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Health and Safety Plan 1319 & 1327 South Madison Street, Stockton,CA 432770 A E I Consultanlot ts accordance with manufacturer's instructions,and cannot not be used as a substitute for private utility locate contractors for evaluating exterior utilities,USTs,etc. 3.4.6 Direct Clearing Options Hand Clearing Hand clearance involves the actual removal of soil from the ground and is required along with geophysical survey at certain Sites Me- active gasoline stations], as presented on Table 1. At other sites, hand clearing or geophysical methods, in conjunction with evaluating other lines of evidence,as described above, is appropriate for clearing subsurface utilities. Prior to drilling, borings which are planned to a depth of five (5) feet or more must be evaluated for potential utilities as described above in Section 3.4.4, and directly cleared to a depth of at least five(5)feet. For borings planned to a depth of less than 5 feet,the borings should be cleared to their total depth. Borings should be directly cleared to a diameter which is as wide as the widest tool to be placed in the boring(e.g. borings to be drilled with 8-inch augers should be cleared to 8-inches in diameter). Hand augering involves the advancement of a hand-driven auger tool into the ground. The hand auger includes different bits which can be used depending on the type of soil such as sand or clay. Hand augering is typically used to create holes which are between 2 and 4 inches in diameter and these holes are then typically used to advance direct-push drilling equipment. The hand auger tool should be advanced into the subsurface by using even downward and twisting pressure. Hand augering works best in moderately consolidated soils without large gravels. Only a moderate amount of force should be used. Excessive force should not be used to advance a hand auger. Vacuum Clearing Vacuum clearance technology uses compressed air to break soil structure and allow for removal of the soil. Both dry and wet applications of these technologies can be performed. Both methods have inherent problems associated with compromising the borehole for collection of environmental samples.Typically,dry air knifing and vacuum extraction are preferred where soil samples must be collected in the top 5 feet of profile. Water jetting or wet vacuuming may also compromise future collection of groundwater samples, so is usually selected for boreholes advanced for remediation wells only. Vacuum clearance is recommended at all active gasoline service stations.