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Initial well redevelopment by swabbing and airlifting Is an extremely Important component of the well redevelopment process. G50SCIENCE anticipates that at least 60 hours of redevelopment by swabbing and airlifting will be necessary to properly remove and neutralize the chemicals Introduced in Task 63, and to redevelop tite filter pack and near well zone. GEOSCIENCE will provide part-time Inspection during the airlift development process and will closely monitor discharge water turbidity and sand content to track the development progress of the well. GEOSCIENCE will carefully follow sand concentrations within the discharge throughout the process and will provide direction to the Contractor should particular areas of the screen require additional work to reduce the sand to a mtnImum, a. Final Redevelopment by Pumping and Surging Final redevelopment by pumping and surging is a particularly Important part of the redevelopment process and requires close monitoring of water level and discharge date as well as sand content. GEOSCIENCE will monitor final development on a part-time basis. Tests for sand content and specific capacity will be performed frequently to pleasure the advancement of the development process and to ensure that, the well is fully developed before beginning the aquiferpumpingt%ts, GEOSCIENCE anticipates that a minimum of 40 hours will be necessary forthorough redevelopment, f. Step Drewdown and Constant Rate pumping Tests Once final redevelopment is datennined to be complete, pumping tests will be performed on the well to determine any changes to well and aquifer characteristics and to document sand readings over time from start of pumping. Recovery measurements should be collected for a minimum of four(4) hours following the constant rate pu nping test, The recommended aquifer pumping tests are as fctlows; * Step Drawdown Pumping Tests -to determine specific capacity and well sffiolency relationships. Typically three to four rates are selected for pumping, beginning at the lowest rate and working up to the highest. Constant Rate Pumping Test & Recovery Test -time drawdown and recovery measurements will be made to determine aquiferparameters such as transmisslvity and storativity, it is recommended that the constant rate test be Conducted for 24 hours with 4 hours of recovery measurements. GEOSCIENCE will provide fulidirne Inspection during the step drawdown test and part-time inspection during the 244hour oonstant rate and recovery test. g. Post -Redevelopment gownhoie Video Survey and Well Disinfection It Is recommended that a dual -scan downhole video survey be:eonducted within the well following redevelopment and testing to serve as a record of the post•radevdopment condition of the well casing and screen. GEOSCIENCE will provide full-time inspection duringthe video survey. The well should be disinfected as soon as redevelopment and aquifer pumping teats have been performed. A strong chlorine solution should be added to the well following removal of the lost dump to obtain a required minimum concentration of 200 milligrams perliter (mg1L) free chlorine concentration. GEOSCIENCE will provide full-time inspection of well disinfection to ensure that the proper concentrations of chlorine are used and that the chlorine is properly injected and dispersed within the well. 6, prepare sumenavy letter report At the conclusion of rehabilitation activities, GEOSCIENCE will prepare a letter report in iOQ% FINAL format that summarize, the details of the redevelopment and testing process. The report will, at a minimum, include the following: Pre�redevaiupment well condition, Chronology of activitlas, Description of methods used during well redevelopment, < Well redevelopment results and post -redevelopment well condition, Analysis and results of aquifer pumping tests, and • Other pertinent data, analytical results, recommendations and conclusions. Water and Sewer Pipeline Design TASK J. - PROJECT ADMINISTRATION Prior to the start of the project, we will have a kickoff meeting with City Staff and the project team to review the project objectives, schedule, the scope and approach. At this meeting, we will establish a point of contact for the project and request ail oveliable, information related to the project. In addition, the NV6 Project Manager will coordinate all aspects of the project and manage the schedule and costs to ensure the project's completion to the satisfaction of the City TASK 2 - RESEARCH EXISTING CONDITIONS c:9