Southwest Gas Cross Bore Program Joel Martell ManagerEngineering

Southwest Gas Cross Bore Program Joel Martell Manager/Engineering Staff October 30, 2014

Southwest Gas Corporation • Arizona, California and Nevada • 1. 9 million customers • 1, 577 miles gas transmission pipelines • 30, 375 miles gas distribution main • 1. 85 million gas distribution services

Background • Boring is a common method for installing gas facilities in congested or established areas. • Without the benefit of marking sewer laterals, some gas pipelines installed by boring have penetrated those sewer laterals.

SLIP Conflicts

SLIP Timeline Phase I • Began in 2005 • Completed in 2009 Phase II • Began in 2008 • To be completed in 2018 Phase III • Began in 2011 • To be completed in 2018

SLIP Phase I • Priority Customer Classes: – – – • • • Schools Hospitals Nursing homes Mobile home parks Apartment complexes Sewer Laterals Database Field Investigations Public Education

Investigation Methods • Maps and Records review • Physical separation of at least 18 inches • Video inspection • Dig and Inspect

Video Inspection Technology

Sewer Lateral and Main Cameras

SLIP Phase I Data Investigation Total 5/2004 - 7/2009 Conflicts found: Phase One Central Arizona 63, 959 49 Northern Nevada 23, 605 1 Southern Arizona 67, 417 6 Southern California 8, 547 1 Southern Nevada 92, 444 5 Total 255, 972 62

SLIP Phase II Criteria • Any service pipe replacement project where boring is known to have occurred as an installation method • Random service pipe replacement completed between applicable dates determined by each division • Propane and electric conversion projects where boring occurred • Phase II pilot began in 2007 • Companywide Phase II began in 2009

SLIP Phase II Investigations Phase II: Approx. Field Investigations Phase II: Approx. Office Investigations Total Phase II Investigations Percent Complete Central Arizona 40, 500 109, 500 150, 000 78% Northern Nevada 6, 712 18, 932 25, 644 10% Southern Arizona 92, 900 283, 600 376, 500 73% Southern California 13, 310 11, 963 25, 273 100% Southern Nevada 2, 417 777 3, 194 100% 155, 839 424, 772 580, 611 TOTAL

SLIP Phase III Criteria Gas main known to be installed by boring prior to April 2002 in AZ and January 2003 in NV and CA: • Main pipe replacement projects • Random main pipe replacement • Propane and electric conversion projects where boring occurred • Master meter replacement projects Phase III was authorized in 2011.

SLIP Phase III Investigations Total Phase III Mileage Central Arizona 3, 615 Northern Nevada 72 Southern Arizona 816 Southern California 794 Southern Nevada Total 56 5, 353

Public Education & Communication • Targeted public are part of an ongoing public awareness program to provide further education and communication related to potential sewer lateral conflicts. • The targeted public education is directed to the following: – – – • Plumbing contractors Equipment rental companies Excavators Available in English and Spanish

Public Education & Communication

Rental Equipment Stores: SLIP Brochures 2014 Division 2012 2013 CAZ 1747 1755 1810 NNV 89 228 313 SAZ 917 480 402 SCA 52 180 192 SNV 816 1218 729 Total 3621 3861 3446 YTD

Overall SLIP Conflicts Data Total Plumber Calls 18 179 31 1 3 34 1 13 2 6 27 8 1 2 2 1 6 2 5 7 3 4 19 2 62 99 72 32 265 44 Post-2002 Phase III Conflicts Phase II Central Arizona 49 48 64 Northern Nevada 1 29 Southern Arizona 6 Southern California Southern Nevada TOTAL

SLIP Costs • Costs vary based on equipment used • New buildings with clean-outs inexpensive • Older neighborhoods requiring full sewer inspections more costly • Experienced vs. inexperienced contractors • Quality of work • Price of work

Current Approach • Continued Public Education § § Plumbers Excavators Residential Customers Rental Equipment Locations • Revisions to company procedures

Revised Procedures Insertion Installations • Pre-installation camera inspection Pipe splitting • Post-installation camera inspection Boring • Post-installation camera inspection or pullback camera inspection

Cross Bore Summary • Sewer lateral conflicts are threats to the integrity of distribution pipelines • Sewer lateral investigation programs have been effective in mitigating risks • Public education programs have been effective in mitigating risks • More preventative measures are needed in terms of marking sewer laterals to eliminate conflicts right from the start

Questions?