Reasonable Assurance U

David Smith - EPRINRC/Industry Meeting on BuMarch 30, 2011 White Flint, 
Overview

• Background• Objective• Technical Advisory Group (TAG)• Activities to Date

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ct t es to ate

• Approach• Schedule/Plans
Background

• Underground Piping and Tank Initiative Goal:

– “... provide reasonable assurance of structural and leak

integrity of in-scope underground piping and tanks with emphasis on piping and tanks that contain licensed mat

• Reasonable Assurance:

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– “... establishing and maintaining confidence in undergro

piping and tank integrity based on engineering judgmensupported by facts, actions, knowledge, experience, and

observations. It defines a level of confidence which is debe adequate to support a particular position.”

• Tasked to develop a consensus industry approac
Objectives

• Develop an approach to establishing reaso

assurance for the integrity of buried piping

– Technical Based

Step by Step Process

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– Step by Step Process– Graded Approach– Support the development of buried pipe Inspec

Plans

– Industry consensus approach and application
Technical Advisory Group

• Reasonable Assurance Technical Advisory Group 

– Subset of NEI BPITF– Formed in late October, 2010

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– First Meeting in November, 2010

• Approach had been developed by 2 Utilities

– Used as the basis
Activities to Date

• Reasonable Assurance TAG meeting in Novembe

produced a draft document:

– Document released to the Team for review (La

November) 

– Several rounds of comments

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– Conference Calls and Webcast to discuss

• Provided to NEI BPITF for Review 

– In process
Approach

•Reasonable Assurance 

is a Graded Process that

– Ranks piping– Create Line Groupings– Indirect inspection samples

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Indirect inspection samples

– Direct examinations

Effective use of resources through graded pr

focused and quality inspections
Approach – Ranking

• Susceptibility Analysis and 

Risk Ranking:

– Inventory of buried piping– Risk Ranking based on 

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likelihood and consequence

– Provides input for 

groupings and inspection planning
Approach – Grouping

• Create Line Groupings:

– Optimize Inspections– Separate by Process 

Fluids 

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– Group with similar 

physical attributes

• Material• Coatings• Soil• Age• CP
Indirect Inspections

• Survey techniques used to assess the likelihood o

degradation without having direct access to the 

component. Results are typically qualitative and laccurate than direct examinations. 

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Approach – Indirect Inspections

• Indirect Inspection Selection is 

based on the highest susceptible locations in a line group

– Supports determining the 

number and location of direct

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number and location of direct

examinations

– If indirect inspections not 

applicable go to direct examinations

– Confirmation of indirect 

inspection results with direct examinations
Direct Examinations

• A Nondestructive Evaluation (NDE) examination w

the NDE sensor(s) is in immediate contact with or proximity to the section of the component being examined. Results typically provide some degree quantitative measurement of wall thickness or 

discontinuity size

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discontinuity size. 
Approach – Direct Inspections

• Direct Examinations assess the 

extent of corrosion activity identified by indirect inspections and confirm the effectiveness of the indirect results :

– Graded approach

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Graded approach

• Service Categories• Coverage of indirect inspections• Results of indirect inspections

– Based on highest susceptible 

area if no indirect inspections

– Direct Examination for each 

high ranked grouping
Schedule or Plans

• Remaining Activities:

– NEI BPITF review– NEI BPIWG review

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– Issue as an Appendix to NEI 09-14
Together...Shaping the Future of Elect

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