HUNTER, CREIGHTON D. 1 - Laserfiche WebLink

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- t? )(11./:I,-f " A '1 ~A~.f. , Scope of work Leighton Consulting's proposed scope of work is summarized below. Task 1 - Pre-Field Activities Leighton Consulting will update the current site Health and Safety Plan and prepare a Supplemental Site lnvestigation Workplan for submittal to the City of Santa Ana Fire Department for their comment and approval. Leighton Consulting will mark-out the area of investigation and will contact Underground Service Alert (USA) two days prior to conducting field-work for their identification of utilities in the work area. Leighton Consulting will assist in obtaining the necessary encroachment permit to conduct a hand auger boring in the City sidewalk. Task 2 - Hand Auqer Borinqs Leighton Consulting proposes to advance two hand auger borings, HA-I and HA-2, in the suspected locations of the 5,000-gallon tank (HA-I) and the second 7,500-gallon tank (HA-2) as indicated on Figure 2. ]f present, the tank tops are anticipated to occur at a depth of 4 to 6 feet bgs. Task 3 - Direct Push and Hollow-stem Auqer Borinqs Leighton Consulting proposes to advance up to 6 borings, 13-] through 13-6, to depths of 40 to 115 feet bgs to further define the lateral and vertical e:-:tent of soil contamination. The proposed boring locations are shown in Figure 2. Boring B-1 will be drilled to a sufticient depth to sample groundwater or establish that 20 fcet of clean (non-impacted) soil is present above the first occurrence of groundwater. Borings B-2 through 8-6 will be advanced to 40 feet bgs. The objecti\'es of the borings arc discussed below: Boril1g B-1 Boring B-1 will be installed in the vicinity of the highest concentrations of gasoline impacted soil detected at the site, adjacent to the sidewalk and southwest of the discovered 7,500-gal1on UST. The boring will be advanced to a depth of up to ]] 5 feet bgs, utilizing a CME-95 UT hollo\\-stem auger drill fig. Soil samples ,,'ill be collected at five-foot intervals for " .-