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Each borehole will be continuously sampled and visually classified and described by a <br />qualified geologist or engineer. Selected samples will be retained for geotechnical analysis, <br />consisting of grain size determinations by the wet-sieve method at a maximum of 4 intervals <br />per well. Cores will be photographed for additional documentation. <br />The Consultant's on-site representative will be present for all drilling activities and maintain a <br />log of all significant well construction and testing activities. <br />All wells will be drilled to bedrock and completed with up to a 20-foot screen interval <br />selected in the field by the Consultant, based on the lithologies encountered. <br />Wells will be constructed of 4-inch PVC with amill-slotted screen up to 20-feet long. Well <br />completion will be in accordance with State regulations. <br />The well will be developed by surging and pumping and the produced water discharged to the <br />surface. <br />A surveyor licensed in the State of Colorado will be selected and sub-contracted to provide <br />vertical and horizontal coordinates using precision differential GPS methods. <br />A single-borehole aquifer performance test will be conducted after each well is completed and <br />developed. Large capacity wells within 2000 feet will be checked to verify that they are not <br />pumping. Pumping will be conducted at a sustainable constant rate for a period not greater <br />than 8 hours. Water from testing will be discharged to overland flow or nearby surface water <br />bodies without treatment or chemical testing. Permits for discharge of water from the <br />performance testing will be obtained from the Colorado Department of Health and <br />Environment prior to starting the performance tests. Water level data will be recorded during <br />the pumping and recovery phases using a pressure transducer and data logger. Aquifer <br />performance testing results will be reduced and interpreted using industry standard graphical <br />analysis techniques based on the Cooper-Jacob method of analysis. <br />An in-well pressure transducer and data logger will be installed in each of the 15 wells and <br />operated fora 10-month period outside of the irrigation season. <br />The data will be recorded at an hourly interval and normalized to elevation for reporting. After <br />initial installation and confirmation of operation over atwo-week start-up period, data will be <br />retrieved on asemi-annual basis. <br />This data will be used to analyze water levels as part of Task 44 <br />Deliverables: <br />Task 35.2 Phase 1 Denver Basin Region Alluvial Well Construction and Testing Report <br />A single Report will be prepared for the alluvial wells constructed in the Denver Basin <br />Region. <br />This memorandum will include the following: <br />SPDSS Groundwater SOW, Phase 1 Page 13 <br />