Many large scale recycling and industrial operations have been outsourced to areas with cheaper labor in recent decades, causing high concentrations of inorganic contaminants in water near low-infrastructure villages. Because of how these recycling villages were introduced to modern industrialization, infrastructure to deliver and remove anything other than the material to be recycled can be very difficult to implement. The goal of this project was to model a way of removing dissolved and particulate contaminants from drinking water without the use of any exhaustible component, such as a filter or chemical treatment. I used ultrasonic sound to create sharp pressure gradients in water and force contaminants to coagulate along the axis of sound for easy removal by macroscopic physical means. To achieve the pressure gradient, sound with a frequency of 2.25 MHz was reflected back at its source from a ceramic acoustic reflector 6.02 cm away. The water was held in an acrylic housing with the ultrasonic transducer at one end and acoustic reflector at the other. The acoustic reflector was build using time in Los Gatos High School's ceramic class and a plastic mold that I designed and printed. The reflector was secured with an adjustable system using small components from Home Depot. Bacteria of three different shapes were used to test if the device I built caused pressure gradients large enough to affect particles of about 1 um in diameter. Light absorbance of the samples at 400 nm was used to determine the quantity of bacteria in water because it varies linearly with the quantity of bacteria. Samples had on average 4% more light absorbance on the bottom, 3% more in the acoustic field, and 2% more in ambient water after each trial, suggesting that the device built may have concentrated some bacteria within

the filament. However, settling of the bacteria played a slightly larger factor, and the data is not statistically significant. Larger variations appeared between the different shapes of bacteria, suggesting that the shape of the particles within the acoustic field plays a role in how the acoustic field affects them. This method of removing contaminants is expected to be increasingly effective when dealing with substances with densities dissimilar to that of water, and could be applied in many practical problems.