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initial well redevelopment by swabbing end airldting Is an <br />ommely Important component of the well redevelopment <br />process. GEOSCIENM anticipates that at least 60 hours <br />of redevelopment by $Webbing and oirliftIng will be <br />necessaryto property remove and neutralize thachernicals <br />Introduced In Task 6.,9, and to redevelop the filter peak <br />and near well zone, GEOSCIENCE Will provide part-time <br />Inspection during the airlift development process and <br />will closely moriltor discharge water turbidity and sand <br />coKent to track the development progress of the wall. <br />Qi�OSOIENcE will carefully,foilow sand concentrations <br />wlthinthe discharge throughOut the process and will <br />provide direction to the Contiectorshould partloular areas <br />of the screen require additional work to reduce the sand to <br />0 minimum, <br />e. Final Redevelopment by Pumping and Surging <br />Final redev.elopniefvtbypumpingend�surging6-a <br />particularly Important Part of th@ redevelopment Process <br />and requires close.monitDring of water level and discharge <br />data as well assand content. GEOSCIENCE Will monitor <br />final development on a part-time basis, Tests for sand <br />content and speciflo capacity will be performed. frequently <br />tDoeasure the advancement of the development process <br />and to ensure thatthe well isfully developed before <br />beginning the aquifer pumping tests. GEOSCIENCE <br />anflelpai,,;� that a minimum of 40 hours will. be necessary <br />forthorough redevelopment <br />t. Step Drawdowh and Constant Rate Pumping Tests <br />once final redevelopment Is determined to be complete, <br />pumping tests will be performed on the well to determine <br />any changes to well and aquifer characteristics and to <br />document sand readings over time from start of pumping, <br />Recovery measurements should be Collected for a <br />minimum of four (4) hours followingthe constant rate <br />pumpingtest. The recommended aquifer Pumping tests <br />are as follows: <br />• Stop Drawdown Pumpinglasts; -to determine <br />specific capacity and well effiolenoy relationships, <br />Typic - ally three to four rates are selected for pumping, <br />beginning at the lowest rate and working up to the <br />highest <br />• Constant Rate Pumping Test & Recovery Test - time <br />drewdown and recovery measurements will be <br />made to determine aquifer parameters Such as <br />transimissivity and storatIvIty. it is recommended that <br />the constant rate test be conducted for 24 houm with <br />4 hours of recovery measurements, <br />(�VOMENCE will provide full-time inspection during the <br />step dmwdo*n test and part-timer inspection during the <br />24-hour Constant rate and recovery test. <br />post -Redevelopment Downhols fteu Survey and Well <br />Disinfection <br />It is recommended that a dual -$can downhole video survey <br />be conducted within the Wei I following redevelopment and <br />testing to sam as a record of the Post-rtidemlVment <br />condition of the well casing and screen. GEOSCIENGE will <br />provide full -lime inspection during the video survey. <br />The well should be disinfected 0"00h as redevelopment <br />and.aqpI* pumping tests lime been performed. A strong <br />chlorine solution should be added to the well following <br />removal of the 1e* Pump to obtain a required minimum <br />concentration of 200 "lligraft per fiterinig/L) free <br />chlorine concentration. GEORGIENCE will provide fult-time <br />inspection of well disinfection to ensure that the proper <br />tomentratioris of, Chlorine are used ard that the chlorine <br />is proparlyinjeoted and dispersed within the well. <br />S. Prepare summary letter report <br />At the conclusion of rehatillitation.actlyides, GEOSCIIENCE <br />will prepare a letter report in :100% FINAL foffirW that <br />summarizes the details of the redevelopment and testing <br />process. The report will, at a affnimum. include the <br />following: <br />• Pre-railevoloPment wall condition, <br />• Ohronology of activities, <br />• Description of methods used during well <br />redevelopment, <br />* Well redevelopment results and post�redeVebpnrient <br />wall condition, <br />o Analysis and results of aquifer pumping tests, end <br />- Other pertment data, analytical results, <br />recommendations and conclusions. <br />Water and Sewer Pipeline Design <br />TASK I - PROJECT ADMINISTRATION <br />prior to the start of the project, we will have a kick-off <br />meeting with City Staff and the Project team to review the <br />project oWqoUves, schedule, the scope and approach. <br />At this meeting, We will establish a point of contact for <br />the project and request all available Information related <br />to the project. In addition, the NVS Project.Manager will <br />coordinate all aspects of the project and manage the <br />schedule and Costs to ensure the projears completion to <br />the satisfaction of the City. <br />TASK 2 - RESEARCH EXISTING CONDITIONS <br />I <br />H pa <br />. <br />51 <br />25E-512 <br />