UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549  FORM 10-Q/A Amendment No. 1  [X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. For the quarterly period ended September 30, 2011  [   ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. For the transition period from ___ to ___  Exact name of registrant as specified in its charterState or other jurisdiction or incorporation of organizationCommission File Number(I.R.S. Employer
Identification No.)Questar CorporationUtah001-0879687-0407509Questar Pipeline CompanyUtah000-1414787-0307414Questar Gas CompanyUtah333-6921087-0155877  180 East 100 South Street, P.O. Box 45433 Salt Lake City, Utah 84145-0433 (Address of principal executive offices)  Registrants telephone number, including area code (801) 324-5000 Web sitehttp://www.questar.com  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.  Questar CorporationYes [X]   No [   ]Questar Pipeline CompanyYes [X]   No [   ]Questar Gas CompanyYes [X]   No [   ]  Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (Section 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).  Questar CorporationYes [X]   No [   ]Questar Pipeline CompanyYes [   ]   No [   ]Questar Gas CompanyYes [   ]   No [   ]  Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. Do not check non-accelerated filer if a smaller reporting company (Check one):  Questar CorporationLarge accelerated filer [X]Accelerated filer [   ]Non-accelerated filer [   ]Smaller reporting company [   ]Questar Pipeline CompanyLarge accelerated filer [   ]Accelerated filer [   ]Non-accelerated filer [X]Smaller reporting company [   ]Questar Gas CompanyLarge accelerated filer [   ]Accelerated filer [   ]Non-accelerated filer [X]Smaller reporting company [   ]  Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).  Questar CorporationYes [   ]   No [X]Questar Pipeline CompanyYes [   ]   No [X]Questar Gas CompanyYes [   ]   No [X]   Indicate the number of shares outstanding of each of the issuers classes of common stock, as of December 12, 2011:  Questar Corporationwithout par value177,770,548Questar Pipeline Company$1.00 per share par value6,550,843Questar Gas Company$2.50 per share par value9,189,626  Questar Pipeline Company and Questar Gas Company, as wholly-owned subsidiaries of a reporting company, meet the conditions set forth in General Instruction H(1)(a) and (b) of Form 10-Q and are therefore filing this form with the reduced disclosure format.


QUESTAR CORPORATION (Questar) QUESTAR PIPELINE COMPANY (Questar Pipeline) QUESTAR GAS COMPANY (Questar Gas) FORM 10-Q/A Amendment No. 1 FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 2011  EXPLANATORY NOTE   Pursuant to this Amendment No. 1 to the Quarterly Report on Form 10-Q/A, the registrants amend and restate Part II - Item 6 (Exhibits) of their Quarterly Report on Form 10-Q for the period ended September 30, 2011 in its entirety to add Exhibit 10.1 that was inadvertently omitted from the original filing. Other than the foregoing and the recently-dated certifications of the registrants, as required by Rule 12b-15 under the Securities Exchange Act of 1934, no other changes have been made to the registrants Quarterly Report on Form 10-Q for the period ended September 30, 2011. This Amendment No. 1 does not reflect events occurring after the filing on November 4, 2011 of the original Quarterly Report on Form 10-Q with the Securities and Exchange Commission, or modify or update the disclosures presented in the original Quarterly Report on Form 10-Q, except to reflect the revisions as described above.  ITEM 6.  EXHIBITS.  Exhibit No.Description of Exhibit10.1*First Amendment, dated as of September 2, 2011, to Multi-Year Revolving Credit Agreement, dated as of June 30, 2010, among Questar Corporation, as borrower, Wells Fargo Bank, National Association, as administrative agent, Bank of America, N.A., JPMorgan Chase Bank, Barclays Capital and Deutsche Bank Trust Company Americas, as syndication agents, and the lenders party thereto filed as Exhibit 10.1 to the Questar's Current Report on Form 8-K/A (Commission File No. 001-08796) filed December 14, 2011, and incorporated herein by reference.12.1**Questar Corporation ratio of earnings to fixed charges.12.2**Questar Pipeline Company ratio of earnings to fixed charges.12.3**Questar Gas Company ratio of earnings to fixed charges.31.1**Questar Corporation Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.2**Questar Corporation Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.3**Questar Pipeline Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.4**Questar Pipeline Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.5**Questar Gas Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.6**Questar Gas Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.7*Questar Corporation Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.8*Questar Corporation Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.  Questar 2011 Form 10-Q/A 2     31.9*Questar Pipeline Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.10*Questar Pipeline Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.11*Questar Gas Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.12*Questar Gas Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.32.1**Questar Corporation Chief Executive Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.2**Questar Corporation Chief Financial Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.3*Questar Pipeline Company Chief Executive Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.4**Questar Pipeline Company Chief Financial Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.5**Questar Gas Company Chief Executive Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.6**Questar Gas Company Chief Financial Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.101.INS**XBRL Instance.101.SCH**XBRL Taxonomy.101.LAB**XBRL Labels.101.PRE**XBRL Presentation.101.CAL**XBRL Calculations.101.DEF**XBRL Definitions.  *Filed herewith**Previously filed or furnished with the registrants Quarterly Report on Form 10-Q filed on November 4, 2011  Questar 2011 Form 10-Q/A 3       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 CORPORATION
QUESTAR PIPELINE COMPANY
QUESTAR GAS COMPANY
(Registrants)Date: December 15, 2011By:/s/ Ronald W. JibsonRonald W. JibsonPresident and Chief Executive Officer,
Questar and Questar GasDate: December 15, 2011By:/s/ R. Allan BradleyR. Allan BradleyPresident and Chief Executive Officer,
Questar PipelineDate: December 15, 2011By:/s/ Kevin W. HadlockKevin W. HadlockExecutive Vice President and Chief Financial Officer,
Questar, Questar Pipeline and Questar Gas   Questar 2011 Form 10-Q/A 4    INDEX TO EXHIBITS  Exhibit No.Description of Exhibit10.1*First Amendment, dated as of September 2, 2011, to Multi-Year Revolving Credit Agreement, dated as of June 30, 2010, among Questar Corporation, as borrower, Wells Fargo Bank, National Association, as administrative agent, Bank of America, N.A., JPMorgan Chase Bank, Barclays Capital and Deutsche Bank Trust Company Americas, as syndication agents, and the lenders party thereto filed as Exhibit 10.1 to the Questar's Current Report on Form 8-K/A (Commission File No. 001-08796) filed December 14, 2011, and incorporated herein by reference.12.1**Questar Corporation ratio of earnings to fixed charges.12.2**Questar Pipeline Company ratio of earnings to fixed charges.12.3**Questar Gas Company ratio of earnings to fixed charges.31.1**Questar Corporation Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.2**Questar Corporation Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.3**Questar Pipeline Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.4**Questar Pipeline Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.5**Questar Gas Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.6**Questar Gas Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.31.7*Questar Corporation Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.8*Questar Corporation Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.9*Questar Pipeline Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.10*Questar Pipeline Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.11*Questar Gas Company Chief Executive Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.31.12*Questar Gas Company Chief Financial Officer Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, dated December 15, 2011.32.1**Questar Corporation Chief Executive Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.2**Questar Corporation Chief Financial Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.  Questar 2011 Form 10-Q/A 5     32.3*Questar Pipeline Company Chief Executive Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.4**Questar Pipeline Company Chief Financial Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.5**Questar Gas Company Chief Executive Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.32.6**Questar Gas Company Chief Financial Officer Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, dated November 4, 2011.101.INS**XBRL Instance.101.SCH**XBRL Taxonomy.101.LAB**XBRL Labels.101.PRE**XBRL Presentation.101.CAL**XBRL Calculations.101.DEF**XBRL Definitions.  *Filed herewith**Previously filed or furnished with the registrants Quarterly Report on Form 10-Q filed on November 4, 2011   Questar 2011 Form 10-Q/A 6