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Vermillion Ranch Limited Partnership/Surface Water Impoundment 13659-RX. <br /> A, B-B, and B-C. Along the proposed dam centerline (B-4 thru B-6), these soils were generally <br /> saturated and N-Values ranged from 0 to 14 blows per foot of penetration. At the proposed <br /> spillway and southern embankment areas, soils in this stratum were above the groundwater <br /> level and in an unsaturated condition, with N-Values ranging from 6 to 40 blows per foot of <br /> penetration. Sieve analyses conducted on samples obtained from the silty/clayey sand indicates <br /> minus number 200 sieve fractions of 10.7 percent to 39.1 percent. Atterberg Limits tests show <br /> plasticity indices ranging from non-plastic to 12 percent. Soils within the old alluvial deposit <br /> have higher percentages of sand sized particles and lower plasticity than recent alluvium <br /> occurring near the surface of the Talamantes Creek floodplain. <br /> ' Sedimentary bedrock encountered at the site consists of very stiff to hard clay (weathered <br /> claystone) along the northern dam embankment and medium dense to very dense silty sand <br /> (weathered sandstone) along the southern dam embankment and spillway area. N-Values <br /> recorded in the bedrock ranged from 19 blows per foot to in excess of 50 blows per foot of <br /> penetration, with the lower N-values occurring near the bedrock surface where weathering has <br /> occurred. <br /> 1 Soil classification of proposed borrow soils were also conducted on surficial soils sampled by <br /> Mr. Robert Johnson. A summary of the laboratory test results are as follows: <br /> Sample No. S-1 & S-2 Composite S-3 & S-4 Composite <br /> - #200 Sieve Fraction(%) 66.9 68.4 <br /> Liquid Limit Non-plastic 28 <br /> Plasticity Index Non-plastic 11 <br /> Standard Proctor 109.0 109.1 <br /> Maximum Dry Density(pcf) <br /> Standard Proctor 11.4 15.4 <br /> Optimum Moisture Content(%) <br /> Groundwater Conditions <br /> Groundwater observations were made in each test boring at the completion of drilling. This <br /> information, along with cave-in depths of the drill holes, is recorded on the Final Logs in <br /> Appendix B. <br /> ' Groundwater was encountered at depths of 3.2 to 11.3 feet below ground surface in four test <br /> borings (B-3, B-4, B-5, and B-6) during drilling operations. After the test borings were <br /> ' complete and augers withdrawn, groundwater was measured at depths of 3.2 to 7.3 feet below <br /> the ground surface. We anticipate that groundwater surface elevation at the site is highly <br /> dependent on proximity and surface water elevation of Talamantes Creek. We also anticipate <br /> ' groundwater surface elevation will fluctuate with seasonal changes in precipitation, runoff, <br /> irrigation, and surface water elevation of Talamantes Creek. <br /> INBERG-MILLER ENGINEERS <br /> 6 February 26, 2009 <br />