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GeosyntecD <br /> consultants <br /> raised and allowed to drain back into the hole in order to induce flow out through the well <br /> screen. <br /> A surge block may be used to flush the filter pack of fine sediment in instances where field <br /> personnel expect that development may be improved by surging. Surging will be <br /> conducted slowly to reduce disruption to the filter pack and screen. Following surging, the <br /> well will be pumped or bailed again to remove sediment drawn in by the surging process <br /> until suspended sediment is reduced to acceptable levels (see below). Water shall not be <br /> added to the well to aid in development. <br /> A well is considered fully developed when all the following criteria are met: <br /> • the well water is clear to the unaided eye (based on observations of water clarity <br /> through a clear glass jar) and turbidity readings have stabilized to +/- 10% over <br /> three consecutive readings; <br /> • the sediment thickness remaining in the well is less than one percent of the screen <br /> length; and <br /> • the total volume of water removed from the well equals five times the standing <br /> water volume in the well (including the well screen and casing plus saturated <br /> annulus,assuming 30 percent porosity)plus the volume of drilling fluid lost. <br /> The cap and all internal components of the well casing above the water table shall be <br /> rinsed with deionized water to remove all traces of soil, sediment, and cuttings. This <br /> washing shall be conducted before and/or during development. <br /> Non-dedicated pumps shall be decontaminated prior to use in the next well and dedicated <br /> tubing and/or bailers shall be used during subsequent sample collection from the well. <br /> 4.1.2.3 Well Sampling <br /> Once the wells have been installed and properly developed, they will be added to the <br /> next groundwater sampling event schedule. Groundwater samples intended for VOC <br /> analysis will be collected from the wells using passive diffusion bag (PDB) samplers in <br /> accordance with SOP 5.0 (Appendix B). Any other groundwater sample intended for <br /> non-VOC analysis, if desired, will be collected from the wells using the low-flow <br /> purging and sampling technique in accordance with SOP 6.0 (Appendix B). All <br /> groundwater samples will be stored in an iced cooler, packaged under COC protocol, <br /> and shipped to a California-certified analytical laboratory as described below in Section <br /> Pre-Design Investigation Work Plan 20 18.05.12 <br />