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<br /> off the splitspoon sampler. Top of the water table was again encountered at twenty (20) f
<br /> feet below ground- evel and the boring was advanced ahead to a total depth of thirty (30)
<br /> feet. E
<br /> On March 28, 1994, both borings were converted to monitoring wells using slotted and
<br /> blank, screw type, internal flush, 4" OD PVC casing, the wells were gravel packed with
<br /> !� #2/12 Monterey sand, and a bentonite seal was placed on top.
<br /> f! All of the brass tubes containing the soil samples from these two borings had their ends
<br /> covered with aluminum foil, then plastic caps were placed over the ends, securely sealed
<br /> € with duct tape, labeled for identification, and stored on ice in an ice chest for transportation
<br /> to FGL Environmental, a state certified laboratory. The soil samples were delivered by the
<br /> chain of custody, EXHIBIT P, for analysis of BTEX (EPA Method 8020), TPH-Gas (EPA
<br /> Method 8015 as), and Lead (EPA Method 7420).
<br /> On March 1, 993 Spectrum Drilling returned to the site for the boring of monitor well
<br /> MW3 which was ocated in the sidewalk adjacent to the property,Y� EXHIBIT O and Plate
<br /> VIIIa. An encroachment permit, EXHIBIT N, was granted by the City of Stockton,
<br /> i Department of Public Works, for the placing of monitor well MW3. Again it was necessary
<br /> to remove a concrete square six (6) inches thick cut with a power saw before starting the j
<br /> boring. Soil samples were collected in this boring at depths of 101/2-11 (MW3-1), 15'h- j
<br /> Ij 16 (MW3-2), and 201/2-21 (MW3-3). As in the other two borings, the top the water table
<br /> was found at twenty (20) feet below ground level and the boring was carried ahead to a
<br /> a depth of thirty (30) feet, PLATE IX. No apparent sign or odor of petroleum (gasoline)
<br /> contamination was detected in this boring. The soil samples were packaged, stored,
<br /> i transported, and delivered in the same manner as stated above to FGL Environmental .i
<br /> i Laboratory and for the same analysis. The boring was cased with PVC casing, sealed with
<br /> i bentonite, and all three monitoring wells were then grouted to the top with cement.
<br /> i
<br /> All three (3) borings were done with pre-cleaned auger flights to prevent cross
<br /> contamination and the spoils from each boring were placed in steel drums, secured with
<br /> lids, and identified as to which boring, and stored on location. Water used on location for
<br /> cleaning equipment was also placed in a steel drum, secured with a lid, and stored on site.
<br /> The laboratory results from these borings will determine the final disposition of these €
<br /> Ip
<br /> containers.
<br /> €€ MONITOR WELLS:
<br /> Each boring was converted into a groundwater monitoring well by installing clean 4" OD,
<br /> screw-type, internal flush, blank and slotted, schedule 40 PVC casing capped on the bottom,
<br /> gravel packed, sealed and grouted as shown on the enclosed schematics, EXHIBIT O. The
<br /> t i casing was set approximately 6" off bottom before it was gravel packed, sealed, and grouted.
<br /> it Each well was equipped with a preformed surface vault, thoroughly cemented in place, and
<br /> a suitable heavy duty locking traffic cover. The casing extended far enough up into the
<br /> vault to allow placement of an expandable cap and lock assembly. The top of each casing
<br /> i� measurementsand the well covers were clearl
<br /> was notched on the north side to facilitate y �
<br /> identified for future reference.
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<br /> Iii E
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