[Federal Register Volume 65, Number 172 (Tuesday, September 5, 2000)]
[Notices]
[Page 53803]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-22568]


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DEPARTMENT OF TRANSPORTATION

Research and Special Programs Administration


Pipeline Safety: Internal Corrosion in Gas Transmission Pipelines

AGENCY: Research and Special Programs Administration (RSPA), DOT.

ACTION: Notice; issuance of advisory bulletin.

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SUMMARY: The Office of Pipeline Safety (OPS) is issuing this bulletin 
to owners and operators of natural gas transmission pipeline systems to 
advise them to review their internal corrosion monitoring programs and 
operations. Operators should consider factors that influence the 
formation of internal corrosion, including gas quality and operating 
parameters. Operators should give special attention to pipeline 
alignment features that may contribute to internal corrosion by 
allowing condensates to settle out of the gas stream.
    This action follows a review of incidents involving internal 
corrosion, some of which resulted in loss of life, injuries, and 
significant property damage. OPS' preliminary investigation of a recent 
gas transmission pipeline incident found wall thinning on damaged pipe 
associated with the incident. The wall thinning is consistent with that 
caused by internal corrosion.

ADDRESSES: This document can be viewed at the OPS home page at: http://ops.dot.gov.

FOR FURTHER INFORMATION CONTACT: Richard Huriaux, (202) 366-4565, or by 
e-mail, [email protected].

SUPPLEMENTARY INFORMATION:

I. Background

    Internal corrosion control in gas transmission pipelines is 
addressed in the federal pipeline safety regulations at 49 CFR 192.475 
and 192.477. Internal corrosion is most often found in gas transmission 
pipelines and appurtenances in the vicinity of production and gathering 
facilities or storage fields.
    An OPS review of incident reports and inspections indicated that 
better industry guidance is needed to determine the best practices for 
monitoring the potential for internal corrosion in gas transmission 
pipelines. Some methods for monitoring internal corrosion are weight 
loss coupons, radiography, water chemistry tests, in-line inspection 
tools, and electrical, galvanic, resistance and hydrogen probes. 
Operators should refer to available recommended practices provided by 
national consensus standards organizations, such as the American 
Petroleum Institute, National Association of Corrosion Engineers, and 
Gas Piping Technology Committee (GPTC) for guidance in addressing 
internal corrosion issues.
    OPS has worked with GPTC to revise the Guide for Gas Transmission 
and Distribution Piping Systems (Guide) to better address the control 
of internal corrosion. GPTC is considering modifying the Guide to 
address design considerations, corrective measures, and detection 
techniques for internal corrosion.

II. Advisory Bulletin (ADB-00-02)

    To: Owners and Operators of Gas Transmission Pipelines.
    Subject: Internal Corrosion in Gas Transmission Pipelines.
    Purpose: To advise owners and operators of natural gas transmission 
pipelines of the need to review their internal corrosion monitoring 
programs and operations.
    Advisory: Owners and operators of natural gas transmission 
pipelines should review their internal corrosion monitoring programs 
and consider factors that influence the formation of internal 
corrosion, including gas quality and operating parameters. Operators 
should give special attention to pipeline alignment features that may 
contribute to internal corrosion by allowing condensates to settle out 
of the gas stream.
    This action follows a review of incidents involving internal 
corrosion, some of which resulted in loss of life, injuries, and 
significant property damage. OPS' preliminary investigation of a recent 
gas transmission pipeline incident found internal wall thinning on 
damaged pipe associated with the incident. The wall thinning is 
consistent with that caused by internal corrosion.
    Gas transmission owners and operators should thoroughly review 
their internal corrosion management programs and operations:
     Review procedures for testing to determine the existence 
or severity of internal corrosion associated with their pipelines. Some 
methods for monitoring internal corrosion are weight loss coupons, 
radiography, water chemistry tests, in-line inspection tools, and 
electrical, galvanic, resistance and hydrogen probes.
     Special attention should be given to specific conditions, 
including flow characteristics, pipeline location (especially drips, 
deadlegs, and sags, which are on-line segments that are not cleaned by 
pigging or other methods, fittings and/or ``stabbed'' connections which 
could affect gas flow, operating temperature and pressure, water 
content, carbon dioxide and hydrogen sulfide content, carbon dioxide 
partial pressure, presence of oxygen and/or bacteria, and sediment 
deposits.
     Review conditions in pipeline segments downstream of gas 
production and storage fields.
     Review conditions in pipeline segments with low spots, 
sharp bends, sudden diameter changes, and fittings that restrict flow 
or velocity. These features can contribute to the formation of internal 
corrosion by allowing condensates to settle out of the gas stream.

    Issued in Washington, DC, on August 29, 2000.
Stacey L. Gerard,
Associate Administrator for Pipeline Safety.
[FR Doc. 00-22568 Filed 9-1-00; 8:45 am]
BILLING CODE 4910-60-P