[Federal Register: April 6, 2005 (Volume 70, Number 65)]
[Notices]
[Page 17509]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr06ap05-145]
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DEPARTMENT OF TRANSPORTATION
Pipeline and Hazardous Materials Safety Administration
Pipeline Safety: Strapping Table Calibration for Pipeline
Breakout Tank Operators
AGENCY: Office of Pipeline Safety (OPS), Pipeline and Hazardous
Materials Safety Administration (PHMSA), DOT.
ACTION: Notice; issuance of advisory bulletin.
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SUMMARY: This advisory notice alerts pipeline operators of all
hazardous liquid pipeline facility systems about the need to validate
the accuracy of breakout tank strapping tables. Under certain
circumstances, strapping table errors can potentially lead to dangerous
conditions.
FOR FURTHER INFORMATION CONTACT: Joy Kadnar by phone at (202) 366-0568,
by fax at (202) 366-4566, or by e-mail, joy.kadnar@dot.gov. General
information about the Pipeline and Hazardous Materials Safety
Administration's Office of Pipeline Safety (OPS) programs may be
obtained by accessing the home page at http://ops.dot.gov.
SUPPLEMENTARY INFORMATION:
I. Background
A breakout tank exploded and subsequently ignited in Glenpool,
Oklahoma on April 7, 2003. The accident involved an 80,000-barrel
breakout tank that exploded and burned as it was being filled with
diesel. The resulting fire burned for over 20 hours and damaged two
other nearby breakout tanks. While there were no injuries or
fatalities, the cost of the accident exceeded two million dollars,
residents adjacent to the accident site were evacuated, and area
schools were closed for two days.
The National Transportation Safety Board (NTSB) conducted an
investigation into the accident and subsequently published a Pipeline
Accident Report titled ``Storage Tank Explosion and Fire in Glenpool,
Oklahoma.'' In its findings adopted on October 13, 2004, the NTSB
issued a recommendation to OPS to issue an advisory bulletin to liquid
pipeline operators to validate the accuracy of their tank strapping
tables.
The breakout tank that exploded contained an internal floating roof
system equipped with pontoons that float on top of the product at a
certain level. The tank also had legs that supported the roof whenever
the product was drained and the volume of liquid in the tank decreased
to the level at which the roof no longer floated. Additionally, the
tank had two Supervisory Control and Data Acquisition System (SCADA)
alarms to alert controllers when the volume was nearing the level at
which the roof would no longer float. The alarm set points were based
on the landed height of the floating roof assumed in the operator's
strapping table.
NTSB determined that based on the height measurement of the
floating roof documented on the construction inspection report, and
based on measurements investigators made after the accident, the
strapping table was incorrect. Specifically, the distance from the
bottom of the pontoon to the datum plate was found to be higher than
indicated on the pre-accident strapping table. The surface of the
charged diesel was within approximately two inches of the pontoons at
the time of the explosion. This, according to NTSB, is the most likely
time for a static discharge to occur. Based on this finding, as well as
other contributing factors, the NTSB determined that an incorrect
measurement on the strapping table contributed to the cause(s) of the
accident.
II. Advisory Bulletin ADB-05-02
To: Owners and Operators of All Pipeline Facilities Who Rely on
Strapping Tables to Determine Volume Based on Measured Height For
Product Level.
Subject: Validation of Strapping Tables to Reduce the Likelihood of
Errors That May Lead to Dangerous Conditions in Breakout Tanks.
Purpose: To advise owners and operators of all hazardous liquid
pipeline facilities about the need to validate strapping tables.
Advisory: Strapping Tables are commonly used to determine the
commodity volume based on product level within breakout tanks. If the
strapping table is incorrect, operators may expose themselves and the
community to unnecessary risks.
OPS seeks to advise operators that they should review and, if
necessary, revise their breakout tank operating procedures to minimize
risk. The strapping tables should be validated to reduce the potential
for errors that may lead to dangerous conditions, such as static
discharge inside a tank after a floating roof has been either
intentionally or unintentionally landed. Pipeline operators, therefore,
may need to adjust the measurements on their strapping tables to ensure
accuracy.
Issued in Washington, DC, on March 18, 2005.
Theodore L. Willke,
Deputy Associate Administrator for Pipeline Safety.
[FR Doc. 05-6729 Filed 4-5-05; 8:45 am]
BILLING CODE 4910-60-P