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Work Plan and Health and Safety Plan BSK Project No. G1910411L North Manteca Trunk Sewer Test Well June 17, 2019 Manteca, California Page 2 SCOPE OF SERVICES I Task 1— Field Coordination and Permitting This task will include locating the test well borehole in the field, utility clearance, and permitting. BSK will visit the project site to locate and mark the test well borehole location,and contact USA North 811 a minimum of 72 hours prior to our subsurface exploration for utility clearance. A private utility locator will also be scheduled to clear the test well location. As required by local ordinance, a drilling/well installation permit will be obtained from San Joaquin County (County) prior to our field investigation. An encroachment permit will not be required since the test well will be located within City of Manteca Right-of-Way. Task 2 —Subsurface Investigation The subsurface investigation will consist of the pumping of groundwater from the test well at different rates and measurement of the water level at intervals of time during pumping, and after pumping has ceased, to characterize the capacity of water-bearing sediments to yield water over time (transmissivity), and the amount of drawdown within the well at different pumping rates. Th pur os of this investigation is to better understand the level of effort require to dewater open excavations during installation of sanitary sewer piping and facilities during construction of the North Manteca Trunk Sewer. BSK will retain a California C-57 licensed water well driller to install the test well. We propose to install at 4-inch internal diameter (ID) test well to a depth of 35 feet, with 0.020-inch width screen slotting from 15 bgs to 35 feet bgs and solid casing from 15 feet bgs to the ground surface; an additional 2 feet of well casing will comprise a riser above the ground surface to help prevent material from entering the well during testing.The annular space between the borehole walls and the well casing will be filled with clean, #212 grade sand from 35 feet bgs to two feet above the screen interval, at 13 feet bgs. A bentonite clay seal will be installed from 11 feet to 13 feet bgs, overlain by a neat-cement grout to the surface. The surface seal will be allowed to cure for 72 hours before the well is used. Soil cuttings generated from the boring will be disposed at an unimproved location adjacent to the borehole. The well boring observations will be recorded on a detailed boring log at 5-foot intervals from the ground surface to a depth 35 feet bgs to observe and classify subsurface sediments using the former American Society for Testing and Materials Method (ASTM), now "ASTM International', Standard D2488. Our evaluation of groundwater transmissivity within the range of the dewatering well will consist of a step-drawdown test conducted over a period of 12 to 18 hours, depending upon the stabilization of Bzl<