SU0006756 SSNL - Laserfiche WebLink

Home Browse Search

November 30, 2007. NOA Project Number: E07188A 6.3 Boring Preparation and Presaturation One shallow soil boring was advanced on the site with a hand auger on February 7, 2007. 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 hole occurred 24 hours before each percolation test. The depth of water used to pre-soak was 12 inches above the bottom of the boring. 6.4 Condition of Borings After.Presaturation After the 24-hour soak period, the presaturated hole was found to be intact and dry on February 8, 2007. 6.6 Percolation Test Procedure A percolation test was conducted for the boring on February 8, 2007 in accordance with the requirements of the EHD. A percolation test with a duration of four hours was performed. The last half hour of the 4-hour percolation test was observed by Ms. Amanda Bortien, 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 (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 four hours. 6.6 Percolation Test Forms and Results The completed percolation test form is included in the appendix of this report. A shallow percolation test is defined b the EHD as being between 36 and 42 inches in depth; a p Y g P 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 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 5. 8