SITE INFORMATION AND CORRESPONDENCE

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Mr. David Johnson • -2- . 20 May 2011') Herman and Helen's Marina Monitoring well MW-2 contained the greatest concentrations of total petroleum hydrocarbons as diesel (TPHd) at 3,700,000 micrograms per liter (pg/L), a concentration that is indicative of liquid phase hydrocarbons (LPH, i.e., "free product"), and TPH as gasoline (TPHg) at 110,000 pg/L. The MRP requires "Monitoring wells with free phase petroleum product or visible sheen shall be monitored, at a minimum, for product thickness and depth to water." Based on our review of AGE's Monitoring and Sampling Procedures and field logs in the Fourth QMR, it does not appear that AGE is monitoring for LPH. Extraction well EW-1 contained the greatest concentration of tertiary butyl alcohol (TBA) at 43,000 ug/L and MW-4 contained the greatest concentration of methyl tertiary butyl ether (MTBE) at 24 pg/L. Fourth quarter TBA concentrations in EW-1 increased compared to the previous quarter. AGE performed first quarter monitoring on 30 March 2011 and depths to groundwater ranged from less than 1 foot to about 24 feet with the flow to the southeast and gradient ranging from 0.012 ft/ft under the flat portion of the Site to 0.24 ft/ft beneath the levee. AGE could not sample four wells due to a damaged well casing at MW-9; inaccessibility of MW-8 and MW-10; and insufficient groundwater in MW-13. Monitoring well MW-2 contained the greatest concentrations of TPHg and TPHd at 4,400 pg/L and 7,900 pg/L, respectively, and contained elevated concentrations of ethylbenzene, toluene, and total xylenes. Extraction well EW-1 contained the greatest concentration of TBA at 16,000 pg/L, the third consecutive quarter that H&H has detected TBA in this well. Historically, it has been absent. Monitoring well MW-4 contained the greatest concentration of MTBE at 16 pg/L. I contacted AGE to inquire whether the surface seal at MW-9 had been compromised, and for additional information regarding inaccessibility at MW-8, MW-10 and MW-12. AGE informed me by email that they do not believe the seal had been compromised when it sustained damage during construction activities. They have a flush surface completion at MW-9 but continued access requires installation of a stove-pipe completion. Alternatively, they recommend abandoning this well, which is presently covered in sediment and weeds. Wasps have infested MW-8 and MW-10 making them inaccessible. Someone parked a car over MW-12 but AGE could not find the owner to remove it before completing the monitoring event. The MRP requires H&H to sample two drainage ditch locations (DDN and DDS) quarterly, to evaluate the impact of discharge from the IRM on surface water. However, H&H discontinued use of the IRM in June 2009 and has only sampled the surface water locations sporadically. During the first quarter, AGE collected surface water samples DDN and DDS for the first time since April 2010 and the analyzed constituents were below detection limits. Both the Fourth and First QMRs recommend meeting with Central Valley Water Board staff to discuss reducing the groundwater monitoring frequency, and accelerating site closure. The First QMR recommends discontinuing surface water sampling. We have the following comments. 1. We are willing to arrange a meeting with H&H. However, our primary concern is H&H's lack of progress toward performing the ORC pilot study as discussed during our 18 May 2010 meeting and not reducing the groundwater monitoring frequency and accelerating site closure. While we may be able to revise the monitoring schedule at some sampling