DOMINION ENERGY QUESTAR PIPELINE, LLC — Warning Letter

520151007W_warning letter_06232015_text.pdf, page 1Official PDFWARNING LETTER CERTIFIED MAIL - RETURN RECEIPT REQUESTED June 23, 2015 Mr. Ron Jorgensen Vice President – Operations and Gas Control Questar Pipeline Company 333 South State Street P.O. Box 45360 Salt Lake City, UT 84145-0360 CPF 5-2015-1007W Dear Mr. Jorgensen: Between April 28, 2014 and September 12, 2014, representatives of the Pipeline and Hazardous Materials Safety Administration (PHMSA) and the Arizona Corporation Commission (ACC), pursuant to Chapter 601 of 49 United States Code, inspected the Questar Pipeline Company’s (Questar) Southern Trails Pipeline system (GTN) in the states of Arizona, California, New Mexico, and Utah. As a result of the inspection, it appears that you have committed a probable violation of the Pipeline Safety Regulations, Title 49, Code of Federal Regulations. The items inspected and the probable violation is: 1. §192.743 Pressure limiting and regulating stations: Capacity of relief devices. (a) Pressure relief devices at pressure limiting stations and pressure regulating stations must have sufficient capacity to protect the facilities to which they are connected. Except as provided in §192.739(b), the capacity must be consistent with the pressure limits of §192.201(a). This capacity must be determined at#

520151007W_warning letter_06232015_text.pdf, page 2intervals not exceeding 15 months, but at least once each calendar year, by testing the devices in place or by review and calculations Questar could not provide documentation that the capacity of relief devices required by Section 192.603(b) was reviewed and calculated once each calendar year, not to exceed 15 months, in accordance with Section 192.743(a). Documentation was not available to demonstrate that the relief valve capacity calculation review had been conducted during the 2013 calendar year for the Tuba City meter station. The records for the relief valve capacity calculation at the Tuba City meter station revealed the 2012 annual review was conducted on October 03, 2012 and the subsequent annual review was conducted on January 27, 2014. Under 49 United States Code, §60122, you are subject to a civil penalty not to exceed $200,000 per violation per day the violation persists up to a maximum of $2,000,000 for a related series of violations. For violations occurring prior to January 4, 2012, the maximum penalty may not exceed $100,000 per violation per day, with a maximum penalty not to exceed $1,000,000 for a related series of violations. We have reviewed the circumstances and supporting documents involved in this case, and have decided not to conduct additional enforcement action or penalty assessment proceedings at this time. We advise you to correct the item(s) identified in this letter. Failure to do so will result in Questar Pipeline Company being subject to additional enforcement action. No reply to this letter is required. If you choose to reply, in your correspondence please refer to CPF 5-2015-1007W and for each document you submit, please provide a copy in electronic format to PHP-WRADMIN@dot.gov whenever possible. Be advised that all material you submit in response to this enforcement action is subject to being made publicly available. If you believe that any portion of your responsive material qualifies for confidential treatment under 5 U.S.C. 552(b), along with the complete original document you must provide a second copy of the document with the portions you believe qualify for confidential treatment redacted and an explanation of why you believe the redacted information qualifies for confidential treatment under 5 U.S.C. 552(b). Sincerely, Chris Hoidal Director, Western Region Pipeline and Hazardous Materials Safety Administration cc: PHP-60 Compliance Registry PHP-500 H. Nguyen ACC (#146202)#