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Mr Rob Anderson 23 July 2009 Page 2 may differ somewhat from what is shown on the logs due to the inexact nature of auger sampling and the occurrence of transition between soil layers. Also, and most importantly, be advised that soil profiles not in the vicinity of the borings may vary. The number of borings (3) and general location were determined by you and those with whom you were working (City officials). The borings were placed generally in this pattern, with minor adjustments made due to obstacles, access conditions, results of the investigation as it proceeded, etc. Final boring locations are shown on the attached sketch. In addition, the bore holes were marked in the field with lath. Ground surface elevation at each boring location was determined using an engineer's level and referenced to the rim of a sewer manhole in the street in front of the existing residence, located schematically as shown on said attached sketch. This bench mark has, according to information on file with the City of Roseville, and assuming that the manhole casting has not been raised due to any street overlay, a reference elevation of 897.50. Accuracy of this should not be taken as any greater than the methods used would imply. The borings indicate varying amounts of fill or otherwise disturbed soil on the site, an expected condition given likely general site grading for residential development. This fill is highly variable, but generally is composed of clay loam and various plasticities sandy loams, plus loamy sand (prevalent at surface level), with varying gravel content and a trace of debris, with virtually no pattem as to layering, consistency, etc. These soils would generally have a low infiltration rate. More importantly, due to their nature of being fill or otherwise disturbed, they should not be trusted for the proposed purpose. One deposit of naturally occurring clay loam was found from 5'/Z' to 8' in Boring 2. Commencing at 6'/2', 8' and 9'/2' (approx elevations 892'/Z, 888'/2 & 886'/Z) at Borings 1, 2& 3, respectively, are naturally occurring sands seemingly suitable for the intended purpose of infiltration. Genercrlly, it appears that the onset surface of this sandy material slopes downward to the westnorthwest. The first material is a gravelly loamy sand (percent passing the #270 sieve just over ] 0%) which becomes cleaner with depth, becoming sands of varying gradations with loam (percent passing the #270 sieve under 10%} and varying gravel contents These are coarse alluvium soils (laid down by relatively fast moving water). One exception to this is a deposit of clay loam found at depth in Boring 1. This material was not found again, even at deeper elevations, in other borings. Soil moisture contents ofthe fill material is below normal at first, becoming normal with depth. The sands were of normal moisture content as well. Groundwater was not found in any of the borings after a standard period of observation. True groundwater is probably a great distance lower. However, please be informed that groundwater can still occur and fluctuate in unpredictable manners due to changes in precipitation patterns, area development pattems, etc, that were indeterminable within the time frame, scope and budget allowed in this investigation. Indicated results are for the time and conditions of testing only. It should be pointed out that the naturally occurring clay soils (at depth in Boring 1 and at an intermediate depth in Boring 2) are techru_callv saturated (all pores filled with water). They appear to be not waterbearing (capable of releasing this water). This is a normal condition for naturally occurring clay soils. 1 To aid in the assignment of�page rates of the upper soil, gradat�tests were run, two on