ARCHIVED REPORTS_XR0012417 - Laserfiche WebLink

Home Browse Search

EGG Groundwater Sampling (GWS) ' Gregg In Situ, Inc conducts groundwater sampling using a HydropunctP type groundwater sampler, Figure GWS. The groundwater sampler has a retrievable ' stainless steel or disposable PVC screen with steel drop off tip This allows for samples to be taken at multiple depth intervals within the same sounding location In areas of slower water recharge, provisions may be made to set ' temporary PVC well screens during sampling to allow the drill rig to advance to the next sample location while the groundwater is allowed to infiltrate The groundwater sampler operates by advancing 1 '1 inch hollow push rods „ with the filter tip in a closed ' configuration to the base of the desired sampling interval {ince at the W ; desired sample depth, the push rods are retracted, exposing the encased usiy' re sampled filter screen and allowing groundwater ,r,� , Perched to infiltrate hydrostatically from the e GroundwMer formation into the inlet screen A small P � diameter bailer (approximately ' or s/ a . inch) is lowered through the push rods into the screen section for sample ' collection The number of downhole trips with the bailer and time necessary to complete the sample y ' collection at each depth interval is a function of sampling protocols, volume ; requirements, and the yield characteristics and storage capacity of Aquifer the formation Upon completion of ' sample collection, the push rods and sampler, with the exception of the PVC screen and steel drop off tip are retrieved to the ground surface, decontaminated and prepared for the next sampling event Figure GWS ' the groundwater samples collected, including the sampling date, � summary of gr mp depth and location identification, is presented in Table 1 and the corresponding CPT plot For a detailed reference on direct push groundwater sampling, refer to Zemo et al , 1992