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CALCULATION OF HYDROCARBON DESTRUCTION BY THE VE SYSTEM <br /> Hydrocarbon concentrations found in the influent samples are multiplied by the volume <br /> of air produced in one day to calculate the pounds (lbs ) per day that have been extracted <br /> by the VE system <br /> The lab reports the Concentrations (C) of the air sampling in g/liter The first step is to <br /> convert this value to lbs/cf(pounds per cubic foot) <br /> 1 ug/l x 0 000001 g/ug x 0 0022051/g x 28 321/cf= 0 000000062 1 lb/cf <br /> The volume of air produced in one day, equals the flow rate (Q) x the time of flow <br /> V = Q x T = cf/day = cf/min x 1440min/day <br /> The volume must be corrected to standard temperature and pressure(STP) <br /> P = Pressure = 29 92 in Hg @ STP <br /> V = Volume cf <br /> T = Temperature in degrees above absolute Zero = 491 58°R @ STP <br /> Using the Ideal Gas Law P I V I/T1 = P2V2/T2 <br /> Solving for V2 =P I V 1 T2/P2T 1 <br /> V 1 = Q cfm x 1440 min/day <br /> T2 = 491 58°R T1 = 459 58 + T°F Air <br /> P2 = 29 92 P 1 = Air Pressure - System Vacuum <br /> V2 = Q cfm x 1440 min/day x 491 58'R/(459 580 + T°F) x P1/P2 <br /> X lb/day = C ug/1 x 0 0000000621 lb Uug cf x Q cf/min x 1440 min/day x <br /> 491 58°X/(459 580 + T°l~) <br /> Q for the Influent sample = The influent flow rate This will be calculated from the <br /> readings from the orifice plate flowmeter <br /> Q for the Effluent =The influent flow rate + air dilute flow rate <br /> EXTRAPOLATION OF VE PILOT TEST RESULTS <br /> The sample results from the pilot test will be used to determine <br /> 1 The expected poundage of recovered hydrocarbons <br /> 2 The most beneficial vapor treatment system type <br /> 3 The probable effective parameters and run time of this type of treatment system <br /> 4 Effect of vapor extraction on groundwater bio-remediation <br /> FOLLOW-UP MEASUREMENTS OF DISSOLVED OXYGEN <br /> After the completion of the active portion of the air sparging and VE pilot test, dissolved <br /> oxygen concentrations will be measured in water samples from the trench after the air <br /> flow is stopped and then again on day, 2, 4, 8, 16 and 32, in order to determine the <br /> oxygen consumption rate <br /> 12 <br />