1 

## Accelerated Main Renewal Program (AMRP)
April 11, 2012 Michael Bruno & Jonathan Moe2 

## Scope
 Accelerated Main Renewal Program (AMRP) is a proactive program to renew aging main in Xcel Energy’s Colorado territory  Focusing on distribution main below 150 pounds per square inch (psi)3 

## Scope
 Total Mileage  Cast Iron (CI)
– 120 Miles  Bare Steel (BS)
– 99 Miles  Polyvinyl Chloride (PVC)
– 455 Miles  Started 2008
– Expected finish date 20294 

## Identifying Emission Sources

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

2004 2005 2006 2007 2008 2009 2010 2011 YearLeaks / Mile Bare Steel Cast Iron PVC Coated Steel PE

Doesn’t contain third party damages, service leakage, or meter leakage5 

## Emissions by Pipe Type

Type MCF/Mi/Yr Bare Steel 110

Cast Iron 239 PVC 12 Coated Steel 3 PE 12 From the Xcel Energy Natural GasSTAR filing for 20106 

## Total Leakage Emissions
5% 14%
3%
12% 66% Bare Steel Cast Iron PVC Coated Steel PE7 

## Top Offenders
 Three pipe types (CI, BS, and PVC) account for 24% of the yearly leakage emissions  They represent only 3.4% of Xcel Energy’s distribution main8 

## Top Offenders
 The AMRP project targeted these three pipe types  Total Mileage (2008)  Cast Iron
– 120 Miles  Bare Steel
– 99 Miles  PVC
– 455 Miles9 

## Project Risk Ranking
 Leakage History  Corrosion Issues  Emissions  Pressure  Class Location10 

## Project Planning

GIS

Passport Optimain Planning Tool Budget

Project List11 

## Project Team Project Manager

Field Supervisors

Contractors Engineering
Design

Team Planning12 

## Regulatory Environment
 Xcel Energy proactively approached the Colorado Public Utilities Commission (CPUC) about the project  As a result:  Xcel Energy has committed to renewal all cast iron, bare steel, and PVC main  Xcel Energy has committed to renew all of the cast iron in Colorado by 201513 

## Regulatory Environment
 As a result:  3 Year Deal with annual reset  Annual Filing Requirement  Annual True Up Mechanism  Annual filing of results compared to plan  PUC can deny recovery14 

## Progress to Date
 Miles Renewed  Cast Iron
– 89.1 Miles  Bare Steel
– 12.7 Miles  PVC
– 8.1 Miles  Total – 109.9 Miles15 

## Miles Remaining By Year

- 50 100 150 200 250 300 350 400 450 500

2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 

### YearMiles Remaining CI Bare Steel PVC16 

## Leakage Emissions

- 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 45,000 50,000

2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 YearMSCF/Yr17 

## Current Reduction Methods
 System Pressure Reductions for tie ins and blow downs  Renewal of leaking main  Flaring18 

## Future Reductions Methods
 Mobile Compression Unit  Allows us to pump the gas out of a main into the surrounding gas system instead of releasing it into the atmosphere  Focused procedures designed to lower the amount of gas vented to the atmosphere during these projects19 

### Xcel Energy 2010 GasSTAR Reductions 113,659 MSCF

74% 11% 9% 7% Directed Inspection and Maintenance Modified Blow Down Methods Distribution Pipe Renewals Instrument Systems Converted to Air20 

## Xcel Energy Cumulative Reductions
Cumulative Reductions 181,618 MSCF

47%

20% 18% 15% Directed Inspection and Maintenance Modified Blow Down Methods Distribution Pipe Renewals Instrument Systems Converted to Air21