Mae’r perygl o lygredd yn dibynnu ar nifer o ffactorau ar y safle, gan gynnwys nifer y carcasau, y math o garcasau, sut cawsant eu claddu, daeareg y safle a dyfnder y lefel trwythiad.  Gan mai Cyfoeth Naturiol Cymru sy’n gyfrifol am ddiogelu ansawdd dŵr, dylid gwrando ar eu cyngor nhw wrth gladdu stoc.  Am ragor o wybodaeth, darllenwch Groundwater Protection: Principles and Practice (GP3). Ceir copi ohono yn:http://www.environment-agency.gov.uk/research/library/publications/144346.aspx
The risk of pollution is site-specific and depends on a number of factors, including the volume and type of carcasses, the method of burial, the surrounding geology and the depth of the water table. As Natural Resources Wales is responsible for protecting water quality their guidelines need to be considered when disposing of carcasses. For more detailed information please refer toGroundwater Protection: Principles and Practice (GP3) on the Environment Agency's website.