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wells and can be exported for the report and the MDH
<br />well record
<br />o SEH will review well construction as -built construction
<br />against the specification, including casing depths,
<br />grout volumes, and open hole interval, for the MDH well
<br />construction record
<br />V Deliverables: Boring log and well construction diagram
<br />for each test hole and test well, with photo log.
<br />Assumptions: One 10-hour field day per test hole and test
<br />well, four test wells total, as stated in the RFP.
<br />Our certified geologists log cuttings and core during
<br />drilling, identifying geology such as the bagged
<br />Rotosconic drilling samples pictured here, consisting
<br />of clay, sand, weathered bedrock, and bedrock.
<br />Bedrock core is documented by depth, as depicted
<br />here with this 40 to 50 feet interval log.
<br />'4
<br />TASK ® AQUIFER PUMPING TEST
<br />WORK PLAN AND IMPLEMENTATION
<br />SEH will prepare an aquifer pumping test work plan
<br />and run a 72-hour constant -rate test on each test well.
<br />The work plan will follow MnDNR and MDH aquifer
<br />test guidance and will be submitted with the Task 7
<br />assessment. SEH will:
<br />o Prepare the work plan with the pumping rate, duration,
<br />observation well network, water level measurement
<br />schedule, discharge routing, and data quality checks for
<br />each test
<br />o Install up to two pressure transducer data loggers for
<br />each test per the RFP, one in the pumping well and one
<br />in an observation well, and program them for operation
<br />for the full 10-day monitoring period
<br />o Collect 72 hours of background water level data
<br />before pumping to define natural trends and
<br />barometric effects
<br />o Direct the drilling contractor during the 72-hour
<br />pumping period, including pump start, rate control,
<br />flow measurement, and manual water level checks
<br />(SEH staff will be on site at the start of the background
<br />period, the start of pumping, and the start of recovery)
<br />o Monitor recovery after pumping stops until water levels
<br />return to near static
<br />o Collect water quality samples at the end of each
<br />pumping test for general chemistry, iron, manganese,
<br />hardness, nitrate, and other parameters agreed with
<br />the City, with field measurement of pH, temperature,
<br />specific conductance, dissolved oxygen, and ORP
<br />(Samples will be analyzed by a certified laboratory)
<br />o Download and check data logger records after each test
<br />V Deliverables: Aquifer pumping test work plan and
<br />field data for each test, including logger files, manual
<br />measurements, and laboratory results.
<br />TASK ® DATA ANALYSIS AND REPORT
<br />SEH will analyze each pumping test and recommend a
<br />public water supply well design for Wells #9 and #10.
<br />SEH will:
<br />o Correct water level data for barometric and background
<br />trends and analyze each test in AQTESOLV with the
<br />analytical solution that fits the aquifer conditions
<br />(such as Theis, Cooper -Jacob, or Hantush-Jacob
<br />leaky aquifer)
<br />o Calculate transmissivity, hydraulic conductivity,
<br />storativity, specific capacity, and well efficiency,
<br />and compare the results to the 2021 values and to
<br />published well potential criteria
<br />o Update the interference and safe -yield evaluation from
<br />Tasks 3 and 4 with the measured aquifer parameters
<br />o Compare water quality between sites and against MDH
<br />treatment requirements
<br />o Recommend a production well design for each selected
<br />site, including depth, casing diameters and depths,
<br />open hole interval, expected capacity, and pump setting
<br />SHORT ELLIOTT HENDRICKSON INC.
<br />WELL SITING ASSESSMENT FOR MUNICIPAL WELLS #9 AND #10
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