It's an offence to store, treat, and dispose of, waste unless it's done in accordance with an environmental permit issued by the Environment Agency. Section 33 of the Environmental Protection Act 1990 controls the storage, treatment and disposal of waste.
It's also an offence to dispose of waste in a manner likely to pollute the environment or harm human health. This part of the law is most commonly applied to the burning of waste. These are very serious offences, and each one carries a maximum penalty fine and a prison term.