Laserfiche WebLink
u <br />11 <br />76-301 <br />Sullivan Septic Service -2- December 3, 1976 <br />to our laboratory for verification of the field classifica- <br />tions by a Soils Engineer. Representative samples will <br />remain in this office for a period of 60 days to be available <br />for your examination. <br />The boring was probed 1/2 hour after its completion to check <br />for the presence of groundwater. The boring was also re- <br />checked prior to leaving the site on November 29, 1976. <br />The percolation tests were run in 6-inch diameter holes <br />drilled to an approximate depth of 36 inches, in accordance <br />with the procedures recommended by the Minnesota Department <br />of Health (MDH). In accordance with these procedures, the <br />bottom and sides of the holes were scratched with a knife <br />blade to remove any smeared soil surfaces and to provide a <br />natural soil interface into which the water may percolate. <br />Two inches of coarse sand were then placed in the bottom of <br />the holes to prevent scouring. The holes were then care- <br />fully filled with clear water to a minimum depth of 12 <br />inches over the top of the sand layer and allowed t soak <br />overnight with percolation tests being conducted tK. following <br />day. <br />RESULTS: <br />The Log of Soils encountered in the borings and the water <br />level observations are shown on the attached Log of Boring <br />sheets. <br />The boring generally encountered lh feet of a silty clay <br />topsoil at the surface underlain by silty clayey sand and <br />clayey sand glacial till to approximately the 11h-foot <br />depth. This material was in turn underlain by a fine to <br />medium -grained glacial outwash sane: to the 14-foot depth. <br />Glacial till clayey sand was then encountered to the 2S-foot <br />termination depth of the boring. Silty clayey sand glacial <br />till was the predominant soil encountered in each of the <br />percolation tests. <br />In probing the boring 1/2 hour after completion, groundwater <br />was encountered at the 21-foot depth. Approximately 1h hours <br />later the bore hole was again checked for the presence of <br />groundwater and it was noted to be at the 20-foot depth or <br />at an elevation of 942.0. Because of the cohesive nature of <br />the soils encountered, considerable time required in <br />order for the groundwater to stabilize in the boring. It <br />does not appear that the groundwater levels were completely <br />ORAUR" <br />ENGINEERING TESTING <br />