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GeologlcalTeckrilcslnG Page 4 ' Site Conceptual Model Report Mara Property Project No 7012 August 23,2004 ' San Jose Sheet Division of Mines and Geology, 1966 The following section discusses the ) g subjective field observations and geology documented during this investigation based on the interpretations of various field geologists ' • In boring MW-1, WJM described the soils as predonunantly clayey with some silty clays, gravelly sandy clays and sandy clays The clays range in color from brown to brown-grey with blue clays noted at 49 and 58 — 67 feet bgs A thin one foot thick sand unit was noted at 35 -36 feet bgs • Boring MW-2 was logged by WJM as containing clays similar to MW-1 The soils in this boring differed in that the clays were tan or reddish brown in color A sand layer was noted at 39—40 feet bgs and blue clays were noted at 1 - 2 feet and at the boring terminus at 86 feet bgs • WJM logged boring MW-3 as containing clays similar to above Clayey silt layers are ' present at 46 and 69 feet bgs Blue colored clays were not noted in the borehole • In boring MW-4, WJM described the soils as clayey with some sandy-silty clays and sandy clays A sand-gravel unit was noted 45-46' feet bgs and silts were present from 61 ' -- 65 feet bgs The clays range in color from tan to brown, brown-grey with blue clays noted at 49 and 58 — 67 feet bgs. A thin one foot thick sand unit was noted at 35 -36 feet bgs MGTI logged the remainder of the borings- ® GTI logged boring MW-5 (MW-105) as predominantly clayey with minor silty clays, silts, and sands Sand layers were noted at 36 and 50 feet bgs, while silts units are present ' at 5, 45 and 55 feet bgs The soil ranged in color from brown and grey hues to dark grey- green The green layers were at the deeper portion of this boring from 90—95 feet bgs • Boring MW-6 contained predominantly clayey soils as above with some sand and silt ' layers A silt layer is present at 5 feet bgs, and a sand layer containing pebbles to 2 cm is present at 40 feet bgs Soil colors ranged from brown and grey to olive • Boring MW-7 contained predominantly silty soils with less clay encountered than to ' previous borings The sediments ranged from grey-green and grey to brown in color A gravelly clay layer is present at 5 feet bgs • --In--boring MW-8, the sediments are predominantly fine grained- silts and clays,-similar to ' MW-7 Some very fine to fine sand units are present at 25, 35 and 65 feet bgs • Boring MW-104 sediments ranged from browns to red-browns to various hues of grey color Sand layers ranged from very fine to medium, and sediments occasionall ws` contained CaCO3 nodules, black organics and iron oxide staining-�1�'�u iv4 l y _54oLl I a 35 l ' • Boring MW-106 was free drilled to 75 feet bgs due to its proximity to MW-6 Below 75 00`� gs feet, sandy soils were first encountered and underlain by silts then clays at 95 feet bgs Und These soils ranged from brown to grey in color and the sands were very fine to very coarse in size