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CLOSURE REQUEST 5-31-94 <br /> . from one aquifer (sand/gravel formation) to the next . An <br /> overdraft situation in this area has enhanced this downward <br /> migration and is associated with the steady decrease in ground <br /> water quality due to the intrusion of the more saline water of the <br /> Delta infiltrating the various shallow aquifers . <br /> a) & b) Local gradient evaluation and seasonal <br /> fluctuations. <br /> Depth to ground water measurements show that the aquifer beneath <br /> this site has fluctuated at various wells from 9 to 16 feet, <br /> ranging from 52 to 60 feet below the suface at the northwest <br /> corner of the site (MW6) , from 44 to 60 feet below the surface at <br /> the northeast corner of the site (MW4) , from 51 to 60 feet below <br /> the surface at the southwest corner of the site (MW3) , from 48 to <br /> 62 feet below the surface at the southeast corner (MW2) and from <br /> 51 to 61 feet below the surface near the center of the site <br /> (MW1) . Flow direction without the influence of VES, fluctuates <br /> from the northeast to the southeast, see Table 2 and Figures 4A <br /> and 4B <br /> c) Aquifer characteristics and d) Soil pe=eab12ity <br /> BOUWER AND RICE SLUG TESTS <br /> On November 21, 1990, Bouwer and Rice Slug Tests were performed <br /> on the existing monitor wells at former Regal Station 604 . The <br /> following "K" values (hydraulic conductivity) were calculated for <br /> the wells -an reported in the January 24 , 1991 Update Status <br /> Report #5 • MW1, 1 58 feet/day; MW2, 0 39 feet per day, MW3 , 0 . 03 <br /> feet per day; MW4 , 0 21 feet per day; MW5, 0 . 51 feet per day; and <br /> MW6, 1 . 99 feet per day An error has been discovered in the <br /> program used to calculate the above K values The K values for <br /> the wells have been recalculated The corr cted K va ues are <br /> MW1, 14 72 feet /day; MW2 , 2 32 feet/day, MW3 , 0 . 39 feet/day, <br /> MW4 , 4 53 feet a 5 6 feet da and MW6 23 feet da s <br /> A endix H. These K values indicate a fine sand aquifer trending <br /> southeast from MW6 towards MW1, MW5 and then south, southeast to <br /> MW7, with silty to sandy clay banks to the northeast at MW4 and <br /> MW2 and to the southwest at MW3 . <br /> SLUG TEST CALCULATIONS, ETC. <br /> CALCULATING K (Hydraulic conductivity) <br /> K is calculated using the following formula . <br /> K = re2 ln (Re/rw) / (2Le) 1/t ln (yo/yt) <br /> rc = The radius of the well <br /> rw = The radius of the bore hole. <br /> • re = The equivalent radius of the well . <br /> pagel7 <br />