These Regulations revoke and replace—the Nitrate Pollution Prevention (Wales) Regulations 2013 (S.I. 2013/2506 (W. 245)) which control the application of nitrogen fertiliser in nitrate sensitive areas, andthe Water Resources (Control of Pollution) (Silage and Slurry) (Wales) Regulations 2010 (S.I. 2010/1493 (W. 136)) which regulate the custody and control of silage and slurry and provided the design and construction standards applicable for its storage.