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• "Two parcels have been included in the investigation 198-120-08 main and 198-120-09 southern."Comment: It is not clear what is meant by the terms"main"and "southern." • Borings were advanced to depths of 15 to 25 feet bgs. • Groundwater grab samples were collected from 10 soil borings at depths of 6 to 10 feet bgs and 15 to 20 feet bgs from one boring. • "No hydrocarbon-like odors were observed in samples"and organic vapors were not detected using a PID greater than background values with the exception of one boring a five foot sample AB1 8-5 contained 0.6 ppmv organic vapors. • Constituents of concern were not reported at or above laboratory reporting limits in any of the analyzed soil samples collected from the borings. • A total of twenty-one (21) soil samples were analyzed from borings AB1 through AB7 for the TPH-d/o constituents listed. A total of fifteen (15) soil samples were analyzed from borings AB8 through AB21 for the TPH-gasoline, d/o constituents. Target analytes for semi-volatile organic compounds quantified as fuel oil, were not detected in any of the soil samples. • Fifteen soil samples were analyzed for CAM 17 metals. Arsenic was detected as high as 2.4 milligrams per kilogram (mg/kg), chromium as high as 7.5 mg/kg, cobalt as high as 11 mg/kg, copper as high as 21 mg/kg, lead as high 6.4 mg/kg, nickel as high as 12 mg/kg, vanadium as high as 36 mg/kg and zinc as high as 78 mg/kg.Additional "analytes of concern"were non-detect. Metal concentrations were indicated to be background levels and were less than their respective TTLC concentrations. • A total of five (5) grab groundwater samples were collected from borings AB 1 through AB7 and four (4) from collected from borings AB8 through AB16' [wording is unclear about how five samples can be collected from seven borings and four samples were collected from nine borings and the conclusions section is also confusing stating nine groundwater samples were collected from borings 131 through B5 and four groundwater samples from AB1 through AB21, inconsistent with earlier wording] are non detect for `fuel oils (diesel range compounds and fuel range hydrocarbons." Four grab groundwater samples were analyzed for CAM 17 metals with chromium detected as high as 0.014 milligrams per liter (mg/L), copper as high as 0.018 mg/L, nickel as high as 0.018 mg/L,vanadium as high as 0.073 mg/L and zinc as high as 0.049 mg/L. • Volatile organic compounds (VOCs) were not detected in the groundwater samples and "additional analytes of concern"were non-detect. AGE provided the following conclusion in their report: "Based on the findings of the environmental activities recounted in this report and results of the investigation, soil and groundwater at the site appears to be adequately assessed and not negatively impacted by historical site usage. Therefore, AGE does not recommend additional environmental investigations at this time." Comments: This PSA report consisted of advancing "soil" borings and although not known, it appears the investigation initially focused on evaluating potential petroleum hydrocarbon contamination. Typical standard of care for such "PSA"reports includes preparing summary tables of analytical data. Based on the absence of analytical data summary tables, combined with inconsistencies in the wording in the document related to the number of samples collected from borings and boring nomenclatures, it is difficult to evaluate the adequacy of the sampling and analytical Ninyo&Moore 1 500 E.Louise Avenue,Lathrop,San Joaquin County,California 1 104690095 1 August 11,2017 20