Laserfiche WebLink
Temperature Measurement Precision <br /> ,✓ the lank Monitor measures temperature change over the vertical height of the <br /> fuel In the tank. The temperature change measured by the Tank Monitor was <br /> compared to an array of thermistors placed along the length of the tank <br /> probe . Results of this comparlson showed a mean difference of less than <br /> 0019F. In a half filled 10,000 gallon tank this difference. corresponds to <br /> .004 gallons. These tests were conducted by Vista Research and are included <br /> on Attachment 11 . <br /> Conclusion <br /> In a 4 hour test the Tank Monitor can measure fuel level changes equivalent <br /> to Oo5 gal ./hr. and temperature change equivalent to .002 gal ./hr. Wt <br /> conclude therefore, that the Tank Monitor is capable of detecting releases of <br /> petroleum fuels In underground storage tanks at a rate of .05 gallons per <br /> hour and therefore meets the State of Californla regulations for underground <br /> storage tank testing. <br /> Ili ADJUSTMENT FOR VARIATIONS <br /> The State of California regulations also limit test methods tc, those which <br /> make certain adjustments . The Tank Monitor fulfills this reovirement aS <br /> outlined below. <br /> Vapor Pockets <br /> The Tank Monitor test protocol does net recuire overfill and is therefore not <br /> affected by vapor pockets . <br /> Temperature Stratification <br /> temperature stratification is accounted for by using ultrasonic te.chneloey .to <br /> measure average temperature change over the vertical height of the product . <br /> Thermal Expansion and Contraction ' <br /> Effects of thermal expansion and co•.trw 1 on are accounted for in two (2) <br /> wu) 5 : <br /> (1 ) lest protocol calls for waiting 12 hours after the last delivery thus <br /> minlmlzing temperature Instability. <br /> (2) The Tank Monitor software is programmed to disregard test data If fuel <br /> temperature change rate exceeds .05°F per hour . <br /> Evaporation and Condensation <br /> Evaporation and condensation effects are accounted for by filling the tank in <br /> that surface area exposure Is minimal and by waiting 12 hours after the last <br /> delivery before conducting the tests. <br />