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clearly inappropriate. Pumps used for well development shall be periodically raised and allowed to drain back into the hole in order to induce flow out through the well screen. A surge block may be used to flush the filter pack of fine sediment in instances where field personnel expect that development may be improved by surging. Surging will be conducted slowly to reduce disruption to the filter pack and screen. Following surging, the well will be pumped or bailed again to remove sediment drawn in by the surging process until suspended sediment is reduced to acceptable levels (see below). Water shall not be added to the well to aid in development. A well is considered fully developed when all the following criteria are met: • the well water is clear to the unaided eye (based on observations of water clarity through a clear glass jar) and turbidity readings have stabilized to+/- 10%over three consecutive readings; • the sediment thickness remaining in the well is less than one percent of the screen length; and • the total volume of water removed from the well equals five times the standing water volume in the well (including the well screen and casing plus saturated annulus, assuming 30 percent porosity)plus the volume of drilling fluid lost. The cap and all internal components of the well casing above the water table shall be rinsed with deionized water to remove all traces of soil, sediment, and cuttings. This washing shall be conducted before and/or during development. Non-dedicated pumps shall be decontaminated prior to use in the next well and dedicated tubing and/or bailers shall be used during subsequent sample collection from the well. Well Sampling Once the wells have been installed and properly developed, they will be added to the next groundwater sampling event schedule. Groundwater samples intended for VOC analysis will be collected from the wells using passive diffusion bag (PDB) samplers in accordance with SOP 5.0 (Appendix B) of the Work Plan. Any other groundwater sample intended for non-VOC analysis, if desired, will be collected from the wells using the low-flow purging and sampling technique in accordance with SOP 6.0 (Appendix B) of the Work Plan. All groundwater samples will be stored in an iced cooler, packaged under COC protocol, and shipped to a California-certified analytical laboratory as described in Section 4.2.5 and in the QAPP(Appendix A) of the Work Plan. Sample containers will be labeled with sample identification number, date, time, requested analyses, preservation method, and sampler's initials. Groundwater samples from the wells will be analyzed for VOCs using USEPA Method 8260B. Well Survey Access Agre ml 2010 8