This brief, "MONITORING AND CONTROL PARAMETERS OF GAS PIPELINE BY USING PLC AND SCADA SYSTEM" is schematic. It lists common types of PLCs in the field a/o 2020 that monitor or actuate flow from either terminal point and along the loop. Anyone of these could be compromised by malware.

I'm idly looking for PNG pressure containment parameters, comparable to Nord Stream 1 casing which I will assume is not reinforced up to RU-TR Turkstream II 2022 spec. So far, most the public lit covers leaks typically attributed to low-pressure deformation or unidentified corrosion of moving parts and joint seals, the most frequent maintenance issues.

OG was a successful software attack for a few reasons. It ran with instructions to save data, hijack firmware, and mask data reporting by PLCs in the network.

LANGNER: So a centrifuge, it's driven by an electrical motor, and the speed of this electrical motor is controlled by another PLC, by another programmable logic controller.  
CHIEN (VO): Stuxnet would wait for 13 days [ARCHIVE VIDEO: Natanz engineers inspecting physical equipment] before doing anything, because 13 days is about the time it takes to actually fill an entire cascade of centrifuges with uranium. They didn't want to attack when the centrifuges essentially empty or at the beginning of the enrichment process.  
[ARCHIVE VIDEO: Natanz operators room stations, panel displays of PID controller blocks] What stuxnet did was it actually would sit there during the 13 days and basically record all of the normal activities that were happening and save it. And once ithey saw them spinning for 13 days, then the attack occurred. Centrifuges spin at incredible speeds, about 1,000 hertz. [VISUAL: 3-D spline simulation]
LANGNER (VO): They have a safe operating speed, 63,000 rpm.
CHIEN (VO): Stuxnet caused the uranium enrichment centrifuges to spin up to 1,400 hertz. [VISUAL: OG document detail, sub-routine parameter]
LANGNER (VO): Up to 80,000 rpm.
CHIEN: What would happen was those centrifuges would go through what's called a resonance frequency. It would go through a frequency at which the metal would basically vibrate uncontrollably and essentially shatter. THere'd be uranium gas everywhere. And then the second attack they attempted was they actualy tried to lower it to 2 hertz.
LANGNER: They were slowed down to almost a standstill.
CHIEN: And at 2 hertz, sort of an opposite effect occurs. You can imagine a toy top that you spin [VISUAL    : 3-D spline simulation] and as the top begins to slow down, it begins to to wobble. That's what would happen to these centrifuges. They'd begin to wobble and essentially shatter and fall apart. And instead of sending back to the computer what was realy happening, it would send back that old data that it had recorded. So the computer's sitting there "thinking" [ARCHIVED STILL FRAMES: Natanz operators room, monitor disply of PID block diagram, control switch stations] "Yep, running at 1,000 hertz. Everything is fine. But those centrifuges are potential spinning up wildly, a huge noise would occure. It'd be like, you know, a jet enginve. SO the operators then would know, 'Whoa, something is going wrong here.' They might look at their monitors and say, ' hmmmm, it says it's 1,000 hertz,' but they would hear that in the room something gravely bad was happening.
LANGNER: Not only are the operators fooled into thinking everything's normal, but also any kind of automated protective logic is fooled.