PHMSA – What next?

It was encouraging to see the sold-out attendance at these two events and the firm commitment of the many pipeline operators who attended to the pursuit of the zero leaks goal. I was keen to hear the update from PHMSA on the fate of their pending rule requiring valves and/or rupture detection on hazardous liquid onshore pipelines and the Liquids Mega Rule that will require the installation of leak detection systems on all hazardous liquid pipelines. Publishing of the Liquids Mega rule was suspended pending a review by the nascent Trump regime in January. PHMSA speakers indicated that the Liquids Mega Rule will still happen, stating “wait and see”. The PHMSA stance on the valve and rupture rule was similar, the PHMSA speaker said: “the rule is in limbo, stay tuned”.  PHMSA stated that the agency is delayed as it struggles to frame the proposed rules to meet the Trump administration directive that two existing rules must be eliminated for every new rule published. Speaking to conference attendees I feel that these rules will eventually be published as there is support for them on both sides of congress, from some pipeline operators and from environmentalists.

More help for pipeline operators feeling left behind - Improving Leak Detection System Design Redundancy & Accuracy – PHMSA guidance document.

PHMSA will soon issue comprehensive guidelines to assist in the designing an appropriate LDS for all pipelines that will be accessible to all operators – including the smaller ones – without extended and laborious front-end engineering. This approach will concentrate on certain key issues:

1. Beginning any LDS design process with a systematic focus on assessing requirements.

2. Accepting that one single technology will probably not provide perfect performance for all objectives, on a given pipeline. Therefore, a key issue is exploring ways to combine multiple technologies / physical principles into one system to address each requirement optimally.

3. Allowing the operator to be able to predict performance – and therefore cost/benefit – more reliably from the design.

API 1175 Tips

Leak detection is consequence management.  Speakers at the 1175 workshop emphasized that while leak detection will not change the number of pipeline spills, good leak detection and a good leak detection program can minimize the consequence of a leak. Fast detection and response to a leak will significantly reduce the volume of liquid spilled.

Experienced pipeline operators emphasized the importance of first assuming a leak is real and then proving whether the leak alarm is false or not.

Some attendees and presenters stated that they are actively exploring the deployment of rupture based leak detection systems. One presenter, a senior manager of a major US pipeline company stated that in their experience CPM leak detection systems are good for detecting leaks seized between 2% and 10% of flow, they feel they need to add rupture detection to guarantee fast rupture detection with the high reliability.  The key to safe operation, stated this manager, is to keep the pipeline shutdown following a rupture alarm.

Good metrics on the performance of the components needed to support leak detection can include, the number of instrument outages, number of communications outages, and CPM availability. It is important to document false alarms, identify what caused them (bad comms, an operation etc.), and fix the cause of the false alarm. Set KPIs to measure the number of false alarm and the number of pipeline shutdowns.

By: Atmos International
Date: 11 October 2019