SITE INFORMATION AND CORRESPONDENCE

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0 i Ms. Wendy Cohen,P.E. r Page 3 of 5 _ _ December 29 2009 The typical percentages by volume of the products transported through the pipeline during 2009 have been: Gasoline 68% Diesel 28% ]et Fuel QP-5 only) 4% According to SFPP's Operation personnel at the Fresno Terminal, these percentages are consistent with historical percentages. integrity.. Internal line inspections (ILI), or smart pig tests, are conducted at least every 5 years on the line, including most recently in 2009 and 2004. The tests included an initial caliper pig test that gauges the inside pipeline diameter, and then a more sophisticated pig that measures geometry (deformation) and metal loss (thickness deviations away from initial). None of the tests has indicated integrity issues. Also, SFPP` has no indications of historical repairs or condition problems along this section of the line. A memorandum prepared by SFPP's Manager of Pipeline Integrity, Mr. Christopher Langan, that provides additional detail about the pipeline's condition is included with this letter as Attachment B. Mr. Langan's letter refers to stations 590+00 to 670+00, which covers an approximate 1.5 mile segment of the line, from 0.4 miles northwest and 1.1 miles southeast of the Site. SUBSURFACE CONDITIONS ARE NOT CONSISTENT WITH A RELEASE FROM THE SFPP PIPELINE The nature of hydrocarbons noted in soil boring M144-6 and the nature and extent of hydrocarbons across the remainder of the Site are not consistent with conditions that would be expected if sourced from the SFPP pipeline for three primary reasons: 1. The Hydrocarbons Are Not Consistent with the Materials Carried In the SFPP Line. The majority of the hydrocarbons carried in the line (more than 2/3 by volume) is gasoline. The material identified in MH4-6 was mostly a narrow hydrocarbon mixture between normal carbons C11 and C15 - - gasoline typically ranges between normal carbons C4 and C12. Since there have been no known SFPP releases in this area, the characteristics of a release from this line that may have been undetected during integrity tests would have been a long, slow release,which would have created a mix of gasoline, diesel,and jet fuel compounds in the subsurface. 2. The Common Indicators (BTEX and Fuel Oxygenates) at SFPP Release Sites Do Not Predominate. The typical indicators of SFPP release sites are elevated concentrations of BTEX, and if of the 1990's era, a significant plume of the fuel oxygenate MTBE. The maximum BTEX detection at this Site was only 7.1 mg/kg,and there has not been an indication of MTBE or other oxygenates. 3. The Distribution of the Hydrocarbons is Not What Would be Expected from a Release from the SFPP Pipeline. Refined hydrocarbons were not observed in soil boring MH4-7, located the same distance from the SFPP pipeline as NH4-6 (20 feet southwest). A release from the SFPP pipeline would not be expected to be seen at one of these two borings and not the other, when they are only 80 feet apart. Also, the local groundwater flow is to the northeast, yet hydrocarbons were not detected in the one soil boring located downgradient of the SFPP pipeline, soil boring GP-171.