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At 5-foot intervals the plug will be lifted from the hole and a Modified California Drive- Sampler will be driven through the inner pipe to obtain an undisturbed soil sample below the bit. Standard penetration test results (number of blows per 6-inch depth of penetration) will be recorded for each sample run. The soil sample will be described according to the procedures of the Unified Soil Classification System on a standard logging form. Based on boring logs kept during the drilling of the other wells at the holding ponds, it is expected that near-surface materials will consist of clays or silts to a depth of about 20 feet. Below that depth, it is expected that the upper portion of a thick sequence of silty sand to well-graded sand will be contacted. This geologic unit has been observed in each of the holding pond monitoring well boreholes, and in wells constructed at Holly Sugar Corporation to the west. The depth to groundwater is expected to be about 15 to 20 feet. HP-5 will be drilled about 15 feet below the water table. Construction The monitoring well will be screened in the sand unit since it is expected to provide a preferential pathway for groundwater flow because of its greater permeability. As with each of the other holding pond wells HP-5 will be constructed with 20 feet of slotted casing. This should allow screening across the water table and into the uppermost portion of the sand unit, with enough screening above the water table to allow for seasonal water level fluctuations. Monitoring well construction details are shown in Figure 4. Well completion details will be recorded in the field on a standard well construction form. Casing will consist of 4-inch- diameter Schedule 40 PVC. Sections of casing will be joined by threading, and the bottom of the casing will be capped with a threaded end cap. The lowest 20 feet of the casing will be open to the aquifer with 0.020 screen. The filter pack will be No. 3 Lonestar Monterey Sand or an equivalent, unless a finer grade sand is considered necessary in the field because of the presence of silty sand in the formation. The annular space above the filter pack will be sealed with 2 feet of bentonite pellets, while the annular space above the bentonite pellets to the ground surface will be sealed with cement grout. The top of the casing above the ground surface will be protected with a cylindrical steel casing set in a concrete pad. Cuttings from the borehole will be spread on the ground near the borehole. Any portion of the drill rig that may come into contact with the borehole, as well as flights of auger and well casing, will be steam-cleaned before use at the borehole. HP-5 will be constructed inside the auger drill stem, with the drill stem removed as the materials used to fill the annulus are emplaced. The casing will be suspended in the auger about 1 foot above the bottom of the borehole. Filter pack will then be emplaced in approximately 2-foot lifts to prevent bridging. No water will be used, unless approved by the site geologist to prevent saturated silty sands from flowing up the annulus. The depth to the top of the filter pack will be frequently tagged using a weighted measuring tape to monitor bridging and settling. Filter pack will be added until it is about 3 feet above the top of the slotted screen. SAC/SAC36357/041.WPS 6 8/94