The NRW guidance provides a link to the Air Pollution Information Service (APIS) website which can give you information on the background values of ammonia at your planned development site.
Mae canllawiau CNC yn darparu dolen i wefan y Gwasanaeth Gwybodaeth am Lygredd Awyr a all roi gwybodaeth i chi am werthoedd cefndir amonia ar eich safle datblygu arfaethedig.