Introduction Risk is usually related to the uncertainty and undesirability of a potential situation or event. It can be defined as the likelihood of an event occurring and its consequence. Risk assessment is the process of evaluating risks and taking steps to either eliminate or reduce them by introducing control measures. To assist in decision-making, organisations implement a common tool known as a risk matrix. This report will be focusing on the application of the risk matrix in the port expansion proposal in the Great Barrier Reef and discuss its efficiency and limitations at defining levels of risks. In 1981, the Great Barrier Reef was declared a UNESCO World Heritage site attributed to its "outstanding universal value". The 344,400 km ecosystem comprises of over 500 species of reefs, corals and seagrass meadows, providing a habitat and main food source to over 1500 species of fish and abundant marine life. Due to its biodiversity values as well as indigenous, tourism, cultural and heritage importance, the Great Barrier Reef is highly protected (Great Barrier Reef Marine Park Authority 2014). However, the Federal Government 's approval to construct one of the world's largest coal ports near the Great Barrier Reef raises multiple environmental concerns for the natural monument. Potential damage to aquatic wildlife and depletion of habitats from short and long-term activities of coal deportation poses a number of hazards. These hazards will require risk assessment to ensure stakeholders understand the possible risks involved and decide whether to proceed with the development