QUANTIFYING METAL OXIDE LEACHING TO ASSESS THE VIABILITY OF USING GLASS CULLET FOR SHORELINE RESTORATION

Glass cullet (recycled or broken glass) is being investigated as a viable alternative to dredged sediment in beach and river recovery processes after severe weather events. Dredging of the ocean floor to replace lost sediment on beaches has many negative impacts, such as disturbance of marine ecosystems and death of both animal and plant life near coastlines. The main concern with using glass cullet for sediment replacement is the potential leaching of metal oxides that are used to color bottles. Common examples of these metals are iron, cadmium, and manganese within amber glass bottles or iron, chromium, and copper within green glass bottles. These metals can be toxic to human and marine life if leached out of the glass cullet. In previous work, samples of glass cullet were left in deionized water or salt water for 5 weeks at room temperature to determine if a detectable amount of leaching would occur. Initial findings using Atomic Absorption Spectroscopy (AAS) indicated a detectable amount of chromic oxide after five weeks. This research project continues initial work on the outcomes of using glass cullet as a replacement sediment supply, with an emphasis on long-term environmental impacts. The purpose of this phase of the project is to mimic coastal environmental conditions by including agitation and gradual changes of temperature to better understand their impact on the possible leaching effects from cullet.