UNITED STATES SECURITIES AND EXCHANGE COMMISSION  Washington, D.C.  20549  FORM 10-Q  [X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934  For the quarter ended June 30, 2007  [  ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934  For the transition period from ___ to ___  Commission File Number 1-935  QUESTAR GAS COMPANY (Exact name of registrant as specified in charter)  STATE OF UTAH 87-0155877 (State or other jurisdiction of (I.R.S. Employer incorporation or organization) Identification No.)  180 East 100 South Street, P.O. Box 45360 Salt Lake City, Utah 84145-0360(Address of principal executive offices) Registrants telephone number, including area code (801) 324-5555  Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.  Yes [X]     No [  ]  Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of accelerated filer and large accelerated filer in Rule 12b-2 of the Exchange Act. (Check one): Large accelerated filer [  ]                              Accelerated filer [  ]                         Non-accelerated filer [X]  Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).  Yes [  ]     No [X]  On July 31, 2007, 9,189,626 shares of the registrants common stock, $2.50 par value, were outstanding (all shares are owned by Questar Corporation).  Registrant meets the conditions set forth in General Instruction H (1) (a) and (b) of Form 10-Q and is filing this Form 10-Q with the reduced disclosure format.


Questar Gas Company Form 10-Q for the Quarter Ended June 30, 2007  TABLE OF CONTENTS   Page PART I. FINANCIAL INFORMATION  ITEM 1. FINANCIAL STATEMENTS (Unaudited) 3  Statements of Income for the three, six and twelve months ended 3 June 30, 2007 and 2006  Condensed Balance Sheets as of June 30, 2007, June 30, 2006 4 and December 31, 2006  Condensed Statements of Cash Flows for the six months ended 5 June 30, 2007 and 2006  Notes Accompanying the Condensed Financial Statements 6  ITEM 2. MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION 6 AND RESULTS OF OPERATIONS  ITEM 4T. CONTROLS AND PROCEDURES 9  PART II. OTHER INFORMATION  ITEM 1A. RISK FACTORS 10  ITEM 6. EXHIBITS 10  Signatures 10     Questar Gas Company Form 10-Q 2   PART I. FINANCIAL INFORMATION   ITEM 1.  FINANCIAL STATEMENTS.  QUESTAR GAS COMPANYSTATEMENTS OF INCOME(Unaudited)3 Months Ended
June 30,6 Months Ended
June 30,12 Months Ended
June 30,200720062007200620072006(in millions)REVENUESFrom unaffiliated customers$141.7$181.9$548.2$648.8$958.5$1,110.5From affiliated companies2.11.23.22.85.96.3Total Revenues143.8183.1551.4651.6964.41,116.8OPERATING EXPENSESCost of natural gas sold101.4137.9412.4509.1725.1865.3Operating and maintenance16.217.337.338.472.176.2General and administrative11.110.822.620.444.138.7Depreciation and amortization9.610.619.122.237.845.8Other taxes3.63.77.27.311.511.9Total Operating Expenses141.9180.3498.6597.4890.61,037.9Net loss from asset sales(0.1)(0.3)(0.3)OPERATING INCOME1.92.752.853.973.878.6Interest and other income2.11.54.03.07.65.4Interest expense(5.9)(5.4)(11.9)(10.9)(23.6)(21.2)INCOME (LOSS) BEFORE INCOME TAXES(1.9)(1.2)44.946.057.862.8Income taxes(0.8)(0.5)16.917.321.523.4NET INCOME (LOSS)($ 1.1)($  0.7)$ 28.0$  28.7$ 36.3$  39.4   See notes accompanying the condensed financial statements


Questar Gas Company Form 10-Q 3


QUESTAR GAS COMPANYCONDENSED BALANCE SHEETSJune 30,December 31,200720062006(Unaudited)(in millions)ASSETSCurrent AssetsCash and cash equivalents$     3.6Note receivable from Questar$  16.8$    9.8Accounts receivable, net41.058.583.3Unbilled-gas accounts receivable7.613.067.5Accounts receivable from affiliates2.52.22.1Gas stored underground33.536.550.2Materials and supplies11.310.37.8Prepaid expenses and other1.80.92.1Deferred income taxes  current1.711.81.7Total Current Assets116.2143.0218.3Property, Plant and Equipment1,460.61,365.01,418.1Accumulated depreciation and amortization(612.7)(583.8)(598.0)Net Property, Plant and Equipment847.9781.2820.1Regulatory assets24.722.623.0Goodwill5.65.65.6Other noncurrent assets6.26.46.3Total Assets$1,000.6$ 958.8$1,073.3LIABILITIES AND COMMON SHAREHOLDERS EQUITYCurrent LiabilitiesChecks outstanding in excess of cash$       3.8$  2.2Notes payable to Questar$    13.2Accounts and other payables56.276.7131.1Accounts payable to affiliates31.226.532.6Customer-credit balances16.48.431.4Fair value of derivative contracts7.6Purchased-gas adjustment54.128.534.3Current portion of long-term debt53.010.0Total Current Liabilities214.7142.3260.2Long-term debt, less current portion270.0323.0313.0Deferred income taxes119.8118.1118.7Other long-term liabilities51.741.251.8COMMON SHAREHOLDERS EQUITYCommon stock23.023.023.0Additional paid-in capital116.3115.7116.0Retained earnings205.1195.5190.6Total Common Shareholders Equity344.4334.2329.6Total Liabilities and Common Shareholders Equity$1,000.6$ 958.8$1,073.3   See notes accompanying the condensed financial statements


Questar Gas Company Form 10-Q 4


QUESTAR GAS COMPANYCONDENSED STATEMENTS OF CASH FLOWS(Unaudited)6 Months Ended June 30,20072006(in millions)OPERATING ACTIVITIESNet income$  28.0$  28.7Adjustments to reconcile net income to netcash provided from operating activities:Depreciation and amortization21.024.1Deferred income taxes1.1(25.8)Share-based compensation0.30.4Net loss from asset sales0.3Changes in operating assets and liabilities42.9111.3NET CASH PROVIDED FROM OPERATING ACTIVITIES93.3139.0INVESTING ACTIVITIESCapital expenditures(57.5)(44.6)Proceeds from asset dispositions0.30.7NET CASH USED IN INVESTING ACTIVITIES(57.2)(43.9)FINANCING ACTIVITIESChange in notes receivable from Questar(16.8)(9.8)Change in notes payable to Questar(13.2)(77.4)Checks outstanding in excess of cash3.82.2Dividends paid(13.5)(13.3)NET CASH USED IN FINANCING ACTIVITIES(39.7)(98.3)Change in cash and cash equivalents(3.6)(3.2)Beginning cash and cash equivalents3.63.2Ending cash and cash equivalents$     -$    -   See notes accompanying the condensed financial statements


Questar Gas Company Form 10-Q 5


QUESTAR GAS COMPANY  NOTES ACCOMPANYING THE CONDENSED FINANCIAL STATEMENTS  Note 1  Nature of Business  Questar Gas Company (Questar Gas or Company) is a wholly owned subsidiary of Questar Corporation (Questar). The Company provides retail natural gas distribution in Utah, southwestern Wyoming and a small portion of southeastern Idaho. Questar Gas is regulated by the Public Service Commission of Utah (PSCU) and the Public Service Commission of Wyoming (PSCW). The Public Utility Commission of Idaho has contracted with the PSCU for rate oversight of Questar Gass Idaho operations.  Note 2  Basis of Presentation of Interim Financial Statements  The accompanying unaudited condensed financial statements were prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and pursuant to the rules and regulations of the SEC. The interim condensed financial statements reflect all normal, recurring adjustments and accruals that are, in the opinion of management, necessary for a fair presentation of financial position and results of operations for the interim periods presented. Interim financial statements do not include all of the information and notes required by GAAP for audited annual financial statements. These condensed financial statements should be read in conjunction with the financial statements and notes thereto included in the Companys Annual Report on Form 10-K for the year ended December 31, 2006. Certain reclassifications were made to prior-period financial statements to conform with the current presentation.  The preparation of the condensed financial statements and notes in conformity with GAAP requires that management make estimates and assumptions that affect the amounts of assets and liabilities and disclosure of contingent assets and liabilities. Actual results could differ from estimates. The results of operations for the three, six and twelve months ended June 30, 2007, are not necessarily indicative of the results that may be expected for the year ending December 31, 2007.  All dollar amounts in this quarterly report on Form 10-Q are in millions, except where otherwise noted.  Note 3  Accounting for Uncertainty in Income Taxes  In July 2006, the Financial Accounting Standards Board (FASB) issued FASB Interpretation 48, Accounting for Uncertainty in Income Taxes (FIN 48). The interpretation applies to all tax positions related to income taxes subject to FASB Statement 109 Accounting for Income Taxes. FIN 48 provides guidance for the accounting for uncertainty in income taxes by prescribing a minimum recognition threshold for a tax position to be reflected in the financial statements. If recognized, the tax benefit is measured as the largest amount of tax benefit that is more-likely-than-not to be realized upon ultimate settlement. Questar Gas adopted the provisions of FIN 48 on January 1, 2007. Management has considered the amounts and the probabilities of the outcomes that could be realized upon ultimate settlement and believes that it is more-likely-than-not that the Companys recorded income tax benefits will be fully realized. There were no unrecognized tax benefits at the beginning or at the end of the six-month period ended June 30, 2007. Questars federal income tax returns for the years 1999 through 2004 are currently under examination.  The Company records interest earned on income-tax refunds in interest and other income and penalties and interest charged on tax deficiencies in interest expense. As of the date of adoption, there were no amounts accrued for penalties or interest related to unrecognized tax benefits.   ITEM 2. MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.  The following discussion updates information as to Questar Gass financial condition provided in its previous Form 10-K filing, and analyzes the changes in the results of operations between the three-, six- and twelve-month periods ended June 30, 2007 and 2006. For definitions of commonly used gas and oil terms found in this Form 10-Q, please refer to the Glossary of Commonly Used Terms provided in the Companys 2006 Form 10-K.


Questar Gas Company Form 10-Q 6


RESULTS OF OPERATIONS  Questar Gas reported a net loss of $1.1 million in the second quarter of 2007 compared with a net loss of $0.7 million in the second quarter of 2006. Net income was $28.0 million in the first half of 2007 compared with $28.7 million in the first half of 2006. Questar Gas reported net income of $36.3 million for the 12 months ended June 30, 2007, compared to $39.4 million for the year-earlier period.  Operating income decreased $0.8 million in the 2007 to 2006 second quarter comparison, $1.1 million in the 2007 to 2006 first half comparison and $4.8 million in the 2007 12 months ended June 30, 2007 comparison with the prior year period due to lower customer rates and higher expenses offsetting the revenues from customer growth. Following is a summary of Questar Gass financial and operating results:  3 Months Ended June 30,6 Months Ended June 30,12 Months Ended June 30,200720062007200620072006(in millions)OPERATING INCOMERevenuesResidential and commercial sales$128.2$162.4$520.4$603.9$904.9$1,017.9Industrial sales2.38.45.118.010.639.0Transportation for industrial customers2.31.44.63.08.36.0Service1.62.03.44.26.37.1Other9.48.917.922.534.346.8Total revenues143.8183.1551.4651.6964.41,116.8Cost of natural gas sold101.4137.9412.4509.1725.1865.3Margin42.445.2139.0142.5239.3251.5Other operating expensesOperating and maintenance16.217.337.338.472.176.2General and administrative11.110.822.620.444.138.7Depreciation and amortization9.610.619.122.237.845.8Other taxes3.63.77.27.311.511.9Total other operating expenses40.542.486.288.3165.5172.6Net loss from asset sales(0.1)(0.3)(0.3)Operating income$  1.9$  2.7$  52.8$  53.9$  73.8$  78.6OPERATING STATISTICSNatural gas volumes (MMdth)Residential and commercial sales15.116.761.059.0104.298.5Industrial sales0.41.20.82.31.64.9Transportation for industrial customers11.07.320.915.840.631.3Total industrial11.48.521.718.142.236.2Total deliveries26.525.282.777.1146.4134.7Natural gas revenue (per dth)Residential and commercial sales$8.51$9.73$8.53$10.24$8.68$10.33Industrial sales5.887.446.397.916.648.02Transportation for industrial customers$0.21$0.19$0.22$ 0.19$0.20$  0.19Temperatures  colder (warmer) than normal(16%)(25%)normal(7%)2%(6%)Temperature − adjusted usage per customer (dth)16.818.165.468.5110.5113.7Customers at June 30, (thousands)862.1835.5  Margin Analysis Questar Gas’s margin (revenues less gas costs) decreased $2.8 million in the second quarter of 2007 compared to the second quarter of 2006, $3.5 million in the first half of 2007 compared to the first half of 2006 and $12.2 million in the 12 months ended June 30, 2007 compared to the same period ended June 30, 2006. Following is a summary of major changes in Questar Gass margin:


Questar Gas Company Form 10-Q 7


Change in Margin3 Months Ended June 30,6 Months Ended June 30,12 Months Ended June 30,2007 Compared with 20062007 Compared with 20062007 Compared with 2006(in millions)New customers$1.2$3.9$    6.8Conservation-enabling tariff2.13.92.2Change in usage per customer(2.0)(5.0)(5.2)Change in rates(1.1)(6.2)(11.5)Recovery of gas-cost portion of bad-debt costs(1.1)(2.5)(6.1)Change in transportation revenue0.91.62.22006 adjustment to unbilled revenues(2.7)Other, including shifting between rate classes(0.1)0.8(0.6)Decrease($2.8)($3.5)($12.2)  At June 30, 2007, Questar Gas served 862,053 customers, up from 835,511 at June 30, 2006. Customer growth increased the margin by $1.2 million in the second quarter of 2007, $3.9 million in the first half of 2007 and $6.8 million in the 12 months ended June 30, 2007.  Temperature-adjusted usage per customer decreased 7% in the second quarter of 2007, 5% in the first half of 2007 and 3% in the 12 months ended June 30, 2007 compared to the same periods of 2006. The impact on the companys margin from changes in usage per customer has been mitigated by a pilot conservation-enabling tariff that was approved by the PSCU in October 2006, effective back to the beginning of 2006. The new tariff resulted in a margin increase of $2.1 million in the second quarter of 2007, $3.9 million in the first half of 2007 and $2.2 million in the 12 months ended June 30, 2007, largely offsetting the decline in usage per customer.  Effective June 1, 2006, gas rates for Utah customers were reduced by $9.7 million per year, primarily to reflect reductions in the companys depreciation expense. Questar Gas realized $1.1 million in reduced revenues from this rate change during the second quarter of 2007, $6.2 million in the first half of 2007 and $11.5 million in the 12 months ended June 30, 2007 compared to the same periods of 2006. A depreciation rate change reduced depreciation expense approximately $1.5 million in the second quarter of 2007, $3.8 million in the first half of 2007 and $8.5 million in the 12 months ended June 30, 2007 compared to the prior year periods.  Weather, as measured in degree days, was 16% warmer than normal in the second quarter of 2007, normal in the first half of 2007 and 2% colder than normal in the 12 months ended June 30, 2007. A weather-normalization adjustment on customer bills generally offsets financial impacts of moderate temperature variations.  During the second quarter of 2006, Questar Gas increased its estimate of unbilled revenues, which increased the margin by $2.7 million.  Expenses Cost of natural gas sold decreased 26% in the second quarter of 2007, 19% in the first half of 2007 and 16% in the 12 months ended June 30, 2007 compared to the same periods of 2006 primarily due to lower gas purchase expenses per dth. Questar Gas accounts for purchased-gas costs in accordance with procedures authorized by the PSCU and the PSCW. Purchased-gas costs that are different from those provided for in present rates are accumulated and recovered or credited through future rate changes. As of June 30, 2007, Questar Gas had a $54.1 million over-collected balance in the purchased-gas adjustment account representing costs recovered from customers in excess of costs incurred.  Operating, maintenance, general and administrative expenses decreased 3% in the second quarter of 2007, increased 2% in the first half of 2007 and increased 1% in the 12 months ended June 30, 2007 compared to the same periods of 2006. Higher labor and benefit costs were more than offset by lower bad-debt costs. Operating, maintenance, general and administrative expenses per customer were $69 in the first half of 2007 compared to $70 in the first half of 2006.


Questar Gas Company Form 10-Q 8


Depreciation expense decreased 9% in the second quarter of 2007, 14% in the first half of 2007 and 17% in the 12 months ended June 30, 2007 compared to the same periods of 2006 primarily as a result of reduced depreciation rates effective June 1, 2006, in accordance with the PSCU order discussed above. Reduced depreciation rates offset the depreciation impact of plant additions from customer growth.  Forward-Looking Statements This quarterly report may contain or incorporate by reference information that includes or is based upon forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements give expectations or forecasts of future events. You can identify these statements by the fact that they do not relate strictly to historical or current facts. They use words such as anticipate, estimate, expect, project, intend, plan, believe, and other words and terms of similar meaning in connection with a discussion of future operating or financial performance. In particular, these include statements relating to future actions, prospective services or products, future performance or results of current and anticipated services or products, exploration efforts, expenses, the outcome of contingencies such as legal proceedings, trends in operations and financial results.  Any or all forward-looking statements may turn out to be wrong. They can be affected by inaccurate assumptions or by known or unknown risks and uncertainties. Many such factors will be important in determining actual future results. These statements are based on current expectations and the current economic environment. They involve a number of risks and uncertainties that are difficult to predict. These statements are not guarantees of future performance. Actual results could differ materially from those expressed or implied in the forward-looking statements. Among factors that could cause actual results to differ materially are:  · the risk factors discussed in Part I, Item 1A of the Companys Annual Report on Form 10-K for the year ended December 31, 2006; · general economic conditions, including the performance of financial markets and interest rates; · changes in industry trends; · changes in laws or regulations; and · other factors, most of which are beyond control.  Questar Gas undertakes no obligation to publicly correct or update the forward-looking statements in this quarterly report, in other documents, or on the Web site to reflect future events or circumstances. All such statements are expressly qualified by this cautionary statement.   ITEM 4T.  CONTROLS AND PROCEDURES.  Evaluation of Disclosure Controls and Procedures The Companys Chief Executive Officer and Chief Financial Officer have evaluated the effectiveness of the Companys disclosure controls and procedures (as such term is defined in Rules 13a-15(e) under the Securities Exchange Act of 1934, as amended (the Exchange Act)) as of the end of the period covered by the report (the Evaluation Date). The effectiveness of the Companys internal control over financial reporting was assessed using criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in Internal Control  Integrated Framework. Based on such evaluation, such officers have concluded that, as of the Evaluation Date, the Companys disclosure controls and procedures are effective in alerting them on a timely basis to material information relating to the Company required to be included in the Companys reports filed or submitted under the Exchange Act. The Companys Chief Executive Officer and Chief Financial Officer also concluded that the controls and procedures were effective in ensuring that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the Companys management including its principal executive and financial officers or persons performing similar functions as appropriate to allow timely decisions regarding required disclosure.  This quarterly report does not include an attestation report of the Companys registered public accounting firm regarding internal control over financial reporting.  Changes in Internal Controls Since the Evaluation Date, there have not been any changes in the Companys internal controls or other factors during the most recent fiscal quarter that could materially affect such controls.


Questar Gas Company Form 10-Q 9


PART II.  OTHER INFORMATION    ITEM 1A.  RISK FACTORS  Questar may be subject to future greenhouse gas regulation.On April 2, 2007, the U.S. Supreme Court issued its decision in Massachusetts v. EPA, in which the Court held that carbon dioxide, a greenhouse gas, is a pollutant regulated under the Clean Air Act and that EPA has a duty to make a determination regarding whether emissions of carbon dioxide from mobile sources endanger health and the environment. Although the decision addresses mobile source emissions, it is already being cited in other pending litigation as support for the proposition that EPA should promulgate National Ambient Air Quality Standards for carbon dioxide with attendant direct restrictions on emissions of carbon dioxide from stationary sources of air emissions. In addition to this legal development, there are a number of bills pending in Congress which would regulate greenhouse gas emissions through a cap-and-trade system under which emitters of greenhouse gases would be allocated or sold allowances to permit emissions of greenhouse gases. While it is likely that there will be regulation of greenhouse gas emissions in the next few years, it is too early to predict with any certainty how this regulation will affect Questars business, operations or financial results.  ITEM 6.  EXHIBITS.  a. The following exhibits are filed as part of this report:  Exhibit No. Exhibits  31.1. Certification signed by Alan K. Allred, Questar Gas Companys President and Chief Executive Officer, pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.  31.2. Certification signed by S. E. Parks, Questar Gas Companys Vice President and Chief Financial Officer, pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.  32. Certification signed by Alan K. Allred and S. E. Parks, Questar Gas Companys President and Chief Executive Officer and Vice President and Chief Financial Officer, respectively, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.    SIGNATURES  Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.  QUESTAR GAS COMPANY (Registrant)   August 9, 2007 /s/Alan K. Allred Alan K. Allred President and Chief Executive Officer    August 9, 2007 /s/S/ E. Parks S. E. Parks Vice President and Chief Financial Officer


Questar Gas Company Form 10-Q 10


Exhibits List  Exhibit No. Exhibits  31.1. Certification signed by Alan K. Allred, Questar Gas Companys President and Chief Executive Officer, pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.  31.2. Certification signed by S. E. Parks, Questar Gas Companys Vice President and Chief Financial Officer, pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.  32. Certification signed by Alan K. Allred and S. E. Parks, Questar Gas Companys President and Chief Executive Officer and Vice President and Chief Financial Officer, respectively, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.  Exhibit 31.1.  CERTIFICATION  I, Alan K. Allred, certify that:  1. I have reviewed this quarterly report of Questar Gas Company on Form 10-Q for the period ending June 30, 2007;  2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this quarterly report;  3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;  4. The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and we have:  a) designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;  b) evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and  c) disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting.  5. The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of registrants board of directors (or persons performing the equivalent function):  a) all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and


Questar Gas Company Form 10-Q 11


b) any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.  August 9, 2007 /s/Alan. K. Allred Alan K. Allred President and Chief Executive Officer  Exhibit 31.2.  CERTIFICATION   I, S. E. Parks, certify that:  1. I have reviewed this quarterly report of Questar Gas Company on Form 10-Q for the period ending June 30, 2007;  2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this quarterly report;  3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;  4. The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and we have:  a) designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;  b) evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and  c) disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting.  5. The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of registrants board of directors (or persons performing the equivalent function):  a) all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and  b) any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.  August 9, 2007 /s/S. E. Parks S. E. Parks Vice President and Chief Financial Officer


Questar Gas Company Form 10-Q 12


Exhibit No. 32.  CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002   In connection with the quarterly report of Questar Gas Company (the Company) on Form 10-Q for the period ending June 30, 2007, as filed with the Securities and Exchange Commission on the date hereof (the Report), Alan K. Allred, President and Chief Executive Officer of the Company, and S. E. Parks, Vice President and Chief Financial Officer of the Company, each hereby certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to the best of his knowledge:  (1) The Report fully complies with the requirements of Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934; and  (2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.  QUESTAR GAS COMPANY    August 9, 2007 /s/Alan K. Allred Alan K. Allred President and Chief Executive Officer    August 9, 2007 /s/S. E. Parks S. E. Parks Vice President and Chief Financial Officer


Questar Gas Company Form 10-Q 13