The following hazards are considered risks:
aggressive substances – including inorganic and organic acids, alkalis, organic solvents and inorganic chemicals, such as sulphates and chlorides (C2.23a);
combustible fill – including domestic waste, colliery spoil, coal, plastics, petrol-soaked ground, etc (C2.23b);
expansive slags – e.g. blast furnace and steel-making slag (C2.23c);
floodwater affected by contaminants – substances in the ground, waste matter or sewage (C2.23d).