In This Issue

Pipeline Integrity Management in High Consequence Areas (Gas Transmission Pipelines) – Notice of public meeting

OPS will conduct a meeting the proposed gas pipeline integrity management rule on Friday, April 25, 2003, from 8 a.m. to 4 p.m. at the Marriott at Washington Dulles Airport, 4520 Aviation Drive, Dulles, VA 20166. Tel: 703-471-9500; Web site: The meeting is open to all. There is no cost to attend. You may register electronically for this meeting at: Please make your reservations as soon as possible as hotel rooms are limited. For other details on this meeting contact Juan Carlos at 202-366-1933.

At this meeting OPS intends to present the following issues for comment and to question further those offering comments to assure that they completely understand each issue. The preliminary agenda for the April meeting includes the following questions for discussion:


Low Stress Pipelines
Should assessment requirements for low-stress pipeline (i.e., operating at less than 30 percent SMYS) allow use of confirmatory direct assessment (CDA) for all assessments (baseline and reassessments)?

Pressure Testing
Should the requirement to pressure test pipelines to verify integrity against material and construction defects be limited to pipeline segments for which information suggests a potential vulnerability to such defects? If so, what information should be relied upon?

Direct Assessment Equivalency Should the assessment intervals for direct assessment be revised to be the same as those applicable to in-line inspection or pressure testing? Are there opportunities to quickly schedule and assess research demonstrations to provide additional data on which to base judgments about validity?

Plastic Transmission Lines
What assessment requirements should be applicable to plastic transmission pipelines?


Dents and Gouges
Should a repair criteria for constraint dents on the bottom of the pipe be different from that allowed for dents located on the top? Should the presence of stress risers, cracking or metal loss affect this decision?

Preventive and Mitigation Measures

Third Party Damage
Should additional third-party damage prevention methods be utilized instead of explicit assessments for third-party damage? What methods should be used in conjunction with other assessment methods to detect delayed third party damage?

Segments Outside HCAs
How can the requirements be clarified for the situations when an operator should look beyond the segment in a high consequence area, when segments outside the HCA are likely to have similar integrity concerns as those found inside an HCA?

Performance Measures
Should we require monthly electronic reporting of performance measures?


High Consequence Area-Bifurcation Option
Should a rule allow two options: following the definition of high consequence areas defined by final rule on August 6, 2002; ( 67 FR 50824 ) or using potential impact circles along the entire length of the pipeline? Under either option, an operator would calculate the potential impact circles for each segment, but the use of those circles would differ depending on the option. If the operator used the class location component of the high consequence area definition, the operator would treat entire class 3 and 4 areas as high consequence areas and use the potential impact circles to determine population density beyond 660 feet using specified number of buildings intended for human occupancy. Under the potential impact circle option, operators would use the circles to identify areas where the density of buildings intended for human occupancy exceeds a specified number and then focus the integrity assessments, repairs and other protections in these areas.

Requirements for how an operator treats identified sites that are defined in the high consequence area would not change under either option.

Population Threshold
Should the criterion for determining the population density component of a high consequence area be based on 10 or 20 buildings intended for human occupancy within the impact circle?

Impact Radius Safety Margin
Should additional safety margin be applied to the potential impact circle radius calculated using the C-FER equation?

Should a rule allow an operator to use data regarding the number of buildings within 660 feet of the pipeline (available now to operators because of the existing definition of class locations) to infer (extrapolate) the building density in potential impact circles larger than 660 feet? Should this be limited to an interim period of five years to allow operators to collect additional data on buildings beyond 660 feet?