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o *../ December 18,2001 Job Number:LGO1-375 Page 7 Two (2) soil borings were drilled on the parcel to characterize the subsurface conditions and measure the percolation rate. Plate 1 identifies the locations where the soil borings and percolation tests were conducted. Essentially, a fairly homogeneous reddish brown clayey silt existed to a depth of 14 feet. The soil became a reddish brown sandy silty near 15 feet of depth. The maximum depth drilled was 15.7 feet. The soils were logged by grab sample from the auger. A shallow and deep percolation test were set adjacent to each other to measure the shallow and deep percolation rate of the soil. The shallow and deep percolation test borings were drilled utilizing a 6-inch diameter hollow stem auger. The two (2)holes were scarified to remove any smearing of clay caused from rotary auger drilling. The casing used for each test was 2-inch diameter PVC pipe with an open end on the top and bottom. Perforations were made on approximately the last 12-inches of the casing. Two (2) inches of"pea gravel"were placed in the bottom of the hole, the casing was installed, and one(1) foot of"pea gravel"was backfilled in the annular space. The percolation test borings were pre-soaked 24-hours prior to the test. A one(1)hour percolation test was conducted for the deep percolation test. The shallow test did not exhibit any percolation capability. Each test was conducted on November 16 2001, in accordance with the requirements of San Joaquin County Environmental Health Division. Each percolation test was observed by Mr. Ted Norgard Environmental Health Specialist of the San Joaquin County Environmental Health Division. The following table presents a summary of the percolation test. Table 4 Summary of Percolation Tests. Percolation Test No. Percolation Percolation Rate Comment Test Depth(ft) (minutes/inch) P-1,shallow 1.5 Not measurable Failed test P-1,deep 15.7 < 1.6 min/inch Passed test A satisfactory percolation rate was achieved in the P-1 Deep percolation test. Test P-1 Shallow did not a achieve a satisfactory percolation rate. A satisfactory percolation rate per County requirements is less than or equal to 60 minutes per inch(drop) for the shallow test or less than or equal to 30 minutes per inch (drop) for the deep test. A satisfactory percolation rate achieved in either the deep or shallow test or both tests is considered acceptable for use with jo¢eso r 1 Z � r