Vol. 576 No. 2
201 Mr. R. Bruton asked the Minister for the Environment Heritage and Local Government if he has carried out a health and safety study of the environmental hazards of composting on a substantial scale; if he plans to issue guidelines regarding the precautions which should be taken in relation to composting operations; and if he will make a statement on the matter. [29433/03]
Composting is widely acknowledged as a natural process whereby organic waste is decomposed by the action of micro and macro-organisms in the presence of oxygen to produce a humus-like material. Under appropriately prescribed conditions, including suitable site selection criteria, the controlled composting of organic and green waste is internationally accepted as a long established, well-proven and broadly acceptable method for the treatment and recovery of biodegradable waste, resulting ultimately in a beneficial and useful end product, that is, compost.
Bioaerosols, air-borne micro-organisms, including pathogenic bacteria and fungal spores, arise in many natural environments including lawns, farms and wooded areas. However, the operation of large-scale composting facilities may, in the absence of adequate precautions, give rise to the production of odours, volatile organic compounds and the release of bioaerosols in the immediate vicinity of such facilities. The main source for these bacteria and fungal spores at these installations may occur during mechanical agitation of the compost windrows, in activities such as screening, shredding and turning. Notwithstanding this, measures can be taken to reduce the potential health and safety risks associated with composting and may include: controlled blending-mixing of the raw material to provide a uniform fabric with a high porosity during the composting process; controlled turning of the windrows, including restrictions on the extent of turning operations consistent with the need to maintain adequate aerobic composting conditions; the addition of moisture to the compostable material; controlling the airflow by carrying out all or part of the process in a sealed building, or in-vessel, with appropriate air-handling systems; and treating all gases and odours produced during the process.
