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Initial well redevelopment by swabbing and airlifting.1s an extremely important component of the well redevelopment pr000ss, GEOSCIENCE anticipates that at least 6Q hours of redovajopment by swabbing and airlifting will be necessaryto plro'perly remove and neutralize the chemicals introduced in Task 6,$, and to redevelop the filter pack and near well zone, GEOSCIENCE will provide part-time inspection during the airlift development process and will elcacly,monitor discharge water turbidity and sand content to track the 0ovalopment progress of the well. GEOSCIENCII will carefully follow sand concentrations within the discharge throughout the process and will provide direction to "the Colitractor should particular areas of the soreen require additional work to reduce the sand'to a minimum„ a. Final Redevelopment by Pumping and Surging Final redevelopment bypumping and surging is a particularly important part of the redevelopment process and requires close monitoring of water level and discharge data as well as sand content. GEOSCIENCE will monitor final development on a part-time basis. Tests for sand content and speoific Capeelty will be performed frequently to mossure:the advancement of the development process and to ensure that the well is fully developed before beginning the aquifer pumping tests. GEOSCIENCE anticipates that a mininurn of 40 hours will be necessary for thorough redevelopment. f, Step Drawdown and Constant Rate Pumping Tests Once final redevelopment Is determined to be complete, pumping tests will be performed on the well to determine any changas 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 followingthe constant rate pumping test. The recommended aquifer pumping tests are as follows; • Step Drawdown Pumping Tests - to determine specific capacity and well efficlenoy 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 aquifer parameters 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 full-time impaction during the stop drawdown test and part-time inspection during the 24•hour constant rate end recovery test. g, Post -Redevelopment Downhole Video Survey and Well Disinfection it is recommended that a dual -scan downhole vldao survey be conducted within the well following redevelopment and testing to serve as a record of the post -redevelopment condition of the well Casing and screen. GEOSCMNQE will provide fuligime inspection duringthevideo survey, The well should be disinfected as soon as redevelopment and aquifer pumping tests have been performed. Astrdrig chlorine solution should be added to.the well following removal of the test pumpto obtain a requiredminimuim concentration of 200 inilllgrah s per 11tor.(mgTL) free chlorine oonpentration. GEOSCIENCEwill provide full-time inspection of well disinfection to ensure thatthe proper concentrations of chlorinsere used and that the chlorine Is properly injected and dispersed within the wail. 5, prepare rummary:letter report Atthe conelusion:ef rahabilitation;activities, GECSCIENCE. will prepare a letter report in 1A0% FINAL format that summarizes the details of the redevelopment and testing process, The report will, at a minimum, include the following: • Pre -redevelopment well condition, • Chronology of activities, • Description of methods used during well redevelopment, • Well redevelopment results and post -redevelopment well condition, • Analysis and results of aquifer pumpingtasts, and • Other pertinent data, analytical results, recommendations and conclusions. Water and Sewer Pipeline Design TASK 1 - PROJECT ADMINISTRATION Prior to the start of the project, we will have a kick-off 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 requestallavailable Information related to the project. In addition, the NV5 Project Manager will coordinate ell 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