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NACE ECDA SeminarJ. W Marriott Hotel
Steve Nanney
Project Manager
PHMSA – Engineering and
Emergency Support Section
January 26, 2009
Presentation Outline
Recent Accident and Incident Statistics
Gas and Liquid IM Programs Progress
Casings and Assessments
Recent Accident and Incident Statistics
Recent Incident Statistics
43 42 40 38
0
20
40
60
80
100
Source: DOT/PHMSA Incident Data as of Jan. 5, 2009
Pipeline Incidents Involving Death or Major Injury
1986 - 2008 (projected)
Statistical trend line on incidents
PerformanceTargets
Recent Incident Statistics
0
20
40
60
80
100
120
140
2002 2003 2004 2005 2006 2007 2008
Pipeline Incidents w/Corrosion as the Primary Cause (2002-2008)
Gas Distribution (2%)
Gas Transmission (25%)
Hazardous Liquid (73%)
Source: DOT/PHMSA Incident Data as of Jan. 5, 2009
Recent Incident Statistics
2008 Gas Transmission Incident Data
Material /Const
16%
External
Corrosion
10%
Internal
Corrosion
3%
Outside Force
(TPD)
17%Unknown or
Other
15%
Natural Forces
14%
Equipment or
Operations
20%
Other O/S Force-
Car
5%
Recent Incident Statistics
2008 Hazardous Liquid Incident Data
Corrosion
20%
Equipment
31%
Outside Force
(TPD)
6%
Incorrect
operations
9%
Material/Const
17%
Naural Forces
5%
Outside Forces
2%
Other
10%
Gas and Liquid IM Programs Progress
Integrity Management Programs
History of the Gas Pipeline Integrity
Industry - Regulator Technical Committee - 1999
ASME B31.8S Standard - Late 2001
NACE ECDA Standard - Late 2002
192 Subpart O - Effective 12/17/2004
NACE SCCDA Standard - Late 2004
NACE ICDA Standard - 2007
Highest 50% of Gas Pipelines Assessed by 12/17/2007
All Gas Pipelines to be Assessed by 12/17/2012
Integrity Management Programs
Where we are today
End of 2008, >98% of gas transmission operators
inspected by state or federal pipeline safety officials
July 2008, operators assessed >75% of HCAs (reporting deadline March 2009)
All Gas HCA mileage inspected by 12/17/12
Large Liquid Operator HCA mileage inspected by
3/31/2008
Small Liquid Operator HCA mileage inspected by
2/17/2009
Integrity Management Programs
Gas Transmission
PARAMETER 12/31/2007 6/30/2008 TOTALS as of 7/1/2008
Total HCA Miles 19,300 19,300 19,300
HCA Miles Inspected 15,057 1,766 16,823
Immediate Repairs Completed 777 256 1,033
Scheduled Repairs Completed 1,752 438 2,190
Total Miles Inspected 291,900 292,600
Total Miles Inspected 96,981 25,947 122,928
Liquid Transmission
PARAMETER 12/31/2007 TOTALS as of 1/1/2008
Total HCA Miles 72,626 72,626
HCA Miles Inspected 72,000 72,000
Immediate Repairs Completed 5,943 5,943
60-Day Repairs Completed 3,951 3,951
180-Day Repairs Completed 16,027 16,027
Total Miles Inspected 461,237 461,237 May have multiple inspections
Casings and Assessments
Integrity Threats to Cased Line Pipe
External Corrosion
Failed end-seals traps moisture inside casings
Coating damage leads to corrosion
poor construction techniques
lack of centralizers
Direct “hard” contacts and electrolytic shorts (coupling) of
cathodic protection system leads to corrosion
Atmospheric Corrosion
Casings and Assessments
Integrity Threats to Cased Line Pipe
Internal Corrosion
Casing generally a low point
under highways or rail crossings
could accumulate liquids
SCC
Same as other line pipe
Casings and Assessments
Integrity Threats to Cased Line Pipe
Seam issues the same
Girth weld issues the same
Construction issues may be increased due to alignment
issues
Casings and Assessments
Casings and Assessments
How large a problem are cased crossings?
Per AGA and INGAA, ~10,000 cased crossings in HCAs
on gas transmission pipelines
At 100‟ per crossing, < 200 miles of ~19,000 miles of
HCA or ~1%
Over entire gas transmission pipeline system:
Expected mileage of cased crossings is 1 to 2%
But number of incidents are unknown
(PHMSA has not tracked this metric)
Casings and Assessments
PHMSA Letter of October 25, 2007 (to AGA)
Recognized acceptable to classify casings as low risk pipe for assessments
Clarified HCA mileage could be reported as complete without casings
Highlighted development efforts for GWUT
Highlighted efforts to assist operators with „Other Technology‟ notifications
Recognized NACE clarification of ECDA application with properly supported engineering and implementation plans per 192.925(b)(1)(ii)
Casings and Assessments
PHMSA Letter of April, 2008 (to AGA)
Agreed - nothing explicit in rule requiring use of Guided
Wave as an indirect inspection tool for assessing
casings
Highlighted rule did not allow risk assessment in lieu of
assessing pipe in an HCA
Highlighted PHMSA efforts for developing guided wave
technology
Suggested workshop for stakeholders as starting point
for determining a solution
Casings and Assessments
Where are we now?
In July 2008 PHMSA held workshop for stakeholders
PHMSA reached out to Industry and Industry
Associations for specific proposals
PHMSA met with AGA to form Joint Technical
Committee (NAPSR, Operators, Service Providers, PHMSA)
Casings and Assessments
Where are we now?
Committee to meet in February
PHMSA supplied AGA with several Key Documents:
Spreadsheet showing reduced assessments (increased time between assessments)
Method to put casings into regions
Thoughts on how filled casing may be considered not to
have external corrosion threat (but still could have internal and SCC threats)
Guidance on how to maximize time between assessments
of casings
Casings and Assessments
Regulations Governing Casings
192.467 – Electrical Isolation
Under IM Rule, assessment limited to casings in an HCA
192.901 – Limits to Gas Transmission
192.919(b) – Align Assessment Methods with threats to
be assessed
192.921 – Requires one of four Assessment Methods
(PT, ILI, DA, Other Technology)
192.925 – Refers to NACE RP 0502 for ECDA
Casings and Assessments
How does NACE RP 0502 handle casings?
Casing are listed in both Table 1 and Table 2
Casings in a separate region from uncased line pipe
Casing indirect inspection tools may need special engineering considerations
Other methods may be used for casing crossings as per section 3.3.2
Indirect inspection tools not listed in Appendix A must
have a procedure, be validated, be appropriate and
effective per 192.925(b)(1)(ii) and section 3.4.3.1 of
NACE RP0502
Casings and Assessments
How does NACE RP 0502 Handle Casings?
Two Complementary Tools
Strengths of one must complement weaknesses of other
(Section 3.4.1.2)
Tools must be selected to reliably detect corrosion
activity and/or coating holidays (Section 3.4.1.1)
Must obtain readings along the entire length of pipe
(Sections 1.2.2.2; 4.2.1.1; 4.1.2 and 4.2.2)
Must align, compare, and classify indications from two
tools (Sections 4.1.2.2; 4.3.2)
Casings and Assessments
PHMSA proposed guidance regarding casings
Proposed ideas
Where assessments have been completed and monitoring
of casings has been performed, reevaluate the need to re-
assess at 7-year interim period
Suggested a methodology to combine similar casings into
regions using NACE RP 0502 as basis
Suggested a methodology to remove threat of external
corrosion from properly filled casings
Casings and Assessments
What are other areas that could be reviewed?
How to assess casing regions so each individual casing
may not have to be excavated and examined
The effect of filling casings on assessments and
corrosion risks
How to eliminate cased crossings from future pipelines
New R & D initiatives to find a technological solution
Casings and Assessments
Performing ECDA over paved surfaces
NACE RP 0502 Tables 1 and 2 state requirements for
using indirect inspection tools over paved surfaces
Per Table 1, these locations may be a separate region
Per Table 2, special engineering considerations (such as
drilling bore holes in pavement) may be necessary to
obtain accurate readings
Casings and Assessments
Performing ECDA Over Paved Surfaces
What are some methods of performing an accurate
ECDA assessment?
Where new pavement or areas without cracks, drill
pavement until soil is reached
Where acceptable readings can be obtained through
pavement, use of special tools may be needed (This is typically in moist or humid environments.)
PHMSA Workshops
PHMSA Planned Workshops for 2009
Internal Corrosion Workshop
March 26, 2009 in Atlanta in conjunction with NACE 2009
Construction Workshop
April 23, 2009 in Dallas – Ft. Worth
Anomaly Repair Workshop – 2nd Installment
Planned during the summer of 2009
Casing Assessment Technical Committee
Ongoing discussion via Joint Technical Committee
(NAPSR, AGA, INGAA, PHMSA), February 2009
Questions
Thank You
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