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A-3.2 Monitoring Well Development and Sampling <br /> The wells are developed to reduce the effects of drilling on the formation and to increase <br /> the effective hydraulic radius of the well. <br /> Monitoring wells are generally developed 24 to 48 hours after installation to allow the <br /> grout to set. Each well is first sampled with a clear acrylic bailer to visually inspect for <br /> hydrocarbon layer or sheen. If no product layer or sheen is observed on the water, the well <br /> is developed by surging, pumping, or bailing. Surging along the screened interval of the <br /> well is performed to draw the sediment from the formation into the filter pack and the well <br /> and to set the sand pack. The sediment laden water is purged from the well at a rate of <br /> between 0.75 to 10 gallons per minute (gpm) depending on recharge rate and casing size. <br /> Development continues until the discharge runs relatively clear of fines. Approximately 5 <br /> to 10 well volumes are generally removed from each monitoring well. Discharge water is <br /> stored in 55-gallon drums and left onsite for later discharge or disposal by the client, <br /> depending on laboratory results. <br /> After the wells are developed, the aquifer is allowed to equilibrate for at least 24 to 48 <br /> hours. The wells can then be ,purged and sampled. Purging and sampling may be <br /> accomplished with Teflon bladder pumps and/or bailers. During the purging of the wells, <br /> field parameters (pH, conductivity, and temperature) are monitored. Samples are <br /> collected after the field parameters have stabilized (normally requiring the removal of <br /> three to five well volumes). Water sampling containers are supplied and prepared by the <br /> laboratory. These sample containers are immediately sealed after sample collection and <br /> placed in an iced cooler. At the end of the day, the water samples are delivered under <br /> chain-of-custody to an analytical laboratory certified by the state for the planned chemical <br /> analysis. <br /> A-3.3 Sample Handling <br /> After labeling, the sample is immediately stored in an iced cooler for transport to the <br /> analytical laboratory. The label includes Kleinfelder's name, job number, the date and <br /> time the sample was collected, the employee number of the individual who performed the <br /> sampling, and a unique five-digit sample identification number. A custody seal is also <br /> placed on the sample in such a way that any attempt to tamper with the sample is easily <br />