SITE INFORMATION AND CORRESPONDENCE

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xylenes at o. 9 ppm and 8 . 3 ppm, respectively. It also states that a quarterly groundwater monitoring program should be initiated and a well should be installed closer to the fo er tank pit area. 12-22-89 Groundwater samples taken this date. Depth to water measurements were 23 . 06 ' , 2 2 .68 ' and 23 . 58 ' BGS for MW#1, MW#2 , and MW#3 , respectively. Gradient direction is to the North-North west, towards and slightly in between MW#1 and MW#2 . All three wle lls still show contamination, again with MW#2 showing the highest levels with benzene at 4 . 2 ppb. Gradient direction is consistent to the North-North west. 12-13-90 PHS/EHD sends letter to Gary Brophy advising that PHS/EHD is asking the CVRWQCB for official enforcement action. PHS/EHD also sends to the SWRCB a detailed description of site specific charges. 02-01-90 PHS/EHD receives first quarterly monitoring report. 03-09-90 PHS/EHD receives RB comments. RB would like a well closer to the former tank pit area to determine if the levels are such that would require active remediation, the existing wells are not, adequate for that purpose. 03-29-90 PHS/EHD sends letter to requesting an additional MW closer to the former tank pit area and further definition of the north, east and westerly borders of the contamination. Also states that the "headspace" method used for analysis is not sufficient to verify non detect conditions. Groundwater samples collected this date. Depth to water measurements show ground-water is still around 22 ' -23 ' BGS, similar' to the last sampling event. The only well to show contamination this round is MW#2 , with a benzene level of 44 . 0 ppb. 07-02-90 Depth to water measurements reveal that the watertable has dropped approximately 1' -2 ' BGS. Only 'MW#2 and MW#3 detected contamination this s round as TPH as diesel at 280 ppb and 480 ppb, respectively. Gradient is still consistent to the North-North West. 08-09-90 PHS/EHD sends RP enforcement letter requesting workplan for the groundwater inves igation. 10-o8-90 PHS/EHD sends RP second a forcemeat letter requesting a meeting.