Questars Gas Storage Facilities in the West Brent

Questar’s Gas Storage Facilities in the West Brent Kitchen Supervisor, Pipeline Marketing

Questar Pipeline Storage Facilities Peaking Storage (3) Salt Cavern Storage (Proposed) WYOMING Kanda Hub Proposed Clay Basin UTAH COLORADO

Present Storage Facilities Name Clay Basin Leroy Coalville Chalk Creek Type Depleted Gas Aquifer Formation Dakota Thaynes Longwall Kelvin Horsepower 32, 500 3830 1600 550 Max. W/D 765 MMCF 75 MMCFD 65 MMCFD 35 MMCFD Working 51. 25 BCF . 836 BCF . 692 BCF . 256 BCF Cushion 66. 21 BCF 5. 62 BCF 2. 13 BCF 1. 27 BCF Total 117. 5 BCF 6. 41 BCF 2. 74 BCF 1. 18 BCF Pressure 2600 psig 1540 psig 1144 psig 1125 psig

Clay Basin Storage Facility

WYOMING Rock Springs 50 Miles Clay Basin is connected to both Questar and Northwest Pipeline. COLORADO Salt Lake City 140 Miles UTAH

Clay Basin Storage Facilities n n n Five 2, 600 HP reciprocating compressors Three 6, 500 HP turbine compressors One Park and Loan compressor 89, 000 feet of 6 and 10 inch field lines 29 field dehydration units 44 injection and withdrawal wells

Clay Basin’s Geology The Clay Basin Field is a anticlinal dome about four miles long and two miles wide that underlies some 4, 680 acres.

Present Customer Mix

Clay Basin Storage

Clay Basin January Averages

Clay Basin Service Opportunities n n n Firm Storage Service Capacity Release Interruptible Storage Service Release of Injection/Withdrawal rights In-place Transfers Park and Loan (PAL 1)

Questar Hub Services Questar offers two types of Park and Loan service levels, PAL 1 and PAL 2. n Service Priority; FSS, PAL 1, ISS, PAL 2. n Questar’s Representative for PAL services is Marty Anderson 801 324 -2017 n

Questar’s Future Storage Projects n Questar Pipeline is currently exploring two storage projects to meet the needs of its customers l l Southwest Wyoming Salt Cavern project near Evanston, Wyoming (salt cavern) Kanda Hub Storage Project near Rock Springs, Wyoming (depleted gas field)

Questar Project Status n n Work is continuing on both storage projects, however the primary focus is on the depleted gas storage project with the potential to tie to multiple large diameter pipelines Assuming that gas prices decline and stabilize in the near future, an open season is anticipated in 2004 for the Kanda Hub Project

Why Salt? n Caverns can be emptied and refilled quickly l n Salt is an excellent sealant l n High injection and withdrawal rates make them well-suited to meet peaking requirements multiple times during the same demand period Impervious to natural gas and seals itself (“creep”) The salt is strategically located

Project History n Drilled analyzed core hole test well in Pruess Formation l n Conducted initial project feasibility studies l n 3, 000 ft deep, 2, 000 ft thick Consultant: Sofregaz US Inc. Acquired necessary leases and rights l l Leases for caverns and disposal wells Options for water rights from City of Evanston

Project Feasibility n n Salt Water Brine disposal Location l l Proposed initial pipelines ties are Kern River and Questar Pipeline As market demand requires we will tie to the other major pipelines in the area

Capacity and Deliverability n Potential for five caverns l n Sequential cavern development Storage capacity of 2. 5 Bcf working gas and 1. 1 Bcf cushion gas per cavern n n Deliverability of 250 MMcf/day per cavern Injection of 125 MMcf/day per cavern

Current Status n Disposal test well to Nugget Formation l l l n Core and log Twin Creek and Nugget Formations Open-hole injectivity test of Nugget Disposal options: Reinjection, settling ponds and/or combination of these Engineering design l Preliminary cavern design and brine disposal l Pipeline routes and operating facilities (Questar)

Rock Springs Storage Project n n Preliminary engineering underway to determine project capacity, cost and timing Projected size ranging from 15 Bcf to 20 Bcf working gas Anticipated interconnects with Questar Pipeline, Overthrust, CIG, WIC and Overland Trail Projected in service 2007 - 08

Summary n Questar Pipeline is focused on providing transportation and storage service that will improve market access for Rocky Mountain gas supply. Implementing solutions to meet customer needs continues to be our goal in a challenging environment. We look forward to working with our energy partners to find those solutions.