E6-3833. Pipeline Safety: Grant of Waiver; Duke Energy Gas Transmission Company

AGENCY:

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

ACTION:

Notice; Grant of Waiver.

SUMMARY:

Duke Energy Gas Transmission Company (DEGT) petitioned the Pipeline and Hazardous Materials Safety Administration (PHMSA) for a waiver of compliance with 49 CFR 192.611, which requires natural gas pipeline operators to confirm or revise the maximum allowable operating pressure of a pipeline after a change in class location. DEGT requested the waiver for certain segments of its natural gas pipeline located in Tennessee and Kentucky that have changed, and for segments that may change from Class 1 to Class 2 in the future. Under the pipeline safety regulations, class location indicates the population density near a pipeline. As the population along a pipeline increases, the class location increases. DEGT proposed to conduct a set of alternative risk control activities, in lieu of pipe replacement or pressure reduction, on all the segments requested in the waiver.

SUPPLEMENTARY INFORMATION:

Background

In accordance with 49 U.S.C. 60126, PHMSA established the Risk Management Demonstration Program (RMDP) in partnership with operators of natural gas and hazardous liquid pipeline facilities. The RMDP determines how risk management principles can be used to compliment and improve the existing Federal pipeline safety regulatory process. Under the RMDP, pipeline operators proposed risk management projects to demonstrate how a structured and formalized risk management process could enable a company to customize its safety program to allocate resources for its pipeline's particular risks, which would lead to an enhanced level of safety and environmental protection. DEGT and 11 other pipeline companies were selected as potential candidates for RMDP projects.^[1] In evaluating DEGT as a RMDP candidate, PHMSA and DEGT engaged in a consultation process in which DEGT's safety practices and pipeline risk management program were scrutinized. During this consultation process, DEGT identified 21 sites where the class location had changed from Class 1 to Class 2 along the pipeline route of 2 compressor station discharges—1 located in Tennessee and the other in Kentucky. These segments include DEGT's 3 parallel natural gas pipelines, Lines 10, 15, and 25, which are part of its Texas Eastern Pipeline System.

While awaiting approval of its risk demonstration project, on October 5, 2000, DEGT requested a waiver of compliance from 49 CFR 192.611, for the 15 pipe segments located in Tennessee that had changed from Class 1 to Class 2. The Federal pipeline safety regulations at § 192.609 require a gas pipeline operator to complete a class location change study whenever they believe an increase in population density may have caused a change in class location as defined in § 192.5. If a new class location is confirmed, the operator is required to either reduce pressure or replace the pipe in compliance with § 192.611.

Section 192.5(a)(1) defines a “class location unit” as an onshore area extending 220 yards (200 meters) on either side of the centerline of any continuous one mile length of pipeline. The class location for any unit is determined according to the following criteria in § 192.5(b):

Class 1—an offshore area or 10 or fewer buildings intended for human occupancy;

Class 2—more than 10 but less than 46 buildings intended for human occupancy;

Class 3—46 or more buildings intended for human occupancy, or areas where a pipeline lies within 100 yards (91 meters) of either a building or a small, well-defined outside area (such as a playground, recreation area, outdoor theater, or other place of public assembly) that is occupied by 20 or more persons on at least 5 days a week for 10 weeks in any 12-month period;

Class 4—buildings with four or more stories above ground are prevalent (e.g, large office buildings).

Pipeline safety regulations impose more stringent design and operation requirements as the class location increases. When a class location changes to a higher class (e.g., from Class 1 to Class 2), § 192.611 requires the operator to reduce the pressure on the pipeline to provide an additional margin of safety. The operator may be able to avoid the pressure reduction if a pressure test on the pipe confirms that the prescribed safety margin exists. If a previous pressure test has not confirmed the prescribed safety margin, the operator must test the pipe to confirm the margin, reduce the pressure, or replace the pipe with new pipe. DEGT proposed to conduct alternative risk control activities in lieu of compliance with § 192.611 and asserted that the alternative risk control activities would provide a level of safety equivalent to that required by § 192.611.

On December 11, 2000, PHMSA published a notice in the Federal Register seeking comments on its intent to grant DEGT the waiver (65 FR 77419); no comments were received. On March 9, 2001, PHMSA granted and published the waiver for the 15 pipe segments in Tennessee (66 FR 14256).

On June 1, 2004, DEGT submitted a second petition for waiver of § 192.611. DEGT requested the waiver apply to the 21 pipe segments located in Tennessee and Kentucky that changed from Class 1 to Class 2 and to segments that may change from Class 1 to Class 2 in the future. These were the segments initially identified for DEGT's Risk Demonstration project, including the 15 segments on which PHMSA had granted the waiver in March 2001. DEGT also requested the waiver apply to all pipeline segments that may, in the future, change from Class 1 to Class 2. These pipeline segments are found at DEGT's Mt. Pleasant, Tennessee compressor station discharge, Gladeville compressor station, and the pipeline segments between its Owingsville, Kentucky compressor station discharge and Wheelersburg compressor station.

On August 16, 2004, PHMSA published a notice in the Federal Register requesting public comments on DEGT's June 1, 2004 request for waiver (69 FR 50438); PHMSA did not receive any comments.

DEGT's Waiver Request

DEGT's waiver request involves 3 parallel pipelines in its Texas Eastern Pipeline System, Lines 10, 15, and 25: (1) 3 line segments running downstream of its Mt. Pleasant, Tennessee compressor station discharge to its Gladeville compressor station, each approximately 63.6 miles; and (2) 3 line segments running downstream of its Owingsville, Kentucky compressor station discharge to its Wheelersburg compressor station, each approximately 60.5 miles (collectively, the “waiver sites”).

Within the waiver sites are 21 pipe segments (identified in the following table) that have changed from Class 1 to Class 2:

	County & State	Line number	Begin milepost	End milepost
Mt. Pleasant Station Discharge:
Site #1	Maury Co., Tennessee	10 15 25	226.88 226.90 227.05	227.35 227.50 227.50
Site #2	Maury Co., Tennessee	10 15 25	228.49 228.65 228.63	229.07 229.21 229.22
Site #3	Maury Co., Tennessee	10 15 25	238.01 238.17 238.17	239.19 239.34 239.36
Site #3A	Maury Co., Tennessee	25	241.69	241.72
Site #4	Maury Co., Tennessee	10 15 25	247.79 247.94 247.94	247.88 248.04 248.03
Site #5	Williamson Co., Tennessee	10 15 25	264.03 264.19 264.24	265.31 265.49 265.48
Owingsville Station Discharge:
Site #6	Fleming Co., Kentucky	10 25	514.78 515.25	514.98 515.28
Site #7	Lewis Co., Kentucky	10 15 25	531.10 531.54 531.54	533.33 533.75 533.76

DEGT requested that the waiver granted on March 9, 2001 for the 15 segments be extended to include the 6 segments in Kentucky that have changed from Class 1 to Class 2. This request would include the segments within both the Mt. Pleasant compressor station discharge and the Owingsville compressor station discharge that may change from Class 1 to Class 2 in the future.

DEGT has implemented the alternative risk control activities that were outlined in the waiver issued on March 9, 2001. DEGT noted that it has also implemented the following risk control activities on the above identified 15 segments in Tennessee and the six segments in Kentucky:

• Conducted internal inspections on the entire length of the waiver segments using geometry and magnetic flux leakage in-line inspection tools. These tools were used to identify indications of wall loss (e.g., corrosion), as well as dents and gouges from initial construction damage or damage from third party excavators working along the pipeline right-of-way. The internal inspection included Lines 10, 15, and 25 in the Mt. Pleasant compressor station discharge covering approximately 190 miles of pipe, and Lines 10, 15, and 25 in the Owingsville compressor station discharge covering approximately 185 miles of pipe. The results of the inspection were provided to PHMSA's Southern Region.
• Repaired indications of corrosion, existing construction damage, and existing outside force damage identified by the internal inspection tools using conservative investigation and repair criteria.
• Hydrostatically tested portions of Line 10 that previously had not been tested to 100 percent of the specified minimum yield strength. This includes 2 sites in Tennessee (2.5 miles northwest of Rally Hill in Maury County and 3.5 miles east-northeast of Arrington in Williamson County) and 1 site in Kentucky (4.4 miles southeast of Kinniconick in Lewis County). The results of the inspection were provided to PHMSA's Southern Region.
• Performed enhanced third-party damage prevention activities. This included installation, for a one-year trial period, of a TransWave monitoring system on the full length of pipeline within the Mt. Pleasant discharge (63.6 miles on each line). The TransWave system was used to monitor the change in waveform of small currents that may be caused by disturbances created by excavation or other third-party activities. The TransWave system was employed to determine its reliability and usefulness at detecting third-party encroachments (construction, excavation, etc.) in the pipeline right-of-way. At the conclusion of the one-year trial period, DEGT submitted the final test results to PHMSA's Southern Region.

PHMSA has determined that these activities provide an equivalent level of protection and safety as that provided by 49 CFR § 192.611.

Grant of Waiver

In light of the aforementioned, PHMSA finds that granting DEGT a waiver from complying with 49 CFR 192.611 for the entire 21 pipeline segments located along certain segments of its natural gas pipeline in Tennessee and Kentucky that have changed from Class 1 to Class 2 and for those segments that may change from Class 1 to Class 2 in the future, is not inconsistent with pipeline safety regulations. The alternative activities DEGT conducted on the 21 segments where a class location change occurred provides an equivalent level of safety and protection to that provided by the regulations at 49 CFR 192.611. The actions required by this waiver for future class location sites will also provide equivalent safety and protection. The grant of this waiver will conclude all PHMSA action on DEGT's projects under the RMDP.

Under 49 CFR 192.611, PHMSA grants DEGT's request for a waiver for the 21 segments on Lines 10, 15, and 25 within its Mt. Pleasant, Tennessee compressor station discharge to its Gladeville compressor station discharge and within its Owingsville, Kentucky compressor station discharge to its Wheelersburg compressor station discharge that has changed from Class 1 to Class 2. This waiver supersedes the waiver granted on March 9, 2001.

PHMSA further grants DEGT's request for waiver of the requirements of 49 CFR 192.611 for the segments on Lines 10, 15, and 25 within its Mt. Pleasant, Tennessee compressor station discharge to its Gladeville compressor station discharge and within its Owingsville, Kentucky compressor station discharge to its Wheelersburg compressor station discharge that may change from Class 1 to Class 2 in the future.

This waiver may change certain line segments from Class 1 to Class 2. This will be contingent upon DEGT providing information and notification to PHMSA, and PHMSA not objecting to including the line segments. DEGT will not be allowed to apply the waiver to any site that PHMSA objects to.

Should DEGT fail to comply with any terms of the waiver, or should PHMSA determine that the terms of this waiver are no longer appropriate or that the waiver is inconsistent with pipeline safety, PHMSA may revoke this waiver and require DEGT to comply with the regulatory requirements of 49 CFR 192.611 and any other applicable regulations.

This waiver is granted on the condition that DEGT complies with the following requirements:

1. DEGT must meet the technical criteria of the PHMSA Class Change Waiver Protocol or other criteria for class location waivers that PHMSA may adopt for any future class change sites within the waiver segments that change from Class 1 to Class 2.

2. DEGT must provide prior notice to PHMSA's Southern Region of its intent to rely on this waiver, rather than replace pipe, in any future class change sites along the waiver segments so that PHMSA can independently verify that the criteria have been met. This notice must include a schedule of any remedial measures to be performed in future waiver sites. PHMSA may request additional information or clarification before allowing DEGT to apply the waiver to any future site. DEGT may proceed with the waiver on the future site unless PHMSA objects.

3. DEGT must conduct additional public information activities in the populated areas along all waiver segments. This should include providing information to local emergency response personnel/agencies about the operation of the pipeline, the possibility of accidents, and actions that must be taken in the event of an accident on the pipeline.

4. DEGT must conduct future inspections of the waiver segments and remediate any defects identified in the waiver segments in accordance with subpart O of 49 CFR part 192.

5. Subsequent in-line inspections for the waiver sites must be scheduled in accordance with 49 CFR part 192, subpart O.

6. The waiver sites must be in compliance with American Society of Mechanical Engineer's standard B31.8S criteria for stress corrosion cracking site identification and site investigation/testing.

7. DEGT must provide the PHMSA's Southern Region with sufficient advance notice to enable PHMSA staff to attend and participate in all significant risk assessment activities involving the waiver segments.

8. Within the three months following approval of this waiver and annually thereafter, DEGT is required to report the following information to PHMSA's Southern Region:

• The economic benefit to the company. This should address both the costs avoided from not replacing the pipe, and the added costs of the inspection program (required for the initial report only).
• In the first annual report, fully describe how the public benefits from energy availability. Should address the benefits of avoided disruptions as a consequence of pipe replacement and the benefits of maintaining system capacity. Subsequent reports must indicate any changes to this initial assessment.
• The results of any in-line inspections or direct assessments performed during the previous year within the inspection area containing the waiver location(s).
• Any new integrity threats identified during the previous year within the inspection area containing the waiver location(s).
• Any encroachment of the inspection area including the waiver location(s) and new residences (by number) or areas of public congregation.
• Any incidents (both reportable and non reportable) that occurred during the previous year associated with the inspection area containing the waiver location(s).
• Any leaks on the pipeline (both reportable and non reportable) that occurred during the previous year in the inspection area containing the waiver location(s).
• All repairs on the pipeline made during the previous year in the inspection area containing the waiver location(s).
• On-going damage prevention initiatives on the pipeline in the inspection area containing the waiver location(s) and a discussion on their success.
• Any mergers, acquisitions, transfers of assets, or other events affecting the regulatory responsibility of the company operating the pipeline to which the waiver applies.

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

Issued in Washington, DC, on March 13, 2006.

Joy Kadnar,

Director for Engineering and Engineering Support.

Footnotes

1.  “Candidates for the Pipeline Risk Management Demonstration Program” (62 FR 143; July 25, 1997); “Pipeline Safety: Remaining Candidates for the Pipeline Risk Management Demonstration Program” (62 FR 197; October 10, 1997).