They came into force on the 6th of May 2009 in Wales and placed obligations on many businesses to prevent, or put right, any environmental damage they are responsible for.
Daethant i rym ar 6 Mai 2009 yng Nghymru gan osod rhwymedigaethau ar lawer o fusnesau i atal, neu unioni, unrhyw ddifrod amgylcheddol y maent yn gyfrifol amdano.