Laserfiche WebLink
<br />~- <br />C"') <br />('oJ , <br />N TABLE l.--Particle-size data for sediment cores from cluster-well sites <br /><-, <br />~,j [Categories containing at least 20 percent of total sample are in bold print] <br /> Site and Percentage in each Wentworth particle-size categoryl <br /> depth Omvel Median <br /> interval (feet Sand particle <br /> below land size (milli- Overall <br /> surface) Clay Silt Fine Medium Coarse Fine Medium meters) classification,' , <br /> ,.... <br /> W0035N <br /> 3-6 6 83 10 1 0 0 0 0.015 silt <br /> 6-9 12 54 33 I 0 0 0 ,053 silt <br /> 12-23 23 37 6 5 13 9 7 ,036 silt <br /> 26-30 13 38 41 4 2 2 0 ,065 fine sand <br /> WG053N <br /> 5-8 4 76 17 3 0 0 0 0,034 silt <br /> 11-14 15 27 40 4 6 7 1 .10 fine sand <br /> 14-17 18 44 14 9 12 2 I ,028 silt <br /> 17-20 10 2S 26 4 9 10 16 .12 fine sand <br /> 23-26 16 26 39 4 7 8 0 ,10 fine sand <br /> W0062N <br /> 3-4 14 61 20 3 1 1 0 0.025 silt <br /> 5-6 4 42 48 3 3 0 0 .10 fine sand <br /> 11-12 4 53 17 6 11 8 1 .055 silt <br /> 15-16 3 26 20 7 12 27 5 .26 medium sand <br /> 22-23 6 13 64 5 6 6 0 .13 fine sand <br /> 32-33 30 57 10 2 1 0 0 .01 silt <br /> WOO71N <br /> 8-9 17 21 5 14 17 19 7' 0.38 medium sand <br /> 1 WenlWorth Classification System: clay. less than 0,004 millimeter; silt, 0,004 to 0.062 millimeter; fine sand. <br /> 0,062 to 0.25 millimeter; medium sand. 0.25 to 0.5 millimeter; coarse sand, 0.5 to 2 millimeters; fine gravel. 4 to 8 <br /> millimeters; and medium gravel. 8 to 16 millimeters, <br /> <br />Three slug-test procedures were used to estimate hydraulic conductivity at cluster wells in the study <br />area. These techniques were applied to measurements of water level made after an instantaneous slug of <br />water was injected into selected wens. The method described by Rvorslev (1951) assumes isotropic flow <br />to a piezometer open only to a small interval of the aquifer, The aquifer is assumed to be homogeneous <br />and infinite in extent in both the horizontal and vertical directions, The alluvial aquifer and water are <br />assumed to be incompressible, and fluctuations in the water table due to the slug of water are assumed to <br />be negligible also, The method of Bouwer and Rice (1976) was developed for unconfined aquifers and <br />partially penetrating wells (well screened through only a part of the aquifer), Calculations are based on the <br />Thiem equation for steady flow to a well, and assume a homogeneous and isotropic aquifer. The aquifer <br />and water are assumed also to be incompressible. Finally. Cooper and others (1967) developed a slug-test <br />method for fully penetrating wells in confined aquifers. Their method assumes radial flow to the well from <br />a homogeneous. isotropic aquifer in which the aquifer and water are compressible. <br /> <br />-11- <br />