Exhibit 5.01


                                                        Questar Corporation
                                                         180 East 100 South
                                                             P.O. Box 45433
                                                   Salt Lake City, UT 84145
                                                         Connie C. Holbrook
                                                     Senior Vice President,
                                                           General Counsel,
                                                    and Corporate Secretary



                                                               801 324 5202
                                                          Fax: 801 324 5483
                                                E-mail: ConnieH@questar.com


May 11, 2001

Questar Pipeline Company
180 East 100 South Street
P.O. Box 45360
Salt Lake City, Utah 84145-0360

Ladies and Gentlemen:

               Re: Questar Pipeline Company, Registration Statement on
          Form S-3 Relating to $250,000,000 Aggregate Principal Amount of
          Medium-Term Notes, Series B

     I am acting as counsel for Questar Pipeline Company, a Utah
corporation (the "Company"), in connection with the preparation of a
Registration Statement on Form S-3 to be filed by the Company with the
Securities and Exchange Commission (the "Commission") on the date of this
letter (the "Registration Statement"). The Registration Statement relates
to the issuance and sale from time to time, pursuant to Rule 415 of the
General Rules and Regulations promulgated under the Securities Act of 1933
(the "1933 Act"), of up to $250,000,000 aggregate principal amount of the
Company's Medium-Term Notes, Series B (the "Series B Notes") to be issued
pursuant to an indenture (the "Indenture") by and between the Company and
Wells Fargo Bank Northwest, National Association (formerly known as First
Security Bank, N.A.), as trustee (the "Trustee").

     This opinion is delivered in accordance with the requirements of Item
601(b)(5) of Regulation S-K under the 1933 Act, as amended.

                                    -2-

     In connection with this opinion, I have examined and am familiar with
originals or copies, certified or otherwise identified to my satisfaction,
of such documents, agreements, certificates and corporate or other records
as I have deemed necessary or appropriate as a basis for this opinion. This
includes: (i) the Registration Statement (together with the form of
preliminary prospectus that is a part of it) in the form to be filed by the
Company with the Commission on the date of this letter; (ii) the Indenture;
(iii) the form of the Series B Notes issuable under the Indenture; (iv) the
Form T-1 of the Trustee being filed with the Commission as Exhibit 25.01 to
the Registration Statement pursuant to the Trust Indenture Act of 1939, as
amended; (v) the Restated Articles of Incorporation and Bylaws of the
Company, each as amended through the date of this letter; (vi) resolutions
of the Board of Directors of the Company relating to the filing of the
Registration Statement and the proposed issuance of the Series B Notes; and
(vii) the form of Distribution Agreement to be entered into among the
Company, Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith
Incorporated, Banc of America Securities LLC, Banc One Capital Markets,
Inc., and U.S. Bancorp Piper Jaffray, and being filed as Exhibit 1.01 to
the Registration Statement. In my examination, I have assumed the
genuineness of all signatures, the legal capacity of all natural persons,
the authenticity of all documents submitted to me as originals, the
conformity to the original documents submitted to me as certified or
photostatic copies and the authenticity of the originals of such latter
documents. As to any facts material to this opinion that were not
independently established or verified, I have relied upon statements and
representations of officers and other representatives of the Company and
others.

     I am admitted to the Bar of the State of Utah, and I express no
opinion as to the laws of any other jurisdiction. To the extent that the
opinion set forth below relates to matters under the laws of the State of
New York, I have relied on the opinion of Skadden, Arps, Slate, Meagher &
Flom LLP, special counsel for the company, which is being filed as Exhibit
5.02 to the Registration Statement.

     Based on and subject to the foregoing, I have formed the following
opinion: When (1) the Registration Statement has become effective under the
1933 Act, (2) the definitive terms of the Series B Notes and of their issue
and sale have been duly established in conformity with the Indenture so as
not to violate any applicable law or agreement or instrument then binding
on the Company, and (3) the Series B Notes have been duly executed and
authenticated in accordance with such Indenture and have been issued and
sold as contemplated in the Registration Statement, the prospectus
contained in it and any supplement (the "Prospectus"), the Series B Notes
will constitute valid and legally binding obligations of the Company,
entitled to the benefits provided by the Indenture and enforceable against
the Company in accordance with their terms, except to the extent that
enforcement may be limited by (a) bankruptcy, insolvency, fraudulent
transfer,

                                    -3-

reorganization, moratorium or other similar laws now or hereafter
in effect relating to creditors' rights generally and (b) general
principles of equity (regardless of whether enforceability is considered in
a proceeding at law or in equity).

     I further consent to the reference made to me under the heading "Legal
Matters" in the Prospectus and the filing of this opinion as Exhibit 5.01
to the Registration Statement. In giving such consent, I do not admit that
I am in the category of persons whose consent is required under Section 7
of the 1933 Act.

                               Sincerely,


                               /s/  Connie C. Holbrook
                               ---------------------------------------
                                    Connie C. Holbrook
                                    Questar Corporation
                                    Senior Vice President, General Counsel,
                                    and Corporate Secretary