The chairman of the local residents' association has claimed that the plant, "has an infrastructure that is basically Third World technology." Residents have complained previously about the unsavory smells coming from the plant.
Edinburgh council have admitted that, "any raw sewage has human pathogens in it which has the capacity to make people ill", and have warned people to stay away from the shore. However, residents have complained that they weren't warned of the leak fast enough, and that some people may have come into contact with the waste.
According to the Guardian, "Large discharges of sewage can kill marine animals by starving the water of oxygen. The sewage is expected to break down in a matter of days, but chemicals such as hydrogen peroxide can be added to reoxygenate the water." :: The Guardian