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October 4,2001 . Job Number:LGOO-287 } 4 Page l Eighteen(18),soil borings were drilled on the property between August 2000,and. September 2001. Due to the extensive clayey soils which lack clean permeable sand, several different areas were evaluated to locate suitable soils for a septic system. The soils appeared to be generally homogeneous throughout the site. The soils consist of brown fine-to medium sandy clay with,occasional thin clayey silt zones often found between 4 to 8 feet in depth. All the clayey soils-were difficult to drill, very'stiff, and slightly to moderately cemented. The most permeable zone was on the site was.found to be in the northwest corner of the ro ert . A 25.foot deep percolation test used to evaluate the north cast corner for an engineered Septic stem contained'agT eater amount of sand in the auger cuttings and indicated a high . Y percolation rate during percolation test utilizing an alternate test method (Plate 1). Though no - sandy zones,were directly`identified, there may be one or several permeable layers in the' northeast cornet of the property_ All the test holes were drilled by Neil O. Anderson& Associates,:Inc. -. e~soils occurred-on August 10 15 and 16 . The first attempt�to locate permeabl gu ' , 2000 with the drilling of four(4)boring excavated,to-a depth of 25-feet(Plate-1). Several of the holes were - tested for permeability.'however they all failed to achieve a.satisfactory percolation rate during ' preliminary percolation testing. At.this time, work on the project was stopped. On July 10 and 11, 20011,work resumed to locate suitable soilsirisout�h of the stor �� These borings located a series of thin sandy silt iayers which showed .` some some potential during preliminary testing.' Ted Norgard,of SJC PHS-EHD,observed .� the actual percolation tests. Unfortunately,the percolation rate slowed during the four hour . percolation test and all the tests failed. ' - On August' 1-12, and 3, 2001,.three 25-foot borings and one 3.5 foot boring was drilled on . the property.,,A 25 foot boring and a,3.5 foot boring was drilled near the existing milk barn septi c.system,two other 25 foot borings were drilled westof the July,10 and 11 borings. These borings also failed to achieve a satisfactory percolation rate during preliminarytesting. Table —' presents a summary of the standard SJC PHS-EHD ercolation.tests observed by SJC PHS-EHD.. Y