Report/subsurface exploration/geotechnical review

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AET #22-00173- Page 3 of 10 SITE CONDITIONS Soi1s The log test borings and location diagram (Figure l) are included in the Appendix. The logs contain information concerning soil stratification, soil classification, geologic descriptions and relative moisture; the density or consistency are also noted, based on the Standard Penetration resistance (N-value, "blows per foot"). The boring logs only indicate the subsurface conditions at the sampled locations and variations often occur beyond the borings. Boring No. 1 was located in the footprint of the proposed garage addition. In this boring, we found about 5'/2 feet of fill; the fill consisted of a mixture of clayey sand, and sandy silt. Below the fill we found interbedded strata of naturally-occurring non-organic coarse alluvium and till to the boring termination depth of 21 feet. The granular soils consisted of silty sand and sand with silt and were of loose to medium dense consistency, with N-values ranging from 5 to 20. The cohesive soils consisted of sandy lean clay and clayey sand and were of a stiff to ve�y stiff consisiency, with N-values ranging from 13 to 20. Boring No. 2 was located off the northeast corner of the existing foundation. In this boring. we found approximately 10 feet of fill; the fill consisted of a mixture of sand, silty sand, clayey sand, and sandy silt. Trace roots were noted in the recovered samples. Below the fill, we found a layer of organic clay with sand to a depth of about ]2'/2 feet below grade. These organic soils were very soft to soft in consistency, with N-values ranging from weight of hammer to 4. Below the fill and organic soils, we found till to the boring termination depth of 31 feet. The cohesive soils consisted of clayey sand, sandy lean clay, and lean clay with sand and were of a soft to stiff consistency, with N-values ranging from 4 to ]0.