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Crealogicol7-"knics tw Page 3 Groundwater Monitoring Report Project No 723 2 . March 21,2005 1 As previously reported by GTI, the CMTS wells were so tightly coiled for shipping that it was difficult to install the wells without the tubing corkscrewing in the borehole, even when ' the casing was stretched out on the ground in the sun to warm and relax the coils The result Of this twist in the tubing is that depth to water measurements could not be made because the ' instrument probe becomes lodged in the small chambers of the tubing But Del-Tech Geotechnical Support has procured a new micro-water level meter that can be used in the CMTTM wells The first quarter of 2005 was the first time that the well chambers were ' sounded i The ability to sound the wells resulted in changes in this and future quarterly monitoring ' reports The wells were grouped according to the aquifer interval that the screened section intercepted (see Figure 14 for well screen intervals) ' Shallow Wells (screened 35 —55 feet bgs) MW-4, 5, 6, 7, 8 & 9 j Intermediate Wells (screened 43 --70 feet bgs) MW-1, 2, 3, 107, 108 & 109 j Deep (screened 76— 80 feet bgs) MW-207, 208 & 209 ' Deepest Wells (screened 94—97 feet bgs) MW-101, 307, 308 & 309 The aquifer was divided in four horizons based on the screened intervals and groundwater gradient contour maps constructed for each horizon shallow, intermediate, deep and deepest 1.1 Hydrogeology of Site ' Horizontal Groundwater Gradients The calculated gradients for the January 2005 monitoring event are as follows ' 1 Water table wells screened 35 to 55 ft bgs 0 0051 ft/ft N580E 2 Intermediate wells screened 43 to 70 ft bgs 0 0060 ft/ft N55°E ' 3 Deep wells screened 76 to 80 ft bgs 0 0076 ft/ft N680E 4 Deepest Wells screened 94 to 97 ft bgs 0 0057 ft/ft S75°E Figures 2A through 2D illustrate four aquifer groundwater gradient maps for the January 2005 event Figure 3, Groundwater Gradient Rose Diagram, includes the historical shallow groundwater directions and gradients Tables 1 —4 in Appendix A contain the groundwater elevations and gradients for the site Vertical Groundwater Gradients Under vertical groundwater flow conditions, the water level in a monitoring well is a function ' of the length of the well screen and its depth or vertical position in the aquifer As with horizontal flow conditions, the diameter of the well or piezometer is immaterial A vertical gradient was calculated for the well pair MW-3/MW-201 and for the first time the MW- 8/MW-108 and MW-108/MW-208 well pairs