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David Wang Page 8 "Volatile Organic Chemicals (VOCs) were not detected in wells 12447 or LM48 ; both were screened at depths greater than 120 feet (Table 1. 2-1) . This indicates that vertical contaminant migration has not extended deeper than approximately 110 feet within Area 2 . " This statement apparently is incorrect. PCE was detected at 2 . 1 ppb in MW-48, which is screened from 150 feet to 160 feet below ground surface. Clarification is requested. 5) paragraph 3 .4 . 4 . 4 . 3 , page 3-20, lines 8 to 10: The RI report states that groundwater samples collected from Well LM50 were 4 . 3 ppb PCE, and 6. 5 ppb TCE. The above information is inconsistent with Table 3 . 4-2 which reports 24 ppb TCE, and 21 ppb PCE from LM50 in 1988 . Clarification is requested. 6) page 3-20, paragraph 3 . 4 . 4 . 4 . 4 . , lines 1, 2 , and 3 : The RI report states: "Aromatic volatile organics (EPA Method 602) including benzene, toluene, ethylbenzene, and xylene were detected in the range of 1 to 20 ug/1 in Wells LM47 and LM52 . " The RI report should state whether any of these compounds were detected at levels above DHS action levels in Wells LM47 and LM52 . 7) Section 3 . 4 . 4 . 5 , Part 2 , Groundwater Monitoring Wells page 3-21, paragraph 3 . 4 . 4 . 5 . 3 , lines 2 and 3 : The RI report states: "Table 1.2-1 summarizes well construction details and the concentrations of PCE and TCE reported by laboratories. " The above statement is incorrect. Table 1. 2-1 does not include the concentrations of PCE and TCE reported by the laboratories. 8) page 3-22 , paragraph 3 . 4 . 4 . 5. 6, lines 2 , 3 , and 4 : The RI report states that 8 . 8 ppb PCE and 21 ppb TCE have been reported from analyses of groundwater samples from Well LM58 . Table 3 . 4-3 reports 35 ppb TCE and 17 ppb PCE from LM58 in 1988 . Clarification is requested. page 3-22 , paragraph 3 . 4 .4 . 5 . 7 , lines 1, 2 , and 3 :