NORTHWEST PIPELINE LLC — Warning Letter

520071012w_warning letter_07092007_text.pdf, page 1Official PDFS NT TO COMPLIANCE REGIS' E Hardcopy Electrontca y 4j Oa 0 of Copies&i Date O U. S Department of Transportation Pipeline and Hazardous Materials Safety Administration 12300 W Dakota Ave, SuIte 110 Lakewood, CO 80228 WARNING LETTER CERTIFIED MAIL - RETURN RECEIPT RE UESTKD July 9, 2007 Mr. Randy Barnard Vice President, Operations Northwest Pipeline Corporation 2800 Post Oak Blvd. , Mail Stop 21 Houston, TX 77056 CPF 5-2007-1012W Dear Mr. Barnard: During the week of May 21-27, 2007, a representative of the Washington Utilities and Transportation Commission (WUTC), pursuant to Chapter 601 of 49 CFR United States Code, conducted an inspection of Northwest Pipeline Corporation (WGP) Sumas District in and near Sumas, Washington. The WUTC acts as an agent of the Western Region, Pipeline and Hazardous Material Safety Administration (PHMSA). As a result of the inspection, it appears that you have committed probable violations of the Pipeline Safety Regulations, Title 49, Code of Federal Regulations. The items inspected and the probable violation(s) are: 1. $192. 467 External corrosion control: Electrical isolation. (c) Except for unprotected copper inserted in a ferrous pipe, each pipeline must be electrically isolated from metallic casings that are a part of the underground system. However, if isolation is not achieved because it is impractical, other measures must be taken to minimize corrosion of the pipeline inside the casing. (d) Inspection and electrical tests must be made to assure that electrical isolation is adequate.#

520071012w_warning letter_07092007_text.pdf, page 2The casing under the road crossing of Highway 99 for the 6" diameter Stanwood Lateral is shorted. WGP had previously installed a dielectric gel between the camer pipe and casing in an attempt to mitigate this short. However, the short still exists since both the earner pipe and casing having identical "structure-to-soil" readings of — 1. 095 Volts DC. The voltage test readings were obtained with a Cu/CuS04 half cell. The test data is listed below: Pipe (Volts) ~Costa Date Location 05/23/2007 6" Stanwood Lateral P/S of the 6" -1 095 line under Highway 99 Comments -1. 095 The casing was shorted. 2. $192. 479 Atmospheric corrosion control; General. (a) Each operator must clean and coat each pipeline or portion of pipeline that is exposed to the atmosphere, except pipelines under paragraph (c) of this section. (b) Coating material must be suitable for the prevention of atmospheric corrosion. (c) Except portions of pipelines in offshore splash zones or soil-to-air interfaces, the operator need not protect from atmospheric corrosion any pipeline for which the operator demonstrates by test, investigation, or experience appropriate to the environment of the pipeline that corrosion will— (1) Only be a light surface oxide; or (2) Not affect the safe operation of the pipeline before the next scheduled inspection. During the field inspection, the pipe coating at the "air-to-soil" transition had failed at two locations in the Mt. Vernon compressor station. Even though there were no signs of corrosion under the disbonded coating, the transitions need to be coated m order to prevent the possibility of external, atmospheric corrosion. Under 49 United States Code, ) 60122, you are subject to a civil penalty not to exceed $100, 000 for each violation for each day the violation persists up to a maximum of $1, 000, 000 for any 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 items identified in this letter. Failure to do so will result in Northwest Pipehne Corporation (WGP) 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 5-2007-1012W. Be advised that all material you submit in response to this enforcement action is sub3ect to bemg made pubhcly 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 beheve qualify for#

520071012w_warning letter_07092007_text.pdf, page 3confidential treatment redacted and an explanation of why you believe the redacted information qualifies for confidential treatment under 5 U. S. C. 552(b). Sincerely, j Chris oidal Director, Western Region Pipeline and Hazardous Materials Safety Administration CC: PHP-60 Compliance Registry PHP-500 T. Finch (¹118850) A. Rathbun, P. E. WUTC , D. Lykken, WUTC Joseph P. Robertson, P. E. , Williams Gas Pipeline#