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MonitorinL7 Well Installation Procedures - The monitoring well consists of 4 -inch diameter Schedule 40 PVC casing set in an 10 -inch diameter boring The boring was drilled under the direction of an engineer or geologist from our firm. A ' detailed boring log was kept at all times noting 1) material types encountered with depth (Unified Soils Classification System), and 2) moisture conditions The boring was drilled using a CME -75 ' drill rig equipped with 10 -inch diameter continuous flight hollow stem augers The monitoring wells consist of a bottom plug followed by 20 feet of Schedule 40 PVC screen with factory machined horizontal slots (0 020 -inches), then blank casing to the surface Each section of casing is joined together using factory -made threaded connections, thereby eliminating the necessity for any glues or solvents The well packing material consists of pre -washed medium grained sand and extends ' a minimum of 2 feet above the slotted casing Bentonite tablets were used to seal the well casing A 6 -sack sand/cement slurry was used to backfill the remainder of the boring A locking cap was ' set on top of the well head which is set slightly below grade A flush mounted water tight box was used to protect the well head A well log for each monitoring well was submitted on the ' appropriate form to the California Department of Water Resources Soil cuttings generated by the drilling operations were stockpiled at the project site Water produced during well development and sampling operations was stored in 55 gallon drums at the site Ground -Witter Samyling Methods A ground -water sample was collected from each monitoring well Prior to sampling the well, approximately five well volumes were removed in order to bring fresh formation water into the well The ground -water sample was collected using a pre -cleaned teflon bailer. The teflon bailer was cleaned in a trisodium phosphate (TSP) solution, rinsed with clean water, rinsed with methanol, and finally rinsed with deionized water and allowed to air dry The ground -water sample was placed in the appropriate glass containers with teflon -lined lids Each sample was labelled and immediately placed in an ice chest and cooled to 4°C using blue ice