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� October 31, 2005 NOA Project Number: E05137A 0 A 1.5-inch diameter PVC pipe with perforations on the bottom was used to measure the drop of water 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. Presaturation of the percolation test holes occurred on October 13,20, and 27, 2005. The depth of water used to � pre-soak was 12 inches above the bottom of the borings.� 6.4 Condition of Borings After Presaturation After the 24-hour soak period,the presaturated shallow holes were found to be intact and dry on October 14. After the 24-hour soak period, the presaturated deep hole on Parcel two was found to be intact and dry on October 14, the deep hole on Parcel one was found with 4 inches of water remaining at the bottom. Parcel P-2 deep was found to be dry and intact on October 21, 2005. j Parcel 1 deep test was found to be dry and intact on October 28, 2005. 6.5 Percolation Test Procedure Percolation tests were conducted for the borings on October 14,21 and 28, 2005 in accordance with the requirements of the EHD. A percolation test with a duration of either one hour or four hours was performed for each hole. The Ms. Lisa Medina, Senior Registered Environmental Health F[ Inspector,EHD observed the percolation tests in accordance with EHD requirements. Measurement of the water level during the percolation test was from a fixed reference point on the 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 every either every 10 minutes for a 1-hour percolation test or every 30 minutes for a 4-hour percolation test. t 6.6 Percolation Test Forms and Results d_ f The completed percolation test form is included in the appendix of this report. F1A 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 as being between 3.5 and 25 feet in depth;a satisfactory percolation _. rate for a deep test is 30 mire/in or less. 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. 8