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L LJune 6, 2006 NOA Project Number: E06019B 6.3 Boring Preparation and Presaturation L One shallow and one deep soil boring were advanced on each parcel on the Site with a truck mounted deep rock augur rig on May 17, 2006. 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. "Pea gravel" was then used to backfill in the annular space. i. Presaturation of the percolation test holes occurred approximately 24 hours before the percolation tests.The depth of water used to pre-soak was 12 inches above the bottom of the borings. L 6.4 Condition of Borings After Presaturation LAfter the 24-hour soak period, the majority of the presaturated holes were found to be intact and dry on the day of testing. L 6.5 Percolation Test Procedure The percolation tests were conducted for the borings on May 18, 2006 in accordance with the requirements of the EHD. A percolation test with a duration of four hours was performed for each hole. The last half an hour of the tests was observed by Mr. Michael Escotto,Registered Environmental Health Specialist, EHD. LMeasurement of the water level during the percolation test was from a fixed reference point on the 7� PVC casing using an electric well sounder with an depth accuracy of 1/100th foot Alltabulated 'L 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 every 30 minutes for a period of Lfour hours. 6.6 Percolation Test Forms and Results The completed percolation test forms are included in the appendix of this report 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 deep percolation test is defined by the EHD as being between 36 inches and 25 feet in depth;a satisfactory percolation rate for a deep test is less than or equal to 30 minutes per inch drop. One percolation test must demonstrate a satisfactory percolation rate within the proposed septic system disposal field of each parcel to utilize a standard septic system. Details of the percolation tests are summarized in Table 6. L 8 L L