Source Zone Delineation Demonstration Report - Triad Resource ...

10.0U12-VP1 Pneumatic Response8.0Airflow (scfm)6.04.02.00.0y = 0.2491x - 5.3727R 2 = 0.952920 25 30 35 40 45 50 55 60Applied Vacuum (inches of water)Figure 5-29. Induced airflow at U12-VP1 as a function of applied vacuum for both blowers.5.2.2 TCE Vapor ConcentrationsThe SVE demonstration conducted in the suspected source zone at OU 12 focused on step tests forestimating TCE distribution within the vadose zone of the investigative area using a multiphase,multicomponent numerical model. During the step tests, the concentration of TCE in time was monitoredvia the on-site laboratory using DSITMS. Concentration data were obtained during each flow period onone-second intervals, resulting in thousands of discrete data points for each flow test conducted. A TCEtime series plot was generated for each vapor extraction well by combining the individual data sets fromeach flow period for each extraction well as shown in Figures 5-30 through 5-36. The cumulative TCEremoval during each step test and the corresponding extraction rate used during each flow period also areshown on Figures 5-30 through 5-36.The cumulative mass of TCE removed from the vadose zone during the vapor extraction operations at OU12 was estimated using the molar volume of an ideal gas pressure-corrected according to the followingequation:whereV RT (6)n PV = volume (L);n = number of moles of gas ;March 2003 5-43 OU 12 Demonstration ReportFinal