Journal of Undergraduate Research


multiple regression variable selection, biochemical oxygen demand, BOD


Physical and Mathematical Sciences




Biochemical Oxygen Demand (BOD) is used to measure of the amount of oxygen required by aerobic bacteria and other microorganisms to stabilize decomposable organic matter. It is run as a laboratory based biodegradation test and relies upon the presence of a thriving microbial community that may be naturally present in the sample or artificially introduced by addition of a seed, commonly a known volume of sewage effluent of known BOD. A standard BOD test is run in the dark at a temperature of 20 degrees Celsius for 5 days. This is defined as a five-day BOD (BOD5), which is the oxygen used in the first five days. Although BOD is the current standard, this test is not only long (five days), but it also be cost-prohibitive in developing countries due to the cost of the equipment required. Excitation Emission Matrix (EEM) is a test that measures the fluorescence of a water sample and is created by simultaneously scanning excitation and emission wavelengths through an aqueous sample. EEM takes less than two hours to produce results. So, this procedure could be used to monitor water treatment processes in real time, which isn’t possible with BOD5 because of the length of the procedure. However, EEM is difficult to interpret since it produces a 30×40 matrix with 1200 values. A visualization of an EEM is shown. Our data consists of EEM matrices and corresponding BOD measurements from four sites in the Provo waste water treatment plant and 3 sites from the Orem waste water treatment plant.