating of the meter runs at the air-to-soil interface was missing or in poor condition. The CER inspectors observed that no pig launching or receiving facilities were available for the lateral pipeline
Observation 10 - Torrington Compressor Station
Date & time of visit: 2021-08-25 09:30
NGTL provided a site specific orientation and completed a Job Safety Analysis. Electronic sign in and out procedures were in place. The site has one compressor unit, which was not running at the time of the inspection. There is a 36 inch mainline and a 24 inch mainline lateral going through the station. There is also a 16 inch lateral ending at this station. This is a bidirectional compressor station with a control valve skid that allows to send the product north or south by rerouting the gas in the desired direction. The MOP of the mainline is 5960 kPa and the MOP of the mainline lateral is 6205 kPa. The pressure at the station discharge at the time of the inspection was about 4860 kPa. NGTL explained that the pressure is controlled by controlling the speed of the compressor unit and that the DCPO would initiate a speed reduction on reaching the MOP. The Station Shutdown Restartable (SSDR) would initiate a station shutdown at 105% MOP. The mechanical Pressure Safety Valves (PSVs) are set to fully open at 110% MOP. In addition to the PSVs, the station would initiate a high pressure shutdown at 108 or 110% MOP (dependent on the sensitivity of the station equipment) which would cause all compressor units to shut down, isolate the station and blow down the station. There is a station discharge temperature shutdown that would be triggered if the discharge temperature reaches 49 degree Celsius for 10 minutes. This station is connected to utility power and uses a gas generator for auxiliary power. A battery Uninterruptible Power System (UPS) is used to ensure the transition between the main power and auxiliary generator during a power loss event. An alarm would be generated to Gas Control in the event of a power loss and a technician would be sent to verify the situation on site. An alarm would be also be generated to Gas Control in the event of a communication loss and a technician would be sent to verify the situation on site. The station is not manned in the evening or weekends and NGTL indicated a technician could be onsite within 1 hour. The station suction is equipped with a scrubber to prevent liquids to reach the compressor units. The scrubber is equipped with a PSV and NGTL explain this is because that station was designed to ASME B31.3. The scrubber is equipped with level switches and drains automatically in the scrubber tank when needed. There is a also high level switch in the scrubber tank which would trigger a shutdown of the compressor units and isolation of the station if the liquid level reached that switch. The compressor building is equipped with gas detection. At 10% of the Lower Explosive Limit (LEL), an alarm is initiated, and the building ventilation is started. The compressor building is also equipped with fire detection (fire eyes and temperature probes). Upon fire detection, a station ESD is initiated, and the building ventilation is stopped. The station is equipped with station ESD push buttons located at several locations on site, including near the emergency exits and the main gate. Unit ESD push buttons were located inside each compressor buildings and station ESD push buttons we also located on the outside near the doors of the compressor building. The compressor unit had an enclosure for its engine. The enclosure has fire detection and a CO2 fire suppression system. If the fire suppression system is initiated, a strobe light and audible alarm will be activated to warn of the situation and of the low oxygen hazard in the enclosure. There is another PSV on site to protect the station and two station blowdowns. Valves upstream of the PSVs and station blow downs were locked in the open position. The vents had caps to prevent water ingress and corrosion in the piping. CER inspectors observed that signs with the company name, emergency phone number, signage warning of hazards and PPE requirements, and non-smoking signs were posted at the site main entrance. The compressor station is fenced with several egress gates in addition to the main site access. There were three pig traps on site. One new receiver trap for the 16 inch lateral, one receiver trap for the 24 inch line, and one launcher trap for the 36 inch line. CER inspectors observed that the coating of the 24 inch and 26 inch pig traps at the air-to-soil interface was absent or in poor condition In addition, the CER inspectors noticed that that pig receiver had limited points to verify depressurization before opening the quick opening closure door.
Observation 11 - Keiver’s Lake Meter Station
Date & time of visit: 2021-08-25 11:25
NGTL provided a site specific orientation. The meter station is fed by two 6 inch lines coming from two nearby producer processing plants. The gas is then transported by a lateral to the mainline system.The meter runs are equipped with orifice plates for metering.There is a scrubber upstream of the meter runs. The level of liquids in the tank for the scrubber is verified monthly.The meter station has a battery powered UPS system for auxiliary power. The control room would receive an alarm in the event of a power loss.The pressure control and over pressure protection equipment is located at the producer plants upstream of the station. If a high pressure or temperature is detected at the station, it would trigger an alarm and control room personnel would contact the producer to address the situation.The primary pressure transmitters and inspected every six months and the secondary pressure transmitters are inspected when an anomaly is detected. There is a dew point tester to verify the water content of the gas on a monthly basis. There is a sampling system that feeds into a bottle sample which is analyzed for composition on a monthly basis. The CER inspectors observed no pig launching or receiving facilities were available for the lateral pipeline.
Observation 12 - Twinning Meter Station
Date & time of visit: 2021-08-25 12:05
NGTL provided a site specific orientation. The meter station is fed by a nearby producer processing plant. The gas is then transported by a lateral to the mainline system.Only one of the two meter runs is in service and the meter run is equipped with orifice plates for metering.There is a scrubber upstream of the meter runs. The level of liquids in the tank for the scrubber is verified monthly.The meter station has a battery powered UPS system for auxiliary power. The control room would receive an alarm in the event of a power loss.The pressure control and over pressure protection equipment is located at the producer plant upstream of the station. If a high pressure or temperature is detected at the station, it would trigger an alarm and control room personnel would contact the producer to address the situation.The primary pressure transmitters and inspected every six months and the secondary pressure transmitters are inspected when an anomaly is detected. There is a dew point tester to verify the water content of the gas on a monthly basis. There is a sampling system that feeds into a bottle sample which is analyzed for composition on a monthly basis. The CER inspectors observed no pig launching or receiving facilities were available for the lateral pipeline.
Observation 13 - Twinning Meter Station - Notice of Non-Compliance - Valve Position Indicator
CER inspectors noticed that all the station valves, including the station isolation valves were locked with chains. However, none of the valves, including the station isolation valves, had position indicators or means to indicate the current position of the locked valves. CSA Z662-19 Clause 10.9.6.1 requires “The open and closed positions of major valves shall be visually identifiable.” A Notice of Non-Compliance was issued to address this issue.
1) NGTL is to provide a plan to ensure compliance with CSA Z662-19 clause 10.9.6.1 at the Twinning Meter Station. 2) If a similar situation also exists at other meter stations, NGTL is to also provide a plan to address the situation at the other meter stations.
Due date: 2023-04-30
Date closed: 2023-05-03 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.
Observation 14 - Information Request - Emergency Shutdown Activated by Gas Detection
At the time of the inspection, CER inspectors understood that a gas dectection level of 40% of LEL in the compressor buidlings would trigger a station Emergency Shutdown (ESD) and that a station ESD shuts down the compressor units, isolates (by closing both the station suction and the discharge valves) and blows down the station. However, NGTL's comments on the draft report indicated that it was a "unit" ESD instead of a "station" ESD. CER inspectors need more information to cleary undertands what is shut down and blow down in the event of a gas detection at a level of 40% LEL in the compressor building to verify compliance with CSA Z662-19 clause 4.14.2.7. Clause 4.14.2.7 allows for a more limited shutdown and blowdown than the "Station" ESD defined in 4.14.2.4 but it is unclear if a "Unit" ESD satisfies the requirement of clause 4.14.2.7, especially if there are more than one compressor unit in the same building.
CER inspectors need more information to cleary undertands what is shut down and blow down in the event of a gas detection at a level of 40% LEL in compressor buildings to verify compliance with CSA Z662-19 clause 4.14.2.7. Clause 4.14.2.7 allows for a more limited shutdown and blowdown than the "Station" ESD defined in 4.14.2.4 but it is unclear if a "Unit" ESD satisfies the requirement of clause 4.14.2.7, especially if there are more than one compressor units in the same building. Please explain how NGTL is satisfying the requirement of CSA Z662-19 clause 4.14.2.7. Please provide a P&ID of the Burton Creek compressor station showing the compressor units and the pipping blown down and the isolation valves closed in the event of gas detection at 40% LEL in the compressor buildings.
Due date: 2021-11-24
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