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3 —Construction Activities Dust or Noise Mitigation Vehicles driven on unpaved roads will travel at speeds that minimize dust. If reducing traveling speeds on unpaved roads is not enough to control dust, then the roads used by work crews will be sufficiently sprayed with water at the beginning of each day. Wetting will occur more frequently during the day or night as needed to prevent the occurrence of dust nuisance. Drilling and Well Construction Work crews will mobilize to the work site with all equipment necessary to construct the project improvements. On the first and every day of field work, a minimum 10 -minute safety meeting will be conducted by work crews to review, discuss, and sign a daily Job Hazard Analysis sheet. The following details outline the general project construction: The work site will be set-up for efficient execution of work tasks. Direct mud -rotary drilling, drill fluid conditioning, and drill cuttings containment will be performed to: a. Drill a 12.25 -inch -diameter pilot hole to a total depth of approximately 1,650 feet below the ground surface. b. Conduct geophysical logging to the total borehole depth including: natural gamma ray; spontaneous potential; short -normal, long -normal, and lateral (point) electrical resistivity, and; caliper logs. c. Construct a dual -completion monitoring well in the pilot hole for the two deepest target zones. d. Step -over at least 10 feet and drill a second boring to construct a quadruple -completion monitoring well (e.g., four well casings in a single borehole) for the four additional targeted zones. All of the following tasks will be completed under the direction of a Professional Geologist: a. Supervision of the drilling, well construction, and well development operations. b. Examination of drill cuttings during drilling and creation of a lithologic log of the boring. c. Review of the lithologic and geophysical logs alongside each other and selection of the final well screen depth intervals according to hydrostratigraphic interpretation and concurrence with the GSA. d. Creation of a field as -built well construction diagram. 4. In general, well construction will involve: a. Final reamed borehole diameters of: i. 12.25 inches for the deep borehole ii. 12.25 inches below 400 feet and 14 -inches above 400 feet for the shallow borehole b. Based on preliminary design by the GSA with DWR input, well specifications are targeted to be: i. 2.5 -inch diameter, Schedule 80 PVC blank casing. ii. 2.5 -inch diameter, Schedule 80 PVC, 0.020 -inch -wide, mill -slotted well screens. iii. Each water bearing zone is expected to have a screen interval approximately 40 -feet - long. c. A surface well seal of appropriate mixture and depth to meet well permit requirements will be set. d. Each well will be finished at the surface with a steel pipe with locking cover and concrete apron. Security fencing will also be installed to protect the well from cattle. Work crews will demobilize all equipment used to construct the project improvements, clean up all work-related waste and unused materials, and return work areas to their original condition. Well Development Well development will occur no sooner than 32 hours after the well surface seal has been completed. Well development will be accomplished by a combination of swabbing, surging, bailing to remove sediment, and purging with a submersible or air lift pump. Well development will be performed until there is good hydraulic connection between the formation and the well screen, or for a maximum of 4 hours if turbidity reduction is not easily achieved. Termination of well development activities is at the discretion of the site Professional Geologist.