Pipeline Safety: Request for Waiver; GulfTerra Field Services LLC

AGENCY:

Research and Special Programs Administration (RSPA); U.S. Department of Transportation (DOT).

ACTION:

Notice of intent to consider waiver request.

SUMMARY:

GulfTerra Field Services LLC (GTFS), requested a waiver of compliance with the regulatory requirements at 49 CFR 192.619(a)(2)(ii), 192.503, and 192.505 for certain offshore pipeline segments of the deepwater Phoenix Gas Gathering System (Phoenix). GTFS is requesting a waiver from the post-construction hydrotesting requirement for selected segments of the Phoenix system.

DATES:

Persons interested in submitting written comments on the waiver request described in this Notice must do so by April 28, 2004. Late filed comments will be considered as far as practicable.

ADDRESSES:

You may submit written comments by mailing or delivering an original and two copies to the Dockets Facility, U.S. Department of Transportation (DOT), 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: http://dms.dot.gov.

All written comments should identify the docket and notice numbers 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 http://dms.dot.gov,, click on “Comment/Submissions.” You can also read comments and other material in the docket. General information about the Federal pipeline safety program is available at http://ops.dot.gov.

Anyone is able to search the electronic form of all comments received into 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 (Volume 65, Number 70; Pages 19477-78) or you may visit http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:

James Reynolds by telephone at 202-366-2786, by fax at 202-366-4566, by mail at DOT, Research and Special Programs Administration (RSPA) Office of Pipeline Safety (OPS), 400 7th Street, SW., Washington, DC 20590, or by e-mail at james.reynolds@rspa.dot.gov.

SUPPLEMENTARY INFORMATION:

Background

GTFS, a wholly owned subsidiary of GulfTerra Energy Partners L.P., has entered into a gas gathering agreement with Kerr McGee Oil & Gas Corporation and the Devon Louisiana Corporation to design, build, own, and operate the Phoenix Gas Gathering System (Phoenix). GTFS will transport natural gas from the Red Hawk Spar, a deepwater production facility, to the Pioneer Platform, an existing downstream pipeline facility.

System Description

The GTFS pipeline will extend 76 miles through Federal waters on the Gulf of Mexico Outer Continental Shelf (OCS) and will cross one shipping channel, known as a “fairway.” The pipeline will include a subsea ‘wye’ and a subsea ‘tee’ for future interconnections to other pipelines. The planned maximum allowable operating pressure (MAOP) of this pipeline and the associated platform facilities is 2,875 pounds per square inch gauge (psig). The system will normally operate at pressures up to 2,500 psig.

The Phoenix system will consist of the following primary components, in order of occurrence from deep to shallow water:

1. A steel catenary riser (SCR) consisting of 16-inch outside diameter (O.D.) × 1.00-inch wall thickness (w.t.), API 5L X65 seamless pipe, on the Red Hawk Spar at a depth of 5,300 feet. The SCR will be coated with triple-layer polypropylene at the touchdown point and 14 to 16 mils of thin film fusion bonded epoxy (FBE) and 2 to 3 mils of rough coat FBE through the midsection. There will be 23 mils of thin film FBE in the vortex induced vibration (VIV) suppression strake section, and a 1-inch thick sleeve of Splashtron coating in the pull-tube;

2. A 76-mile pipeline from the Red Hawk platform to the Vermilion riser (VR). Beginning at the deepwater end, approximately 40 miles of pipe will be 18-inch O.D. × 0.791-inch w.t., API 5L X65 double submerged arch weld (DSAW) pipe, followed by approximately 36 miles of 18-inch O.D. × 750-inch w.t., API 5L DSAW pipe. All joints will be coated with 14 to 16 mils of thin film FBE with an additional 2 to 3 mils of FBE rough coating;

3. An 18-inch diverless, piggable ‘wye’ assembly downstream of the Red Hawk Spar in Garden Banks to accommodate future connection(s) to the pipeline;

4. An 18-inch O.D. × 16-inch diverless ‘tee’ assembly in Garden Banks to accommodate future connection(s) to the pipeline; and

5. Pipeline support facilities located on the VR 397 “A” platform, including a pig receiver and related piping and safety controls. The platform riser will be 18-inch O.D. × 0.875-inch w.t., API 5L X60 DSAW pipe coated with 14 to 16 mils of thin film FBE. In the wave (splash zone) area, the riser pipe will be protected with a 1/2-inch thick sleeve of Splashtron coating.

Need for Hydrotest

GTFS contends it is unnecessary to hydrostatically test this pipeline. GTFS asserts that a hydrostatic test will not demonstrate the strength and integrity of the pipeline because the pipeline is designed of heavier wall pipe and it will never experience the wall stress intended to be produced by a hydrotest. The heavier wall pipe is used to prevent the collapse of the pipeline in the face of the huge external pressures exerted on it at a water depth of 5,300 feet.

Proposed Alternative Risk Control Activities

GTFS proposes the following alternative risk control activities to provide a margin of safety and environmental protection comparable to that required by the pressure-test regulations:

1. Utilize thick wall, high strength, and high quality DSAW pipe;

2. Perform a pipe mill hydrotest on each length of fabricated pipe equivalent to 95% specified minimum yield strength (SMYS) to detect defects in the seam weld and prevent the deployment of defective pipe joints;

3. Perform extensive inspection and quality control during the line pipe manufacture, transport, fabrication, and installation to prevent pipe damage;

4. Utilize Automated Ultrasonic Inspection (AUT) for inspection of offshore welds to improve defect detection in the girth weld and to improve the weld quality during the pipeline and SCR fabrication;

5. Subject all buckle arrestors to complete radiographic and magnetic particle inspection, including radiographic inspection of all buckle arrestor to line pipe welds;

6. Perform complete radiographic inspection and hydrotesting of all welds connecting subsea valves and assemblies to the pipeline;

7. Perform a leak test of the pipeline's subsea tie-in flange that connects to the VR 397 riser flange; and

8. Perform factory acceptance hydrotests of all subsea ‘wye’, ‘tee’, ball valve, and check valve assemblies.

Intent To Consider Waiver

Although performing an in situ hydrotest on this pipeline would comply with the plain language of the regulation, GTFS believes the intent of the regulations cannot be met by hydrostatic testing. Due to the heavier wall thickness requirements and external hydrostatic pressures in deep water, the traditional pipeline hydrostatic test generates stresses as a percentage of SMYS that are well below those typically experienced in a pipeline test. GTFS asserts that the hydrostatic test cannot demonstrate the strength or integrity of the system.

Therefore, RSPA/OPS will consider whether a hydrotest of this pipeline is necessary and whether the alternative risk control activities proposed by GTFS will yield an equivalent or greater degree of safety. This Notice is RSPA/OPS' only request for public comment before making its final decision in this matter. After considering any comments, RSPA/OPS will make a final determination to grant or deny the waiver as proposed or with modifications and conditions. If the waiver is granted and RSPA /OPS subsequently determines that the effect of the waiver is inconsistent with pipeline safety, RSPA/OPS may revoke the waiver at its sole discretion.