Air sparging has been used for several years as an in situ technique for removing volatile compounds from contaminated ground water, but few studies have been completed to quantify the extent of remediation. To gain knowledge of the air flow and water behavior around air injection wells, laboratory tests and model simulations were completed at three injection flow rates (62, 187, and 283 lpm) in a cylindrical reactor (diameter ‐ 1.2 m, depth = 0.65 m). Measurements of the air flux distribution were made across the surface of the reactor at 24 monitoring locations, six radial positions equally spaced along two orthogonal transects. Simulations using a multiphase flow model called T2VOC were completed for a homogeneous, axisymmetric configuration. Input parameters were independently measured soil properties. In all the experiments, about 75 percent of the flow injected exited the water table within 30 cm of the sparge well. Predictions with T2VOC showed the same. The averages of four flux measurements at a particular distance from the sparge well compare satisfactorily with T2VOC predictions. Measured flux values at a given radius varied by more than a factor of two, but the averages were consistent between experiments and agreed well with T2VOC simulations. The T2VOC prediction of the radial extent of sparging coincided with the distance out to which air flow from the sparge well could not be detected in the reactor. The sparging pattern was relatively unaffected by the air injection rate over the range of conditions studied. Changes in the injection rate resulted in nearly proportional changes in flux rates.

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Research has shown that students are preparing less for class using traditional forms (i.e.: reading textbooks) and, as a result, are not ready for class. Providing additional support materials to be reviewed before class in a format preferred by first-year engineering students may improve student readiness and performance. Therefore, in addition to traditional reading assignments, students complete pre-lesson activities such as video tutorials, online quizzes, or short "how to" exercises.In response to a student survey given in fall 2013 on current course preparation and desired formats, materials were developed in spring 2014 for course ENG1101. The pre-lesson activities focused on videos and on-line quizzes for MATLAB. Results from the pilot suggest slightly positive improvements in readiness and performance. Therefore, pre-lesson activities have been expanded to include additional topics.Video tutorials, online quizzes, and additional pre-lesson activities were developed for the additional topics which included technical communication, spreadsheets, problem solving, statistics, as well as the MATLAB lessons. The pre-lesson activities were incorporated in course ENG1101 in fall 2014. Students were assigned the pre-lesson videos in addition to the traditional reading assignment (textbook reading to prepare for class) with several levels of encouragement to prepare for class ranging from no encouragement to required quizzes or short assignments to be completed before class. At the end of the semester, these students completed a survey similar to the pilot survey regarding what they did to prepare for lessons and what additional support materials they would like to have. This paper will focus on the impact of the pre-lesson activities, including short video tutorials and on-line quizzes, on student readiness and performance. The responses on the student preparedness surveys for the different groups will be compared to see if the developed materials improves student readiness. The three groups were: No change to the current course format  Students could watch the videos  Students could watch the videos and they had to complete a short, on-line quiz based on the video content. Additionally, student learning will be assessed by comparing performance on exam scores pertaining to topics for the fall 2013 traditional reading group and the fall 2014 experimental group.