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<br />Page 2 <br /> <br />Green Environment inc, <br />Subsurface Investigation Proposal <br />City Parking Lot Between 2053 and 2065 Broadway Avenue, Redwood City, CA <br /> <br />Task 2. Drilling and Soil Sampling <br /> <br />. <br /> <br />Drill five (5) GeoprobeTM borings, designated GEI-Bl to GEI-B5, and collect soil <br />samples for laboratory analyses. The shallow borings will be advanced to a maximum <br />twelve (12) feet depth. Up to two (2) soil samples per boring will be collected for <br />laboratory analyses. <br /> <br />. Install temporary well casing in each boring to facilitate groundwater sampling. <br />Provide a temporary seal around the top of the encased borehole. Place temporary <br />cover and protection around each temporary well casing. <br /> <br />. <br /> <br />Place soil cuttings in a DOT 55-gallon drum. Seal, label and place the drum in the <br />City parking lot for temporary storage. <br /> <br />Task 3. Shallow Groundwater Sampling <br /> <br />. <br /> <br />Collect a grab sample of groundwater from each of the encased boreholes once <br />sufficient volume has accumulated for sampling purposes. Allow up to three (3) days <br />from well casing installation for groundwater to accumulate before sampling. <br /> <br />. <br /> <br />Measure depth-to-water in the temporary well casings using an electronic water level <br />sounder, express measurements relative to a fixed, labeled point on the top surface of <br />the pavement. Measure depth-to-water daily in the interim between drilling and <br />groundwater sampling. <br /> <br />. <br /> <br />Following groundwater sampling, remove the well casings and tremie grout the <br />boreholes with neat cement upward from the bottom of each boring and manage <br />displaced groundwater as a waste. <br /> <br />Task 4. Deeper Groundwater Sampling <br /> <br />. <br /> <br />Using dual-casing GeoprobeTM equipment, drill three (3) borings into the deeper <br />water-bearing zone to a maximum 35 feet depth in the vicinity of Borings GEI-Bl, <br />GEI-3 and GEI-4. Up to two (2) additional soil samples per boring will be collected <br />for laboratory analyses. <br /> <br />. <br /> <br />Install temporary well casing in each boring to facilitate groundwater sampling, and <br />collect a grab sample of groundwater from each encased borehole. <br />