| Royal St. David's Golf Club Limited | | | Environmental Violation | 2022 | UK-NRW | £0 |
| SGG Developments Limited | | | Environmental Violation | 2022 | UK-NRW | £0 |
| Teifi Trout Association | | | Environmental Violation | 2022 | UK-NRW | £0 |
| Tu Mewn Cyfyngedig | | | Environmental Violation | 2022 | UK-NRW | £0 |
| Welsh Tyre Recycling Services Limited | | | Environmental Violation | 2022 | UK-NRW | £0 |
| Ammanford Recycling Limited | | | Environmental Violation | 2023 | UK-NRW | £0 |
| Enzos Homes Ltd | | | Environmental Violation | 2023 | UK-NRW | £0 |
| New Horizons Biofuel and Animal Beddings Co Ltd | | | Environmental Violation | 2023 | UK-NRW | £0 |
| Ty Mawr West Limited | | | Environmental Violation | 2023 | UK-NRW | £0 |
| A & D Evans & Sons | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Abertawe Metals Recycling Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| ACD Skips Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| AJ & CJ Powell & Son | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Alun Griffiths (Contractors) Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Anglesey Turf Company Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Apple County Cider Co Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Arch Services (UK) Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| B E Baker & Sons Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Balfour Beatty Civil Engineering Ltd | Balfour Beatty | construction and engineering | Environmental Violation | 2020 | UK-NRW | £0 |
| Barratt Homes South Wales | Barratt Developments PLC | real estate | Environmental Violation | 2020 | UK-NRW | £0 |
| Barratt Homes South Wales | Barratt Developments PLC | real estate | Environmental Violation | 2020 | UK-NRW | £0 |
| BDC Aggregates | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Befesa Salt Slags Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| BG Carey & Sons | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Bob Gay Plant Hire Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Breedon Group plc | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Browns Recycling Group Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Bryn Aggregates Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Bryngwyn Hall | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Carmarthen Bay Holiday park | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Castle Dairies Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Celtic Energy Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Celtic Recovery Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Clive Hurt (Plant Hire) Limited | | | Environmental Violation | 2020 | UK-NRW | £0 |
| CS Grabhire and Groundworks | | | Environmental Violation | 2020 | UK-NRW | £0 |
| D & E Haulage | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Dai Warlow Agri Contractors | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Delta Property Cardiff Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Dragon LNG Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| DW Cummings Ltd | | | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
| Dwr Cymru Cyfyngedig | Dwr Cymru Cyfyngedig (Welsh Water) | utilities and power generation | Environmental Violation | 2020 | UK-NRW | £0 |
