Laserfiche WebLink
a <br /> a <br /> C40togicat?-ecfinics lac. <br /> 1101 7`"Street <br /> Modesto,California 95354 <br /> (209)522-41191 Fax(209)522-4227 <br /> ' REPORT <br /> ' Groundwater Monitoring <br /> 3rd Quarter 2004 <br /> ' Sinclair Trucking <br /> 3780 West Linne Road <br /> Tracy, California <br /> ' <br /> Project No. 1030.2 <br /> October 29, 2004 <br /> EXECUTIVE SUMMARY <br /> This report summarizes the 3`d Quarter 2004 round of groundwater monitoring and testing <br /> ' that took place on July 14, 2004. The laboratory analyses indicate that detectable <br /> concentrations of the aromatic hydrocarbon compounds (BTEX) and gasoline range <br /> petroleum hydrocarbons (TPH-G) are present in MW-1. Traces of some constituents were <br /> ' detected in MW-4. The domestic well and the remaining four of the sites six monitoring <br /> wells were below laboratory detection limits for all analyzed constituents. <br /> ' PIots of TPH-G&Elevation versus Time: MW-1 (Chart 1) TPH-G &Elevation versus Time: <br /> MW-4 (Chart 2) indicate the concentrations of TPH-G rise with increasing groundwater <br /> elevation suggesting residual LNAPL changes to the dissolved state when in contact with <br /> ' groundwater. The average groundwater elevation recorded during the July 2004 <br /> groundwater-monitoring event is 67.56 feet above mean sea level. Site-specific gradient <br /> calculations show groundwater flowing N40°E with a slope of 0.0042 ft/ft. <br /> 1.0 HYDROGEOLOGIC SYSTEM <br /> 1.1 Regional Structure <br /> tSinclair Trucking (ST) is located in the southeast quarter of the northwest quarter of Section <br /> 7, T3S, R6E, related to the Mount Diablo B&M, on the United States Geological Survey <br /> (USGS) Topographic Map, Vernalis Quadrangle, California, 7.5 minutes series. A review of <br />