In Procureur de la République v Association de défense des brûleurs d’huiles usagées case 240/83 the ECJ confirmed that the protection of the environment is one of the essential objectives of the Community which may justify certain limitations on the principle of free movement of goods. This approach was upheld in Commission v Denmark case 302/86 concerning a Danish system for ensuring that all containers for beer and soft drinks were returnable, although the ECJ went on to say that the scheme in question could not be upheld since the environment could be adequately protected by a similar, less restrictive regime (see Section 5.8). It was also upheld in Commission v Belgium case C–2/90 concerning free movement of waste (see Section 5.5). In Hedley Lomas the UK ministry suspected that Spanish slaughter houses were breaching a Directive on the stunning of animals, and refused licences for the export of live sheep. The ECJ held that a Member State may not rely on the exclusions to free movement contained in Art. 36 (now Article 30) of the Treaty (protection of health etc.) if a Directive pursuing that objective has been adopted, even where there is no procedure for monitoring compliance or penalty for breach.