Risk-Based Leak Survey Program

(a)This section applies to each operator of a gas distribution system that is subject to the requirements of 49 CFR Part 192.#

(b)Each operator shall have either a prescriptive or a risk- based program for leak surveys for its pipeline systems that complies with the requirements of this section. Such program shall require a designation on a system by system basis or by segments within each system whether the operator has chosen to use the risk based leak survey program that complies with the requirements of subsections (c) through (f) of this section or the prescriptive leak survey program that complies with the requirements of subsection (g) of this section.#

(c)Each operator shall create a risk model on which to base its leak survey program to identify those systems or segments within systems that pose the greatest hazard and thus will be inspected for leaks more frequently. The risk model shall identify risk factors and determine the degree of hazard associated with those risk factors. The operator shall establish the leak survey frequency based on the degree of hazard for each system or segment within a system.#

(d)Each operator shall periodically re-evaluate each pipeline system or system segment and update its leak survey inspection program to address any changes that may be identified through the monitoring of the pipeline system in accordance with the requirements imposed by 49 CFR §192.613 (relating to Continuing Surveillance). Each operator shall not less than every three years at intervals not exceeding 39 months review its leak survey inspection program. Each operator shall review its leak survey inspection program within 30 days in the following circumstances:#

(1)to add a new system or segment being put into operation; or#

(2)if, for any system or segment, there has been a ten percent increase in the number of leaks being upgraded or a ten percent increase in the number of unrepaired leaks.#

(e)Based on the particular circumstances and conditions, an increased frequency beyond that required by 49 CFR §192.723(b)(1) and (2), may be warranted. Surveys should be conducted more frequently in those areas with the greatest potential for leakage and where leakage could be expected to create a hazard. Each operator should consider the following factors in establishing an increased frequency of leakage surveys:#

(1)pipe location, which means proximity to buildings or other structures and the type and use of the buildings and proximity to areas of concentrations of people;#

(2)composition and nature of the piping system, which means the age of the pipe, materials, type of facilities, operating pressures, leak history records, and other studies;#

(3)the corrosion history of the pipeline, which means known areas of significant corrosion or areas where corrosive environments are known to exist, cased crossings of roads, highways, railroads, or other similar locations where there is susceptibility to unique corrosive conditions;#

(4)environmental factors that affect gas migration, which means conditions that could increase the potential for leakage or cause leaking gas to migrate to an area where it could create a hazard, such as extreme weather conditions or events (significant amounts or extended periods of rainfall, extended periods of drought, unusual or prolonged freezing weather, hurricanes, etc.), particular soil conditions, unstable soil or areas subject to earth movement, subsidence, or extensive growth of tree roots around pipeline facilities that can exert substantial longitudinal force on the pipe and nearby joints; and#

(5)any other condition known to the operator that has significant potential to initiate a leak or to permit leaking gas to migrate to an area where it could result in a hazard, which could include construction activity near the pipeline, wall-to- wall pavement, trenchless excavation activities (e.g., boring), blasting, large earth-moving equipment, heavy traffic, increase in operating pressure, and other similar activities or conditions.#

(f)The assignment of inspection priorities is based on the degree of hazard associated with the risk factors assigned to the pipeline system or segments within a system. The determination of leak survey frequency is determined by classifying each pipeline segment based on its degree of hazard associated with each risk factor. Each operator shall establish its own risk ranking for pipeline segments to determine the frequency of leakage surveys. Based on a ranking from high to low, each operator shall schedule leak inspections for a given pipeline system or segment within a system on a time interval necessary to address the risks. The time interval may range from quarterly to every five years.#

(g)Operators electing to use a prescriptive leak survey program shall conduct leak surveys no less frequently than:#

(1)Once each calendar year at intervals not exceeding 15 months for all systems within a business district;#

(2)every five calendar years at intervals not exceeding 63 months for non-business district polyethylene systems or segments within a system;#

(3)every three calendar years at intervals not exceeding 39 months for all other non-business district cathodically protected steel systems or segments within a system; and#

(4)every two calendar years at intervals not exceeding 27 months for all other non-business district systems or segments within a system.#

Source Note: The provisions of this §8.206 adopted to be effective September 1, 2008, 33 TexReg 4868; amended to be effective January 6, 2020, 45 TexReg 121#