Environmental Standard: Composting (March 2016 – draft released

PAPER

1

Environmental Standard: Composting Division 3 Part V Environmental Protection Act 1986

Version: Draft released for consultation March 2016

ENVIRONMENTAL

STANDARD

Department of Environment Regulation

Environmental Standard: Composting (March 2016 – draft released for consultation) i

Produced and published by Department of Environment Regulation 168 St Georges Terrace, Perth, Western Australia March 2016

Copyright © State of Western Australia 2016

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Environmental Standard: Composting (March 2016 – draft released for consultation) ii

Contents

1. Purpose ............................................................................................................. 1

1.1 Definitions ..................................................................................................................... 2

2. Application ........................................................................................................ 4

3. Acknowledgments ............................................................................................ 5

4. Location and Siting .......................................................................................... 5

4.1 Excluded Locations....................................................................................................... 5 4.2 Siting ............................................................................................................................ 6 4.3 Risk to Groundwater ..................................................................................................... 6

4.3.1 Groundwater Value ......................................................................................... 7 4.3.2 Depth to Groundwater ..................................................................................... 7 4.3.3 Soil Type ......................................................................................................... 8 4.3.4 Composting Hardstand ................................................................................... 8 4.3.5 Risk of Leachate ........................................................................................... 10

4.4 Stormwater and Surface Water ................................................................................... 13

5. Operating Methods ......................................................................................... 13

5.1 Unacceptable Feedstock ............................................................................................ 13 5.2 Contaminants in Waste Feedstock ............................................................................. 13 5.3 Feedstock Storage Standards .................................................................................... 14 5.4 Risk of Odour .............................................................................................................. 14

5.4.1 Separation Distances .................................................................................... 14 5.4.2 Feedstock Risks and Controls for Odour ....................................................... 15

5.5 Liquid Waste ............................................................................................................... 17

6. Product specifications ................................................................................... 18

6.1 Small Retail Customers .............................................................................................. 18 6.2 Pathogen and Contaminant Limits .............................................................................. 19

7 Environmental Monitoring ............................................................................. 20

7.1 Tier 1 – Indicatory Monitoring ..................................................................................... 20 7.2 Tier 2 – Full Monitoring ............................................................................................... 21 7.3 Surface water Monitoring ............................................................................................ 21

8. Transition of Existing Facilities ..................................................................... 21

9. Bibliography .................................................................................................... 22

10. Review ............................................................................................................. 22


Environmental Standard: Composting (March 2016 – draft released for consultation) 1

1. Purpose

This document sets out the Environmental Standard (ES) for prescribed premises that carry out aerobic composting in Category 67A of Schedule 1 to the Environmental Protection Regulations 1987 (EP Regulations).

This document is intended for applicants and their consultants, the Department of Environment Regulation (DER) officers and other key stakeholders.

This document applies to all prescribed premises where the threshold for Category 67A is met.

Category 67A of Schedule 1 to the EP Regulations provides as follows:

Aerobic composting facilities that are prescribed premises under the EP Regulations (composting facilities) have the following potential risks to public health and the environment and:

(a) contamination of groundwater;

(b) contamination of surface water;

(c) contamination of soil;

(d) odour; and

(e) contamination of products.

This ES sets out the minimum standards that apply to composting facilities under the following categories of regulatory control, in order to reduce public health and environmental risks to an acceptable level.

Schedule 1 – Prescribed Premises – Part 1

Category number

Description of category Production or design capacity

67A Compost manufacturing and soil blending: premises on which organic material (excluding silage) or waste is stored pending processing, mixing, drying or composting to produce commercial quantities of compost or blended soils.

1,000 tonnes or more per year



The table below sets out the potential risks of composting and how the risks have been addressed by the requirements specified in this ES.

Requirements Specified in Environmental Standard

4.1

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4.2

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Acti

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1. Groundwater contamination (risks of impacting public drinking water supplies, public health and ecosystem health)

• • • •

2. Surface water contamination (risk of impacting ecosystem health)

• • •

3. Soil contamination (risk of impacting public health and ecosystem health)

• • •

4. Odour (risk of impacting public amenity)

• •

5. Product contamination (risk of impaction public health)

• • • •

1.1 Definitions

In this ES:

Commercial waste means all waste other than domestic waste.

Compost means an organic product that has undergone controlled predominantly aerobic and thermophilic biological transformation through the composting process to achieve pasteurisation and reduce phytotoxic compounds, and achieve a specified level of maturity1.

Composting means the process whereby organic materials are microbiologically transformed under controlled predominantly aerobic conditions to achieve pasteurisation and a specified level of maturity.

1 The specified level of maturity for compost depends on the intended classification of the product in accordance with Appendix N

of AS 4454-2012; that is, pasteurised product, compost, or mature compost



Contaminant means a substance or object in contact or mixed with a material that poses a risk of harm to human health or the environment.

Contaminated organic waste feedstock refers to organic waste feedstock which contains contaminants. See also contaminant.

Domestic waste means waste sourced from general households.

Freeboard means the distance between the maximum water surface elevations and the top of retaining banks or structures at its lowest point.

Hazardous waste means waste which by its characteristics poses a threat or risk to public health, safety or the environment (includes substances which are toxic (including mutagenic, carcinogenic and teratogenic, infectious, explosive, flammable, corrosive, oxidising and radioactive)).

Hydraulic conductivity (generally known as permeability) is a measure of a material’s capacity to transmit water.

Leachate means liquid which has drained from composting materials or products including stormwater which has accessed any potentially contaminated areas.

Natural Geological Barrier means a barrier that is proven by competent geotechnical investigations to provide a secure barrier between the groundwater, soil and substrata and the composting organics with an in-situ permeability of less than 1x10-7 metres per second (m/s) hydraulic conductivity.

Quarantine waste means material or goods of quarantine concern as determined by the Australian Quarantine and Inspection Service and which is subject to and/or identified under Commonwealth Legislation (Quarantine Act 1908) and associated regulations and proclamations.

Watercourse has the same meaning it has in the Rights in Water and Irrigation Act 1914 and means:

(a) any river, creek, stream or brook in which water flows;

(b) any collection of water (including a reservoir) into, through or out of which any thing coming within paragraph (a) flows;

(c) any place where water flows that is prescribed by local by-laws to be a watercourse,

and includes the bed and banks of any thing referred to in paragraph (a), (b) or (c). For the purposes of the definition —

(a) a flow or collection of water comes within that definition even though it is only intermittent or occasional; and

(b) a river, creek, stream or brook includes a conduit that wholly or partially diverts it from its natural course and forms part of the river, creek, stream or brook; and

(c) it is immaterial that a river, creek, stream or brook or a natural collection of water may have been artificially improved or altered.



Weeds means any plant -

(a) that is a declared pest under section 22 of the Biosecurity and Agriculture Management Act 2007; or

(b) published in a Department of Parks and Wildlife Regional Weed Rankings Summary, regardless of ranking; or

(c) not indigenous to the area concerned.

Wetland has the same meaning it has in Schedule 5 to the Environmental Protection Act 1986 and means an area of seasonally, intermittently or permanently waterlogged or inundated land, whether natural or otherwise, and includes a lake, swamp, marsh, spring, dampland, tidal flat or estuary.

Wetland of conservation value includes:

(a) a wetland included in the List of Wetlands of International Importance kept under the Ramsar Convention;

(b) a nationally important wetland as defined by the Commonwealth Government from time to time; and

(c) a wetland designated as a conservation category wetland in the geomorphic wetland maps held by the State Government from time to time and presently available from the Department of Parks and Wildlife.

Windrows means horizontally extended piles of material being composted and aerated, achieved by mechanical turning and/or the delivery of air from the base of the windrow.

2. Application

This ES will be applied as follows:

New Applications: This ES will be used to assess new applications for works approvals and licences under Division 3, Part V of the Environmental Protection Act 1986 (EP Act). Applicants must demonstrate that they meet the specified standards.

Existing Licensed Premises: Existing licences will be reviewed against this ES. This ES will be used to inform decisions on changes where required to existing licences to achieve acceptable environmental outcomes.

The Chief Executive Officer (CEO) under the EP Act reserves his/her discretion to not apply Environmental Standards:

Where standards that are more stringent than those under the ES are required to protect public health or the environment because environmental circumstances have changed, or the environment requires a higher level of protection than would be provided by the ES; or

Where applicants or licensees wish to propose deviations from the ES and the CEO is satisfied:

that such deviations achieve the same or better level of protection of; or

the CEO is satisfied the level of protection is commensurate with the risks to,

public health and the environment.



3. Acknowledgments

This ES has been developed after consideration of standards and guidance documents from other jurisdictions. In particular, DER acknowledges the contribution from the New South Wales’ Department of Environment and Conservation Environmental guidelines: Composting and related organics processing facilities (2004) and Victoria’s Environment Protection Authority Guideline: Designing, construction and operating composting facilities (2015).

The Department also acknowledges the contributions from the Composting Industry Working Group Members, the Department of Water and the Department of Agriculture and Food, for their assistance in the development of the ES.

4. Location and Siting

4.1 Excluded Locations

Performance Standard: The location for a composting facility must minimise the risk to groundwater and surface waters.

Design and Construction Standard: To protect the environmental values of surface and groundwater resources, composting facilities must not be located within:

(a) Priority 1 and Priority 2 public drinking water source areas (i.e. catchment areas, water reserves or underground water pollution control areas proclaimed under the Country Areas Water Supply Act 1947 or Metropolitan Water Supply and Sewerage Drainage Act 1909);

(b) the projected 1 in 20 (5%) annual exceedance probability (AEP) flood extent; or

(c) the portion of the 1 in 100 (1%) AEP floodplain that would detrimentally affect the existing flooding regime (i.e. raise flood levels)

Note: The term 1 in 100 AEP flood (or 1% AEP) is also referred to as the 100 year average recurrence interval flood (100 year ARI). This flood has a 1% chance of being equalled or exceeded in any year.

Existing facilities located in these areas will be risk assessed as described in Section 8.



4.2 Siting

Composting facilities must be situated at the minimum distances to environmental receptors specified in Table 1.

Table 1: Minimum distances from composting facilities to environmental receptors

Environmental receptor Minimum distance from composting facility (metres)

Maximum highest historic groundwater level

3m (vertical separation) from the base of any infrastructure to the highest historic water level

Wetland of conservation value 1,000m (down hydraulic gradient)

Watercourse, drain (surface or subsurface), wetland

500m (down hydraulic gradient)

High water mark of estuaries, which in relation to tidal waters, means ordinary high water mark at spring tides.

500m

Public drinking water source well/bore and surface water sources that supply drinking water

300m (radius)

Private potable supply well/bore 100m (down hydraulic gradient)

Where minimum distances are not met, the applicant will be required to demonstrate that sufficient controls are in place to mitigate the risk to an acceptable level.

4.3 Risk to Groundwater

Performance standard: Groundwater is not to be materially impacted by the composting activities.

Factors that determine the risk of impacting groundwater are:

(a) soil types underlying the composting facility;

(b) depth to groundwater;

(c) effectiveness of stormwater and drainage management (Section 4.4); and

(d) nature of feedstocks to be composted (Section 5).

Design standard: Composting facilities must be designed and constructed to contain the following infrastructure and systems:

(a) Composting hardstand: means all surfaces where feedstock is received and stored, processed, mixed and composted (including mixing pits for liquid feedstock), and where the final product is stored.

(b) Leachate collection system: means all infrastructure for the collection of leachate or water that may have been in contact with materials.

(c) Leachate storage infrastructure: means ponds or tanks used to store leachate.



(d) Surface water controls: means infrastructure and site works for the control of surface water within the premises.

The infrastructure and systems must meet the minimum performance, design and construction standards specified in this ES.

Note: Category F1 feedstock, as identified in Table 8, is not required to be stored on a hardstand.

The risk to groundwater from composting operations is assessed by Tables 2, 3, 4 and 5.

4.3.1 Groundwater Value

In determining groundwater value, beneficial use has been applied for Classifications G1 and G2 as shown in Table 2. Groundwater classified as G1 and G2 are also most likely to have ecosystem values. Beneficial use means a use of the environment, or of any portion thereof, which is conducive to public benefit, public amenity, public safety, public health or aesthetic enjoyment and which requires protection.

Groundwater which does not have beneficial use has been classified as G3. The beneficial use and any ecosystem values of groundwater classified as G3 will be assessed on a case-by-case basis.

Table 2: Groundwater Value

Classification Total dissolved solids (TDS)

Groundwater Value

G1 <1500 mg/L Drinking water

G2 1500 – 7000mg/L Non-potable

G3 Greater than 7000mg/L Other (eg. saline, hypersaline)

4.3.2 Depth to Groundwater

Where there are beneficial uses as determined in Table 2 (G1 and G2), further consideration of the risk to groundwater is required.

Table 3: Risk to water based on depth to groundwater

Risk category Depth to groundwater

W1 3m or less

W2 3m to 10m

W3 10m to 25m

W4 25m or greater



4.3.3 Soil Type

Where the separation between the composting facility and groundwater presents a risk, further consideration of the pathway is required. The risk category for the pathway is determined by the type of soil present as per Table 4.

Table 4: Risk to groundwater based on soil type

Risk category Soil type

S1 Fine to course gravel

S2 Fine to coarse sand, karstic limestone or fill

S3 Silt, limestone, sandstone, clayey sand, vesicular basalt or fractured rock

S4 Sandy clay, unjointed sandstone or weathered/fractured crystalline rock

S5 Clay, shale or unfractured crystalline rock

Risk rating is specified in Table 5 using the risk categories identified in Tables 3 and 4.

4.3.4 Composting Hardstand

Performance standard: composting hardstands should avoid risk of contamination of the underlying land, groundwater and surface waters.

Design and construction standards: composting hardstands must have appropriate permeability and drainage that satisfy the standards specified in Tables 6 and 7 from the risk rating identified in Table 5.

Table 5: Risk to groundwater

Groundwater risk category

W1 W2 W3 W4

So

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go

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S1 Very High Very High High High

S2 Very High High High Moderate

S3 High High High Low

S4 High High Moderate Low

S5 Moderate Moderate Low Very Low



Table 6: Drainage standard

Composting hardstand component

Design and construction standard

Drainage

Hardstand must have a minimum 1% (1:100) drainage gradient to ensure the free drainage of all leachate to the leachate collection infrastructure.

Drainage infrastructure must be include at least berm and swales (or other structures) of a suitable standard to prevent run-on and run-off of surface water, including a 1 in 20 year storm event (20 year ARI) of 24 hours duration.

Where alternatives to examples for achieving permeability are proposed, testing and expert reports may be required to demonstrate that the infrastructure will meet the permeability requirements.

Table 7: Hardstand examples for meeting risk category

Risk rating Example design and construction standards

Very High The hardstand may be constructed using one or more of the specified construction materials, which must be constructed at the relevant specified standard. In all circumstances, the hardstand must be engineered and constructed so as to be capable of accommodating the weight and movement of materials, vehicles and equipment used in the production of compost and required to operate on the hardstand, without compromising the integrity of the hardstand or altering the drainage standard.

Clay

Clay hardstand must comprise successive compaction of a minimum of two separate layers of 150 millimetres (mm) of clay once compacted. Layers must be scoured to ensure the layers are effectively bonded.

Clay liner must be at least 300mm thick in total once compacted.

Clay liner must have a hydraulic conductivity of less than 1 x 10-9 m/s.

There must be a protective layer (such as 200mm silty loam or compacted gravel) maintained over the clay liner to protect the liner from damage as a result of day-to-day activities or machinery movements.

Asphalt/concrete

Asphalt or concrete liner must be at least 100mm in thickness not including the compacted base below the liner.

All construction joints must be sealed with a suitable impervious sealant.

The asphalt/concrete liner must have a hydraulic conductivity of less than 1 x 10-9 m/s.

Other

Any other engineered hardstand that can meet the 1 x 10-9 m/s specification.



Risk rating Example design and construction standards

High The hardstand may be constructed using one or more of the specified construction materials built to achieve a hydraulic conductivity of less than 1x10-8 m/s.

very gravelly loams and clays;

loamy sand, sandy loam;

gravelly sands and loams;

sandy clay loam, sandy clay;

gravelly clay loams and clays;

silty clay loam, clay loam, sandy clay;

silt, silty loam; or

silty clay, clay.

In all circumstances, the hardstand must be engineered and constructed so as to be capable of accommodating the weight and movement of materials, vehicles and equipment used in the production of compost and required to operate on the hardstand, without comprising the integrity of the hardstand or altering the drainage standard.

Moderate The hardstand may be constructed using compacted in-situ soils. No other requirements are specified.

Low or Very Low None specified.

4.3.5 Risk of Leachate

Design and construction standards: leachate management systems must satisfy the standards specified in Tables 8 and 9.

WL1 risk classification includes water classified as W1 in Table 3 including facilities that are located between 500m to 1,000m (up hydraulic gradient) of a wetland or between 250m and 500m from a watercourse.

WL2 risk classification includes water classified as W1 in Table 3 including facilities that are located less than 500m (up hydraulic gradient) of a wetland or less than 250m from a watercourse.

Table 8: Risk of Leachate

Feedstock Risk Category

F1 F2 F3 F4

Ris

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dw

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wa

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WL1 Very Low Low Low Moderate

WL2

Very Low Low Moderate High



Table 9: Design and construction standards for risk ratings

Risk rating Design and construction standards

High Leachate collection system

Performance standard: leachate collection system must include strategically located cut-off drains, bunds, and site works for water collection that must ensure that:

(a) surface water must be diverted so that it does not come in contact with the operational areas;

(b) leachate (including contaminated surface water or stormwater) does not leave the composting facility or contaminate the underlying land, groundwater or stormwater system or surface waters;

(c) leachate is directed into the leachate storage infrastructure; and

the leachate collection system and storage infrastructure is to be

constructed as follows.

Leachate storage infrastructure

Performance standard: leachate must be stored in tanks or ponds that prevent contamination of the underlying land, groundwater and surface water.

Design and construction standards: leachate storage infrastructure must comprise of a pond or tank that satisfies the performance standard. Examples of infrastructure standards are included below.

Pond

Capacity: Ponds must have the minimum capacity determined under leachate storage capacity.

Contingency: Ponds must be designed with a contingency system to store leachate in the event that the water level exceeds the freeboard depth.

Lining: Ponds must be lined using one of the following materials, which must be constructed at the relevant specified standard:

o clay: as per the standard for composting hardstands of permeability 1.0 x 10-9 m/s hydraulic conductivity in Table 7 in section 4.3;

o asphalt/concrete: as per the standard for composting hardstands of permeability 1.0 x 10-9 m/s hydraulic conductivity in Table 7 in Section 4.3; or

High-density polyethylene, Polypropylene or Polyvinyl chloride with a minimum thickness of 1.5mm, a permeability of less than 1 x 10-9 m/s hydraulic conductivity, and capable of maintaining that permeability for the working life of the pond.

Ponds must be designed and constructed by an appropriately qualified and certified professional.



Risk rating Design and construction standards

Tank

Impermeability: Tanks must be constructed of impermeable material.

Capacity: Tanks must have the minimum capacity determined under the leachate storage capacity heading with a minimum freeboard depth of 500mm if not sealed.

Secondary containment compounds: Tanks must be enclosed by secondary containment compounds, comprising of an impermeable floor and walls/bunds (less than 1 x 10-9 m/s hydraulic conductivity) and which are resistant to stored materials.

Secondary containment compounds must have storage capacity of at least 100% storage tank or 25% of the total tankage within the containment compound, whichever is larger.

Drainage: Secondary containment compounds must drain liquids to a collection point (sump).

Bunds/walls of secondary containment: Bunds/walls penetrated by pipework must be appropriately sealed (less than 1 x 10-9 m/s hydraulic conductivity).

Bunds/walls must be constructed and placed to contain leaks from tanks and/or fittings.

Tank connection points: Tank connection points must be installed within the secondary containment compound to ensure leachate is contained in the event of pipe or connection failure or spills during transfer.

Leachate storage capacity

Ponds and tanks storing leachate must have the minimum capacity to store the total of the equivalent volume from a 1 in 20 year storm event (20 year ARI) of 24 hours duration that is collected from the operational area assuming 100% runoff coefficient. Evidence supporting the minimum capacity must be provided to the Department.

Moderate Leachate collection system

Performance standard: leachate collection system should include at least in-situ berm and swales for water collection that must ensure that:

(a) surface water must be diverted so that it does not come in contact with the operational areas; and

(b) leachate is directed into the leachate storage infrastructure.

Leachate storage infrastructure

Performance standard: leachate must be stored in tanks or ponds.

Design and construction standards: leachate storage infrastructure must comprise of a pond or tank that satisfies the performance standard. Lining and capacity requirements are not specified.

Low and Very Low None specified.



4.4 Stormwater and surface water

Performance standard: surface water and stormwater controls must be designed to minimise the generation of excessive leachate and to prevent any leachate, sediment or detritus from being discharged to the environment.

Design and construction standards: Surface water and stormwater controls must include appropriate facility design to prevent contaminated stormwater from entering feedstock, composting windrows, products or leachate ponds.

5. Operating Methods

Composting methods must be appropriate for the proposed composting feedstock. This section sets out:

(a) unacceptable feedstock that must not be accepted at composting facilities;

(b) liquid waste feedstock storage standards; and

(c) the minimum composting method that must be used based on a risk assessment of the composting feedstock.

Note: Feedstocks are a general approach to the classification of waste. Many waste streams contain small amounts of waste from various other classifications to the bulk of the waste.

5.1 Unacceptable Feedstock

The following feedstock is unacceptable for aerobic composting and must not be accepted at composting facilities:

(a) wood and wood-derived wastes impregnated with preservatives, pesticides, painted, or with any non-biodegradable layer;

(b) untreated septage and sludge (untreated waste from septic tanks, commonly referred to as sewage) including septage and sludge which has been untreated and dewatered (dewatering refers to waste which has had moisture content removed);

(c) feedstock that does not compost or has no required/beneficial properties for the composting process or final product (for example non-biodegradable plastics, glass, metals and some industrial or commercial wastes);

(d) hazardous wastes;

(e) quarantine wastes;

(f) clinical and biomedical wastes; and

(g) any other waste stream that has not been demonstrated as suitable for treatment or required by the proposed composting process.

5.2 Contaminants in Waste Feedstock

Organic waste feedstock may contain contaminants. Contaminated organic waste feedstock must not be accepted at composting facilities to be diluted by other feedstock before or as part of the composting process.

Contaminated organic waste feedstock may only be accepted where there are appropriate processes that actively treat contaminants to approved concentrations and leachability levels.



5.3 Feedstock Storage Standards

All feedstock in liquid or sludge form, if to be stored prior to use, must be stored in infrastructure that meets the standards for leachate storage infrastructure in Section 4.3.

Where more than one type of liquid waste is being accepted and temporarily stored as a feedstock, there must be separate storage in place for each waste stream, unless it can be demonstrated that their mixing will not cause unreasonable odour or adverse chemical or physical reactions.

5.4 Risk of Odour

5.4.1 Separation Distances

Composting facilities must meet the separation distance requirements from residential premises as specified in Table 10.

Table 10: Separation distances and required composting method

Description Emissions and Distance (m) from residential premises

67A outdoor uncovered Odour

2,500 for up to 35,000 tonnes per year (t/y)

1,800 for up to 20,000t/y

1,300 for up to 12,000t/y

800 for up to 5,000t/y

400 up to 2,000t/y

Above 35,000t/y then case by case

outdoor covered, turned windrows 2,200 for up to 50,000t/y

1,900 for up to 35,000t/y

1,500 for up to 20,000t/y

1,100 for up to 12,000t/y


400 up to 2,000t/y

Above 50,000t/y then case by case

outdoor covered windrows with continuous aeration

1,600 for up to 50,000t/y

1,300 for up to 35,000t/y

1,100 for up to 20,000t/y

850 for up to 12,000t/y



Above 50,000t/y then case-by-case



Description Emissions and Distance (m) from residential premises

enclosed windrows with odour control 1,000 for up to 50,000t/y

900 for up to 35,000t/y

800 for up to 20,000t/y

700 for up to 12,000t/y


400 for up to 2,000 t/y


in-vessel composting with odour control 600 for up to 50,000t/y

550 for up to 35,000t/y

500 for up to 20,000t/y

430 for up to 12,000t/y




5.4.2 Feedstock Risks and Controls for Odour

Where the separation distance requirements cannot be met the risk of odour of feedstock categories will be required to meet the composting method to control for odour.

Feedstocks (from Table 8) have been risk-rated for odour in Table 11. The composting methods for control of odour are identified in Table 12.

Table 11: Feedstock risk categories

Category Waste types Examples

F1 (Very Low Risk)

Greenwaste Grass, leaves, plants, branches, tree trunks and stumps including controlled greenwaste collections.

Untreated timber Sawdust, shavings, timber offcuts, crates, pallets, wood packaging.

Natural fibrous organics

Peat, seed hulls/husks, straw, bagasse and other natural organic fibrous organics.

Processed fibrous organics

Paper, cardboard, paper-processing sludge, non-synthetic textiles.

F2 (Low Risk)

Municipal source-separated kerbside garden waste

Grass, leaves, plants, branches, tree trunks and stumps as this source is not controlled.

Partially treated sludge and aged manure

Partially treated sludge and aged manure.




F3 (Low / Moderate Risk)

o

Treated septage and sludge and animal manures.

Includes waste from septic tanks and waste water treatment plants which has undergone treatment to a level to significantly reduce pathogens and microorganisms.

Includes biosolids (i.e. sewage sludge which has been treated e.g. by liming or anaerobic digestion and then dewatered).

Solid animal manures and animal bedding organics.

Other natural or processed vegetable organics

Vegetables, fruits and seeds and processing wastes, solid winery, brewery and distillery wastes.

Mixed source separated kerbside garden waste/food waste

Grass, leaves, plants, branches, tree trunks and stumps, vegetables, fruit and other food scraps.

F4 (Moderate / High Risk)

Meat, fish and fatty foods

Animal mortalities, parts of carcasses, bone, fish and fatty processing or food and abattoir waste.

Municipal putrescible waste from domestic, commercial or industrial premises

Food, kitchen and other putrescible wastes, disposed of into municipal waste collection systems.



Table 12: Required composting method based on feedstock risk category for odour

Feedstock categories

Required composting method

Open environment Controlled environment or additional controls

F1 Yes Yes

F2 Yes Yes

F3 No Yes

F4 No No

Open environment: where feedstock is processed outdoors, via open air composting methods where the process can be kept aerated through regular turning of the piles or forced aeration.

Controlled environment or additional controls: where feedstock is at a moderate to high risk of odorous emissions, it may be processed in enclosed or covered systems that provide a level of engineered control through the enclosure (that is, through covering of windrows with forced aeration, or enclosure of windrows within sheds), as well as offering a limited level of control over the odour emissions or other controls are in place to manage the risk of odour.

5.5 Liquid Waste

Liquid waste feedstocks as specified in Table 13 may only be accepted as a feedstock where the following can be satisfied:

(a) the liquid waste is of benefit, other than solely providing moisture content, to the biological process contributing to making the compost; and

(b) the quantity ratio of liquid waste to other solid and liquid feedstocks can be specified as a regulatory control.

Table 13: Liquid Waste Feedstock


Liquid waste Liquid organic wastes, including sludges

Liquid food waste and liquid food processing wastes (including sludges), liquid animal wastes (blood and manures) and paunch (sludge), raw liquid winery waste, grease interceptor trap waste (kitchen and restaurant)



6. Product Specifications

All materials produced from composting facilities are considered as materials.

Material means materials produced from composting.

Product refers to Material that meets the Product Standards.

Product Standards means the requirements of Australian Standard (AS) 4454: 2012 Composts, Soil Conditioners and Mulches (AS 4454: 2012) for the following categories:

(a) Pasteurised product: An organic product that is relatively immature and lacking biological stability that has undergone the pasteurisation processes and parameters as stated in AS 4454: 2012.

(b) Compost: An organic product that has undergone controlled aerobic and thermophilic biological transformation through the composting process to achieve pasteurisation and reduce phytotoxic compounds, and has achieved a specified level of maturity for compost (as stated in AS 4454: 2012 Appendix N).

(c) Mature compost: An organic product that has undergone controlled aerobic and thermophilic biological transformation through the composting process to achieve pasteurisation and exhibits lower levels of phytotoxicity and a higher degree of biological stability (as stated in AS 4454: 2012 Appendix N).

6.1 Small Retail Customers

Material that is intended to be, or is available to be, sold to small retail customers must meet the Product Standards.

Small retail customers refer to retail (non-commercial) customers who purchase less than five cubic metres (m3) of material in a single transaction.

Product includes material which is blended with additional matter (not with wastes of any type) for a specific end market involving small retail customers. Material must meet the Product Standards before blending occurs.



6.2 Pathogen and Contaminant Limits

Products must meet the pathogen, chemical and physical contaminant limits set out in Tables 14, 15 and 16.

Table 14: Pathogen limits

Pathogen Limit

Coliphages <10 plaque-forming unit per 10 grams total (dry weight)

E. coli <100 counts per gram (dry weight)

Strongyloides and hookworm (viable ova)

<1 per 50 gram (dry weight)

Salmonella spp. Absent in 50 grams of final product (dry weight)

Table 15: Destruction of weeds

Contaminant Limit

Destruction of weeds (viable plant materials and propagules)

Nil (germination) after 21 days incubation

Table 16: Chemical and physical contaminant limits

Contaminant Limit

Dry weight basis milligram per kilogram (mg/kg)

Contaminant Limit

Dry weight basis milligram per kilogram (mg/kg)

Arsenic 20 Zinc 300

Cadmium 1 DDT/DDD/DDE 0.5

Boron 100 Aldrin 0.02

Chromium 100 Dieldrin 0.02

Copper 150 Chlordane 0.02

Lead 150 Heptachlor 0.02

Mercury 1 HCB 0.02

Nickel 60 Lindane 0.02

Selenium 5 BHC 0.02

Glass, metal and rigid plastics

≤0.5 % weight per weight

Plastics – light and flexible or film

≤0.05 % weight per weight

Polychlorinated Biphenyls (PCBs)

<0.2



7 Environmental Monitoring

Outcome: the composting facility is not to change the material background levels in the existing environment.

Composting facilities must have a program in place for the regular monitoring of groundwater bores for major water quality indicators to detect any change in water quality over time. New facilities will also be required to undertake background monitoring to establish baseline conditions prior to the commencement of composting operations.

Composting facilities must have a minimum of three groundwater monitoring bores installed on the premises for monitoring of groundwater quality and detection of potential leachate contamination or leakages in the liners or other infrastructure, with at least one ‘control’ bore located up-hydrogeological gradient of the activity area to establish background quality and at least two ‘impact’ bores down-hydrogeological gradient. Additional boreholes or monitoring may be required where liquid waste is applied or within P3 public drinking water source areas. The number of additional boreholes will be determined by the Department based on the scale of the operation and the sensitivity of the receiving environment.

Unless special circumstances exist, all surface water and Tier 2 water quality analysis is to be undertaken by a laboratory accredited by the National Association of Testing Authorities for the specified parameters.

7.1 Tier 1 – Indicatory Monitoring

All composting facilities will be required to undertake Tier 1 indicatory monitoring where groundwater is present at the site (i.e. groundwater is less 25 metres below ground level). A basic sweep of monitoring parameters is to be monitored as specified in Table 17.

Table 17: Tier 1 minimum environmental groundwater monitoring requirements

Monitoring location

Parameter Units Frequency

Groundwater monitoring bores

Standing water level mbgl Quarterly for a period of one year prior to operation.

Quarterly during first year of operation and 6 monthly during operation.

pH pH units

Electrical conductivity μS / cm

Nutrients: total nitrogen and total phosphorus

mg/L

REDOX potential mV

Temperature °C

Note: In-field measurements are acceptable for Tier 1 monitoring.



7.2 Tier 2 – Full Monitoring

Tier 2 monitoring is triggered where a 10% change in background water quality is detected.

Where Tier 2 monitoring is required, a hydrological engineer or competent person must determine the position, depth and location of monitoring bores.

Monitoring parameters will be determined by the Department for individual licences as required.

7.3 Surface Water Monitoring

In some circumstances surface waters may be an expression of, or influenced by, groundwater input. Where surface waters are within the premises boundary of the composting facilities, these waters must be regularly monitored as per the specified parameters in Table 18.

Table 18: Minimum surface water environmental monitoring requirements

Monitoring location

Parameter Units Frequency

Surface water (where a naturally occurring water body is present within the premises boundary); minimum 1 upstream monitoring location and 1 downstream monitoring location.

pH pH units Six-monthly for a period of one year prior to operation.

Six-monthly during operation.

Nutrients: total nitrogen, ammonia nitrogen, nitrate + nitrite nitrogen, total phosphorus

mg/L

Biochemical oxygen demand mg/L

Total dissolved solids μS/cm

Major ions (sodium, potassium, calcium, magnesium, chloride, sulphate, bicarbonate)

mg/L

Heavy metals (aluminium, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, vanadium and zinc)

mg/L

8. Transition of Existing Facilities

Existing facilities will be required to undertake environmental performance against the ES. If the proponent is able to demonstrate that the risk to the environment is acceptable for its existing facility, then DER has no need to require additional controls. Where additional controls are required, these will be included as licence conditions specifying improvements or changes required and timeframes for achieving these improvements or changes required.



9. Bibliography

Australian Standard AS 4454-2012 – Composts, soil conditioners and mulches

Compos Guideline, Environmental Protection Authority South Australia, 2013

Designing, constructing and operating composting facilities (publication 1588), Environmental Protection Authority Victoria, 2015

Environmental Guidelines: Composting and Related Organics Processing Facilities, Department of Environment and Conservation (NSW), 2004

Guidance for the Assessment of Environmental Factors: Separation Distances between Industrial and Sensitive Land Uses, Environmental Protection Authority of Western Australia, 2005

Guideline - Open windrow composting under Environmentally Relevant Activity 53 Compost and soil conditioner manufacturing, Department of Environment and Heritage Protection

State Planning Policy 2.2 Gnangara Groundwater Protection, Western Australian Planning Commission, 2005

State Planning Policy 2.3 Jandakot Groundwater Protection Policy, Western Australian Planning Commission, 2014

Water Quality Protection Note 25: Land use compatibility in Public Drinking Water Source Areas, 2004

Water Quality Protection Note 90 Organic material – Storage and Recycling, Department of Water, 2011

Western Australian guidelines for biosolids management, Department of Environment and Conservation, 2012

10. Review

This environmental standard is to be reviewed no later than as soon as practicable following the fifth year of its commencement.

Documents

Environmental Standard: Composting (March 2016 – draft released