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laboratory data generated for the current monitoring period are generally acceptable and the water quality samples collected from the French Camp Landfill appear to be representative of water quality at the site. 4.3 GROUNDWATER ELEVATIONS AND CONTOURS Prior to purging and sampling, each well was sounded for water depth using a weighted electronic sounder, and the static water level was recorded on a Well Data Sheet (Appendix Q. The groundwater elevations were calculated for each well by subtracting the depth-to-water measurement from the top-of-casing reference elevation. The current and historical groundwater elevation data for the French Camp Landfill is summarized in Table 5. The groundwater elevation data obtained during the monitoring period were used to generate the groundwater elevation contour maps shown on Figures 1 and 2. During the first quarter 2011 (Figure 1 A) groundwater flowed to the east-northeast with an average hydraulic gradient of 0.001 ft/ft. During the second quarter 2011 (Figure 1 B) groundwater flowed to the northeast with an average hydraulic gradient of 0.005 ft/ft. To calculate the approximate linear groundwater flow velocity for the site, conservative assumptions were used, including a hydraulic conductivity of 300 gallons per day per square foot(0.014 cm/sec), and an estimated effective porosity of 35 percent (CH2M Hill 2000). An estimated range in groundwater flow velocity was calculated using Darcy's Law: (( . r�i r.•nt 0.005 sec- 11 t' = - = 0014 .. )* -. 1* 2835 -� fi- -- -_ 0.57 fi clay, Ene sec 0,35 em - rliiv where: V=Groundwater flow velocity. K=Hydraulic conductivity of the water-bearing unit(0.014 cm/sec). i=Maximum hydraulic gradient: i-0.005 for the site during the monitoring period. ne=Effective porosity(n,=0.35);an estimated value. The groundwater flow rate is calculated to be 0.57 feet/day (207 feet/year). 4.4 DETECTION MONITORING PROGRAM Field and laboratory results for DMP monitoring wells (MW-6A,MW-7A, MW-8A, MW-9A, MW-9B, and MW-lOA)from the current monitoring period are summarized in Table 2. During the monitoring period, no VOCs were detected in any of the groundwater monitoring wells at the French Camp Landfill. Concentration Limits For DMP monitoring wells at the French Camp Landfill, concentration limits (CLs) as established in the WDRs are used for the water quality protection standards (WQPS). Based on a comparison of the data obtained during the current monitoring period, the following analytes were found to exceed a CL: MUM 1-0051TC_1SAI Ldoex 3 GeoLoglc Associates