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How does PHMSA define Gathering, Transmission, Distribution, & Production Pipelines?

Pipeline and Hazardous Materials Safety Administration (PHMSA) classifies different types of pipelines according definitions in 49 CFR 191, 49 CFR 192, the API Recommended Practice 80 (RP80) First Edition April 2000.

Transmission Pipeline

§192.3 defines Transmission Line as: a pipeline, other than a gathering line, that:

(1) Transports gas from a gathering line or storage facility to a distribution center, storage facility, or large volume customer that is not down-stream from a distribution center;

(2) operates at a hoop stress of 20 percent or more of SMYS; or

(3) transports gas within a storage field.

Distribution Pipeline

And the code defines Distribution Line as a pipeline other than a gathering or transmission line.

Production Pipeline

Production Pipelines are not defined in §192. However, §192.8(a)(1) states:

(a) An operator must use API RP 80 (incorporated by reference, see § 192.7), to determine if an onshore pipeline (or part of a connected series of pipelines) is an onshore gathering line. The determination is subject to the limitations listed below. After making this determination, an operator must determine if the onshore gathering line is a regulated onshore gathering line under paragraph

(b) of this section. (1) The beginning of gathering, under section 2.2(a)(1) of API RP 80, may not extend beyond the furthermost downstream point in a production operation as defined in section 2.3 of API RP 80. This furthermost downstream point does not include equipment that can be used in either production or transportation, such as separators or dehydrators, unless that equipment is involved in the processes of “production and preparation for transportation or delivery of hydrocarbon gas” within the meaning of “production operation.

RP80 provides a definition for Production Operations (Section 2.3) as “the piping and equipment used for production and preparation for transportation or delivery of hydrocarbon gas and/or liquids and includes the following processes: (a) extraction and recovery, lifting, stabilization, treatment, separation, production processing, storage, and measurement of hydrocarbon gas and/or liquids and (b) associated production compression, gas lift, gas injection, or fuel gas supply. RP80 Sections and 2.4.4(j) provides support as to the functional classification of the Biogas Line.

Gathering Pipeline

49 CFR 192.3 defines a Gathering Line as a pipeline that transports gas from a current production facility to a transmission line or main.

RP80 defines a Gathering Line in a more detailed discussion. RP80 (Section 2.2) states:

Gathering Line -

(a) means any pipeline or part of a connected series of pipelines used to

(1) transport gas from the furthermost downstream point in a production operation to the furthermost downstream of the following endpoints, which physically may have intermediate deliveries (to other production operations, pipeline facilities, farm taps, or residential/commercial/industrial end users) that are not necessarily part of the gathering line:

(A) the inlet of the furthermost downstream natural gas processing plant, other than a natural gas processing plant located on a transmission line,

(B) the outlet of the furthermost downstream gathering line gas treatment facility,

(C) the furthermost downstream point where gas produced in the same production field or separate production fields is commingled,

(D) the outlet of the furthermost downstream compressor station used to lower gathering line operating pressure to facilitate deliveries into the pipeline from production operations or to increase gathering line pressure for delivery to another pipeline, or (E) the connection to another pipeline downstream of:

(i) the furthermost downstream endpoint identified in (A), (B), (C) or (D), or (in the absence of such endpoint)

(ii) the furthermost downstream production operation; or

(2) transport gas from a point other than in a production operation exclusively to points in or adjacent to one or more production operations or gathering facility sites for use as fuel, gas lift, or gas injection gas within those operations; and (b) does not include a natural gas processing plant.

Gas Gathering Requirements

The Pipeline Safety: Safety of Gas Transmission Pipelines: Repair Criteria, Integrity

Management Improvements, Cathodic Protection, Management of Change, and Other Related Amendments otherwise known as the “Mega Rule,” effective May 16, 2022, requires operators of all onshore gas gathering lines to report incidents and file annual reports under §191. This Final Rule provides for new Type C and Type R regulated gathering lines with certain regulatory compliance requirements defined in §192.8. Type C gathering lines are defined as gas gathering lines in Class 1 locations that are steel and have an outer diameter of 8.625 inches or greater and operate at a maximum allowable operating pressure (MAOP) producing a hoop stress of 20% or more of specified minimum yield strength (SMYS), or if the pipeline is non-metallic and an outer diameter of 12.75 inches or greater, or the stress level is unknown, and operates above 125 pounds per square inch gauge pressure. Type R gathering lines are defined as steel gas gathering lines that have an outer diameter of less than 8.625 inches and MAOP less than 20% SMYS, or non-metallic with an outside diameter of less than 12.25 inches, and an MAOP of less than 125 psig. Type R lines are subject to reporting requirements under §191 but are not regulated onshore gathering lines under §192.

Incidental Gathering

RP80 Section states the following:

In the case of gas processing or gas treatment, the connection to a transmission line is generally contained within the boundaries of the facility. This is not always the case, however. The gathering line operator may have to move the gas through a pipeline some additional distance from the plant to another pipeline. The pipeline moving the gas from the plant to another pipeline is termed “incidental gathering.” The “incidental gathering” resumes at the plant outlet and continues to the other pipeline connection. Incidental gathering may also occur when a compressor is a potential endpoint. Incidental gathering normally is present when the point of last commingling is the last “identified endpoint.” From a functional standpoint, this section of incidental gathering line is no different from the rest of the gathering system. The definition, therefore, includes recognition that gathering may continue downstream of the last endpoint identified by processing, treatment, commingling, or compression activities to the connection with another pipeline.

The preceding code citations are only a brief overview of how PHMSA classifies different portions of pipeline. In making a determination of what portion of an operator's system is gathering, transmission, distribution or production, involves a thorough knowledge of the preceding code as well as how to properly apply past PHMSA interpretations involving similar pipeline circumstances. The Oak Tree Group understands that it can be confusing and difficult to classify a pipeline system, and would be happy to review your pipeline system and provide our professional opinion on how your system should be classified.

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