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June 6,2007 NOA Project Number: E07082A The 25 foot deep borings on the parcels were used for the percolation tests.Within the borings, about an inch of"pea gravel"was placed in the bottom of the holes to stabilize the side wall from caving and prevent erosion while filling the boring. A 2-inch diameter PVC pipe with open ends and slots was placed in the hole. About 6-inches of pea gravel was placed in the annular space around the pipe. The hole was pre-soaked 24 hours prior to the test with 12 inches of water above the bottom of the hole. Presoaking of the percolation test holes occurred approximately 24 hours prior to the percolation tests. The percolation tests were conducted for the boxings on May 16 and June 1,2007 in accordance with the requirements of the EHD. A percolation test with a duration of four hours was performed for each hole. The final half-hour of each four-hour percolation test was observed by Ms.Amanda Boertien from the Environmental Health Department (EHD). 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 (attachment) 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 30 minutes for a period of four hours. 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 as being between 3.5 and 25 feet in depth;a satisfactory percolation rate for a deep test is 30 minutes per inch or less. Either a shallow or a deep percolation test must demonstrate a satisfactory rate within the proposed septic system disposal field to be suitable for a standard septic system. Details of the percolation tests are summarized in the following table. Table 2. Summary of Percolation Tests. Test No., Percolation Percolation Rate Test Comment Date Tested Test Depth(ft) (minutes/inch) Duration (see notes) Parcel 2 Deep 12.30 9.04 4-hr Satisfactory Percolation Rate 5-16-07 Parcel 3 Deep 11.20 22.72 4-hr Satisfactory Percolation Rate 5-16-07 Parcel 6 Deep 13.70 6.25 4-hr Satisfactory Percolation Rate 6-1-07 Note: A satisfactory percolation rate for a"shallow"test is less than or equal to 60 minutes per inch A satisfactory percolation rate for a"deep"test is less than or equal to 30 minutes per inch.