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Page 2 of 3 The map summarizes the WES data from 2003 (white circles) and 2008 (blue squares), and the draft proposed wells (yellow targets) are positioned according to the dissolved contaminants we saw in those borings (I downloaded the Google Earth photo). The contaminant plume seems to be moving northerly on the basis of the contaminant dissolved distribution(the water levels were not sufficient for a rough contour plot). Some separate phase was observed at B-5, B-10, B-11 and B-12, whether this is from the tank or pipeline source, I assume some pipeline might "drift" along to the north as well. Since the "deep" (30-34 feet deep) Hydropunchs at B-10 and B-12 did not show highly elevated TPHG or TPHD or BTEX/MTBE data, I propose monitoring well depths of about 25 feet and screened with 12 to 15 feet 0.020 slot (ie, between about 25-15 feet more or less) in each well for water level fluctuations and to observe for presence of product. Our 2008 data shows limited dissolved TPHG and TPHD, with the highest levels assumed corresponding to the separate phase we saw; really no Benzene or MTBE. I initially suggest that we monitor quarterly for TPHG, TPHD, BTEX MTBE plus 4, 12DCA and EDB to address City former UST. I see no reason to monitor for Ethanol and Methanol since we did not detect it. Chevron data seems pretty much in line with ours, I thought I saw one large hit of Ethanol but not sure why, perhaps a spike of theirs? They stated that they were looking for more for raw petroleum rather that "fuel" contaminants so perhaps the data are slightly different. We can discuss with them. The separate phase is probably fairly well spread about the site and if Chevron source, not sure what the cleanup approach is and what Chevron is to do. Suggest we install wells and then we/City discuss with Chevron their data, the recurring parking lot surface seeps and cleanup approach-possibly risk assess with groundwater monitoring as with other similar high TPH low fuel VOA sites as you had mentioned? I'll be back from New Mexico on Friday we can discuss further if needed. Chris Palmer for Wright Environmental Services Inc. ph 408/267-5238 "CONFIDENTIALITY NOTICE" - This message and its attachments are addressed solely to the persons above and may contain privileged and confidential attorney/client communication. If you have received the message in error, the distribution or dissemination of content hereof is prohibited. Please return it immediately to the sender and please delete the message from your system. The sender or the sender's client or principal does not intend by this communication to conduct a transaction or make any agreement by electronic means. Nothing contained in this message or in any attachment shall satisfy the requirements for a writing, and nothing contained herein shall constitute a 1/7/2009