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+ k underground storage tank and accessoryPumpunit . The EHD does not believe that sufficient data exists to make a "no contamination" finding . In order to accomplish :hese tasks, EHD believes that the local direction of flow of the water inj`theaquifers should be determined . The only sure way to do; this is to measure precisely the standing fluid level in three or more nearby locations and to calculate the shape of the water table . Figures 1 , 2 and 3 show the slope of the underground water table on a regional basis ; however, +..'ne data is not as complete in the local area as on most of the map. The EHD C: has required that this water table slopel'fbe determined. They have also required that the water in the on ,"site water well be tested for contaminates and that its level be determined. If one knew that the water in this well' were in continuous hydraulic contact with that which i11 be found in monitoring we11s, then only two monitor ing } wells would be needed to determine the water table slope because this slope can be determined with 3 points . Inasmuch 'as this is not known, this report recommends that threel; monitoring wells be drilled as shown on Figure 4. Well No .4 1 is located in a down--slope water flow direction as deduced ,from the County maps and adjacent to Airport Way. Well No . 2 will be � located within 10 ' of the end of the tank excavation, in a 'r position where any leakage would likelylbe discovered. Well No . 3 will be located adjacent to Airport Way in a southerly direction; which possibly also could b'.e the direction of water flow. If, upon testing the water Bevel in the current wat::r well , it is found that the level obtained fits the pattern of the three monitoring wells . ,then this data will s also be utilized in determining the water table slope. Proposed Field Work Figure 5 is a type diagram for the proposed monitoring ' wells . Exact depths for each of the operations shown will not be known until the bore holes are drilled. A portable, truck mounted, hollow stem 'auger- drilling unit t will be used . A101' nominal size O.D. hole will be bored to an estimated 30 ' below ground level or, whatever depth is needed to penetrate the water table at 1least; 10 ' . 50 gallon ! drums with sealing covers will be on site for collection of all auger cuttings and any water bailedllfrom the wells . The cuttings and any water collected will be disposed of in a proper manner after the operation is concluded, the disposal methods will be dependent upon levels61f po'1lutants found . The wells will be cased with 4" screw-jointed PVC with the bottom 10 ' plus pre-perforated with . 02'" slots, blank nosed on bottom. The well bore around the perforated interval will be packed with # 3 sand or the equivalent as a filter i medium. A 2 ' -4 ' bentonite clay plug will ;l:be placed above the perforatirns , in the 4" pipe-borehole annulus, to act as a