Laserfiche WebLink
MONITORING PROGRAM <br /> Water quality is monitored in accordance with WDR Order No. 5-01-176 and the monitoring <br /> program approved by the Regional Water Quality Control Board. <br /> Water purged from wells prior to sampling is disposed of to the ground around the wells away <br /> from surface drainage features. This is a common practice when the water sampled is non-toxic, <br /> as at the CHSL. Purging and sampling procedures are described in Appendix A. <br /> Progress of Corrective Action Measures is submitted twice yearly(during 1St and 3rd quarters), <br /> which documents the effectiveness of current corrective action measures. <br /> Groundwater <br /> The groundwater monitoring network consists of seven monitoring wells. In January 2006, all <br /> wells were resurveyed based on the NAVD88 control rather than MSL. Top of Casing(TOC) <br /> elevations have been changed on Tables 1 and 2 to correspond with the new surveyed elevations. <br /> Shallow Aquifer Monitoring <br /> Three wells (SB-1, MW-4 and MW-5)monitor the shallow aquifer perched on the Corcoran clay <br /> layer east of the landfill. The Corcoran Clay pinches out to the west of these wells as shown on <br /> Figure. Well SB-1 is an up-gradient well, whereas wells MW-4 and MW-5 are down-gradient <br /> wells. Piezometer PZ-1 is used to measure the shallow aquifer elevation; however, recent <br /> soundings have not detected water in PZ-1. Flow in the shallow aquifer is historically bi- <br /> directional from SB-1 (Figure 2). <br /> Deep Aquifer Monitoring <br /> The dee aquifer is monitored b MW-6 down adient and MW-7 u adient). <br /> p q Y ( �' ) ( per <br /> Groundwater samples are analyzed for the following quarterly field and monitoring parameters as <br /> specified in WDR Order No. 5-01-176: <br /> ' Groundwater Elevation Total dissolved solids (TDS) <br /> Temperature Chloride <br /> Electrical conductivity Sulfate <br /> pH Nitrate-nitrogen <br /> Turbidity Volatile organic compounds <br /> Groundwater samples are analyzed annually for these additional parameters: <br /> Carbonate Magnesium <br /> Bicarbonate Potassium <br /> • Calcium Sodium <br /> ' Corral Hollow Landfill 4 Department of Public Works/Solid Waste <br /> 2nd Quarter 2007 Groundwater Monitoring County of San Joaquin—July 31,2007 <br />