§ Mr. Malcolm BruceTo ask the Secretary of State for the Environment if he has made an assessment of the levels of(a) metals and (b) harmful micro-organisms present in unpasteurised sewage sludge used as fertiliser; and if he will make a statement.
§ Mr. Trippier[holding answer 23 March 1990]: The levels of metals in sewage sludge vary depending upon local circumstances. When sludge is used in agriculture, producers must ensure that the metal concentrations in he soil resulting from use of sludge do not exceed the limits specified in the Sludge (Use in Agriculture) Regulations 1989 (SI No. 1263). Detailed records have to be maintained by the sludge producer and made available to Her Majesty's inspectorate of pollution, which is responsible for enforcement of the regulations. The regulations also require that sludge is treated before use to reduce its fermentability and content of pathogenic organisms. Advice on acceptable sludge treatment methods is contained in the code of practice for agricultural use of sewage sludge published by the Department in 1989.
§ Mr. Malcolm BruceTo ask the Secretary of State for the Environment what percentage of sewage sludge is pasteurised before final disposal; what action he is taking to increase this percentage; and if he will make a statement.
§ Mr. Trippier[holding answer 23 March 1990]: Apart from one small pilot installation in Yorkshire, there are no operational sludge pasteurisation plants in the United Kingdom. This process is not used to any great extent elsewhere in other countries and we have no plans to require more extensive use here.
§ Mr. Malcolm BruceTo ask the Secretary of State for the Environment what steps he is taking to extract plastic waste from sewage sludge; and if he will make a statement.
§ Mr. Trippier[holding answer 23 March 1990]: It is a condition of licences for the disposal of sewage sludge at sea that non-degradable materials such as plastics must be removed before disposal. Enforcement is a matter for the licensing authorities.
The code of practice for agricultural use of sewage sludge also recommends that non-degradable material 119W should be removed from sludge before spreading on the land. Sludge producers find it essential in any event to screen out such materials to ensure efficient operation of sludge stabilisation processes.