Laserfiche WebLink
' eo(v tta[Technws Inc <br /> � B Page 2 <br /> Groundwater Monitoring Report <br /> Project No 662 2 <br /> .lune 12, 2001 <br /> ' 1.0 GROUNDWATER MONITORING <br /> ' 1.1 Hydrogeology of Site <br /> The dominant soil type in the upper 40 feet of subsurface geologic soils investigated is fine <br /> ' to course grained sand alternating with plastic clays The average groundwater elevation on <br /> February 16, 2001 was approximately IS 16 feet above MSL, which is about 21 feet below <br /> ground surface <br /> ' A groundwater gradient was calculated for the April <br /> 2001 monitoring event and found the <br /> ' groundwater to be flowing N2°W at 0 01S ft/ft Groundwater elevation and gradient data <br /> are summarized in Table 1, Appendix A Gradient direction is shown on Figure 2 Gradient <br /> Map, and Figure 3 Groundwater Gradient Rose Diagram <br /> ' 1.2 Groundwater Sampling Procedure <br /> ' On April 27, 2001, Don Light of Del-Tech mobilized to the site to conduct a groundwater <br /> monitoring of the three existing monitoring wells on site <br /> Before sampling was performed the wells were sounded for depth to water and then a clear <br /> disposable bailer was used to determine if floating product was present The wells were <br /> purged of at least three well volumes of stagnant water using a dedicated Waterra check-ball <br /> assembly and r/2 inch tubing Purging continued until the temperature, conductivity, and pH <br /> of the groundwater stabilized (<10% variation between three readings) indicating that <br /> formation water representative of aquifer conditions was entering the wells These water <br /> ' duality parameters were measured at intervals of each well volume purged <br /> ' Once purging was complete, a water sample was collected from the Waterra tube Care was <br /> taken to minimize sample agitation Once the sample container was filled and capped, the <br /> bottle was inverted, tapped, and checked for headspace bubbles The sample container was <br /> ' identified and labeled with a unique designation, inserted into foam holders and placed in an <br /> ice chest cooled to 4°C for transport to the laboratory <br /> ' All non-disposable sampling equipment was decontaminated using a hot water washer and <br /> detergent before and between uses Disposable gloves were used by the technician to <br /> collect all samples and were changed with each sample collection <br /> ' A chain of custody document, listing all samples collected, accompanied the samples from <br /> field to laboratory, thereby providing a means to track their movement and insure their <br /> ' integrity <br />