Laserfiche WebLink
^ _ � <br /> , <br /> This unit is underlain by at least 10 feet of light brown, ' <br /> micaceous, clayey silt ( Ml /Cl ) . This unit has low plasticity <br /> and varies from stiff to very stiff in consistency. It was <br /> logged as Ml /Cl in each of the three wells drilled for this <br /> program. <br /> As can be seen from the logs, the soils underlying the site <br /> are lithologically consistent over the area that was <br /> investigated. There are no major pinch outs, cut outs, or other <br /> stratigraphic discontinuities present. <br /> Soils samples were taken at 5 foot intervals with a Modified � <br /> California split spoon sampler. These samples were sealed with <br /> tinfoil , capped with plastic lids, sealed with tape and <br /> transported to California Water Labs of Modesto. The samples <br /> were analysed for Total Petroleum Hydrocarbons including BTX. No <br /> contaminahtes were detected during the lab analysis. <br /> ^+ - <br /> ' <br /> GROUNDWBIgg <br /> Monitoring wells were installed in each of the three borings <br /> drilled during this program. Factory slotted 2 inch PVC casing <br /> was installed in each hole. The slotted zone extended 20 to 25 <br /> feet �"below water table and approximately 5 feet above water <br /> �� <br /> table. Blahk casing was installed above the slotted zone, to <br /> ' , ^ <br /> / surf�ce. H gravel pack was installed in each well , using No. 4 <br /> [ <br /> ' sand, to 2 to 5 feet above static water level . A bentonite seal <br /> from 1 to 6 feet thick was then installed, capped by grout to the <br /> surface. A lockable christe box was then installed to protect <br /> the Well from tampering. Details of the well construction for <br /> ` each ��ell Are shbwn on the logs, in the well graphic column. <br /> Ground water occurs at shallow depths under water table <br /> conditions at this site. Water levels have been measured several <br /> times since the wells were installed on 11/5/87. The wells were <br /> measured on 11/5/87, just after they were installed; on 12/03/87; <br /> and on 12/21/87. <br /> The readings taken on 11 /5/87 were not used to determine <br /> ground water gradient, since the water table was most likely <br /> disturbed by drilling operations. Readings taken on 12/03 and <br /> 12/21 , were used to determine both ground water gradient and <br /> magnitude at the site. This was done in early 1988, by means of <br /> graphical three point problems. The solutions to these problems <br /> are as follows: <br /> 12/03 -- N 49. 5 W @ . 14 ft / 100 ft <br /> 12/21 -- S 82. 0 W @ . 29 ft / 100 ft <br /> As one can easily see, the ground water conditions changed <br /> greatly between the two readings. In addition to the change in <br /> direction and gradient of the water table, the water level rose <br /> about one foot between the first and second readings. <br /> _ _ 2 <br />