[Federal Register Volume 64, Number 102 (Thursday, May 27, 1999)]
[Notices]
[Pages 28867-28868]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-13448]
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DEPARTMENT OF TRANSPORTATION
Research and Special Programs Administration
[Docket No. RSPA-99-5442; Notice 1]
Chevron Pipe Line Company; Petition for Waiver
AGENCY: Research and Special Programs Administration, DOT.
ACTION: Notice.
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SUMMARY: Chevron Pipe Line Company (CPL) has petitioned the Research
and Special Programs Administration for a waiver from compliance with
49 CFR 19.612(b)(3), which requires that gas pipeline facilities in the
Gulf of Mexico found to be exposed on the seabed or constituting a
hazard to navigation be reburied so that the top of the pipe is 36
inches below the seabed for normal excavation or 18 inches for rock
excavation.
DATES: Comments must be received on or before June 28, 1999.
ADDRESSES: Comments should identify the docket number of this notice,
RSPA-99-5442; Notice 1, and be mailed to the Dockets Facility, U.S.
Department of Transportation, 400 Seventh Street, SW, Plaza 401,
Washington, DC 20590-0001. You should submit the original and one copy.
If you wish to receive confirmation of receipt of your comments, you
must include a stamped, self-addressed postcard. All comments and
docket material may be viewed in the Dockets Facility. You may contact
the Dockets Facility at (800) 647-5527, for copies of this notice or
other material that is referenced herein. The Dockets Facility is open
from 10:00 a.m. to 5:00 p.m., Monday through Friday, except on Federal
holidays. You may submit comments to the docket electronically. To do
so, log on to their Web Site: http://dms.dot.gov. Click on Help &
Information to obtain instructions for filing a document
electronically.
FOR FURTHER INFORMATION CONTACT: L.E. Herrick by telephone at 202-366-
5523, by fax at 202-366-4566, by mail at U.S. Department of
Transportation, RSPA, DPS-10, 400 Seventh Street, SW, Washington, DC
20590, or via e-mail to le.herrick@rspa.dot.gov regarding the subject
matter of this notice.
SUPPLEMENTARY INFORMATION:
Background
On October 10, 1998, Chevron Pipeline Company (CPL) performed a
shallow water, side-scan sonar survey of the various pipelines within
the path of Hurricane Georges. The survey revealed exposed sections on
both the 16-inch and 12-inch pipelines of the Chandeleur Block 15 (east
of the Chandeleur Islands). Approximately 1400 feet of the 16-inch
pipeline and 1300 feet of the 12-inch pipeline was exposed in shallow
waters as the distance increased from the islands. The sea bottom
material in this area is sugar sand with shoal like conditions.
CPL Marked the exposed pipe in accordance with 49 CFR 192.612 and
33 CFR 64. Another survey of the exposed pipelines was performed on
January 17, 1999, to determine if natural spoil was building at these
areas and to determine if other areas that were closer to the islands
had become exposed. Upon receipt of the new data, CPL discovered that
some exposed areas had gained natural cover, while other areas had lost
cover. Another 450 foot section of the 16-inch pipeline was found to be
exposed in shallow water close to the islands.
Regulatory Requirements
After an exposed pipeline has been discovered, the owner must
clearly mark the pipeline in accordance with 49 CFR 192.612. The
operator has six months to cover the pipeline so that the top of the
pipe is 36 inches below the seabed for normal excavation or 18 inches
for rock excavation. The exposed CPL pipelines are required to have 36
inches of cover.
CPL stated reasons for not covering the pipeline with natural cover
to comply with 192.612(b)(3):
(1) The exposed pipelines are high pressure gas lines (normal
operating pressure of 650-700 psi.) connecting Chevron's Main Pass 41
and Mobile Bay gas fields with the Chevron Pascagoula refinery. These
pipelines are the main source of fuel gas for the refinery, as being
the only outlet for natural gas produced on the various offshore
platforms. When performing burial and line lowering operations, CPL's
safety programs specifies that the pressure must be lowered to less
than 150 psi in the pipeline. This is necessary for safe placement of
the jetting sled equipment on the exposed pipelines and for safe
[[Page 28868]]
reburial of the exposed pipelines. CPL asserts that the required
pressure reduction is not feasible because the refinery and natural gas
wells would have to be closed down during the jetting operations.
(2) In addition, the mechanical jet sled must be towed across the
pipeline. The vessels used to tow the sled have a greater draft than
the water depth in the shallower exposure areas. Uncertain wind and sea
conditions could shut down the jetting operation and result in
uncontrollable delays.
(3) In order to safely lower the exposed sections of line, bottom
material will be disturbed well beyond the actual exposed area of the
pipeline in a lateral direction to avoid subjecting the pipe to
abnormal stress. Because the vessels used to tow the mechanical jet
sled draft more water than is available in much of this area, there
could be adverse environmental impact to the surrounding area.
Request for Waiver
CPL has proposed to install concrete mesh blanket units to protect
the pipeline from damage in lieu of the 36 inches of cover required by
[192.612(b)(3)]. Each concrete mesh blanket unit is a 20-foot by 8-foot
by 9-inch section constructed from 160 individually cast 17-inch by 17-
inch by 9-inch beveled concrete briquettes inter-connected with \3/4\-
inch polypropylene UV stabilized line.
We propose to grant the waiver with the provision that CPL also
install a rock shield over the pipeline before installation of the
blanket. The rock shield must be of at least 3/8-inches of thickness
constructed of an appropriate material. With the addition of the rock
shield we believe there is no reason to anticipate a lesser level of
safety than would be achieved by a 36-inch pipeline burial. With these
conditions, it appears that the requested waiver of compliance with
192.612(c)(3) would not be inconsistent with pipeline safety. We
propose to grant the waiver. Interested parties are invited to comment
on the proposed waiver by submitting, in duplicate, data, views, or
arguments relevant to the proposed grant of waiver. We specifically
request comments on the adequacy of the proposed concrete mat to reduce
the hazard to navigation posed by the exposed pipeline and on any
impact the mat may have on fishing vessel operations. Comments should
identify the Docket and Notice numbers, and be submitted to the Dockets
Facility, U.S. Department of Transportation, 400 Seventh Street, SW,
Plaza 401, Washington, DC 20590-0001.
All comments received on or before, June 28, 1999 will be
considered before final action is taken. Late filed comments will be
considered so far as practicable. No public hearing is contemplated,
but one may be held at a time and place to be set in a Notice in the
Federal Register if requested by an interested person desiring to
comment at a public hearing and raising a genuine issue.
(Authority: 49 U.S.C. 60118(c); 49 CFR 1.53)
Issued in Washington, DC, May 21, 1999.
Richard B. Felder,
Associate Administrator for Pipeline Safety.
[FR Doc. 99-13448 Filed 5-26-99; 8:45 am]
BILLING CODE 4910-60-P
