Health and safety, emissions and emissions control issues for composting of mixed and separately collected MSW fractions have been extensively reviewed (e.g. CIWM 2002, Deportes et al. 1995, Efstathios and Stentiford 2004, Epstein 1996, Forster et al. 2001, Gillett 1992, Newport 1990).
In 2004 the Composting Association produced a Guide for Site Managers on Health and Safety at Composting Sites, which provides comprehensive guidance. Also in 2004 Defra released a detailed Review of Environmental and Health Effects of Waste Management: Municipal Solid Waste and Similar Wastes. This describes in detail the possible health effects that might be attributable to composting operations. In 2001 the Environment Agency released Technical Guidance on Composting Operations, which covered potential environmental impacts of composting and the regulation of the process. Operational risks of composting operations are also discussed on: http://www.hse.gov.uk/waste/composting.htm.
There are a range of operations encompassed in composting mechanically segregated fractions of MSW:
· waste collection
· pre-processing
· composting
· refining
· distribution
· use.
Composting and its ancillary operations should only take place with the advice of recognised health and safety officers, and must be compliance with appropriate health and safety law and regulations. This document does not provide advice that can be used as definitive in the development of health and safety policies and guidelines. Applicable regulations and legislation includes (not an exhaustive list):
· Health and Safety at Work Act 1974
· The Management of Health and Safety at Work Regulations 1999
· Environment Agency Position on Composting and Health Effects, August 2001
· Control of Substances Hazardous to Health Regulations 2002 (COSHH)
· Noise at Work regulations
· Animal By-Product Regulations 2003
· Reporting of Injuries Diseases and Dangerous Occurrences Regulations 1995 (RIDDOR)
See Composting Association 2004 for further information.
This chapter aims to point out the key issues connected with health and safety, emissions and emissions control, and to provide case studies, examples and review references related to the composting of mechanically segregated MSW. The following topics are covered:
· leachate
· odour / volatile organic compounds (vocs)
· dust
· bioaerosols and other health risks
· vermin / birds / insects
· fire risks.
Other issues include noise, litter which may be blown off site and hazards presented by amendments and chemicals used (such as pesticides), machinery and transport, which are not covered by this review. Further information is available from: Composting Association 2004, Environment Agency 2001, Mays et al. 1973, Williams 1999). Note that litter can present a direct hazard to foraging animals (Mays et al. 1973).
See also the Critical Review Sections: Product Quality and Environmental Impacts, in particular: Product Quality and Environmental Impacts - Microbial and Pathogen Issues.
From a sustainability point of view one should consider the overall balance of inputs and outputs around the composting operation. Inputs include energy, materials, water, for example. Outputs include emissions such as carbon dioxide, nitrogen compounds, potentially hazardous substances etc. See the Critical Review Section, Operational and Strategic Issues.