fig1 illustrates a storage tank 20 with the bottom of the tank 22 resting on a base 24 with a seal 26 around the periphery of the base 24 . a dike 28 and moat 30 surround the tank 20 to retain any spills that may occur . within the base 24 one or more perforated conduits 32 are in place . the base 24 can be formed of any suitable material , such as soil , sand , gravel , crushed rock and the like . the seal 26 may not be necessary in all cases . if the base 24 is very porous , then a seal 26 probably will be necessary . the seal 26 may be plastic , metal , or other non - porous materials . fig2 illustrates one embodiment of a seal 26 in which the base 24 has a layer of grout 34 around the periphery , and a sealing skirt 36 over the group 34 . the perforated conduit 32 passes through the skirt 36 and grout 34 into the base 24 below the bottom of the tank 22 . turning now to fig3 a segment of perforated conduit 32 is shown in cut - away detail . the conduit 32 has a wall 38 , a lumen 40 and one or more perforations 42 . the conduit 32 may be formed of metal , plastic or other suitable material . the perforation ( s ) 42 may be in the side , as illustrated , or in the tip ( not illustrated ), or both . in use , gas or fluid is injected under pressure into the conduit 32 , illustrated by arrow 44 , and through the lumen 40 of the conduit , and out the perforation ( s ) 42 into the base . this flow is illustrated by arrow 42 . in the preferred embodiment , gas is injected with sufficient pressure to force flow through the perforation ( s ) 42 . any suitable commercially available gas or fluid may be used . the injected gas or fluid noted above , passes into the base 24 beneath the tank 20 . if there is a leak in the bottom of the tank 22 , the increased pressure beneath the tank will either cause the injected gas or fluid to pass through the leak , or it will disturb any equilibrium that may be stopping or decreasing flow through the leak , so that there is increased flow through the leak . this flow through the leak creates vibrations , i . e . an acoustically detectable event , which may be detected by acoustic sensors . fig4 illustrates the above sequence . a perforated conduit 32 is inserted into the base 24 beneath the tank 20 . the conduit 32 is generally horizontally placed in a parallel relation to the bottom of the tank 22 . the tank 20 has liquid in it with at a certain level 50 . gas or fluid is injected under pressure into the conduit end 52 , this flows through the conduit 32 and out the perforations 42 in the conduit into the base 24 area . in fig4 a line of bubbles 54 is shown flowing from the perforation 42 in the conduit 32 through the base 24 to a leak 56 in the bottom of the tank . the gas is then shown flowing through the leak 56 as another series of bubbles 58 within the liquid 60 in the tank . attention is now directed to fig5 . this illustrates the tank 20 , on a base 24 , with a conduit 32 beneath the tank . acoustic sensors are also shown . these may be internal sensors 62 within or below the liquid level 50 inside the tank ; or , they may be external sensors 64 placed outside the tank 20 . various combinations and numbers of sensors may be used . sensors may be of any available type , such as piezoelectric , microphones , and the like . the sensors 64 and 62 are attached by cables or wires 66 to an amplifier 68 , an analyzer 70 , and a display 72 . if my invention is only used to screen for leaks , then only 1 or 2 sensors may be needed , and no analysis or display is needed , since one is only screening to see if there is a leak . however , if one wishes to locate the site of the leak , a plurality of sensors will be needed with amplification and analysis of the signals from the sensors and display of the results . once a leak is detected and located , the user may wish to seal the leak . while the tank can be drained , and conventional repair methods used , this invention offers an alternative . this is illustrated by fig6 . once the leak 56 is located , a probe 74 is inserted beneath the tank 20 in the base 24 in a horizontal position . the probe 74 has a perforation 76 either in the side or tip of the probe . the probe 74 is positioned in the base 24 so that the perforation 76 lies below and near the leak 56 . a settable sealant is then injected under pressure through the probe 74 so that it is extruded from the perforation 76 and will flow into the area abutting the leak 56 and will seal the leak . this exuded sealant is indicated in fig6 at 80 . i have tested the above described pneumatic enhancement of acoustic emissions and found : ( 1 ) i have been able to detect leaks as small as 0 . 02 inches . ( 2 ) i have been able to detect leaks within 2 minutes of the start of the test . this is compared to several hours required in some other methods . further , this reduces the time of exposure to background noise . ( 3 ) i was able to detect leaks in spite of background noise . for example , in one case there was a sand blasting operation about 100 yards away with the air compressor 15 feet from the test tank , and i was still able to detect leaks . i did these tests in a tank with 18 inches of liquid contents . the plenum pressure under the tank can be varied in response to the acoustic output as needed . as noted in my prior u . s . pat . no . 4 , 896 , 528 , one way of placing the perforated conduit and / or probe beneath the tank is to use the &# 34 ; hole - hog &# 34 ; ( reg . trademark ) available from cimmac , inc ., 4251 south 76th east avenue , tulsa , okla . 74147 which is used for drilling horizontal holes . while the invention has been described with a certain degree of particularity it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure . it is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification , but is to be limited only by the scope of the attached claim or claims , including the full range of equivalency to which each element thereof is entitled .