SITE INFORMATION AND CORRESPONDENCE

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I n Mr Nathan Crum - 2 n25 i ` 25 July 2007 Valley Pacific Petroleum Services. Inc ' thickness was 0.1 1 feet in MW-8 during July 2006. GZA installed a Keck "Spoiler' hydrocarbon recovery skimming system was installed in MW-8 to automate SPH removal. However. due to malfunctions that caused the "Spoiler" to remove only groundwater from the well, GZA continues to manually remove SPH from well MW-8 by periodic bailing. GZA removed about 64.5 gallons of free product/water mixture from MW-8 during 2006 for a total of about 552 gallons since April 1994. Laboratory analyses for the constituents of concern (CDCs) at this Site include EPA Method 8021B for benzene. toluene, ethylbenzene, and xylenes (BTEX), EPA Method 8015M for total petroleum hydrocarbons as gasoline (TPHg) and diesel (TPHd), and EPA Method 8260M for gasoline oxygenate additives. In 2006, maximum concentrations of TPHg and benzene were in monitoring well MW-6R at 6.600 micrograms per liter (pg/L) and 1,400 pg/L, respectively. The maximum concentration of MTBE was in MW-7 at 11 ,000 pg/L. These wells in which SPH and elevated dissolved product were detected are consistent with historical results. The Second Semi-Annual Report describes groundwater monitoring and sampling activities performed during January and April 2007. GZA observed that DTW ranged from about 51 feet bgs during the January 2007 to about 55 bgs during April 2007. Groundwater flow during this period was toward the southwest and southeast at gradients ranging from about 0.004 ft/ft to 0.017 ft/ft. The DTW observations and gradient calculations are consistent with historical observations. GZA continues to manually remove SPH from well MW-8 and MW-9R by periodic bailing. GZA estimates that about 4.25 gallons of free product/water mixture were removed from MW-8 and 3.25 gallons from MW-9R during 2007. In January and April of 2007, maximum concentrations of TPHg and benzene were detected in monitoring well MW-6R at 4,700 pg/L and 580 pg/L, respectively. The maximum concentration of NFTBE was observed in MW-7 at 7,100 pg/L. These wells in which SPH and elevated dissolved product were detected are consistent with historical results. Our comments on the Reports are presented below. 1 It is unclear whether Valley Pacific is conducting monitoring and submitting the monitoring reports in accordance with the schedule required by MRP No. R5-2002-0827. Valley Pacific did not perform monitoring and reporting for the fourth quarter 2006. In addition, the MRP specifies that semi-annual reports shall be submitted to the Regional Board by 1 February for the third and fourth quarters and 1 August for the first and second quarters. Based on this schedule the Annual Report (First Quarter) was submitted on 8 February 2007. and the 15 May 2007 Semi-Annual Report was not due for submission until 1 August 2007. To ensure that site activities are understandable, please conduct future monitoring and reporting activities in conformance with the schedule in the MRP. 2 GZA reports that the SPH/groundwater mixture is stored on the Site in 55-gallon drums. Each future quarterly report must describe whether the drummed effluent remains on Site or provide the disposal schedule and location as the drums are removed from the Site. 3 The 25 January 2002 Deep Groundwater Monitoring Well Installation Report states that petroleum hydrocarbon contamination was discovered at the Site in 1985. Quarterly