SITE INFORMATION AND CORRESPONDENCE

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This statement is false. The CRWQCB failed to notice well MW-3B contained 7,400 micrograms per liter(ug/L) and the concentrations at well MW-4B are most likely attributed to lateral not vertical migration. Well MW-3B is located 20 feet from the Site's USTs and the concentrations found in well MW-4B, located in the same B depth zone and located approximately 215 feet down gradient,had MTBE concentrations of 360 ug/L. Based on groundwater level data collected during the last 6 quarterly monitoring events, a downward vertical flow component exits at the well MW-3 A and B nested location on site but a consistent upward vertical gradient exists at the well MW-4 A and B nested location. An upward vertical gradient is also seen at the well MW-5A and B nested well location. A downward vertical gradient is seen between the well MW- 6B and C nested well location but well MW-6C has never had a detection of MTBE. The well MW-9B, C, and D well nest shows an upward vertical gradient during the single sampling event performed on September 20,2006. One quarters data is not conclusive and additional tests are needed. Page 4,Item 12—The CRWQCB states that MTBE was detected in well MW-6B at 160 ug/L and well MW-6B is screened from 25-to 50-feet bgs. The actual MTBE concentration at well MW-6B on March 30,2006 was 140 ug/L. Also, well MW-6B is screened from 40-to 50-feet bgs. Page 4,Item 16—The CRWQCB states that Apex refused to sample the CSA-31 Well 2 well on a weekly basis. Mr. Tom Landwehr stated in his email that Apex would sample the well on a bi-weekly basis. Apex received this letter on June 20,2006 and contated SJCEHD with the bi- weekly request. We did not hear from them and were notified by the CRWQCB on June 26, 2006. Apex implemented weekly sampling at that time. A sample was collected on June 28,2006 and July 14,2006. On June 7,2006,Apex met with County waste water personnel and was advised that the well was not operational. Page 5,Item 19—The dischargers have not demonstrated that an NPDES permit is the most cost effective method for the long term discharge of a groundwater pump and treatment remediation. Apex has evaluated other discharge options including discharge to ground surface and sewer discharge. The lawn area next to the remediation system is so saturated from minimal lawn irrigation and depth to groundwater is shallow, approximately 10-feet bgs. Therefore,discharge to ground surface is not a viable option. Apex contacted the local sewer authority and was denied discharge access. The current groundwater pumping and treatment system has reduced groundwater contamination from 210,000 ug/L to 33,000 ug/L at well EW-4. This order of magnitude reduction in MTBE concentrations proves the current system is a viable remediation system.