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Pipeline Safety: Petition for Waiver; TransCanada Pipelines Limited

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Information about this document as published in the Federal Register.

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Pipeline and Hazardous Materials Safety Administration (PHMSA), Department of Transportation (DOT).


Notice; petition for waiver.


TransCanada Pipelines Limited, operator of the Portland Natural Gas Transmission System (PNGTS), requests a waiver of compliance from PHMSA regulations for selected gas transmission pipeline segments in Windham, Maine. These Start Printed Page 52872regulations require pipeline operators to confirm or revise the maximum allowable operating pressure (MAOP) of a pipeline after a class location change.


Persons interested in submitting written comments on the waiver proposed in this notice must do so by October 10, 2006. Comments filed late will be considered as practicable.


You may submit written comments by mailing or delivering an original and two copies to the Dockets Facility, U.S. Department of Transportation, Room PL-401, 400 Seventh Street, SW., Washington, DC 20590-0001. The dockets facility is open from 10 a.m. to 5 p.m., Monday through Friday, except on Federal holidays when the facility is closed. Alternatively, you may submit written comments to the docket electronically at the following Web address:

All written comments should identify the docket and notice number stated in the heading of this notice. Anyone who wants confirmation of mailed comments must include a self-addressed stamped postcard. To file written comments electronically, after logging on to, click on “Comment/Submissions.” You can also read comments and other material in the docket at General information about our pipeline safety program is available at

Anyone is able to search the electronic form of all comments received in any of our dockets by the name of the individual submitting the comment (or signing the comment, if submitted on behalf of an association, business, labor union, etc.). You may review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477) or you may visit

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James Reynolds by phone at 202-366-2786, by fax at 202-366-4566, by mail at DOT, PHMSA, 400 Seventh Street, SW., Room 2103, Washington, DC, 20590, or by e-mail at

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PNGTS requests a waiver from compliance with 49 CFR 192.611 for selected gas transmission pipeline segments in Windham, Maine. Specifically, PNGTS requests a waiver from the requirement to revise the MAOP or upgrade the pipeline segments after a class location change. If this waiver is granted, PNGTS will conduct risk control activities that include: (1) Internal pipeline inspection using geometry and magnetic flux leakage in-line inspection tools; (2) annual close interval cathodic protection surveys; (3) direct current voltage gradient (DCVG) surveys; (4) direct assessment on anomalies; (5) additional aerial patrols; and (6) installation of buried excavation warning tape over the pipeline. PNGTS asserts that these alternative risk control activities will provide an equal or higher level of safety than currently provided by the pipeline safety regulations.

Federal pipeline safety regulations at § 192.611 require a gas pipeline operator to confirm or revise the MAOP of its pipeline if the hoop stress corresponding to the established MAOP of a segment of pipeline is not commensurate with the present class location and the segment is in satisfactory physical condition.

PNGTS's waiver request involves two locations on its 24-inch pipeline in Windham, Maine. Both locations were hydrotested to 1846 pounds per square inch gauge (psig) in December of 1998:

Location 1: Consists of 785 feet of Class 1 pipe, 24-inch outside diameter, 0.343-inch wall, American Petroleum Institute (API) 5L/Grade X70 steel pipe, and 2128 feet of Class 3 pipe, 24-inch outside diameter, 0.494-inch wall, API 5L/Grade X70 steel pipe, for a total length of 2913 feet of pipe.

Location 2: Consists of 4766 feet of Class 1 pipe, 24-inch outside diameter, 0.343-inch wall, and API 5L/Grade X70 steel pipe.

With regard to location 1, PNGTS requests this waiver because the development or conversion of an active gravel pit in an industrial park will change the 785 feet of Class 1 to Class 3 pipe. With regard to location 2, PNGTS requests the waiver because the development of a residential subdivision is expected to change the entire 4766 feet of Class 1 to Class 3 pipe. Therefore, both locations will change from Class 1 to Class 3. The pipelines were constructed during 1998 and 1999 and began operating on March 10, 1999; according to PNGTS, these pipelines are in excellent condition.

PNGTS performs an annual close interval survey (CIS) on 15% to 20% of its pipeline system and in the summer of 2000, PNGTS performed a base line CIS of its entire pipeline system. This CIS revealed zero low potentials or anomalies at the requested waiver locations. PNGTS also performed a baseline high-resolution magnetic flux leakage internal inspection (smart pig) on its mainline in November of 2002. Two minor anomalies were identified during the inspection and were later excavated and investigated during the summer of 2005.

PNGTS's mainline valves (MLV) are equipped with remote controlled valve actuators. Each valve assembly contains an upstream and downstream pressure transmitter that communicates with PNGTS's supervisory control and data acquisition (SCADA) system and Gas Control Center. The primary communication method is through a satellite link with a backup modem system. If PNGTS's SCADA system detects operating pressures outside the pre-established pressure limits, the system activates an alarm which notifies the gas control operator. The gas control operator has the capability of operating the MLV remotely or isolating the pipeline completely.

PNGTS proposes to perform alternative risk control activities rather than lowering the MAOP of the system or replacing the two segments of Class 1 pipe (totaling 5551 feet). PNGTS believes that the following alternative risk control activities are consistent with pipeline safety and will maintain or exceed the margin of safety and environmental protection provided by 49 CFR § 192.611:

1. Perform a cathodic protection CIS on the requested waiver segments. The cathodic protection CIS will be performed annually and include 1000 feet upstream and downstream of the requested waiver segments.

2. Perform a DCVG survey on the requested waiver segments of the pipeline. PNGTS proposes to include an additional 1000 feet of pipeline in its survey. The additional 1000 feet of pipeline is located upstream and downstream of the requested waiver segments.

3. Perform a direct assessment on all anomalies or corrosion indications identified by the internal inspection survey or the cathodic protection CIS. The direct assessment will be performed on the requested waiver segments regardless of size or depth of anomaly indication, and include an additional 1000 feet of pipe upstream and downstream of the requested waiver segments.

4. Perform weekly aerial patrols over the entire PNGTS 24-inch mainline and 12-inch lateral pipeline. Aerial patrols will also observe pipeline surface conditions for indications of construction activity that could affect the safe operation of the pipeline. In addition, and at a minimum, PNGTS will also perform quarterly road crossing patrols and leak surveys using leak detection equipment at all road crossings located within the requested waiver segments and all corresponding Start Printed Page 52873Class 3 locations over the entire length of the requested waiver segments.

5. Install buried excavation warning tape over the pipelines, and throughout the entire requested waiver segments, to further alert excavators of the existence of PNGTS's pipelines.

Finally, PNGTS believes the additional cathodic protection CIS will insure the integrity of the cathodic protection and fusion bond epoxy coating systems, thereby minimizing the risk of future corrosion and maximizing the opportunity for prompt identification of corrosion-related deficiencies.

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Authority: 49 U.S.C. 60118(c) and 2015; and 49 CFR 1.53.

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Issued in Washington, DC on August 30, 2006.

Jeffrey D. Wiese,

Acting Deputy Associate Administrator for Pipeline Safety.

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[FR Doc. E6-14826 Filed 9-6-06; 8:45 am]