UK Government has primary legislation powers (for England and Wales).
The Department of the Environment (NI) Planning and Environmental Policy Group (PEPG) is responsible for environmental legislation in Northern Ireland.
The Northern Ireland Environmental Agency (NIEA) currently takes the lead on advising on, and implementing, environmental policy and strategy. NIEA has the waste regulatory role as legislated for in the Waste and Contaminated Land (NI) Order 1997, and the Waste Regulations (Northern Ireland) 2011
Devolved to SG; some powers reserved by Westminster.
The Scottish Environmental Protection Agency (SEPA) has a statutory duty to protect the environment and human health from the effects of waste management and disposal. SEPA has both regulatory and enforcement functions.
The Government of Wales Act 2006 enables the Welsh Assembly to bring forward its own programme of legislation, subject to scrutiny and approval by the National Assembly for Wales.
Following a referendum in 2011, the Assembly can now make laws for Wales on subjects for which the Assembly and the Welsh Assembly Government are already responsible, without needing permission from the UK Parliament first.