Laserfiche WebLink
' roolo ica(TechnicsInc. <br /> g Page 9 <br /> Site Conceptual Model <br /> Project No. 989.2 <br /> December 17, 2003 <br /> i <br /> ' 4.3 Climatic Summary <br /> ' Average Temperature: 62° F <br /> Average High Temp: 740 F <br /> Average Low Temp: 4$° F <br /> ' Highest Recorded Temp: 114° F <br /> Lowest Recorded Temp: 16° F <br /> Average Relative Humidity (Morning): 76% <br /> Average Relative Humidity (Afternoon): 45% <br /> Average Dew Point 46° F <br /> Average Rainfall: 13.7 inches <br /> Average Annual Wind Speed 8.3 mph <br /> i <br /> ' 4.4 Geological Summary <br /> The site map included as Figure 2 shows two lines of section corresponding to cross sections; <br /> ' Figures 4: Lithology of cross section A-A' and Figure 5: Lithology of cross section B-B'. <br /> Monitoring well and soil boring locations as well as the location of the former USTs are <br /> specified on the site map (Figure 2). Borehole logs are included in Appendix B. <br /> The shallow geology of the site is characterized b three distinguishable units. <br /> Y � <br /> * Clays and silts dominate the site between the surface and approximately 22 feet below <br /> ' grade. This unit is generally brown to dark brown in color with organic material present. <br /> Some small amounts of sands were noted in some samples. The dominant Lithology of <br /> this unit however is characterized by clays and silts. <br /> a Dirty sand best describes the unit between 22 and 30 feet bgs. Tan to brown in color, <br /> this sand unit contains varied amounts of fines. <br /> • A blue clay unit appears at approximately 30 feet bgs and contains some occasional <br /> sands. The clay is plastic and may impede downward migration of contaminants. <br /> 4.5 Groundwater Parameters <br /> A summary of groundwater parameters is included as Table 5 in Appendix A. <br /> ' 1. Dissolved oxygen readings over the last quarter have ranged between 0.38 and 3.85 ppm. <br /> This range is advantageous to promoting biodegradation activity. <br /> 2. Oxidation-reduction potential at the site is generally positive. Negative values have been <br /> recorded at the site. <br /> 3. The measured pH in the groundwater monitoring wells range between 7.6 and 8.2. This <br /> pH range is conducive to maintaining aerobic biodegradation activity. <br /> 4. Conductivity readings gathered during groundwater monitoring events are inconclusive. <br /> Measurements taken during the last quarter range from 944 to 1920 UmMHOS. <br /> 1 ' <br />