Questar Gas 8-K Changes in Registrant's Certifying Accountant

Exhibit 16.1

Ernst & Young LLP Suite 400 178 South Rio Grande Street Salt Lake City, UT 84101 Tel: +1 801 350 3300 Fax: +1 801 350 3456 ey.com

September 22, 2016

Securities and Exchange Commission

100 F Street, N.E.

Washington, DC 20549

Ladies and Gentlemen:

We have read Item 4.01 of Form 8-K dated September 16, 2016, of Questar Gas Company and are in agreement with the statements contained in the second paragraph therein. We have no basis to agree or disagree with other statements of the registrant contained therein.

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