Protecting America’s High Consequence Areas (HCAs)

Gas transmission pipeline operators are required to submit semi-annual performance measure reports on their Integrity Management programs, and annual reports on their pipeline infrastructure. PHMSA uses these reports – due at the end of February/August and March 15 respectively – to monitor industry progress in complying with requirements of the Gas IM Rule, to prioritize regulatory inspections, and to respond to inquiries about PHMSA’s oversight program.

These performance measure reports provide information pertaining to operators’ Integrity Management Programs, including the amounts of miles inspected and assessed, the operator’s repair activities addressing time-sensitive conditions, and the numbers and types of incidents, leaks, and failures occurring in HCA segments of their pipelines.

After performing quality checks, PHMSA posts these reports for the public, and you can view them here. Accessing these reports provides you with information that is aggregated across the entire industry, as well as information that is specific to individual operators.

For a basic overview of industry-wide progress being made under the Liquid IM Rule, please refer to the Quick Facts below.


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Quick Facts for Gas Integrity Management

Figure 1: Summary of Natural Gas Transmission Pipeline Repairs 2004-2007
Natural Gas Transmission Pipeline Repairs
Repairs in HCA segments2004200520062007Totals
   • Immediate category104261157255777
   • Scheduled category5993783384371,752
Total repairs in HCA segments7036394956922,529
Repairs outside of HCAsNot Available – Reporting Not Required
Note: Unlike hazardous liquid operators, gas transmission operators are not required to report on repairs outside of HCA segments of pipelines.


Figure 2

This figure shows the mileage of pipelines that have been inspected or assessed under the Gas IM Rule.

A single "inspection" covers one or more of the total identified threats for that pipeline segment. An "assessment" is complete when all identified threats have been inspected or tested for, oftentimes requiring more than one "inspection".

The top (blue) line represent inspections performed as a result of the Gas IM Rule—those performed on HCA segments as well as on segments adjacent to HCA segments. The bottom (red) line shows only the amount of HCA segments that have been fully assessed.

Figure showing the mileage of pipelines that have been inspected or assessed under the Gas IM Rule


Figure 3

This chart shows the number of pipeline repairs made under the Gas IM Rule from 2004 to 2007, inclusive. Since the rule's inception, some 2,537 repairs have been made to pipelines in HCAs, with 780 falling into the "Immediate" category and 1,757 in the "Scheduled" category.

Chart showing the number of pipeline repairs made under the Gas IM Rule


Figure 4

The average number of Incidents and Leaks (where a release of gas is involved) has dropped from an average of 122 per year in the first 3 years of the program to 72 in the most recent year.

Note: Failures, which by definition under the regulations do not involve the release of gas, are also shown (with transparent colorband), and represent conditions which are discovered and acted upon prior to their potentially turning into an Incident or Leak.


Incident      |      Leak      |      Failure
Mouseover for Term Definitions

Chart showing number of incidents, leaks, and failures by year


Figure 5

Incidents represent the more serious of the two types of events involving a release of gas. Nearly half of all incidents occurring in HCAs are due to Third Party Damage. Equipment-related events account for nearly 1 in 5 of these types of events and are a distant second, followed by Incorrect Operations and Construction-related events, which each account for 1 in 10 of these events.

Chart showing incidents


Figure 6

Leaks are the less serious of the two types of events involving a release of gas. Just over half of these typically smaller releases occurring in HCAs are due to Equipment-related events, with External Corrosion the second most prevalent, accounting for 1 in 5 of these events.

Chart showing leaks


Figure 7

By definition (see below), Failures do not involve a release of gas from the pipeline facility. Third Party Damage Failures occurring in HCAs account for 1 in 3 Failures; External Corrosion 1 in 4; and Equipment-related Failures less than 1 in 6.

Chart showing failures


Some additional information about the use of this web-link:

The Summary Tab provides you with the ability, by clicking on the appropriate highlighted data selection to view:

  • All operators submitting performance measure reports
  • Reports of operators with high consequence areas
  • Reports of operators with no HCAs at this time   

The Details Tab gives summary information broken down by the number of operator reports submitted for a defined range of operating parameters.  Information available under this tab encompasses:

  • Total pipeline miles;
  • Total miles of pipeline inspected which includes pipe that was inspected outside of HCAs coincident to performing the inspection of pipe within the HCAs;
  • The number of HCA miles; and the number of HCA miles inspected.
  • The "Details Tab" also provides information regarding the number of completed repairs and the number of leaks, failures and incidents classified by their cause.

The Reports Tab is a drill down feature that is activated by clicking on the highlighted number of reports for any given range under the Detail Tab.  This displays a list of pipeline operators that make up the reports in the given range.  You can view an individual operator’s report by again clicking on the highlighted report number for that individual operator.

Please note that an individual operator can file a report covering several operating systems resulting in the number of operators covered by reports being larger than the number of operators submitting reports.  The related operators for these reports are identified when you drill down to an individual report.  

Visit the Gas Integrity Management Performance Measure Reports feature now.

Definitions:

Failure
a general term used to imply that a part in service: has become completely inoperable; is still operable but is incapable of satisfactorily performing its intended function; or has deteriorated seriously, to the point that it has become unreliable or unsafe for continued use. If an event involves the unintentional release of gas, it should be reported as an incident or leak.

Immediate Repair
Immediate Repair is defined by 49 CFR 192.933(d)(1)

Incident
an event meeting the criteria in the definition in 49 CFR 191.3: An event that involves a release of gas from a pipeline and (i) A death, or personal injury necessitating in-patient hospitalization; or (ii) Estimated property damage, including cost of gas lost, of the operator or others, or both, of $50,000 or more, or An event that is significant, in the judgment of the operator, even though it did not meet the criteria above. HCA means High Consequence Area, as defined in 49 CFR 192.903.

Leak
an unintentional escape of gas from the pipeline. This would include any unintentional release of gas from a pipeline that does not result in an injury, death, or $50,000 in property damage.

Scheduled Repair
a repair scheduled in accordance with ASME 31.8S, Section 7, Figure 4 as required by 192.933(c) and One-year conditions as identified under 192.933(d)(2) as they are also required to be prioritized for repair according to a schedule. This results in all repairs required by the rule except for immediate repairs being accounted for under the "Scheduled Repairs" category of the "Performance Measure Reports.