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Introduction

Need for the guidelines

The processing of organics can deliver important environmental benefits, including the recovery and conservation of resources and a reduction in the quantity of organics going to landfills (Lechner et al. 2002). These benefits come from turning organics into useful and safe products, without causing harm to the environment. However, if commercial composting facilities are not well managed they can have serious environmental impacts.

Modern composting operations tend to process considerable quantities of organics. Consequently, the generation of unwanted by-products, particularly odours and water-soluble chemical compounds, can become greater than the capacity of natural processes to cope with them adequately. Even relatively simple tasks in composting and related organics processing – such as mulching, grinding and chopping – can have negative environmental impacts.

The occupiers of the facility are responsible for selecting and applying the best mix of techniques for site development and management for their particular location to meet the required environmental objectives.

The focus of these guidelines is on the appropriate environmental management of organics processing facilities. The document discusses the need to minimise contamination of the organic materials themselves, but only briefly mentions the use of organics and contamination issues associated with use (see Section 2).

Australia has a voluntary standard for composts, soil conditioners and mulches, Australian Standard AS4454-2003 Composts, soil conditioners and mulches. This standard adopts contamination thresholds from products derived from organic wastes, compostable organic materials and biosolids that are current federally or in individual states. The standard was developed for assessing the quality of compost produced from segregated green waste and for unrestricted use, such as domestic and residential uses.

Additionally, any material mixed with or produced with biosolids is regulated under the Environmental Guidelines: Use and Disposal of Biosolids Products (Biosolids Guidelines – EPA 1997). Whereas the Biosolids Guidelines permit the cleanest biosolids products (suitable for 'Unrestricted Use') to be used without any conditions, products containing higher concentrations of chemical contaminants (suitable for 'Restricted Use 1, 2 or 3') have stringent conditions placed on the location, method and rate of their application to land and are permitted only in non-domestic uses, such as agriculture, forestry and environmental rehabilitation.

Scope of the guidelines

These guidelines (Figure 1):

• define clearly the environmental issues that affect the management of composting and related organics processing facilities (see Section 2)
• outline the regulatory framework (see Section 3)
• identify objectives, design requirements, performance requirements and performance measurements for dealing with each issue (see Sections 4, 5 & 6).
• identify the benchmarks used for measuring and monitoring performance (see Section 6)
• outline the types of issues that should be considered when planning composting and related organics processing facilities (see Appendix A)
• identify possible environmental management techniques (see Appendix B)
• list the items to be included in an environmental management plan for composting and related organics processing facilities (see Appendix C)
• list the items to be included in a water assessment plan for composting and related organics processing facilities (see Appendix D).

Figure 1: Structure of these guidelines

Section 1: Introduction

Section 2: Overview of Environmental Issues and their Management

Section 3: Regulatory Information

Section 6: Benchmarks for Measuring and Monitoring Performance

Section 4: Guidelines for Satisfying Environmental Objectives Objective Design requirements Performance requirements Performance measurement

Section 5: Minimum Design Requirements for the Protection of Waters

Appendixes A. Facility Planning B. Environment Management Techniques C. Environmental Management Plan (EMP) D. Water Assessment Plan Glossary References and Bibliography

These guidelines cover the processing (see Table 1) of putrescible and non-putrescible organics such as:

• garden and landscaping organics
• untreated timber
• natural organic fibrous material
• processed fibrous material
• biosolids
• manures
• food organics (for example, meat, fish and fatty and oily sludges of vegetable and animal origin, including grease trap sludges)
• mixed residual waste containing organics (such as household waste).

Table 1: Types of facilities addressed by these guidelines

These guidelines address the following types of facilities: Facilities required to hold environment protection licences in Schedule 1 to the Protection of the Environment Operations Act 1997, thus including but not limited to the following types of facilities: aerobic processes (including windrow composting, static piles) anaerobic processes (including facilities that employ digestion and fermentation technologies) vermiculture shredding and/or mulching processes facilities involved in the preparation of mushroom growing substrate organics processing facilities that incorporate a biological processing stage (e.g. mechanical–biological treatment (MBT) of municipal solid waste). Facilities that utilise a biological processing stage on a larger than domestic scale but that are not required to be licensed may find useful information such as the potential environmental issues (Section 2), items to consider during planning (Appendix A) and possible environmental management techniques (Appendix B). Note: These guidelines do not provide information relating to facilities that produce fuels from organics by non-biological processes such as pyrolysis, hydrogenation or gasification.

The Environment Protection Authority (EPA) has taken a performance-based approach by setting objectives rather than prescribing particular environmental techniques that must be used. This approach intends to encourage facility operators to develop cost-effective solutions that not only achieve the right environmental outcomes but also are the most sensible and appropriate to particular operations.

Many of the environmental management techniques described in the guidelines are specific to open-air composting of organics by windrowing or static pile methodologies, because once these facilities are operating they generally require more attention to maintenance and good ongoing operating practices to mitigate environmental issues. Specific Minimum Design Requirements are provided only for mitigating the pollution of waters, because the guidelines reference other relevant publications that are available from the EPA such as the Draft Policy: Assessment and Management of Odour From Stationary Sources in NSW (EPA 2001b) for issues other than water pollution.

These guidelines also provide information on how facilities can avoid contamination in the production of compost and related organics. They do not specify standards or other requirements relating to products from composting and related organics processing facilities. For further information see the discussion in Section 2 regarding contamination of organics.

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Who should read these guidelines?

The guidelines are relevant to composting and related organics processing facilities that are required to hold environment protection licences (see Table 1). People who do composting or process organics on a larger than domestic scale but who are not required to be licensed may also find useful information in this document relating to the management of such processes.

The information provided in the guidelines aims to help:

• occupiers of existing composting and related organics processing facilities (see Table 1)
• individuals, companies, local government bodies and communities planning such facilities
• individuals or groups wishing to find out what management measures they can use to avoid or minimise the negative impacts of composting and related organics processing on local amenity, health and the environment
• suppliers or developers of individual items of equipment or entire turnkey processes for such facilities
• environmental consultants
• existing or intending users of the products of these facilities, which include composts, soil conditioners and mulches.

These guidelines can be used as a guide for the development of licence conditions for licensed facilities, but conditions may be attached to licences that vary from the guidelines owing to site-specific issues. In the event of any inconsistency between the licence conditions and the guidelines, the licence prevails as the legal requirement for the facility.

Planning a new composting facility

Figure 2 summarises the processes involved in taking a composting facility from the planning stage to the Development Application and eventually, if Development Consent is granted, to obtaining an Environment Protection Licence from the EPA. Further details can be obtained by reading the sections of these guidelines and another document (DUAP 1996) that are referred to in the figure.

Further information regarding licensing a composting facility may be obtained from your local EPA office.

Figure 2: Considerations when planning a new composting facility

Consider planning requirements and process Read the EIS Practice Guideline: Composting and Related Facilities published by the Department of Infrastructure, Plannning and Natural Resources. Contact the local council involved for their requirements.

Answer these questions about the proposed facility What are the key environmental issues associated with the facility? What is the required level of environmental performance for these issues?  What environmental management techniques are proposed to address these issues to the required level of environmental performance? How will you decide if the proposed environmental management techniques are likely to satisfy the environmental objective(s)? How can the environmental management techniques be monitored to determine whether the required level of environmental performance has been achieved? What remedial action is proposed should the monitoring show that the controls do not meet the required level of environmental performance?

 

Identify which management approaches are needed for your specific facility and organics Read: Section 3 of these guidelines for regulatory information including information about the different types of organics for which different management approaches may be used; and Sections 4, 5 & 6 and the Appendices for: Guidelines for Satisfying Environmental Objectives Minimum Design Requirements for the Protection of Waters Benchmarks for Measuring and Monitoring Performance Examples of possible Environmental Management Techniques and other information to help you in this task.

 

Prepare and submit development application to the local council accompanied by the Environmental Impact Statement or Statement of Environmental Effects as required by the council. The council will consult the EPA for General Terms of Approval which will ultimately be translated to licence conditions by the EPA.

 

Licence application If Development Consent is given by the local council you will need to obtain an Environment Protection Licence application from the EPA, complete it and submit it with the correct application fee. The EPA will use the General Terms of Approval already given to issue a licence.

 

The types and quantities of organics received and the design and siting of the processing facility determine the nature of potential pollutants that can be generated and the severity of the potential environmental risks, as well as the quality of the end-products.

Poor environmental management of composting and related organics processing facilities can result in one or more of the following environmental problems:

• air quality impacts, namely odours and particulate matter
• potential hazards, such as fire and explosions
• water and soil pollution
• loss of amenity, particularly odours, the presence of vermin in excessive numbers, excessive levels of noise from equipment (such as shredders and traffic), wind-blown litter and particulate matter from delivery trucks and earthmoving equipment
• production of contaminated organic products.