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Page 4 Cabral—Mc Adams Property April 28,2006 Job No. 1828-092.01 October 2005 Soil Sampling Pursuant to the recommendations of our referenced Phase I Environmental Site Assessment, on October 20, 2005 two soil borings (Borings B1 and B2) were advanced to a depth of 20 feet within the area of previously removed underground storage tank (see Plate 2); apparent backfill materials consisting of brown silty fine sands with gravel were encountered to a depth of about eight feet in each of these borings. No obvious evidence of contamination was observed in Boring B 1. A petroleum odor was evident in soils encountered within Boring B2 from a depth of about ten feet to our maximum 20-foot exploration depth. Subsurface soil samples collected from each boring at depths of 10-, 15-, and 20 feet were submitted for laboratory analysis. The results of the laboratory testing indicated that the soil samples collected from depths of 15 and 20 feet from Boring B2 contained significant concentrations of gasoline-range petroleum hydrocarbons. Because elevated concentrations of gasoline—range petroleum hydrocarbons were detected at Boring B2 during our October 2005 investigation, we recommended additional soil sampling to further characterize the lateral and vertical extent of soil contamination within the area of the former underground tank. Our firm prepared a Workplan for additional environmental investigation dated February 28, 2006.2 A copy of our Workplan was presented to the SJCEHD for review and comment. March 2006 Soil Sampling On March 29, 2006, five additional soil borings (Boring B3 through B7) were advanced within the former underground tank area (see Plate 2). One of the borings (Boring B3) was advanced very near Boring B2 where subsurface petroleum hydrocarbon contamination was encountered during the October 2005 sampling. Boring B3 was advanced to a depth of 40 feet. A petroleum hydrocarbon odor was evident in the soils encountered in Boring 3 at depths between ten and 20 feet, and by 25 feet had dissipated significantly. Soil samples at depths of 25, 30, 35 and 40 feet were collected from Boring B3 and submitted for laboratory analysis. Borings B4 through B7 were advanced at locations peripheral to the former underground tank location; each of these borings was advanced to a depth of 30 feet; no evidence of petroleum hydrocarbon contamination was observed by our representative in any of these borings. Soil samples were collected at depths of 15, 20, and 30 feet from Boring B4 and at depths of 10, 20, and 30 feet for Borings B5 through B7, and submitted for laboratory analysis. LABORATORY ANALYSIS The subsurface soil samples from the area of the former underground storage tank area were analyzed for one or more of the following: total petroleum hydrocarbons (TPH) as gasoline, TPH as diesel, benzene, ethylbenzene, toluene, and xylenes (BTEX), and methyl tert-butyl ether (MTBE). The results of the soil analyses are summarized on the attached Table 1. Copies of the laboratory reports and chain-of-custody documentation are appended. 2 Raney Geotechnical, Inc., "Workplan, Additional Environmental Investigation, Cabral Property, APNs 115-230- 06, and-07,4202 through 4208 Sutter Street, Stockton, California"; February 28,2006,Raney Reference No. 1828- 092.01.