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L .Oi LDecember 1,2004 /NOA Project Number: E04117A Ly 6.3 Boring Preparation and Presaturation L A total of two shallow and two deep soil borings were advanced on the Site with a truck-mounted B53 augur rig on November 10, 2004. A 1.5-inch diameter PVC pipe with perforations on the bottom was used to measure the drop of Lwater in the percolation test boring. Approximately 2 inches of"pea gravel' were placed in the bottom of the open soil boring, then the PVC pipe was installed on top of the gravel. Several feet of"pea gravel' were backfilled in the annular space. LPresaturation of the percolation test holes occurred on November 15,2004. The depth of water used to pre-soak was 12 inches above the bottom of the boring. L /6.4 Condition of Borings After Presaturation LAfter the 24-hour soak period, the presaturated holes were found to be intact on November 16, 2004. The P-1 deep,parcel 1, hole was still wet and the shallow hole was dry. The P-2,parcel 2, deep and shallow holes were both dry on November 16,2004. 6.5 Percolation Test Procedure L Percolation tests were conducted for the borings on November 16,2004 in accordance with the requirements of the EHD. A percolation test with a duration of one hour was performed for each hole. The test in its entirety was observed by Ms. Lisa Medina, Senior Registered Environmental LHealth Inspector, EHD. Measurement of the water level during the percolation test was from a fixed reference point on the L PVC casing using an electric well sounder with an depth accuracy of 1/100th foot. All tabulated values on the field data sheet (appendix) are in decimal feet. After water drop was observed, the holes were checked for refill. The refill level was approximately 0.5 ft (6 inches) of water above the bottom level of the percolation test hole. The readings were taken approximately every 10 minutes for a period of one hour. L6.6 Percolation Test Forms and Results The completed percolation test forms are included in the appendix of this report. L A shallow percolation test is defined by the EHD as being between 36 and 42 inches in depth;a satisfactory percolation rate for a shallow test is less than or equal to 60 minutes per inch drop. A L deep percolation test is defined as being between 3.5 and 25 feet in depth; a satisfactory percolation rate for a deep test is 30 min/in or less. One percolation test must demonstrate a satisfactory percolation rate within the proposed septic system disposal field of each parcel. Details of the Lpercolation tests are summarized in Table 6. 8 I` o-44L