Re-use Potential of Agri-Industry Wastes...iii Foreword Wastes from agricultural industries have...

Re-use Potential of Agri-Industry Wastes In the Melbourne / Metropolitan Region A report for the Rural Industries Research and Development Corporation Barry Meehan, Jay Maheswaran and Kim Phung November 2001 RIRDC Publication No 01/144 RIRDC Project No RMI-10A

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© 2000 Rural Industries Research and Development Corporation. All rights reserved. ISBN 0 642 58364 1 ISSN 1440-6845 Reuse Potentials of Agri-Industry Waste in the Melbourne/Metropolitan Region Publication No. 01/144 Project No. RMI-10A The views expressed and the conclusions reached in this publication are those of the author and not necessarily those of persons consulted. RIRDC shall not be responsible in any way whatsoever to any person who relies in whole or in part on the contents of this report. This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquires concerning reproduction, contact the Publications Manager on phone 02 6272 3186. Researcher Contact Details Associate Professor Barry Meehan Principal Investigator Department of Applied Chemistry RMIT University 124 La Trobe St MELBOURNE 3000 Phone: 03 9925 2119 Fax: 03 9639 1321 Email: [email protected]

Dr Jay Maheswaran Principal Investigator State Chemistry Laboratory Dept. Natural Resources and Environment Sneydes Road WERRIBEE 3030 Phone: 03 9742 8726 Fax: 03 9742 8700 Email: [email protected]

RIRDC Contact Details Rural Industries Research and Development Corporation Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6272 4539 Fax: 02 6272 5877 E-mail: [email protected]. Website: http://www.rirdc.gov.au Published in November 20001 Printed on environmentally friendly paper by Canprint

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Foreword Wastes from agricultural industries have great potential for re-use as sources of water, organic matter, nutrients, mulches or soil conditioning agents (Rechcigl and Herbert 1997). Currently, there is little compiled information on agri-industry wastes produced in Victoria. Furthermore, wastes from such industries are often by default deemed as prescribed wastes making land disposal an expensive option. Surveying and characterising these wastes is essential before any assessment can be made of their re-use potential. If the waste streams are non-toxic and free of contamination, they can be effectively re-used by careful selection and suitable pre-treatment. By combining different waste streams, high nutrient value composted materials with consistent physical and chemical characteristics could be produced and tailored to suit various crop and soil requirements. The principal aim of this investigation was to identify, characterise and establish whether these waste streams had potential for re-use. A number of waste streams with high reuse potential were identified and information on their volume and composition was collated. On the basis of this survey, a number of waste streams were selected for further investigation. Composting was found to be an effective method for the remediation of cut flower waste contaminated with a number of common pesticides. The resulting composted product was subsequently shown to be an effective bulking agent for potting mixes in ornamental flower production. In a further study, composting was investigated as a means of diverting large quantities of potato scrap and peelings from landfill disposal. The strategy adopted in both of these studies was to stream the particular waste into a domestic green-waste composting operation. This project was funded from RIRDC Core Funds, which are provided by the Federal Government. This report, a new addition to RIRDC’s diverse range of over 700 research publications, forms part of our Resilient Agriculture Systems R&D program, which aims to foster agri-industry systems that have sufficient diversity, flexibility and robustness to be resilient and respond to challenges and opportunities. Most of our publications are available for viewing, downloading or purchasing online through our website: downloads at www.rirdc.gov.au/reports/Index.htm purchases at www.rirdc.gov.au/eshop

Peter Core Managing Director Rural Industries Research and Development Corporation

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Acknowledgments The project team would like to take the opportunity to thank all of the companies that participated in the survey and in particular the companies and organisations listed below that provided statistical and important anecdotal information and samples of their waste streams for the study. AusTanners Pty Ltd

City of Melbourne

ConAgra Wool Pty Ltd

EcoRecycle Victoria

F&I Baguley Flower & Plant Growers

Flower Industry Association Australia Inc

Grandiflora Nurseries

Heinz-Watties Australia

Institute of Horticulture Development

Kraft Foods Ltd

Melbourne Market Authority

Melbourne Wholesale Fishmarket

Mornington Peninsula Wine Growers Association

Mulch Master

Port Phillip Wool Processing Pty Ltd

Pridhams (Organic Recyclers)

RMIT University

Rutherglen Agriculture Research Institute Agriculture Victoria

SnackBrands Australia

State Chemistry Laboratory Agriculture Victoria

The Victorian Environment Protection Authority

Universal Greening Morwell

VanWyk’s Flowers

Victoria Wool Processors Pty Ltd

Victorian Farmers Federation, Chicken Meat Group

Victorian Fishing Industry Federation

Victorian Hair and Hide Processors

Yarra Valley Wine Growers Association

Special thanks to the individuals and organisations below , without whom the case studies described in the second section of this report research would have been impossible. F&I Baguley Flower & Plant Growers

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Frank Baguley, Shane Baguley, Graeme Guy SnackBrands Australia Tim Fleay

MulchMaster

Garry (Bluey) Higgs and Michael Strickland Staff of State Chemistry Victoria Justine Cody, Jo Stokes, John Caudaro, Fawzia Tawfik and Siegfriend Engleitner Staff of Institute of Horticulture Development Vanessa Hood Staff of RMIT Dr. Jeff Hughes, Sue Holden, Fiona Baxter, Karl Lang and Howard Anderson Students Anne-Marie Dziedzic, Nathan Scholes Rural Industries Research Development Corporation The research team would like to gratefully acknowledge the financial assistance provided by the Rural Industries Research and Development Corporation to undertake this research program. We believe that this project is an important step in the development of resource reuse and recovery strategies in agri-industries in urban and regional centres in Victoria.

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Contents FOREWORD .....................................................................................................................III

ACKNOWLEDGMENTS......................................................................................................... IV

LIST OF TABLES................................................................................................................. VIII

LIST OF FIGURES.................................................................................................................. X

EXECUTIVE SUMMARY........................................................................................................ XI

1. INTRODUCTION.............................................................................................................1

1.1 Survey of Putrescible Wastes in Melbourne/Metropolitan Area ......................................2

1.2 Prescribed Waste Survey Findings.................................................................................3

1.3 Wool Scour Wastes ........................................................................................................4

1.4 Tannery Wastes..............................................................................................................9

1.5 Food Processing Wastes ..............................................................................................14

1.6 Poultry Processing ........................................................................................................18

1.7 Miscellaneous waste streams .......................................................................................21

1.8 Overall findings of the survey........................................................................................25

2. WASTE REMEDIATION STUDIES...............................................................................29

2.1 Composting ...................................................................................................................29

2.2 Composting Trials .........................................................................................................29

2.3 Composting Trial 1- Remediation of Cut flower wastes ...............................................29

2.4 Composting Trial 2 - Remediation of Cut flower wastes ...............................................37

2.5 Composting Trial 3 - Potato Scraps Wastes .................................................................43

3. OUTPUTS ....................................................................................................................46

3.1 Major Findings of Survey of Putrescible Wastes in Victoria..........................................46

3.2 Major Findings of waste Remediation Trials .................................................................48

4. COMMUNICATIONS AND RECOMMENDATIONS......................................................50

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5. REFERENCES..............................................................................................................51

6. APPENDICES...............................................................................................................52

APPENDIX 1 Chemical Analysis of Waste Material 1999.....................................................52

APPENDIX 2 Chemical Analysis of Potato Waste ................................................................60

APPENDIX 3 Composting Trial 1:Remediation of Cut Flower Waste ...................................62

APPENDIX 4 Composting Trial 2: Remediation of Cut Flower Waste ..................................66

APPENDIX 5 Composting Trial 3: Remediation of Potato Solid Waste ................................73

APPENDIX 6 Paper presented at Contaminated Waste Industry, Future Directions Conference......................................................................................................76

7. GLOSSARY ..................................................................................................................86

8. PHOTOGRAPHS ..........................................................................................................88

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List of Tables

Table 1 Collated Volumes of selected waste streams in the Melbourne – Metropolitan region from January to December 1997 (source Victorian EPA) ......................4

Table 2 Waste types generated in the wool scouring process.......................................5

Table 4 Analytical results for wool scour sludge and wool fibre/dirt wastes from three companies.........................................................................................................6

Table 5 Soil properties and broccoli harvest results after land application of composted wool scour waste...............................................................................................7

Table 6. Pasture yield under fertiliser and suint treatments as sources of potassium ....8

Table 7. Potassium uptake in pastures under fertiliser and suint treatments as sources of potassium......................................................................................................8

Table 8. Yield and potassium uptake in potatoes treated with different forms of potassium..........................................................................................................8

Table 9 Waste types generated in the leather tanning process ...................................11

Table 10 Tannery wastes generated per week at two Melbourne operations................11

Table 11 Analytical results for tannery wastes from two companies..............................11

Table 12 Concentration of plant nutrients and heavy metals in waste hair....................12

Table 13. Soil and lettuce characteristics as affected by application of waste hair as an alternative source of nitrogen and moisture retaining agent. ..........................13

Table 14 Potato waste produced per week at the Snack Brands operation in Victoria..17

Table 15 Characteristics of potato scraps and peelings 2000 .......................................18

Table 16 Analysis of %Moisture, pH, EC, C/N and Total N for waste from Potato Waste. 18

Table 17 Typical wastes generated in cut flower operations .........................................21

Table 18 Analysis of typical grape marc sample from a Victorian vineyard ...................23

Table 19 Miscellaneous waste streams identified in the Melbourne region generated in the food production industry (each example is information obtained from one facility only) .....................................................................................................24

Table 20 Samples of food wastes analysed for nutritive value and contaminants from two food-manufacturing companies ................................................................25

Table 21 Analytical results for oats husks wastes from cereal food production.............25

Table 22 List of Chemical additives used by Cut flower companies 1998 .....................30

Table 23 Preliminary analysis of pesticides being used at time of sampling in cut flower waste from two different flower farms 1998 ....................................................31

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Table 24 Windrow Dimensions for each Treatment. ......................................................31

Table 25 Description of Applied Treatments ..................................................................32

Table 26 Chemical Characteristics of composted products as compared to AS4454 –1999. ...............................................................................................................35

Table 27 Pesticide Analysis Results for composted samples of the Control, 20% Treatment and 50% Treatment .......................................................................36

Table 28 Treatments used in Pot Trial ...........................................................................37

Table 29 Pesticide residues analysed in cut flower waste April 2000............................38

Table 30 Windrow dimensions for each treatment.........................................................39

Table 31 Chemical Characteristics of composted products compared to as 4454 –1999 ................................................................................................42

Table 32 Pesticides analysed in 50%composted cut flower waste June 2000 ..............42

Table 33 Characteristics of potato scraps and peelings 2000 .......................................44

Table 34 Analysis of %Moisture, pH, EC, C/N and Total N of waste from Potato Waste ..................................................................................................44

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List of Figures Figure 2 Total tannery waste volume (sludges and solids) transported to landfill in

Melbourne in 1997 versus month....................................................................10

Figure 3. Total seafood volume (solids) transported to landfill in Melbourne in 1997 versus month...................................................................................................15

Figure 4. Total meat processing (solids) transported to landfill in Melbourne in 1997 versus month...................................................................................................16

Figure 5. Total dairy waste (solids) transported to landfill in Melbourne in 1997 versus month ..............................................................................................................16

Figure 6. Total potato waste (potato scrap and sludges) transported to landfill in 1997 versus month...................................................................................................17

Figure 7. Total poultry litter transported to landfill in 1997 versus month.......................19

Figure 8. Total liquid poultry waste transported to landfill in 1997 versus month...........19

Figure 9 Comparison between Average Core Temperature of Control & 10% Treatment........................................................................................................33

Figure 10 Comparison between Average Core Temperature of Control & 20% Treatment................................................................................................33

Figure 11 Comparison between Average Core Temperature of Control & 50% Treatment ...............................................................................34

Figure 12 Comparison between Average Core Temperature of Control replications......40

Figure 13 Comparison between Average Core Temperature of 50% Treatment replications ......................................................................................................40

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Executive Summary Major Objective of the Project RMIT University and Agriculture Victoria have conducted a collaborative research program to investigate the re-use potential of agri-industry wastes being produced in the Melbourne / Metropolitan region. The research project was funded by RIRDC Core Funds and was designed to: survey and classify solid waste streams at a number of agri-industry facilities in the

Melbourne/Metropolitan region according to nature, volume and potential for re-use chemically and physically characterise a selected range of raw wastes to determine their suitability

as agricultural and other resources, carry out chemical and biological screening through laboratory analysis, of selected wastes to

assess their suitability for development as value added end products.

carry out screening through pot trials, of selected wastes to assess their suitability for development as value added end products.

investigate options necessary to convert selected wastes into resources

communicate benefits of waste reduction and re-use to agri-industries.

extend results obtained from the study to waste producers, end produce users, extension officers

and researchers.

Key Findings The survey component of the study has shown that available EPA data on putrescible waste streams in the Melbourne – Metropolitan area only reveals a small fraction of the potentially reusable putrescible wastes that are disposed of in landfills. Many waste streams were identified and characterised and found to be suited to treatment technologies such as composting. The Melbourne region generates huge volumes of green wastes from domestic and municipal council sources (approximately 0.5 million tonnes per year) and these are composted under Australian Standards at several facilities around Melbourne. These operations could be effectively utilised to treat clean putrescible wastes by incorporation into the composting process (as demonstrated in two studies carried out by the investigators in this project). In the Melbourne and Metropolitan region, there are several high value agricultural enterprises (eg. Vineyards, Vegetable production, Turf grass industry, Cut flower industry, Ornamental nursery industry, etc) which can potentially utilise these wastes in their direct form or after pre-treatment for their nutrient or soil ameliorant value. The major findings of the survey are listed below. The specific outcomes for each industry investigated are indicated. Findings in some waste remediation trials and also land application trials are also summarised. Wool scouring large volumes of wool scour sludges relatively free of contamination are disposed of in landfills in the Melbourne region each year particularly in the latter part of the year

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the majority of wool scour sludges that are generated are not reused in any way (land disposal of untreated sludge would appear to be only a short term option and could pose environmental problems such as surface water pollution, odour, groundwater contamination)

all wool scour companies surveyed acknowledge that solid and liquid wastes from these

operations pose significant environmental problems as well as the burden of the high disposal costs and that alternatives to landfilling and disposal to sewer must be found.

wool scour sludges can be effectively composted by blending with other agents such as wood chip

waste and animal hair to produce a product which has high value as a soil ameliorant and fertiliser thus completely eliminating landfill disposal of this waste stream

wool scour effluents can be reused as a potassic fertiliser or as a water source in wool scour sludge

or other composting operations technologies are available to greatly reduce the pollution load of wool scour effluents with

subsequent reduction of disposal costs and environmental impact Tanneries large volumes of tannery sludges and partly hydrolysed hair wastes are disposed of in landfills in

the Melbourne region each year particularly in the latter part of the year waste streams from leather tanning operations include, large quantities of effluent (approximately

3000L per 100kg of hide treated), flesh cut from hides, fleshy scrapings, fatty tissue, hair, sludges from various stages of the process and chromium treated leather trimmings

all tannery sludges that are generated are not reused in any way

all tanneries surveyed acknowledge that solid and liquid wastes from these operations pose

significant environmental and disposal costs and that alternatives to landfilling must be found tannery sludges from the latter stages of the tanning process (designated Tannery Sludge and

Tannery Sludge Cr) were found to be particularly high in chromium and consequently could not be used directly in agricultural application

sludges from various stages of the process are often cross-contaminated and mixed together rather

than separating recyclable sludge from heavily contaminated sludge the fatty sludges were relatively free of contamination and should be investigated for reuse; this

waste stream has potential for bioremediation tannery hair was found to be high in nitrogen and the chromium levels detected in the sample were

well below the ARMCANZ guidelines and consequently this material has great potential for reuse as a nitrogen source

waste hair from tannery operations can be used as an alternative source of nitrogen and a moisture

retaining mulch in vegetable production and also has demonstrated potential as a nitrogen source in blended waste composts.

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Food Processing the EPA data obtained is clearly not comprehensive for the food processing and related industries

and only serves as a crude guide to putrescible waste streams in the Melbourne –Metropolitan region

there are significant potentially recyclable waste streams (not recorded in the EPA data supplied)

generated in the food processing industry in the Melbourne region which are generally free of contamination and would be suited to composting by blending with other waste streams

food processing is a very large industry in the Melbourne Metropolitan area which produces a

wide range of solid and liquid wastes which are currently transferred to landfill potato wastes can be remediated effectively and inexpensively by windrow composting with

green-waste the high moisture content of the potato waste has a slight cooling effect on the windrow but does

not affect the composting process when added at a rate of 20% by volume higher rates of potato waste could be remediated by this technique but further trials would need to

be established to optimise the waste loading chicken litter is a huge waste stream which is almost completely recycled into the horticultural

production industry there is an urgent need to develop guidelines for the composting and appropriate application rates

for the land application of poultry litter in horticultural activities there is an urgent need to develop alternative strategies to landfilling of bird carcasses from the

poultry industry in the seafood processing industry, most of the solid wastes produced are recycled as pet food and

fertiliser and relatively small amounts (mainly shark skins, offal and shell) are transferred to landfills

most of the solid wastes produced in meat processing are recycled for pet food, fertilisers and

rendered to extract useful components and relatively small amounts are transferred to landfills abattoirs produce large volumes of liquid effluent which is generally disposed of by application to

land abattoir effluents should be investigated as a possible water source in composting operations

dairy food manufacture produces large quantities of cheese whey and sludges which have high

potential for reuse due to high nutritive value

potato wastes produced in the potato chipping industry consist of peelings, whole potatoes, potato pieces, dirt and sludges

Vermiculture should be investigated as a suitable option for disposal of some wastes streams in

food processing

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oats husks from cereal food production has a high C: N ratio and some nutritive value (P 1000 mg/kg) and could be blended with moist higher nitrogen source wastes (sludges) in composting in view of its light texture and high moisture affinity.

Cut Flower production cut flower wastes can effectively be combined into a green-waste composting operation without

any significant effect on the composting process as indicated by the results of average core temperatures and physical measurements

residual pesticides in the cut flower waste were reduced to undetectable levels during the

composting process and the resultant compost was suitable for land application Wine Production grape marc is a large and potentially recyclable waste stream generated in wine production

grape marc has high nutritive value and could be converted into a soil conditioner / fertiliser by

composting with other waste streams grape marc has the potential to be used to extract grape seed oil

An additional result from the project was the development of a number of undergraduate and post-graduate research investigations in the Applied Science and Engineering Faculties at RMIT University. These projects are funded by postgraduate research scholarships, University and Agriculture Victoria Resources.

These include:

final year Environmental Engineering Design projects in waste management strategies for Wool Combing and Cut flower production companies. (Projects supervised by Associate Professor Barry Meehan in conjunction with industry representatives)

an Honours project to investigate the bio-remediation of contaminated Cut flower waste using windrow composting. (Project supervised by Associate Professor Barry Meehan)

a doctoral research project on the utilisation of regional waste streams in viticulture. (Project supervised by Associate Professor Barry Meehan).

Communications and Recommendations Results of the present study have previously been communicated to RIRDC in progress reports

and have also been communicated at several waste management conferences and work shops ( see below) It is recommended that further surveying needs to be carried out in regional Victoria as well as

Metropolitan Melbourne in order to identify significant waste streams containing reusable organics that are not recorded as prescribed wastes and are disposed of in domestic landfills. These materials could then be investigated for potential recovery and reuse in agricultural and horticultural operations. Various Metropolitan and Rural industries should fully explore the opportunities to convert high cost wastes into value added environmentally friendly by-products.

It is recommended that various Institutes of Agriculture Victoria should undertake applied Research and Development to characterise modify / manage and utilise agri-industry wastes produced in their respective regions with a view to facilitating regional waste management strategies for post-farmgate wastes ( this initiative is currently being developed by the recently

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formed Resource Reuse and Recycling for Primary Industries Group in Agriculture Victoria in conjunction with RMIT University)

Care must be taken to control any adverse effects from waste applications such as induced salinity and sodicity, nutrient imbalances, high BOD, contamination from organic residues and heavy metals which underlines the importance of thorough characterisation of waste streams before they are developed into value added products for land application.

Benefits for development of reuse and recycling strategies in post-farmgate wastes accrue to industry by reducing waste disposal costs and establishing an environmentally friendly image important for marketing products locally and overseas.

Research Papers and Communications 1. Ken Peverill, Jay Maheswaran, Barry Meehan, Kim Phung (2000). Workshop on Remediation of

Agri-Industry Solid Waste using Composting, Maine University August 2000, USA (oral presentation)

2. Ken Peverill, Jay Maheswaran, Barry Meehan, Kim Phung (2000) , Conversion Opportunities for

Agri-Industry Wastes, Compost 2000 Down Under, November 2000, Melbourne ( composting workshop presentation)

3. Ken Peverill, Jay Maheswaran, Barry Meehan, Kim Phung and Anne-Marie Dziedzic (2000).

Conversion of Green-waste from Cut flower Production into A Value-added Soil Ameliorant, Proceedings of Towards Better Management of Wastes and Contaminated Sites in the Australasia-Pacific Region Conference, May 2000, Adelaide (oral presentation and abstract)

4. Ken Peverill, Jay Maheswaran, Barry Meehan, Kim Phung and Anne-Marie Dziedzic (2000).

Conversion Opportunities for Agri-Industry Wastes, Proceedings of Towards Better Management of Wastes and Contaminated Sites in the Australasia-Pacific Region Conference, May 2000, Adelaide (poster presentation)

5. Ken Peverill, Jay Maheswaran, Justine Cody, Barry Meehan, Fiona Baxter, Kim Phung and Anne-

Marie Dziedzic (1999). Conversion Opportunities for Agri-Industry Wastes, Proceedings of Contaminated Wastes Industry Future Directions Conference, November 1999, Melbourne (oral presentation and full paper)

6. Barry Meehan (1999) Cooperative Research in Agri-industry Wastes at RMIT University,

Workshop: Organic Soil Ameliorants, Agricultural Victoria, Bendigo, July 1999, Melbourne (oral and abstract)

7. Nathan Scholes (1999). Wool Scouring: The Process, its Waste and Potential Treatment

Technologies, Environmental Engineering Design Project, November 1999, RMIT University 8. Anne-Marie Dziedzic (1999). Honours Project Conducted in Conjunction with RIRDC Project:

Conversion of Green-waste from Cut flower Production into A Value-added Soil Ameliorant, November 1999, RMIT University

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1. Introduction The disposal of wastes to landfill is a significant cost to manufacturing industries resulting in increased production costs and reduced profitability. Disposal of solid wastes to landfill can have serious ecological implications as well as loss of potentially valuable resources. Further, disposal of liquid waste streams to waterways in both rural and metropolitan regions is quite unacceptable and strategies for reuse of these resources need to be developed. In 1998 the Environment Protection Authority (EPA) unveiled a new Industrial Waste Strategy which is specifically targeted at solid and liquid wastes generated by Victorian industries (EPA Industrial Waste Strategy 1998). One of the key strategic objectives announced in the strategy is to maximise the economic value of resources during their life cycle through re-use, recycling and energy recovery in preference to disposal. In order to achieve this goal, it is essential that options for re-use of waste streams be explored. Wastes from agricultural industries have great potential for re-use as sources of water, organic matter, nutrients, mulches or soil conditioning agents (Rechcigl and Herbert 1997). Australian agricultural soils are generally low in nutrient status and in organic matter, which can make them highly susceptible to nutrient mining, structural decline and erosion. Re-use of waste water in the dry Australian climate is also essential not only to conserve this limited resource but also to protect ground and surface water reserves from contamination. There is therefore a prime facie case for the investigation of suitable agri-industry waste streams for development of products, which can be applied, to agricultural and horticultural soils. There are a number of obvious advantages for utilisation of agri-industry waste streams in this way (Cameron et al, 1996). These include: conservation of water resources

protection of freshwater and marine environments

reduction of landfill inputs

reduction of waste incineration

recycling of nutrients

improved organic matter levels in soils

improved nutrient status of soils

Currently, there is little compiled information on agri-industry wastes produced in Victoria. Furthermore, wastes from such industries are often by default deemed as prescribed wastes making land disposal an expensive option. Surveying and characterising these wastes is essential before any assessment can be made of their re-use potential. If the waste streams are non-toxic and free of contamination, they can be effectively re-used by careful selection and suitable pre-treatment. By combining different waste streams, high nutrient value composted materials with consistent physical and chemical characteristics could be produced and tailored to suit various crop and soil requirements. This report presents a survey of post farm-gate agri-industry wastes produced in the Melbourne/Metropolitan region that have potential for development as soil ameliorants or fertilisers. The survey comprised of EPA data collected over a 12- month period on biodegradable organic wastes transported in the Melbourne/Metropolitan area and anecdotal information obtained from industry sources and waste management facilities. On the basis of this information, samples of a number of these waste streams were collected and chemically analysed for nutritive value and contaminants. Two of these wastes were subsequently selected for further investigation into recovery and reuse strategies. In two of these studies, blending and composting with domestic green-waste was employed to remediate the wastes resulting in reusable products which could be employed in horticultural and agricultural operations as soil conditioners or mulches. The results of these studies are presented in the second section of this report.

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1.1 Survey of Putrescible Wastes in Melbourne/Metropolitan Area This section of the report contains information on biodegradable prescribed waste streams and some additional information on movements and reuse of non-prescribed wastes generated from post-farmgate agri-industry operations in the Melbourne –Metropolitan region. This project is very timely in view of recent Victorian government initiatives to reduce the amounts of biodegradable materials being disposed of in landfills1. It is estimated that currently 1.7 million tonnes of organic wastes (some 40% of the total waste stream) are sent to landfill each year in Victoria and the recently launched Green Waste Action Plan aims to reduce this amount by 50% over the next ten years. Many of these biodegradable wastes originate in post-farmgate agri-industry facilities. Wastes from agricultural industries have great potential for re-use as sources of water, organic matter, nutrients, mulches or soil conditioning agents2. Currently, there is little compiled information on agri-industry wastes produced in Victoria. Furthermore, wastes from such industries are often by default deemed as prescribed wastes making land disposal an expensive option. Surveying and characterising these wastes is essential before any assessment can be made of their re-use potential. If the waste streams are non-toxic and free of contamination, they can be effectively re-used by careful selection and suitable pre-treatment. By combining different waste streams, high nutrient value composted materials with consistent physical and chemical characteristics could be produced and tailored to suit various crop and soil requirements. Landfill tipping costs in Victoria are relatively low which has in the past acted as a disincentive for waste producers and indeed waste management companies to explore other options for the disposal of biodegradable wastes. However, in 1998 the Environment Protection Authority (EPA) unveiled a new Industrial Waste Strategy, which was specifically targeted at solid and liquid wastes generated by Victorian industries (EPA Industrial Waste Strategy 1998)3. One of the key strategic objectives announced in the strategy was to minimise the economic value of resources during their life cycle through re-use, recycling and energy recovery in preference to disposal. In order to achieve this goal, it is essential that options for re-use of waste streams be explored and a principal aim of this present investigation was to identify, characterise and establish whether various post-farmgate agri-industry waste streams had potential for re-use. The study was divided into two phases, the first of which was a survey of recorded information on prescribed putrescible waste streams from agri-industry activities in the Melbourne region. Surveys of non-prescribed waste streams were also carried out although no records were available on the movement of these wastes. This report contains expanded and additional information relating to this phase of the project. In the second phase of the project two waste streams were selected for further study to demonstrate a technique for remediation of putrescible wastes by streaming them into green-wastes of domestic origin. Comprehensive details of this component of the study have already been provided in the final report and will consequently not be covered in any detail in this report.

1 ‘Waste Disposal and Water Management in Australia, October/November 2000, p20 2 Rechcigl, J.E., and H. C. MacKinnon, Agricultural Uses of By-Products and Wastes, American Chemical Society, 1997 3 EPA Industrial Waste Strategy Zeroing in on Waste: Pathway to Cleaner Production in Victoria, April 1998

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Waste Stream Surveys The aim of the first phase of the project was to survey the Melbourne – Metropolitan region in order to: survey and classify waste streams from a number of agri-industry activities in the

Melbourne/Metropolitan region according to nature, volume and potential for re-use, chemically and physically characterise a range of raw wastes to determine their suitability as

agricultural and other resources. The first part of the survey was conducted on data supplied by the Victorian Environment Protection Authority (EPA) which consisted of a list of prescribed transported putrescible (biodegradable) wastes recorded in the Melbourne region from January to December 1997 that were being transferred to landfills or being applied to land. This was the most recent documented information on prescribed putrescible waste available at the time of initiating the study. The data was supplied as uncollated transport events identifying the general waste type, volume (or weight in certain cases), postcode of source, type of disposal, transporter and date of movement. No information was available regarding the exact location or the nature of the operation that produced the waste although in most cases the description of the waste stream gave an indication of the industry involved. The data was then divided into monthly components and examined for information relating to wastes generated from post-farmgate agri-industries. This data was subsequently extracted and collated according to the waste type. On the basis of this information, a number of companies were contacted to investigate specific types of wastes produced and obtain samples for analysis and assessment. The second part of the survey involved collection of anecdotal data based on information obtained from Agriculture Victoria, several major waste management companies, commercial composters and various industry sources (telephone and in-person interviews). A number of non-prescribed waste streams were identified in this survey and information obtained regarding nature and reuse potential. Some of these wastes were sampled and analysed for nutritive value and contaminants. 1.2 Prescribed Waste Survey Findings The data obtained from the Environment Protection Authority4 was collated and separated into waste types. The data for each month was then summarised and tabulated. The information was also plotted to provide information regarding seasonal trends in waste production and movement. The information obtained for each of the major prescribed waste streams is provided in Table 1. The following sections contain descriptions of each of these waste streams. Grease trap wastes were not studied in any detail as they are not an agri-industry waste and are extensively recycled.

4 EPA Putrescible Waste Stream Data 1997.

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Table 1 Collated Volumes of selected waste streams in the Melbourne – Metropolitan region from January to December 1997 (source Victorian EPA) Volumes (m3) of prescribed wastes transported per month in Melbourne Month Wool

Scour Liquid Poultry

Poultry Litter

Seafood Process-ing

Tannery Prcoess-ing

Meat Process-ing

Dairy Process-ing

Potato Process-ing

Grease Trap

Jan 338 168 702 50 56 507 1225 191 2837 Feb 370 193 88 47 151 376 959 823 2407 Mar 319 164 48 83 232 495 983 717 2474 Apr 435 191 72 133 353 546 1086 651 2697 May 437 212 40 196 194 644 937 853 2948 Jun 447 187 56 169 442 368 1189 771 2692 Jul 732 226 40 255 685 409 1289 806 3228 Aug 398 213 56 371 535 444 2079 1064 2648 Sept 1143 202 40 769 580 489 3289 1004 2598 Oct 1372 225 64 629 526 666 2184 1082 2868 Nov 984 195 48 552 763 625 1741 850 3045 Dec 1126 224 32 489 186 868 2589 2902 3009 Total 8101 2400 1286 3743 4703 6437 19550 11714 33451

1.3 Wool Scour Wastes Wool scouring is a major industry in Victoria, with the majority of the nation’s wool processing plants situated in the Melbourne and Geelong areas. All of the waste stream data in Table 1 above is generated in the Melbourne–Geelong area although it is impossible to attribute waste volumes to particular companies apart from the anecdotal information provided by three of the companies that agreed to participate in the survey (Table 3). The waste volumes tabulated are for wool scour sludges that comprise of dirt, grease, salt and moisture. These sludges are formed as a result of deposition of suspended solids from scour liquor and effluent in settling tanks. These residues are then dewatered and thickened prior to disposal in a landfill. Data supplied by the EPA was in both volume (m^3) and weight (kg) and the latter was converted into volume assuming an arbitrary density of 1g/cm3. A plot of the waste volumes (sludge and solids) each month was constructed in order to observe any seasonal trends in the information (refer Figure 1). The data indicates that over 70% of the sludge transported in Melbourne occurred in the second half of the year and most of this movement occurred in the last 4 months of the year (57%). This is an important observation that would need to be considered when developing waste management strategies for wool scour sludges if they are to be blended with other waste streams in the area. Figure 1. Total wool scour waste volume (sludges and solids) transported to landfill in Melbourne in 1997 versus month

TOTAL WOOL SCOUR WASTE VOLUME ( SLUDGES AND SOLIDS) VS MONTH

0200400600800

1000120014001600

Jan Feb Mar Apr May Jun Jul AugSep Oct Nov Dec

MONTH

VOLU

ME

( m^3

)

5

There are altogether six wool-scouring operations in the Melbourne –Geelong region. Four of these companies agreed to take part in this survey. The waste streams identified in each facility are listed in Table 2. Three of these companies dispose of wool scour wastes by a combination of landfill and discharge to sewer (treated effluent). The sixth company (Geelong Wool Combing) has put in place a comprehensive waste management site plan that remediates all wastes and has resulted in the generation of a valuable soil ameliorant (see later). The other two companies are currently disposing of the sludge on a rural property in the Geelong area (under an EPA license) but this can only be considered as a short-term option due to the limited space available and the slow rate of decomposition of the sludge. This option would also appear to have environmental problems such as the potential for surface and groundwater contamination and generation of odour. Table 2 Waste types generated in the wool scouring process

Waste Type Description Scour Sludge Prescribed sludge, basically grease (lanolin) and dirt. Centrifuged out of

wash water along scour line.

Dirt and Fibres Short fibres, dirt and seeds etc, removed before scouring by agitation in the ‘double-drum’.

Wash Effluent Large volume of dirty water from washing process. This is disposed of via the sewer system (Melbourne Water) at a cost based on pH, BOD and turbidity.

Three of the wool scouring companies that used landfilling as a waste disposal option were surveyed and details of waste produced at each of these sites are listed in Table 3. These companies also agreed to supply sample of each waste stream for analysis and the results are listed in Table 4. Each company essentially has three major waste streams, namely sludge, a mixture of dirt and fibre and liquid effluent. The liquid effluents were not sampled as the current study was only concerned with solid wastes. It should however be noted that wool scour effluents can pose significant environmental problems due to their high biochemical oxygen demand (BOD) and high salt content. It is assumed that wastewater treatment facilities receiving wool scour effluents will be able to significantly degrade its pollution load before discharging to the environment. The discharge of wool scour effluents to reticulated sewage systems operated by water authorities (eg Melbourne Water) is not subject to EPA controls but the sewage system operator is answerable to the EPA if their discharges do not meet appropriate State Environment Protection Policies (SEEPs). There have been recent advances in the reduction of contaminants in wool scour effluents (eg the Siroscour process developed by the CSIRO) and also improved chemical flocculation agents such as Sirolan CF which can reduce the BOD of wool scour effluent by as much as 75%5. Combinations of these developments have the capacity to greatly reduce both the cost of disposal of these effluents and their environmental impact.

5 Taylor R., Wool wastes: turning a problem into a valuable resource, CSIRO Division of Wool Technology, Belmont, 1996

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Table 3 Wool scour wastes generated per week at three Melbourne wool-scouring operations

Source Waste type Waste Volume Disposal method

Port Phillip Wool Processing Pty Ltd

Sludge Dirt & Fibre Effluent

30 ton/wk 2-3m3/wk 4500KL/wk

Landfill Landfill Sewer

ConAgra Wool Pty Ltd


100m3/wk 3m3/wk Varies


Victoria Wool Processors Pty Ltd


20-30ton/wk 2-3m3/wk Varies


Table 4 Analytical results for wool scour sludge and wool fibre/dirt wastes from three companies

Industry Waste

Selected Nutrients % Selected Heavy Metals (mg / L)

N P K Cd Cr Cu Co Pb Zn As Hg Wool Sludge Average of three sites

0.84 <0.06 0.425 <1.0 24 <0.001 <0.001 <10 0.007 2.25 0.025

Wool Fibres Plus Dirt Average of 3 sites

2.6 0.15 1.38 <1.0 17 0.002 <0.001 <10 0.007 2.1 0.025

The sludge and dirt/fibre waste streams from the three facilities contained significant levels of chromium and arsenic although it is unlikely that this would pose serious problems for the reuse of these waste streams for the preparation of composted soil ameliorants. The Australian Standard for composts, soil conditioners and mulches states that any of these materials must conform to the unrestricted use (Biosolids Class A) limits to pass. Currently in Victoria, the limits in the Agriculture and Resources Management Council of Australia and New Zealand Water Technology Committee (ARMCANZ) ‘Guidelines for Sewerage Systems: Biosolids Management’6 are used however these will be superseded when the new Victorian Guidelines for Biosolids (currently in draft form) are adopted. The Australian Standard for composts, soil conditioners and mulches7 and the ARMCANZ guidelines for Biosolids both list s permissible levels for arsenic and chromium as 20 and 400 mg/kg respectively. Both of the waste streams described in Table 4 confirm with these standards for agricultural use. If both of these wastes were to be subsequently composted by blending with other waste streams then the levels would be reduced further. The composted wool scour sludge described below has a chromium level, 20mg/kg and an arsenic level of < 2mg/kg.

6 Guidelines for Sewerage Systems- Biosolids Management, Agriculture and resource management council of Australia and New Zealand, Water technology Committee, Occasional paper WTC No 1/95, October 1995 7 Standards Australia, Australian Standard AS4454- Composts, Soil conditioners and Mulches Standards Association of Australia, Homebush, NSW, 1999

7

As mentioned above, one wool combing operation in Geelong has instituted a comprehensive waste management program that has resulted in the production of a value added soil ameliorant. This information is kindly supplied by Geelong Wool Combing and the State Chemistry Laboratory Werribee Victoria. The process involves the blending of wool scour sludge with other materials and composting under carefully controlled conditions to produce a nutritive rich compost that is now used extensively in the horticultural product market The ingredients used in the composting procedure are themselves sourced from other wastes generated from industries in the vicinity. To compost the wool scour wastes GWC incorporated wood chip wastes as the bulking agent (carbon source) and waste hair from the hide and skin processing industry (nitrogen source) 8. Effluent, high in potassium, from its own plant was used for watering during composting and as a potassium source. The resulting compost has recently been used in trials (SCL Werribee) in nearby vegetable growing area with promising results. The soils from the market gardening area of Werribee, that has been continuously cropped for over 30 years, has poor organic matter content and soil structure. Application of soil organic ameliorants has been recommended to increase the sustainability of these soils. Results in Table 5 show that trials on broccoli with composted wool scour wastes have shown that application of compost can, assist in the conservation of soil moisture resulting in reduced water application by about 12%

(equivalent to about $22.50 ha-1 per annum),

decrease in soil bulk density resulting 12% increase in aeration porosity that contributes to a more conducive environment for root penetration and growth,

significantly contribute to the nutrient input, and

significantly reduce the residence time of the crop contributing to early harvest. Table 5 Soil properties and broccoli harvest results after land application of composted wool scour waste

Compost Applied (t ha-1) Properties measured (After week 4/5) 0 20 80 Soil Moisture (%) 15.4a 17.9b 20.8c Loss on Ignition of Soil (%) 5.5a 7.1b 10.4c Soil Bulk Density (g cm-3) 1.31a 1.26b 1.08c Aeration Porosity (%V/V) 30.1a 28.9a 35.3b After 11.5 weeks No. Of Broccoli Heads Harvested (X10-3 ha-1) 22.1a 30.1b 32.8b

Wool scour effluents also have great potential for reuse in view of their very high potassium content. The effluent that is generated from the wool scouring process is called suint. The effluent from the first wash of the wool with hot water is free of detergent or other chemical additives. CSIRO has developed a technique to reduce the volume of this wash by evaporation and reduce the suspended soil particles, grease and wool by centrifugation. This concentrate was analysed and found to have a high potassium content (about 11% w/w). Other nutritive elements were comparatively low in concentration and offered little value for agronomy. Levels of heavy metals and organic chemical residues were inconsequential in relation to environmental pollution and toxicity. 8 http://www.gwc.net.au/default.htm

8

Replicated field trials were conducted (SCL Werribee Victoria) with potatoes and pastures (where potassium nutrition is important). The concentrate was diluted to several concentrations and applied to pasture and potatoes at comparable rates to regular potassic fertilisers such as potash. The results from the pasture trials have shown that the suint with appropriate dilution can be used as an alternative potassium source and pasture yields obtained are comparable to those obtained using conventional potassic fertilisers (Table 6). Table 6. Pasture yield under fertiliser and suint treatments as sources of potassium

Pasture Yield At various sites

P fertiliser only (Control)

P + Potash as K source

P + Suint as K Source

Tonnes Ha-1 Portarlington 1.9a 2.5b 2.4b Simpson 8.1a 9.1b 9.2b Larpent 5.3 5.6 5.7 The results from the pasture trials also showed that potassium uptake by the pasture was comparable between K sources (Table 7). Table 7. Potassium uptake in pastures under fertiliser and suint treatments as sources of potassium

Potassium uptake

At various sites




Kg Ha-1 Portarlington 26.5a 43.6b 42.7b Simpson 128.9a 237.0b 226.5b Larpent 111.3a 162.9b 166.5b

Trials with potatoes showed that the yields of potatoes and potassium concentration in potatoes, treated with different sources of potassium, were comparable, but not significantly different from the nil K treatment (Table 8). A possible reason for the lack of difference was the leaching of potassium at this sandy site. Table 8. Yield and potassium uptake in potatoes treated with different forms of potassium

Control (nil K) Potash as K source Suint as K source

Yield (tonnes ha-1) 41.7 45.6 41.9 K concentration (%) 1.89 2.00 1.91

These studies show that,

suint could be used in agriculture without affecting the yield of the crop,

the uptake of K and yield of crops in some circumstances (e.g. pasture) can be comparable to conventional potassic fertilisers such as potash

the cost of production of conventional fertilisers and suint should be compared to determine whether suint is a financially viable alternative.

9

Summary In summary this survey of wool scour wastes transported as prescribed wastes in the Melbourne-metropolitan region has shown that: large volumes of wool scour sludges are disposed of in landfills in the Melbourne region each year

particularly in the latter part of the year

the sludges are relatively free of contamination

the majority of wool scour sludges that are generated are not reused in any way (land disposal of untreated sludge would appear to be only a short term option and could pose environmental problems such as surface water pollution, odour, groundwater contamination)

all wool scour companies surveyed acknowledge that solid and liquid wastes from these operations pose significant environmental problems as well as the burden of the high disposal costs and that alternatives to landfilling and disposal to sewer must be found.

wool scour sludges can be effectively composted by blending with other agents such as wood chip waste and animal hair to produce a product which has high value as a soil ameliorant and fertiliser thus completely eliminating landfill disposal of this waste stream

wool scour effluents can be reused as a potassic fertiliser or as a water source in wool scour sludge or other composting operations

technologies are available to greatly reduce the pollution load of wool scour effluents with subsequent reduction of disposal costs and environmental impact.

1.4 Tannery Wastes Tanneries take raw skins from abattoirs and process them into tanned, hairless leather for export and leather goods manufacture. This process produces a variety of chemical and biological wastes that consists of large quantities of effluent, flesh cut from hides, fleshy scrapings, fatty tissue, hair, sludges from various stages of the process, and chromium treated leather trimmings. Rendering and pet food companies take some animal tissue. A typical leather processing involves pre-tanning steps, tanning, post-tanning and finishing steps. The raw hide is first subjected to a soaking process to clean the hide of dirt, blood, flesh, grease, dung etc. (various chemical agents are used at this step) and then unhaired, degreased and pickled before turning into leather. These are the pre-tanning operations and use a range of chemical agents that result in large volumes of contaminated effluent. It is estimated that around one third of the total pollution load from the leather industry comes from these steps. The tanning step involves the use of chromium solutions that are responsible for the generation of chromium containing effluents and sludges that are the major pollution problem in the entire tanning process. Almost all tanneries worldwide use the chrome process although in some countries a more traditional and environmentally friendly process involving the use of natural agents such as barks and nuts (vegetable tanning) is carried out. The post-tanning and finishing steps also involve the generation of effluents containing unabsorbed oil, dyes tannins and chromium. It is estimated that some 3000L of liquid effluent can be generated from the processing of 100kg of animal hide. Sludges produced at various stages of the process (fatty sludges and chromium sludges) are generally mixed and disposed of to landfill. The hair removed at the pre-tanning stage is disposed of by landfilling as a prescribed waste. One of the companies that participated in this current survey estimated that they process up to 90 tonnes of hides per week and

10

the cost of disposal of waste hair is a significant proportion of the total operating cost (approximately $30-40 per tonne). Leather manufacture is a major industry in the Melbourne region, with some 64 registered companies involved in hide and skin processing operations. The waste stream data on movements of prescribed wastes for this industry is provided in Table 1 and contains information recorded for the Melbourne area. It is not possible to attribute waste volumes to particular companies apart from the anecdotal information provided by two of the 14 companies that participated in the survey. The waste volumes provided in Table 1 are for tannery sludges that consist of mixed sludges (see below) and partly digested hair. All data supplied by the EPA recorded the waste streams in volumes (m^3). A plot of the waste volumes (sludge and solids) each month was constructed in order to observe any seasonal trends in the information (refer Figure 2) Approximately 75% of the total waste stream volume of solid tannery wastes is transported in the five-month period from June to November, which suggests that most companies stockpile the wastes on-site prior to disposal in the later months of the year. The comparatively low volumes transported in the December to March period coincide with the annual holiday period. The volumes transported then slowly build as the wastes accumulate. This is not the case with liquid effluents that accumulate rapidly and are disposed of on a more regular basis. Two of the companies that participated in the survey provided information on the nature and volume of their solid waste streams and also supplied samples for analysis. Table 9 below lists the waste stream descriptions and Table 10 lists the estimated weekly waste stream volumes from each facility. The results of analysis of each waste stream are provided in Table 11.

Figure 2 Total tannery waste volume (sludges and solids) transported to landfill in Melbourne in 1997 versus month

TOTAL TANNERY WASTE VOLUME VS MONTH

0

200400

600800

1000

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

MONTH

VOLU

ME

(m^3

)

11

Table 9 Waste types generated in the leather tanning process

Waste Type Description Hair Hair removed from skins from lime-sulphide stripping; waste hair is

clumped and wet.

Fatty-Sludge Fatty tissue and residue removed from hides and separated out from other waste. Contains some fleshings and is mixed with Cr-sludge for disposal.

Cr-Sludge Partially digested tissue and chromium waste from the tanning process; a heavy, uniform dark blue/green sludge-waste of most environmental concern.

Table 10 Tannery wastes generated per week at two Melbourne operations

Company Waste type Waste Volume Disposal method

Victorian Hide & Skin Processors Pty Ltd (VHSP)

Hair Sludge (fatty & Cr)

50m3 /wk 40m3/wk

Landfill

AusTanners Pty Ltd Hair Sludge

10-12m3 / wk 12ton/wk

Landfill

Table 11 Analytical results for tannery wastes from two companies

Industry Waste

Selected Nutrients % Selected Heavy Metals (mg / L) (wet weight basis) (wet weight basis)

N P K Cd Cr Cu Co Pb Zn As Hg

Tannery sludge Average of two sites

1.2 0.33 .0.07 <1.0 3500 0.002 <0.001 <10 0.014 1.5 0.02

Tannery sludge (Cr) Average of two sites

0.79 <0.06 0.11 <1.0 64000 0.002 0.003 <10 0.088 1.0 0.08

Tannery Fatty sludge Average of two sites

0.67 <0.06 <0.04 <1.0 65 <0.001

<0.001 <10 0.002 - <10

Tannery Hair Average of two sites

4.95 <0.06 <0.04 <1.0 81 <0.001

<0.001 <10 0.009 0.1 0.07

Tannery sludges from the latter stages of the tanning process (designated Tannery Sludge and Tannery Sludge Cr) were found to be particularly high in chromium and consequently could not be used directly in agricultural applications. Both of these waste streams are well above the ARMCANZ Biosolids guidelines for chromium of 400mg/kg. The chromium level in the Tannery Sludge (Cr) is sufficiently high to warrant investigation into chromium recovery and possible reuse of the decontaminated sludge. The fatty sludges were relatively free of contamination and as these wastes do not originate from processes involving the use of chromium, it would seem likely that the source of the

12

chromium detected is from cross- contamination. The level detected is still well below the ARMCANZ Biosolids guideline and should be investigated for reuse. This waste stream has potential for bioremediation and there are reports of biotechnology techniques to treat these waste streams9. We were unable to find any company in Melbourne that was carrying out this waste treatment. Tannery hair was found to be high in nitrogen and the chromium levels detected in the sample obtained would suggest that this material has also been cross contaminated by waste streams at a later stage of the process. The chromium level (81mg/kg) was well below the ARMCANZ guidelines and consequently this material has great potential for reuse as a nitrogen source. In the previous section, hair waste from a tannery operation was demonstrated to be an effective nitrogen source in the blended compost generated from wool scour sludge, ground wood waste and tannery hair, Recently the State Chemistry Laboratory, funded by the Department of Industry, Science and Tourism assisted a Victorian Tannery to characterise their waste, identify suitable markets, and conduct trials to study the suitability of the wastes for alternative uses. As a part of that study, partly hydrolysed hair wastes were investigated as nutritive-rich mulch for vegetable production. The State Chemistry Laboratory kindly supplied the results described below with permission from Victorian Hide and Skin Processors Pty Ltd. Analysis of the hair waste stream showed that on a dry weight basis the waste contained approximately 12% nitrogen and negligible levels of heavy metals (all below ARMCANZ guidelines), and common pesticides. Table 12 Concentration of plant nutrients and heavy metals in waste hair. Nutrients and inorganic contaminants Organic contaminants Units Conc. mg kg-1 P % <0.06 Organochlorins

(α-BHC, β-BHC) <0.02

K % <0.04 Hexachlorbenzene <0.02 Ca % 4.10 Aldrin <0.02 Mg % 0.33 Lindane <0.02 Na % 1.10 Heptachlor <0.02 Mn % 0.003 Heptachlor Epoxide <0.02 Fe % 0.16 Dieldrin <0.02 DDE <0.02 Cd mg kg-1 <0.50 DDD <0.02 Cr mg kg-1 31.7 DDT <0.02 Cu mg kg-1 8 Endrin <0.02 Pb mg kg-1 <10 Oxy-Chlordane <0.02 Ni mg kg-1 <6 cis-Chlordane <0.02 Zn mg kg-1 123 trans-Chlordane <0.02 As mg kg-1 <0.2 Total Organophosphates <0.05 Hg mg kg-1 0.51 The nitrogen in hair was organically bound and was not available for immediate release. Trials with lettuce were conducted in the Werribee market garden area to evaluate the suitability of hair as an alternative source of nitrogen fertiliser. Milled, waste hair was surface applied to the soil at rates equivalent to up to 400% of nitrogen that is normally applied as conventional fertilisers to take

9 http://www.biotechsupportindia.com/leather.htm

13

account of the lower N availability of the hair waste compared to the commercial fertiliser. The application of nitrogen as hair proved to be useful in two ways, first as an organic soil ameliorant preventing moisture loss from the soil and second as an alternative source of nitrogen as a slow release fertiliser. Table 13. Soil and lettuce characteristics as affected by application of waste hair as an alternative source of nitrogen and moisture retaining agent.

Nitrogen applied as hair or fertiliser Properties measured (After week 3) 0 100% - fertiliser 100% - hair 400% - hair Soil moisture (%) 15.6a 15.6a 15.8a 16.4a Plant N content (%) 4.7a 4.9a 4.7a 5.2b Plant size - width (cm) 29.8a 29.8a 30.2a 31.4a Yield (t ha-1) 76.3a 83.3a 90.8a 94.7a N uptake (t ha-1) 2.74 3.23b 3.24b 3.39b

The study has shown that waste hair from tannery wastes can be used as an alternative source of nitrogen and moisture retaining mulch in vegetable production. Significant differences were obtained for soil moisture, plant N content, plant size, and yield in plots treated with sufficient hair waste to provide 4 times the required nitrogen amount compared to commercial fertiliser application. There were also significant increases in yield and N uptake for plots using 100% of it’s N requirement from hair waste compared to plots that did not have any fertiliser applied. This observation further demonstrated the effectiveness of the material as a moisture-retaining agent with nutritive value. The results also showed that moisture retention under surface application of hair waste was greater than under the control with no nitrogen (Table 13). Similar differences were found for plant characteristics such as plant N concentration, plant size, yield and N uptake. Land application of partially hydrolysed and milled hair wastes from tanning operations would therefore appear to have great potential fro reuse as a slow release N fertiliser and mulch without any pre-treatment (apart from washing) such as composting. However, sanitisation by a composting process carried out in accordance with the Australian Standard in which the waste is blended with other biodegradable wastes (eg a low N content material such as bark, cereal husks etc) would be a preferred option to ensure a safer product and higher nitrogen bioavailability. Summary In summary this survey of hide and skin tanning wastes transported as prescribed wastes in the Melbourne-metropolitan region has shown that: leather manufacture is a major industry in the Melbourne region, with some 64 registered

companies involved in hide and skin processing operations

large volumes of tannery sludges and partly hydrolysed hair wastes are disposed of in landfills in the Melbourne region each year particularly in the latter part of the year

waste streams from leather tanning operations include, large quantities of effluent (approximately 3000L per 100kg of hide treated), flesh cut from hides, fleshy scrapings, fatty tissue, hair, sludges from various stages of the process and chromium treated leather trimmings.


all tanneries surveyed acknowledge that solid and liquid wastes from these operations pose significant environmental and disposal costs and that alternatives to landfilling must be found.

14

tannery sludges from the latter stages of the tanning process (designated Tannery Sludge and Tannery Sludge Cr) were found to be particularly high in chromium and consequently could not be used directly in agricultural application

sludges from various stages of the process are often cross-contaminated and mixed together rather than separating recyclable sludge from heavily contaminated sludge

the fatty sludges were relatively free of contamination and should be investigated for reuse; this waste stream has potential for bioremediation

tannery hair was found to be high in nitrogen and the chromium levels detected in the sample were well below the ARMCANZ guidelines and consequently this material has great potential for reuse as a nitrogen source

waste hair from tannery operations can be used as an alternative source of nitrogen and a moisture retaining mulch in vegetable production and also has demonstrated potential as a nitrogen source in blended waste composts

1.5 Food Processing Wastes Food processing is an important industry in Victoria with in excess of 3000 registered companies producing a wide variety of foods for human consumption. Many of these operations are in the Melbourne-Metropolitan area. These include, seafood, meat, smallgoods, dairy, fruit and vegetable, and confectionery processing and manufacturing operations as well as health, cereal and frozen food manufacturers. They also include many large raw product facilities (eg wholesale markets, dairies, abattoirs etc). There are also over 200 pet food producers located in the Melbourne region. The sheer size of the food industry and the waste streams produced made it impossible to carry out a comprehensive survey on this sector, however, on the basis of the prescribed waste survey and some anecdotal information on non-prescribed waste streams, some information was obtained on several industries that have potentially recyclable biodegradable waste streams that are currently disposed to landfill. In contrast to the other industries surveyed, we experienced significant difficulty in obtaining quantitative information from many food-processing operations (particularly packaged food manufacturing operations) as they regarded the information as highly confidential. All of the waste stream data listed in Table 1 is generated in the Melbourne area although it is impossible to attribute waste volumes to particular companies or to particular types of operation except in some cases where the waste product is identified specifically (eg cheese, milk, fish offal etc). Wastes are listed according to broad industries (eg meat processing, seafood processing). Some more specific information was obtained from a number of the 26 of the companies that participated in the survey. Data supplied by the EPA was in both volume (m^3) and weight (kg) and the latter was converted into volume assuming a density of 1g/cm3. A plot of the waste volumes (from meat, dairy, potato and seafood processing operations) each month was constructed in order to observe any seasonal trends in the information (refer Figures 3-6). This is important information on the availability of particular raw materials that would need to be considered when developing waste management strategies for putrescible waste streams if they are to be blended to produce value added fertiliser products or soil conditioners. Seafood wastes The waste volumes in Table 1 and Figure 3 appear to be low considering the size of the industry, which involves approximately 250 companies throughout Victoria in seafood processing, and wholesale fish supply operations. This is due to the fact that most of the solid wastes produced are

15

recycled as pet food and fertiliser and relatively small amounts are transferred to landfills. The EPA data did not provide any information on this waste movement. The waste stream listed in the EPA data consists mainly of skins (eg shark), offal and shell. Over 80% of this waste transport occurs over the second six months of the year (65% in the last 4 months) which is most likely a reflection of seasonal factors relating to the type of activities taking place in the Victorian fisheries in the spring – summer. There could also be some stockpiling of less offensive wastes (eg shell) prior to disposal.

Figure 3. Total seafood volume (solids) transported to landfill in Melbourne in 1997 versus month Meat Processing The waste volumes in Table 1 and Figure 4 appear to be low considering the size of the industry which involves over 1500 companies throughout Victoria in abattoirs, wholesale butchers, meat packaging, smallgoods manufacture and retail meat supplies. This is due to the fact that most of the solid wastes produced are recycled for pet food, fertilisers and rendered to extract useful components and relatively small amounts are transferred to landfills. The EPA data did not contain any information on this waste movement. One rendering company contacted reported that approximately 400,000 tonnes of meat and bone wastes are treated per year at its sites10. The volumes reported in Table 1 are for processing effluents mainly originating from abattoirs. Abattoirs produce large volumes of liquid effluent that is generally disposed of by application to land. This effluent should be investigated as a possible water source in composting operations. No samples of this liquid effluent were obtained for analysis. The waste movements are relatively steady over the year with the largest volumes recorded in December probably due to the larger local consumption of processed meat products during the Christmas / New Year period.

10 personal communication, industry source

TOTAL SEAFOOD WASTE VOLUME VS MONTH

0

200

400

600

800

1000


MONTH

VOLU

ME

(m^3

)

16

Figure 4. Total meat processing (solids) transported to landfill in Melbourne in 1997 versus month Dairy Processing The dairy food industry involves around 500 companies throughout Victoria in dairies, dairy product manufacture, cheese manufacture and milk production and approximately 60 % of these is in the Melbourne-Metropolitan region. The waste stream data for this industry listed in Table 1 and Figure 5 are mainly for cheese whey and sludges from cheese manufacture. A little less than 70% of this waste transport occurs over the second six months of the year which is most likely a reflection of seasonal factors. Large quantities of wastewater are also produced in this industry and recently a major company in this sector participated in a cleaner production program to reduce cheese solids in these waste streams, which are sent to wastewater treatment plants11.

Figure 5. Total dairy waste (solids) transported to landfill in Melbourne in 1997 versus month

11 http://www.environment.gov.au/epq/environet/eecp/location.html#6

MEAT PROCESSING WASTE VOLUME VS MONTH

0200400

600800

1000


MONTH

VOLU

ME

(m^3

)

DAIRY WASTE VOLUME VS MONTH

0500

100015002000250030003500


MONTH

VOLU

ME

(m^3

)

17

According to the EPA data, these recorded whey and sludge wastes are landfilled and should be investigated for reuse or incorporated into other waste streams for remediation by composting in view of their nutritive value. Cheese whey is a source of phosphorus and potassium and most of the nutrients are inorganic constituents or simple organic compounds making them readily bioavailable. These wastes are also generally quite acidic which may also make them suitable for blending with biodegradable alkaline waste streams. Potato Chip Processing There are some 30 potato chipping companies in Victoria and approximately two thirds of these operations are in the Melbourne-Metropolitan area. The waste stream data for this industry listed in Table 1 and Figure 6 are mainly for potato scrap (peelings, whole potatoes, potato pieces, dirt) and sludges from the chipping process. A little over 70% of this waste transport occurs over the second six months of the year, the largest waste streams being recorded in December where industry sources reported that production in some facilities can double.

Figure 6. Total potato waste (potato scrap and sludges) transported to landfill in 1997 versus month Potato waste case study Potato wastage produced in the potato crisp industry have potential to be recycled using windrow composting and were selected for further study. Table 14 lists information on the waste streams produced by a large Melbourne snackfood manufacturer ( Snack Brands Australia) that participated in this study.

Table 14 Potato waste produced per week at the Snack Brands operation in Victoria Waste type Waste volume Disposal method Scrap potato 48m3/wk Landfill Sludge 12000L/wk Pretreatment and landfill

During the preparation stage, where potatoes are cleaned and skinned prior to chipping, whole potatoes are passed through conveyers to be washed, shaved then sliced before conversion into crisp chips. The wastes that are generated through this process include whole potatoes, potato scraps, peelings, dirt and potato sludge. The waste material that was of interest in this study is the high moisture content potato scraps and peelings. Chemical analysis showed that this waste was free of contamination and as it has such high water content, it is potentially a moisture source for the

POTATO WASTE VOLUME VS MONTH

0500

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composting process. The strategy employed in this study was to blend potato wastes in with green-waste at a conservative level (approximately 20% by volume) to determine if the wastes could be effectively treated and not interfere with the composting process. This study was carried out on a commercial scale using full sized windrows. The study is described in detail in the second section of the report. The bulk of the potato waste was a composite of potato shavings, potato solids dirt. Twenty samples of equal volume (approximately 1 L) were removed from each stage in the process and submitted for chemical analysis. The chemical characteristics and physical nature of the potato wastes are listed in Tables 15 and 16. Table 15 Characteristics of potato scraps and peelings 2000 Industry Waste Selected Nutrients (Unit)* %w/w mg/kg N P K Cd Cr Cu Pb As Potato shavings 1.7 1200 16000 <0.5 <0.5 8 <10.0 0.056 Potato solids 1.6 1700 13000 <0.5 <0.5 4 <10.0 <0.05 Potato shavings & dirt 1.3 1800 11000 0.5 0.5 20 <10.0 1800 *Results reported on a 400C dry weight basis Table 16 Analysis of %Moisture, pH, EC, C/N and Total N for waste from Potato Waste. Units Potato Scraps Potato Solids Potato & Dirt

Moisture (400C) % w/w 90.3 75.3 70.8 pH [H2O] 5.8 6.2 5.8 EC dS/m 1.7 4.1 15.1 Total Sodium * mg/kg 250 150 16000 Total Chloride* % w/w 0.11 0.44 3.7 Total Nitrogen * % w/w 39 35 25

*Results reported on a 400C dry weight basis The analytical results indicate that there is low level of contamination, especially cadmium that is known to accumulate in some potato varieties. Cadmium is the heavy metal of greatest concern, and caution must me taken in using soil ameliorants derived from potato waste as it may result in cadmium accumulation in soils. The wastes have a high moisture content, which makes them suitable for streaming into a composting operation as a water source. They have very low nutritive value but composting a better option than landfill disposal. 1.6 Poultry Processing Poultry farming is an important industry in Victoria with over 200 registered companies producing and processing poultry meat and eggs for human consumption. It is estimated that the industry produces approximately 90 million chickens for chicken meat each year12. The industry has grown rapidly over the past twenty years and many of these operations are located on the fringes of the Melbourne-Metropolitan area. The major waste streams from the sector are poultry shed litter / manure and poultry carcasses. The EPA data supplied suggests that relatively small amounts of waste from

12 http://www.vff.org.au/commodity/chicken/default.asp

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this sector are disposed of to landfill although the data does not include poultry mortality volumes that are very large. Table 1 and Figures 7 and 8 show the monthly movements of putrescible waste streams from this sector.

Figure 7. Total poultry litter transported to landfill in 1997 versus month

Figure 8. Total liquid poultry waste transported to landfill in 1997 versus month The above data is clear evidence that only a small fraction of the total poultry litter waste stream generated by the industry is not recycled when the overall size of the industry is considered. Industry sources report that poultry litter is almost completely recycled by use as fertiliser / mulch in horticultural production. It is estimated by the Victorian Farmers Federation (VFF) that between 300,000 m^3 and 400,000m^3 of shed litter is generated annually from the industry. However, there are concerns regarding the safety of using uncomposted poultry litter as a soil conditioner / fertiliser particularly in the production of minimally processed horticultural produce such as salad vegetables. There are currently guidelines in preparation for the composting and appropriate application rates for the land application of poultry litter in horticultural activities 13 13 R. Premier, personal communication, Institute for Horticultural Development Knoxfield

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Poultry carcasses are collected from farms, frozen and disposed in a special landfill designed for putrescible organic wastes. At the present time there is no rendering of this waste stream carried out due to concerns regarding disease transfer into feed stocks produced by this process. Composting is an effective technique for the treatment of this waste stream and is used extensively overseas to treat this waste. This is a huge waste stream and one company estimated that they collect and dispose of over 100 tonnes of chicken carcasses per week. Mortality rates in the industry are typically around 5% which would equate to over 7000 tonnes of bird carcasses per year. . There is clearly an urgent need to develop alternative strategies to landfilling of this waste stream and to this end the Victorian Farmers Federation through its recently launched Chicken Care Program is developing best practice guidelines for the safe treatment and disposal of chicken carcasses. The Chicken Industry Environmental care Initiative is designed to improve safety and environmental performance in the industry and operates under the auspices of the Victorian Farmers Federation and the Victorian Chicken Meat Council 14 15. In summary this survey of food processing wastes transported as prescribed wastes in the Melbourne-metropolitan region has shown that: the EPA data obtained is clearly not comprehensive for the food processing and related industries


food processing is a very large industry in the Melbourne Metropolitan area which produces a wide range of solid and liquid wastes which are currently transferred to landfill

in the seafood processing industry, most of the solid wastes produced are recycled as pet food and fertiliser and relatively small amounts (mainly shark skins, offal and shell) are transferred to landfills

most of the solid wastes produced in meat processing are recycled for pet food, fertilisers and rendered to extract useful components and relatively small amounts are transferred to landfills

abattoirs produce large volumes of liquid effluent which is generally disposed of by application to land

abattoir effluents should be investigated as a possible water source in composting operations

dairy food manufacture produces large quantities of cheese whey and sludges which have high potential for reuse due to high nutritive value

potato wastes produced in the potato chipping industry consist of peelings, whole potatoes, potato pieces, dirt and sludges

potato wastes can be remediated effectively and inexpensively by windrow composting with green-waste ( see second section)

the high moisture content of the potato waste has a slight cooling effect on the windrow but does not affect the composting process when added at a rate of 20% by volume ( see second section)

higher rates of potato waste could be remediated by this technique but further trials would need to be established to optimise the waste loading

14 http://www.vff.org.au/news/press/archive/news-165.asp 15 http://www.vff.org.au/news/press/archive/news-166.asp

21

chicken litter is a huge waste stream which is recycled into the horticultural production industry

there is an urgent need to develop guidelines for the composting and appropriate application rates for the land application of poultry litter in horticultural activities

there is an urgent need to develop alternative strategies to landfilling of bird carcasses from the poultry industry

1.7 Miscellaneous waste streams As part of the survey component of this study, some 150 companies in a wide range of industries were surveyed to obtain information on putrescible wastes that were being disposed in landfills. Some of the information obtained from these enquiries has already been presented. As previously stated, many companies are reluctant to provided detailed information on their waste management issues particularly in the food processing area. On the basis of this investigation, it appears that the EPA data on food processing wastes obtained only accounts for a small fraction of what is a huge waste stream. The following section describes information obtained on wastes generated in three sectors, namely, the nursery industry (in particular cut flowers), wine production and food processing. Cut Flower wastes A substantial waste stream that was identified as going to landfill, and having potential for re-use, was the off-cuts and waste from the flower growing industry. This is a major industry in Melbourne, with two main regions located in the Dandenongs and in the outer Southeastern suburbs. Eight companies ranging from small scale to large operations were surveyed and it was estimated that the total volume of waste being disposed to landfill was in excess of 4000m3 per year from these premises alone. In view of the fact that there are over 700 wholesale nurseries in the Melbourne –Metropolitan area the total wastes stream going to landfill from cut flower and other types of nurseries would appear to be very large. Flower growers are particularly concerned about pathogen and pesticide transfer, so wastes are generally not re-worked back into the soil, but dumped on site or sent to landfill 16 Table 17 lists the major types of wastes generated from these operations. The table only lists wastes identified in the cut flower industry however general nurseries also send large volumes of wastes to landfills mainly consisting of perished potted seedlings and mature plants which are too expensive to recycle17. Table 17 Typical wastes generated in cut flower operations

Waste type Description

Flower stems Cuttings from the base of flower stems produced in flower dispatch area

Discarded bulbs Old bulbs removed from field production site Diseased plants Whole plants including roots and potting medium Whole flowers Damaged or imperfect whole stems

A bio-remediation trial, using windrow composting, was carried out to assess the breakdown of pathogens and pesticides, to thereby assess the possibility of re-use as a soil-conditioning agent either by the growers themselves or sold through the nursery retail outlets. This study is described in considerable detail in the second section of this report and only the major findings will be described in this section.

16 G. Guy, personal communication, F & I Baguley, Plant and Flower Growers, South Clayton 17 Industry source, Dandenong nursery

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The strategy adopted was to investigate streaming of cut flower wastes into a commercial green-waste composting operation and to determine the optimal loading of the waste to effect remediation. The focus of the investigation was to destroy pesticides in the waste by the composting process. This required that the compost windrow be maintained at a sufficiently high temperature over an extended time to ensure complete decomposition of these contaminants. The results of this study using green-waste to compost contaminated cut flower waste clearly demonstrate the effectiveness of composting as a means of remediating this waste. The key outcomes of the study were: cut flower wastes can effectively be combined at a rate of 50% into a green-waste composting

operation without any significant effect on the composting process as indicated by the results of average core temperatures and physical measurements

residual pesticides in the cut flower waste were reduced to undetectable levels during the composting process

the resultant compost was suitable for land application based on the fact that the process operated within the standard AS44554-1999 for Composts, Soil Conditioners and Mulches

the materials produced in this process were demonstrated to be suitable for reuse either as a mulch or as a soil ameliorant / potting media component

the study has shown clearly that composting of cut flower wastes after blending with other green-waste is an effective and inexpensive means of remediating this significant waste streams with considerable cost savings to the producer

Wine production The wine production industry has grown exponentially on the Melbourne fringe over the past ten years. There are over 400 vineyards in Victoria and a large number of these properties are situated in the Yarra Valley and Mornington Peninsula within 50km of the Melbourne CBD. One major waste product from wine production is a material called grape marc which is a mixture of grape skins, grape seed and branchlets generated when grape juice is extracted from the freshly picked fruit. Grape marc is a potential biological hazard as it may contain disease such as phylloxera18. It is also quite acidic which may pose problems if the material is disposed of on land as mulch, which is common practice both in Australia and overseas. Grape marc is also reused as animal feed and some cases it is simply disposed of in landfill. Samples of this waste stream were obtained from a local vineyard and analysed for nutritive value. The results of this analysis are provided in Table 18 below.

18 Biala J., (2000) The use of composted organic waste in viticulture – A review of the international literature and experience The Organic Force – Environment Australia Sustainable Industries Branch Canberra Wynnum Queensland

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Table 18 Analysis of typical grape marc sample from a Victorian vineyard

*All results are expressed on a 40 C dry weight basis The results of this study showed that grape marc had high nutritive value (particularly as a source of K and P) and was suited for recycling. This waste stream should be investigated for treatment by windrow composting and conversion into compost suitable for use as a soil conditioner in the viticulture industry possibly by blending with another waste stream generated in the same region. Based on the current level of knowledge pertaining to compost use in European and North American vineyards, some of the positive effects of compost application include: (1) Supply of humus, (2) Supply of plant nutrients, and (3) Improvement of soil physical, chemical and biological properties. Potential negative effects include: (1) Oversupply of nutrients (particularly Nitrogen and Phosphorus, which can lead to excessive canopy growth and also be detrimental to the surrounding environment), and (2) Heavy Metals. So far the effects of compost on grape yields has been variable between trials due to differences in composts (dependent on choice of feedstock), vineyard soil, the control being used and the duration of the trial. In contrast to the numerous trials being conducted in overseas vineyards, minimal research has been conducted to date in Australia apart from a trial in South Australia 19 and another smaller trial in Victoria20. Economics has so far governed the lack of research into the use of compost in Australian vineyards. Nevertheless it’s benefits with respect to weed management, fertiliser capabilities and use as a water management tool are becoming increasingly evident from the trials being conducted in SA vineyards. Although composting could provide a safe and effective treatment process for grape marc other alternatives should also be investigated such as extraction of grape seed oil, which is very valuable material. However, the cost of establishing grape seed oil extraction facilities may make such an operation unviable. The results of this small survey into wastes generated in wine production has demonstrated that:

grape marc is a large and potentially recyclable waste stream generated in wine production

grape marc has high nutritive value and could be converted into a soil conditioner / fertiliser by composting with other waste streams

grape marc has the potential to be used to extract grape seed oil

19 Pankhurst C E., Hawke B G., McDonald H J., Kirkby C A., Buckerfield J C., Michelsen P., O’Brien K A., Gupta V S R., and Boube B M., (1995) Evaluation of soil biological properties as potential bioindicators of soil health Australian Journal of Experimental Agriculture 35: 1015-28.

20 Wilkinson K., Tymms S., Hood V., Tee E., and Porter I., (2000) Green Organics: risks, best practice and use in horticulture, A report on the IHD green organics research program, 1995-1999 Institute for Horticultural Development, Knoxfield, Victoria.

Element Unit Level * Na mg/kg 520 C: N ratio 21 N %w/w 2.2 C %w/w 47 P mg/kg 2500 K mg/kg 27000 S mg/kg 1400 Ca mg/kg 4300 Mg mg/kg 1000

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Food processing As stated previously, food processing is a very large industry in the Melbourne –Metropolitan area and produces large quantities of putrescible wastes. The tables below list a number of waste streams identified in the survey and their fate. In two cases the waste stream was sampled and analysed to assess its suitability for recycling. The waste volumes listed are for one company or facility only and were provided by company sources. Samples of waste streams from a number of these operations were taken and assessed for nutritive value. The results of these analyses are provided in Tables 20 and 21. Oats husks showed potential as a bulking agent in composting and were analysed specifically for major nutrients. Table 19 Miscellaneous waste streams identified in the Melbourne region generated in the food production industry (each example is information obtained from one facility only)

Type of operation Wastes Fate Jams, spreads and preserves

Yeast residue (Liquid) 3.6 ML per year

Piggery feed

Peanut butter 45 tonnes per year

Stock feed / landfill

Vegemite 45 tonne per year

Stock feed / landfill

Mayonnaise 30 kL per year

Stock feed / liquid waste handlers

Dressings 40kL per year


Jams 3kL per year


Canned vegetables Baked beans, spaghetti etc (38 tonne per week)

Landfill, vermiculture, composting

Frozen snack food production (Asian Foods)

Cabbage

Landfill

Potato chipping Potato peel, scrap potato, sludge 48m^3 per week

Landfill, in-vessel composting

Health foods and cereal products (company not in Melbourne region)

Oats husks 15,000 tonnes per year

Landfill, land application, stock feed

Wholesale fruit and Vegetable Market

20,000 tonnes per year fruit and vegetable wastes

Composted

The survey has shown that there are significant potentially recyclable waste streams generated in the food processing industry in the Melbourne region. The wastes are generally free of contamination and would be suited to composting by blending with other waste streams. In some cases Vermiculture could be a suitable option and there is currently some interest in looking at this process to treat waste from canned vegetable production21. One waste that shows enormous potential is oats husks from cereal food production. This material has a high C: N ratio and some nutritive value (P 1000 mg/kg) and could be blended with moist higher nitrogen source wastes (sludges) in composting in view of its light texture and high moisture affinity. In one regional centre, some 8000 tonnes of this material (of a total of 15,000 tones produced annually from one company)

21 personal communication, Heinz-Watties Australia

25

are recycled untreated as mulch for domestic and agricultural applications22. The remainder is used as stock feed or landfilled. Table 20 Samples of food wastes analysed for nutritive value and contaminants from two food-manufacturing companies Industry Waste

Selected Nutrients % Selected Heavy Metals (mg / L)

N P K Cd Cr Cu Co Pb Zn As Hg Baked Beans (One company)

0.93 0.06 <0.04 <1.0 <10 <1.0 <0.001 <10 0.009 <0.1 0.03

Potato Waste (One company)

0.12 <0.06 0.18 <1.0 <10 <0.001 <0.001 <10 <0.001 <0.1 0.04

* Each analyte has been calculated on a wet weight basis. Table 21 Analytical results for oats husks wastes from cereal food production. *All results are expressed on a 40 C dry weight basis

1.8 Overall findings of the survey This report has summarised the results of a survey conducted in the Melbourne – Metropolitan area to: survey and classify waste streams from a number of agri-industry activities in the

Melbourne/Metropolitan region according to nature, volume and potential for re-use,

chemically and physically characterise a range of raw wastes to determine their suitability as agricultural and other resources.

The first part of the survey was conducted on data supplied by the Victorian Environment Protection Authority (EPA) which consisted of a list of prescribed transported putrescible (biodegradable) wastes recorded in the Melbourne region from January to December 1997 that were being transferred to landfills or being applied to land. This was the most recent documented information on prescribed putrescible waste available at the time of initiating the study. The data was supplied as uncollated transport events identifying the general waste type, volume (or weight in certain cases), postcode of

22 personal communication ‘Moisture Mulch’ supplier, Rutherglen Victoria

Element Unit Level * Na mg/kg 300 C: N ratio 72 N %w/w 0.64 C %w/w 46 P mg/kg 1000 K mg/kg 7200 S mg/kg 610 Ca mg/kg 530 Mg mg/kg 640

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source, type of disposal, transporter and date of movement. On the basis of this information, a number of companies were contacted to investigate specific types of wastes produced and obtain samples for analysis and assessment. The second part of the survey involved collection of anecdotal data based on information obtained from Agriculture Victoria, several major waste management companies, commercial composters and various industry sources (telephone and in-person interviews). A number of non-prescribed waste streams were identified in this survey and information obtained regarding nature and reuse potential. Some of these wastes were sampled and analysed for nutritive value and contaminants. The survey has shown that available EPA data on putrescible waste streams in the Melbourne – Metropolitan area only reveals a small fraction of the potentially reusable putrescible wastes that are disposed of in landfills. Many waste streams were identified and characterised and found to be suited to treatment technologies such as composting. The Melbourne region generates huge volumes of green wastes from domestic and municipal council sources (approximately 0.5 million tonnes per year) and these are composted under Australian Standards at several facilities around Melbourne. These operations could be effectively utilised to treat clean putrescible wastes by incorporation into the composting process (as demonstrated in two studies carried out by the investigators in this project). In the Melbourne and Metropolitan region, there are several high value agricultural enterprises (eg. Vineyards, Vegetable production, Turf grass industry, Cut flower industry, Ornamental nursery industry, etc) which can potentially utilise these wastes in their direct form or after pre-treatment for their nutrient or soil ameliorant value. The major findings of the survey are listed below. The specific findings for each industry investigated are indicated. Wool scouring large volumes of wool scour sludges relatively free of contamination are disposed of in landfills in

the Melbourne region each year particularly in the latter part of the year the majority of wool scour sludges that are generated are not reused in any way (land disposal of

untreated sludge would appear to be only a short term option and could pose environmental problems such as surface water pollution, odour, groundwater contamination)







subsequent reduction of disposal costs and environmental impact

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Tanneries large volumes of tannery sludges and partly hydrolysed hair wastes are disposed of in landfills in









waste stream has potential for bioremediation tannery hair was found to be high in nitrogen and the chromium levels detected in the sample were

well below the ARMCANZ guidelines and consequently this material has great potential for reuse as a nitrogen source











be established to optimise the waste loading

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chicken litter is a huge waste stream which is almost completely recycled into the horticultural production industry

there is an urgent need to develop guidelines for the composting and appropriate application rates








potential for reuse due to high nutritive value potato wastes produced in the potato chipping industry consist of peelings, whole potatoes, potato

pieces, dirt and sludges Vermiculture should be investigated as a suitable option for disposal of some wastes streams in

food processing oats husks from cereal food production has a high C: N ratio and some nutritive value (P 1000

mg/kg) and could be blended with moist higher nitrogen source wastes (sludges) in composting in view of its light texture and high moisture affinity.







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2. Waste Remediation Studies 2.1 Composting Composting is a controlled biological breakdown of organic materials by microorganisms (mainly bacteria and fungi). In aerobic thermophilic composting the microorganisms transform the organic materials into valuable product. In recent times many factors have led to an increase in aerobic thermophilic composting. These factors include appeal, siting and regulatory concerns associated with landfills, improved technologies, volume reduction and revenue potential (Miller et al,1992). Composting can be particularly effective in converting wet materials to a more usable or easily disposable form. At the same time, composting can stabilise putrescible organics, destroy pathogenic organisms and provide significant drying of wet substrate. A large variety of wastes from food processing and agricultural industries are suitable for composting. Some of the food and agricultural wastes that have been successfully composted include abattoir wastes, hair waste, culled potatos (bruised, too small to use), potato skins (Haug et al, 1993) On the basis of the chemical analysis of the waste streams investigated in this study, and the close proximity of these waste streams to a composting facility located in Dandenong, cut flower wastes and potato wastes were selected for further investigation. The strategy adopted was to investigate streaming of these wastes into a commercial green-waste composting operation and to determine the optimal loading of the waste to effect remediation. In the case of cut flower wastes, the focus of the investigation was to destroy pesticides in the waste by the composting process. This required that the compost windrow be maintained at a sufficiently high temperature over an extended time to ensure complete decomposition of these contaminants. In the case of potato waste, the material was relatively free of contamination and was a potential source of water containing approximately 90% water by weight (refer to Appendix 1.7). As cadmium is frequently a contaminant in potatoes (only detected in the soil component of the wastes sampled), composting by blending into a green-waste stream had the advantage of eliminating the waste as well as reducing any cadmium contamination by dilution to acceptable levels (refer to Appendix 1.7). In both cases there was the potential to divert easily compostable wastes from landfill and at the same time produce a material that could be used in horticultural or agricultural production. 2.2 Composting Trials Three pilot-scale trials were conducted at a composting facility located in Dandenong. The first two of these trails involved small-scale remediation of cut flower wastes by blending with domestic green-waste. The third trial involved a commercial scale experiment in which a composite potato waste was blended with domestic green-waste and composted under normal operating conditions at the composting facility. 2.3 Composting Trial 1- Remediation of Cut flower wastes A typical waste that was identified in this study and having potential for re-use, was the off-cuts and waste from the flower growing industry. These wastes have already been described in the previous section of this report. Based on preliminary chemical analysis, it was found that there was no significant nutritive value in these wastes or heavy metal contamination, however, it was established that the wastes were contaminated with pesticides that are extensively used in this industry to guard against disease and insect infestation.

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2.3.1 Preliminary Screening of Wastes The chemical additives used by two of the participating farms in this study are listed in Table 22 A combined waste sample from these growers was analysed for chemical contamination, with several common pesticides being identified Table 23 (Meehan et al RIRDC Progress Report 1999). Table 22 List of Chemical additives used by Cut flower companies 1998

Chemical Name Brand Name Pesticides used by Farm No.1 Farm No.2 Agral X Avid X Nylate (NB: Br&Cl anti bac) X Abamectin Vertimec X Benomyl Benlate X Bitertanol Baycor X Bufenpyrad X X Tebufenpyrad Pyranica X X Captan Orthocide X Carbendazim Baviston X Chlorothalonil Bravo Plus X Cyproconazola Alto X Dicloran Diclorsan X Fenarimol Rubigan X Fluvalinate (D isomer) Mavrik X Fluzainam Shirlan X X Iprodione Rovral Aquaflow X X Maneozelo Dithane X Metalaxyl Ridomil Plus X Methamidophos Nitofol X Methomyl Lannate X Omethoate Folimat; Le-matt X X Oxycarboxin Plantvax X Permethrin Ambush X X Phosphorous Acid Fungex X Primicarb X X Prochloraz Octave X Propargite Omite X

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Table 23 Preliminary analysis of pesticides being used at time of sampling in cut flower waste from two different flower farms 1998

Concentration Pesticide Unit Farm No.1 Farm No.2 Captan mg/kg 0.56 <0.02 Dimethoate mg/kg 0.05 <0.05 Omethoate mg/kg <0.05 0.42 Permethrin mg/kg 0.18 0.23 Britertanol mg/kg <0.2 <0.2 Chorothalonil mg/kg 0.48 0.64 Iprodione mg/kg 0.91 4.10 Primicarb mg/kg <0.05 <0.05 Bufenpyrad mg/kg 0.10 <0.05

Note:<n.nn result denotes concentration. 2.3.2 Methodology 2.3.2.1 Collection and Transportation of Waste A waste management company was employed to deliver 11m3-15m3 bins to each of the flower producers. The flower waste collection was carried in late March to early April. After a period of 2 weeks the waste contents were transferred to the composting site at MulchMaster Pty Ltd a composting company in the nearby suburb of Dandenong. A total volume of approximately 12m3

was collected. The company’s main operation is to produce compost and mulch from different types of organic waste materials such as bark and waste timber, tree prunings and grass clippings from domestic street collection and local council operations. Refer to Appendix 3.1 for the site plan of the facility including the location of the trial site. 2.3.2.2 Windrow Design and Construction The layout and construction of the windrows was designed in consultation with the environmental engineer at MulchMaster. The dimensions (refer to Table 24.) were constructed in a way that would provide adequate surface area for composting, accommodate heavy machinery and equipment to access the windrows and to prevent obstruction with existing site operations. Table 24 Windrow Dimensions for each Treatment.

Dimensions (m) Volume (m3) Treatment l w h Total Volume (m3) Cut Flower Mulch Control 12 1.5 2.0 36 0 36.0 10% 10 1.0 1.5 15 1.5 13.5 20% 10 1.0 1.5 15 3.0 7.5 50% 10 1.0 1.5 15 7.5 7.5

The cut flower wastes collected from the three participating producers were thoroughly homogenised. A total of four windrows were constructed, one windrow was made of shredded domestic green-waste; this was used as a control to determine whether the addition of cut flowers had a significant effect on the composting process. The other three windrows contained a large proportion of shredded domestic green-waste and a smaller proportion of cut flower waste. The contents of each windrow are described in Table 25 below. In each of the windrows, a predetermined volume of shredded domestic green-waste was removed and replaced by an equal volume of cut flower waste, so that each windrow had a total volume of 15m3. All treatments were blended using a front-end loader to homogenise the material. A diagram of the composting site and also the location of the trial windrows are presented in Appendices 3.1 and 3.2

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Table 25 Description of Applied Treatments Treatment Description 1. Control Shredded domestic green-waste 2. 10% 10% of shredded domestic waste replaced by cut flower 3. 20% 20% of shredded domestic waste replaced by cut flower 4. 50% 50% of shredded domestic waste replaced by cut flower

2.3.2.3 Monitoring Program The windrows were regularly monitored for temperature over the entire duration of the study. Samples were also regularly taken for off-site analysis (pH, EC, and %Moisture). Over a period of 107 days, the core temperature and surface temperature of each windrow was measured as described in Appendix 3. Temperatures were recorded three times per week during the first three weeks of composting. In weeks four through to week 16, measurements were taken once a week. The readings were made at 5 equidistant positions along the length of the windrow; three readings were then taken at each position as shown in Appendix 3.3. During the composting process the windrows were turned every two to three days during the initial stages of composting. Turning then occurred once a week to limit the loss of heat, and allow pasteurization processes to occur. This process ensured that each windrow was being uniformly decomposed, that interstices were being reconstructed, and exhausted supplies of oxygen were renewed. 2.3.3 Results and Discussion 2.3.3.1 Effect of Cut Flowers on Average Core Temperature A composting mass is considered sanitised if it is maintained at 550C minimum of 3 consecutive days, or equivalent (AS445-1999). Some composting operators choose to employ higher temperatures to ensure the cooler zones in the compost mass reach the required 550C for the prescribed time (AS4454-1999 p43). Higher temperatures may be favourable to pathogen reduction, but not to an optimal rate of composting. Higher temperatures are also likely to favour destruction of organic contaminants such as the pesticides present in the wastes involved in this study. The average values for the core temperature of each windrow on each sampling event were calculated and plotted for 10%, 20% and 50% treatments against the average core temperature of the control windrow (Figures 9-11). This was carried out to monitor the composting process to determine if the incorporation of cut flowers had an effect on the windrow core temperature. The optimal temperature range for composting is 50-550C. An ANOVA analysis was performed to see if the introduction of cut flower waste had a statistically significant effect on the windrow core temperature (Appendix 3.4).

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Figure 9 Comparison between Average Core Temperature of Control & 10% Treatment.

Figure 10 Comparison between Average Core Temperature of Control & 20% Treatment

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M E AN [ 0 % C u t F lo w e rs ]M E AN [2 0 % C u t F lo w e rs ]O p tim u m (m in )O p tim u m (m a x)

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Figure 11 Comparison between Average Core Temperature of Control & 50% Treatment The core temperature of 10%, and 20% treatments reached 550C or higher at some stage during the composting process. These three composts therefore were adequately sanitised during the composting process. The average core temperature for the 50% treatment ranged between 30-550C, during the entire composting period. Despite reaching a temperature of 550C, the core temperature of the windrow was not maintained for 3 consecutive days. Therefore, all pathogens and weed seeds were probably not effectively destroyed during composting, which could pose problems if the product is to be used as a soil ameliorant. Overall, cut flower composted with shredded domestic green-waste caused a reduction in average core temperatures in each windrow. Based on statistical analysis (refer to Appendix 3.4), the average core temperature of the control was higher than the average core temperature of the 10%, 20% and 50% treatments. This difference equates to less microbial activity and consequent slower rate of decomposition. Each composted product with the exception of 50% treatment reached optimal temperatures, which means the materials were adequately sanitized and therefore safe to use. 2.3.3.2 Composted Cut flower Waste At the end of the composting period representative samples of each windrow were obtained by removing approximately 2.5L of composted materials from five positions along the length of the windrow. These positions were located at the core and approximately half way between the top and base of the windrow. The samples were combined, mixed thoroughly and then sub-sampled. These samples were subsequently tested in accordance with Standards AS4454-1999 for Composts, Soil Conditioners and Mulches to ensure that the composted materials were suitable for agricultural or horticultural application. The results of these analyses are presented in Table 26. According to the current Australian Standard for Composts, Soil Conditioners, and Mulches, the optimal pH range for composted products is 5.0 – 7.5. The results indicate that the pH of the control and three pasteurized composts containing cut flowers, are greater than 7.5. Since all three composts had a pH in excess of 7.5 this indicates that the elevated pH is due to the composting process rather than to the addition of cut flowers. The Australian Standard requires that compost with a pH in excess of 7.5 be further analysed for calcium carbonate content if the composted material is to be used as a soil conditioner. All four composted materials had CaCO3 levels in the vicinity of 5% by weight. The addition of cut flower wastes did have a small effect on the % carbon and C:N ratio. In the case of the 50% cut flower compost, the % carbon was approximately 5% higher than the control with a corresponding increase in the C:N ration from 22 to 26. In a commercial operation, this would need to be lowered by the use of a nitrogenous additive to bring the material in line with the Australian

5 0 % T r e a t m e n t V s . C o n t r o l

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 1 1 0 1 1 1 1D a y s

Tem

pera

ture

(C)

M E A N [ 0 % C u t F l o w e r s ]M E A N [5 0 % C u t F l o w e r s ]O p ti m u m ( m i n )O p ti m u m ( m a x)

35

Standard for a composted soil additive. This could possibly be achieved using another waste containing n such as tannery hair waste. The end product was also analysed for pesticide residues. Only the most persistent pesticides were selected for analysis. Selection of these analytes was carried out in consultation with staff from the Organic Chemistry Unit of the State Chemistry Laboratory. The results for the analysis of the two most concentrated treatments are presented in Table 27 The compost containing 10% cut flower waste was not analysed for pesticide residues, which if present would be more readily detected in the treatments containing a greater proportion of cut flower waste. This also helped to reduce analytical costs. Table 26 Chemical Characteristics of composted products as compared to AS4454 –1999.

% Cut Flower Waste : % Shredded Domestic Green Waste Parameter AS4454a 0 : 100 10 : 90 20 : 80 50 : 50 pH 5.0 – 7.5

If pH > 7.5 determine total CaCO3

8.12 ± 0.05 8.81 ± 0.03 8.63 ± 0.05 8.70 ± 0.04

Total CaCO3 %(w/w)

- 5.0 ± 0.5 5.0 ± 0.1 4.5 ± 0.1 4.7 ± 0.1

Electrical Conductivity (dS/m)

0 – 1b 0.617 ± 0.007 0.831 ± 0.007

0.486 ± 0.002 0.487 ± 0.003

Moisture % (w/w) ≥ 25 c 54 ± 2 52 ± 4 51 ± 4 60 ± 3

Organic matter content %dry matter

≥ 25 24 N/A N/A 29

Total N % dry matter

≥ 0.8 If a dry contribution to plant nutrition is claimed

1.1 N/A N/A 1.1

C:N ≤ 22 22 N/A N/A 26

Total P % (w/w) %dry mass

≤ 0.1 For products which claim to be for phosphorus - sensitive plants No requirement otherwise

0.010 ± 0.004 0.087 ± 0.006

0.031 ± 0.001 0.054 ± 0.007

Phosphorus, soluble (mg/L extract) mg/L extract

5 For products which claim to be for phosphorus- sensitive plants No requirement otherwise

4.0 ± 0.4 8.7 ± 0.6 3.1 ± 0.1 5.3 ± 0.6

a AS4454 –1999 Composts, Soil Conditioners and Mulches b Unlimited rate of application for plants that are sensitive and tolerant to salinity.

c If OM < 40% then maximum % Moisture = % organic

36

Table 27 Pesticide Analysis Results for composted samples of the Control, 20% Treatment and 50% Treatment [Pesticide]a mg/kg

Pesticide Control 20% 50%

Captan <0.01 <0.01 <0.01

Dichlran <0.01 <0.01 <0.01

Propargite <0.10 <0.10 <0.1

Methamidophos <0.05 <0.05 <0.05

Omethoate <0.05 <0.05 <0.05

Fluvalinate (Disomer) <0.05 <0.05 <0.05

Permethrin <0.05 <0.05 0.23

Where 0% = Control, 20% =flower compost, 50% flower compost a <n.nn result denotes concentration below the indicated limit of detection (LOD). The results from the pesticide analysis tabulated above indicate that most persistent pesticides used by the flower growing companies were successfully degraded during the composting process. The only exception was 50% treatment, which contained the highest concentration of cut flower waste. This is consistent with the core temperture data which showed that the windrow containing 50% cut flower waste had a temperature significantly lower then the control and did not achieve the optimal temperature condition of three consecutive days at 550C. Further, the core temperatures in all windrows was probably affected by the windrow dimensions employed and also the low ambient temperature during the trial (trial period from mid April to mid July). Overall the results of the study showed that green-waste contaminated with pesticides from a horticultural activity can be effectively remediated by streaming the waste into domestic green-waste composting operations. This process has the potential to be used to remediate similarly contaminated green-waste from other horticultural and agricultural production and result in composted materials that could be used as soil ameliorants or mulches. 2.3.4 Evaluation of Composted Material as a Potting Mix Component 2.3.4.1 Pot Trial The composted materials from the trial described above were subsequently evaluated as a substitute for a commercial growing medium. A pot trial was established in which the composted materials were mixed with washed river sand to produce four growing media. The pot trial was conducted in a temperature controlled Quarantine Glasshouse at one of the participating flower growers. Five treatments and six replicates were used in this trial. Table 28 describes each treatment. The Standard growing medium used was a commercially produced material. It contains 85% composted bark (mixture of fine [0-3mm], medium [3-5mm] and coarse [5-8mm] particles), 15% sand as well as lime, ammonium nitrate, and water retention granules. Each of the composted products had equivalent amounts of fine river sand added to them to become treatments A-D. Treatment F was made from the standard growing medium. Pots were filled to within 2cm of the top and 5 g of a slow release complete fertiliser added to each pot in accordance with standard procedures at the farm. Two different plants were used; Lebanese Cucumbers (grown from seed) and carnations (grown from seedlings). Lebanese cucumbers were chosen because they are known to be very sensitive to pathogens and diseases, The carnations on the other hand were selected to assess the effect of each treatment on the growth of ornamental flowers. The growers routinely use both species as indicator plants for pathogens (communication, G.Guy 1999).

37

The pots were positioned using a Latin square design. This ensured there would be no variation between plants across the house due to light differences and along the house due to temperature differences. Table 28 Treatments used in Pot Trial TREATMENT #POT DESCRIPTION A 6 100% Mulch : 0% Cut flowers +fertiliser B 6 90% Mulch : 10% Cut flowers +fertiliser C 6 80% Mulch : 20% Cut flowers +fertiliser D 6 50% Mulch : 50% Cut flowers +fertiliser F 6 Standard Growing medium +fertiliser

The dry weight data for the tops of carnation and cucumber plants were determined by drying harvested plant material at 65oC. The results were analysed by ANOVA analysis and are presented in Appendix 3.5. The results of the ANOVA analysis show that treatments A, B, C, D, and F all have the same average effect on the dry weight of carnations and cucumbers. This was consistent with the visual appearance of the plants that showed no obvious differences in size or indication of disease such as chlorosis or necrosis on the leaves. The results therefore demonstrate that composts prepared from wastes generated by the flower producer could be reused on-site as an inexpensive substitute for commercial growing media. However, in view of the possible introduction of pathogens into the system by the use of these materials, it is clearly very important that the composts be prepared strictly according to the Australian Standard AS4454-1999. 2.3.5 Summary of findings Overall, the investigation has shown that composting has the potential to remediate cut flower wastes generated in flower production. The significant outcomes were: cut-flower waste could be effectively diverted from landfill disposal by composting with

shredded domestic green-waste to produce a material that could be reused in horticultural or agricultural applications

persistent chemicals used in flower production were successfully degraded at rates below 50% cut flower incorporated into the green-waste

the composting process is potentially an effective means of destroying persistent chemical residues in vegetative waste materials from horticultural or agricultural activities

the materials produced in this process were demonstrated to be suitable for reuse either as a mulch or as a soil ameliorant / potting media component

2.4 Composting Trial 2 - Remediation of Cut flower wastes On the basis of the preliminary study into the bio-remediation of cut flower waste described above, most persistent pesticides used by the flower growing companies were successfully degraded during the composting process. The only exception was 50% treatment, which contained the highest concentration of cut flower waste. The core temperature data showed that the windrow containing 50% cut flower waste had a temperature significantly lower then the control and did not achieve the optimal temperature condition of three consecutive days at 550C. Further, the core temperatures in all windrows was probably affected by the windrow dimensions employed and also the low ambient temperature during the trial (trial period from mid April to mid July). A second trial was subsequently designed to run over warmer months to examine whether there was any significance differences in

38

replicated windrows using 50% cut flower compared to 100% green-waste. Clearly, if the strategy of incoproating contaminated plant materials into green-waste streams is to be viable, the loadings should be large enough to cope with the waste volumes and still be effective in remediating the waste. 2.4.1 Preliminary Screening of Cut flower Wastes Twenty samples of cut flower waste of equal volume (1L container) were removed from the homogenised heap at trial site-MulchMaster. The samples were subsequently combined to form one sample and submitted to State Chemistry Laboratory for pesticide analysis. The results of mean pesticide residues analysed in raw cut flower waste are presented in Table 29 Table 29 Pesticide residues analysed in cut flower waste April 2000

[Pesticide]a mg/kg

Pesticide Unit Mean Confidence Interval

Captan mg/kg 1.14 1.32

Dichlran mg/kg <0.01 0.01

Propargite mg/kg 0.9 0.38

Methamidophos mg/kg 0.15 0.11

Omethoate mg/kg <0.05 0.04

Fluvalinate (Disomer) mg/kg <0.05 0.04

Permethrin mg/kg 0.26 0.13

*Results are reported as received basis Note: <n.nn result denotes concentration below the indicated limit of detection (LOD) The preliminary screening results indicate that there are significant persistent pesticide residues existing in the cut flower waste, especially Captan, Propargite and Permethrin. The result demonstrates the importance of effective remediation methods if these materials are to be reused in land applications. 2.4.2 Methodology 2.4.2.1 Collection and Transportation of Waste Waste flowers were deposited in an open location at the rear of the farm (F&I Baguley Flower & Plant Growers) to allow easy access for collection and removal. The flower waste collection was carried out in mid-February to early March. After a period of approximately 3 weeks, the wastes were transferred to the same composting site used in the first remediation trial. A total volume of approximately 24m3

was collected. The wastes again consisted of discarded flowers, off-cuts and foliage from harvested flower crops. The actual total volume of waste material collected was more likely around 50m3 as the materials tended to shrink noticeably in the warm conditions. 2.4.2.2 Windrow Design and Construction The windrow design and construction were based on the following criteria: availability of space at trial site, principals of effective conditions for composting (eg size and dimensions), easy access of machinery and equipment and siting such that the experiment did not interfere with existing site operations. Some composting researchers report that the shape of the windrow should be 1.5-3.0m high and 2.4-5.0m wide with a round shaped top (Horstman,O. et al,1961 and Haug, 1993). On the basis of these reports, and consultation with the plant operator at MulchMaster (Communication G.Higgs) the

39

dimensions presented in Table 30 were employed. The cut flower waste was thoroughly homogenised prior to windrow construction using a front- end loader. A total of six windrows were constructed; three windrows contained 100% green-waste and the other three contained a mixture of 50% cut flower waste and green-waste (refer to Appendix 4 for windrow layout and monitoring positions). Table 30 Windrow dimensions for each treatment

Dimensions (m) Volume (m3) Treatment l w h

Total Volume (m3) Cut Flower Mulch

Control Rep1 4 2 2 16 0 16 Control Rep2 4 2 2 16 0 16 Control Rep3 4 2 2 16 0 16 50%Cut flower Rep1 4 2 2 16 8 8 50%Cut flower Rep2 4 2 2 16 8 8 50%Cut flower Rep3 4 2 2 16 8 8

2.4.2.3 Monitoring Program A monitoring program was established for the composting process in accordance with AS4454-1999 and the ‘Guide to Best Practice Composting’ to ensure that composting was performed at optimal conditions. The core and surface temperatures were recorded at 5 equidistant positions along the length of each windrow on a regular basis using a HM141 Humidity and Temperature Indicator connected to a HMP46 probe (refer to Appendix 4.3). Temperature measurements were taken regularly over the 102 days of the trial. Core samples were collected on each of these occasions and the compost analysed for pH, conductivity and moisture content according to AS4454-1999. During the composting process the windrows were turned every two days during the initial stages of composting. Turning then occurred once a week to limit heat loss and allow pasteurisation processes to occur. 2.4.3 Results and Discussion 2.4.3.1 Effect of Cut Flowers on Average Core Temperature The average core temperatures were plotted for 50% treatment and the core temperature for the control. (Figure 12 and 13 respectively). An ANOVA analysis was subsequently performed to determine if the introduction of cut flower waste had a statistically significant effect on core temperature during the composting process (refer to Appendix 4.5).

40

Figure 12 Comparison between Average Core Temperature of Control replications Figure 13 Comparison between Average Core Temperature of 50% Treatment replications The average core temperature of the control and 50% treatment fluctuated between 400C and 700C during the entire composting period. The lower temperatures probably being caused by turning shortly before measurement. On the basis of the ANOVA analysis it was found that there was no significant difference between the control and the 50% treatment windrows (P<0.05). There was also no significant differences (P<0.05) between control and 50% cut flower compost with respect to pH, or conductivity, further indicating that the incorporation of the cut flowers had no effect on the green-waste composting. These observations are consistent with this trial being carried out under higher ambient conditions that caused the wastes to dry out considerably prior to composting. In the previous trial, the wastes were collected in autumn and were quite moist when mixed into the green-waste. The composting process in this earlier trial was also conducted through the winter months and the small dimensions of the windrows together with low ambient temperatures were not conducive to effective composting. This observation indicates that effective remediation of these wastes is affected by the original moisture content of the waste and that composting in cooler months of the year requires lower waste loadings in the windrow or pre-drying of the wastes before incorporation into the green-waste.

ControlReplication1 vs Replication2 vs Replication3

0.0010.0020.0030.0040.0050.0060.0070.0080.00

0 20 40 60 80 100 120Days

Tem

pera

ture

C

Replicate1 Replicate2 Replicate3

50% TreatmentReplicate1 vs Replicate2 vs Replicate3

0.0010.0020.0030.0040.0050.0060.0070.0080.00

0 20 40 60 80 100 120

Days

Tem

pera

ture

C

Replicate1 Replicate2 Replicate3

41

The previous trial indicated that a loading of moist cut flower waste in cooler months should be between 20 and 50 % to effect remediation. 2.4.3.2 Composted Cut Flower Waste At the conclusion of the composting trial (102days), representitive core samples of each windrow were obtained by removing approximately 2L of composted materials from five positions along the east and west sides of the windrow and top. These position are located described in (Appendix 4.3) . The core samples were bulked to form a representative sample of the windrows and were subsequently tested in accordance with Standards AS44554-1999 for Composts, Soil Conditioners and Mulches to ensure that the composted materials were suitable for agricultural or horticultural application. The results of these analyses are presented in Table 31. According to the 1999 Australian Standard for Composts, Soil Conditioners, and Mulches, the optimal pH range for composted products is 5.0-7.5. The results indicate the pH of the all replicated control and treatments containing cut flowers are greater then 7.5. The Australian Standard requires that compost with a pH in excess of 7.5 be further analysed for calcium carbonate content if the composted material is to be used as a soil conditioner. Both the 50% and control composts had CaCO3 levels in the vicinity of 5% by weight. The addition of cut flower wastes did have a small effect on the % carbon and C: N ratio. In a commercial operation, this would need to be lowered by the use of a nitrogenous additive to bring the material in line with the Australian Standard for a composted soil additive. As stated previously, this could possibly be achieved using another waste containing N such as tannery hair waste. These samples were also analysed for pesticides known to be present in the original waste (refer to Table 32). The results of pesticide residue analysis showed that the selected persistent pesticides used by the flower growing companies were successfully degraded during the composting process. The results of this replicated trial are not consistent with the preliminary trial described previously in that cut flower waste blended at a rate of 50% with domestic green-waste was effectively composted and all pesticides were destroyed in the process. This trial was carried out over warmer months of the year and the waste had dried out considerably when mixed with the green-waste. This probably contributed to the higher temperatures achieved in this trial and subsequent improved composting conditions.

42

Table 31 Chemical Characteristics of composted products compared to as 4454 –1999

%Cut flower : %Green-waste Parameter AS4454a 0 : 100 50 : 50 pH 5.0 – 7.5

If pH > 7.5 determine total CaCO3

8.10 ± 0.3 8.53 ± 0.1

Total CaCO3 % (w/w) - 5.0 ± 0.5 4.3 ± 0.1 Electrical Conductivity (dS/m) 0 – 1b 1.8 ± 0.3 2.2 ± 0. 2 Moisture % (w/w) ≥ 25 c 62 ± 2 54 ± 3

Organic matter content %dry matter

≥ 25 24 ± 2 29 ± 2

Total N %dry matter

≥ 0.8 If a dry contribution to plant nutrition is claimed

1.1 ± 0.2 1.1 ± 0.2

C:N ≤ 22 22 26

Total P % (w/w) %dry mass

≤ 0.1 For products which claim to be for phosphorus - sensitive plants No requirement otherwise

0.08 ± 0.004 0.050± 0.006

Phosphorus, soluble (mg/L extract) mg/L extract

5 For products which claim to be for phosphorus- sensitive plants No requirement otherwise

4.0 ± 0.4 5.8 ± 0.5

a AS4454 –1999 Composts, Soil Conditioners and Mulches b Unlimited rate of application for plants that are sensitive and tolerant to salinity. c If OM < 40% then maximum % Moisture = % organic

Table 32 Pesticides analysed in 50%composted cut flower waste June 2000

[Pesticide]a mg/kg

Pesticide Unit Replication 1 Replication 2 Replication 3

Captan mg/kg <0.01 <0.01 <0.01

Dichlran mg/kg <0.01 <0.01 <0.01

Propargite mg/kg <0.01 <0.01 <0.01

Methamidophos mg/kg <0.05 <0.05 <0.05

Omethoate mg/kg <0.05 <0.05 <0.05

Fluvalinate (Disomer) mg/kg <0.05 <0.05 <0.05

Permethrin mg/kg <0.05 <0.05 <0.05

*Results are reported as received basis Note: <n.nn result denotes concentration below the indicated limit of detection (LOD) According to the second cut flower compost trial, chemical analysis showed a significant reduction in biocide residues for the 50%cut flower waste. Preliminary estimates of savings show that an individual farm could potentially reduce waste disposal and potting media costs by up to 70% (communication G.Guy).

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2.4.4 Summary of Findings The results of this second replicated trial using green-waste to compost contaminated cut flower waste clearly demonstrate the effectiveness of composting as a means of remediating this waste. The key outcomes of the study were: cut flower wastes can effectively be combined at a rate of 50% into a green-waste composting





2.5 Composting Trial 3 - Potato Scraps Wastes It was estimated that 25 tonnes of potato scraps and peelings were produced in one company per week during the potato chipping process. During the preparation stage, where potatoes are cleaned and skinned prior to chipping, whole potatoes are passed through conveyers to be washed, shaved then sliced before conversion into crisp chips. The wastes that are generated through this process include whole potatoes, potato scraps, peelings, dirt and potato sludge. The waste material that was of interest in this study is the high moisture content potato scraps and peelings. Chemical analysis previously carried out showed that this waste was free of contamination and as it has such a high water content, it is potentially a moisture source for the composting process. The strategy employed in this study was to blend potato wastes in with green-waste at a conservative level (approximately 20% by volume) to determine if the wastes could be effectively treated and not interfere with the composting process. Unlike the previous trials, this study was carried out on a commercial scale using full sized windrows. Plant operators have collected core temperature data for this trial on site since the trial began some 8 weeks ago. The trial is still in progress and the results reported in this document are for the first 7 weeks of monitoring. 2.5.1 Preliminary Screening of Potato Wastes The bulk of the potato waste was a composite of potato shavings, potato solids dirt. Twenty samples of equal volume (approximately 1 L) were removed from each stage in the process and submitted for chemical analysis. The chemical characteristics and physical nature of the potato wastes are tabulated below.

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Table 33 Characteristics of potato scraps and peelings 2000

Industry Waste Selected Nutrients (Unit) %w/w mg/kg N P K Cd Cr Cu Pb As Potato shavings 1.7 1200 16000 <0.5 <0.5 8 <10.0 0.056 Potato solids 1.6 1700 13000 <0.5 <0.5 4 <10.0 <0.05 Potato shavings & dirt 1.3 1800 11000 0.5 0.5 20 <10.0 1800

Test reported on a 400C dry weight basis Table 34 Analysis of %Moisture, pH, EC, C/N and Total N of waste from Potato Waste Units Potato Scraps Potato Solids Potato & Dirt

Moisture (400C) % w/w 90.3 75.3 70.8 pH [H2O] 5.8 6.2 5.8 EC dS/m 1.7 4.1 15.1 Total Sodium mg/kg 250 150 16000 Total Chloride % w/w 0.11 0.44 3.7 Total Nitrogen % w/w 1.7 1.6 1.3

*Results are expressed at 400C as dry weight basis The chemical results in the table above indicate that there is low level of contamination, especially cadmium that is known to accumulate in some potato varieties. Cadmium is the heavy metal of greatest concern, and caution must me taken in using soil ameliorants derived from potato waste as it may result in cadmium accumulation in soils. 2.5.2 Methodology 2.5.2.1 Collection and Transportation of Waste A Potato chips company located in the Melbourne suburb of Scoresby was approached to participate in the potato composting trial. The waste generated at the company consisted of shavings, potato pieces , whole potatoes and dirt mixed with shavings. The plant manager estimated that that in excess of 15 tonnes of potato peeling wastes alone were disposed of in a week from the site, however this varied depending on the season. Wastes were collected over a ten-day period after which the waste containers were transported to MulchMaster. On arrival the waste was homogenised using a front-end loader and subsequently blended in with green-waste from domestic street collections. 2.5.2.2 Windrow Design and Construction Four windrows 20 m long, 3m wide and 2m high were constructed from green-waste (Appendix 6.1). Two of the windrows were used as controls and the other two used to incorporate the potato waste. The centres of these two latter windrows were opened using a front-end loader and the potato waste added over the entire length. These windrows were then turned thoroughly to ensure a homogeneous mixture of the potato waste and green-waste. Approximately 40 tonnes of potato waste (a composite of all solid waste streams) was added to these two windrows representing a loading of 20% by volume. 2.5.2.3 Monitoring Program Core temperatures were recorded of each windrow at 10 locations along each side approximately 1 m from the base. The results to date were collated and ANOVA analysis carried out to assess the effect of adding potato wastes to the green-waste windrows (refer to Appendix 5.2). As the study is still in progress the data presented in this report is for the first 7 weeks of the experiment, however, this is

45

sufficient information to determine whether the technique is suitable for remediation of potato scrap waste. 2.5.2.4 Results and Discussion The average core temperature of the controls potato waste treatments fluctuated between 500C and 700C during the 7 week composting period. The lower temperatures being recorded on days immediately after turning . At the end of the 7 week period the mean core temperatures of the control and potato waste windrows were 66.250C and 64.900C respectively indicating that the composting process was still taking place and the core temperatures were at opitmal conditions for composting. The grand core temperature averages over the trial period were 66.680C and 64.610C respectively for the control and potato waste windrows. ANOVA analysis of mean core temperatures showed that there was a significant difference ( P<0.05) between these windrows over the trial period. The potato waste had the effect of cooling the windrows (approximately 20C below the control) but did not affect the composting process as the temperature was still well within the optimal range ( 550C – 650C). This is not unexpected as the potato waste has a high moisture content. Visual inspection of the widrows after 7 weeks showed that there were no visible signs of potato waste present and the control and treatment windrows were identical in appearance. The results of this trial indicate that even higher rates of potato waste could be incoporated into the windrow without affecting the composting process, but further work would need to be carried out to opitimise the loading. Preliminary estimates on potential savings (communication G.Higgs) show that disposal costs for these wastes streams could be reduced by up to 70% using the composting option described above. 2.5.3 Summary of Findings The results of this commercial scale trial appear to demonstrate the effectiveness of composting as a means of remediating potato wastes. The key outcomes of the study were: potato wastes can be remediated effectively and inexpensively by windrow composting with

green-waste

the high moisture content of the potato waste has a slight cooling effect on the windrow but does not affect the composting process when added at a rate of 20% by volume

higher rates of potato waste could be remediated by this technique but further trials

would need to be established to optimise the waste loading

46

3. Outputs 3.1 Major Findings of Survey of Putrescible Wastes in Victoria Wool scouring large volumes of wool scour sludges relatively free of contamination are disposed of in landfills in

the Melbourne region each year particularly in the latter part of the year the majority of wool scour sludges that are generated are not reused in any way (land disposal of

untreated sludge would appear to be only a short term option and could pose environmental problems such as surface water pollution, odour, groundwater contamination)







subsequent reduction of disposal costs and environmental impact Tanneries large volumes of tannery sludges and partly hydrolysed hair wastes are disposed of in landfills in









waste stream has potential for bioremediation

47

tannery hair was found to be high in nitrogen and the chromium levels detected in the sample were well below the ARMCANZ guidelines and consequently this material has great potential for reuse as a nitrogen source











be established to optimise the waste loading chicken litter is a huge waste stream which is almost completely recycled into the horticultural

production industry there is an urgent need to develop guidelines for the composting and appropriate application rates








potential for reuse due to high nutritive value potato wastes produced in the potato chipping industry consist of peelings, whole potatoes, potato

pieces, dirt and sludges

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Vermiculture should be investigated as a suitable option for disposal of some wastes streams in

food processing oats husks from cereal food production has a high C: N ratio and some nutritive value (P 1000

mg/kg) and could be blended with moist higher nitrogen source wastes (sludges) in composting in view of its light texture and high moisture affinity.







3.2 Major Findings of waste Remediation Trials Cut-Flower Wastes The results of the study using green-waste to compost contaminated cut flower waste clearly demonstrate the effectiveness of composting as a means of remediating this waste. The key findings of the study were: cut flower wastes can effectively be combined at a rate of 50% into a green-waste composting





49

Potato Processing Wastes The results of this commercial scale trial appear to demonstrate the effectiveness of composting as a means of remediating potato wastes. The key outcomes of the study were: potato wastes can be remediated effectively and inexpensively by windrow composting with

green-waste

the high moisture content of the potato waste has a slight cooling effect on the windrow but does not affect the composting process when added at a rate of 20% by volume

higher rates of potato waste could be remediated by this technique but further trials

would need to be established to optimise the waste loading presentation of the results of these studies at waste management conferences, workshops and

regular meetings of representatives of key agricultural research institutes in Victoria (The Resource Reuse and Recovery for Primary Industries Group)

An additional outcome from the project was the development of a number of undergraduate and post-graduate research investigations in the Applied Science and Engineering Faculties at RMIT University. These projects are funded by postgraduate research scholarships, University and Agriculture Victoria Resources.

These include:

final year Environmental Engineering Design projects in waste management strategies for Wool Combing and Cut flower production companies. (Projects supervised by Associate Professor Barry Meehan in conjunction with industry representatives) (refer to Appendix 6 for information)

an Honours project to investigate the bio-remediation of contaminated Cut flower waste using windrow composting. (Project supervised by Associate Professor Barry Meehan)

a doctoral research project on the utilisation of regional waste streams in viticulture was established in 2000 (Project supervised by Associate Professor Barry Meehan).

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4. Communications and Recommendations

Results of the present study have previously been communicated to RIRDC in progress reports and have also been communicated at several waste management conferences and work shops ( refer references)

It is recommended that further surveying needs to be carried out in regional Victoria as well as Metropolitan Melbourne in order to identify significant waste streams containing reusable organics that are not recorded as prescribed wastes. These materials could then be investigated for potential recovery and reuse in agricultural and horticultural operations. Various Metropolitan and Rural industries should fully explore the opportunities to convert high cost wastes into value added environmentally friendly by-products.

It is recommended that various Institutes of Agriculture Victoria should undertake applied Research and Development to characterise modify / manage and utilise agri-industry wastes produced in their respective regions with a view to facilitating regional waste management strategies for post-farmgate wastes ( this initiative is currently being developed by the recently formed Resource Reuse and Recycling for Primary Industries Group in Agriculture Victoria in conjunction with RMIT University)

Care must be taken to control any adverse effects from waste applications such as induced salinity and sodicity, nutrient imbalances, high BOD, contamination from organic residues and heavy metals which underlines the importance of thorough characterisation of waste streams before they are developed into value added products for land application.

Benefits for development of reuse and recycling strategies in post-farmgate wastes accrue to industry by reducing waste disposal costs and establishing an environmentally friendly image important for marketing products locally and overseas.

51

5. References Agri-Topic, (1997) Heavy Metals in Fertilizers and Agriculture, Publication 142, March Cameron, K. C., Di, H. J., and R. G. McLaren, Is Soil an Appropriate Dumping Ground for Our Wastes? , ASSSI and NZSSS National Soils Conference, July 1996. Graham Guy , Plant Pathologist Baguley’s Flower Growers, Personal Communication 1999 Garry Higgs, Composting Plant Supervisor, Personal Communication 1999 Meehan,B.J, Baxter,F., and Maheswaran.J, Progress Report RIRDC Project No. RMI-10A, Reuse Potential of Agri-Industry Wastes in the Melbourne/Metropolitan Region, June 1999 EPA Putrescible Waste Stream Data 1997. EPA Industrial Waste Strategy Zeroing in on Waste: Pathway to Cleaner Production in Victoria, April 1998 EPA Victoria (1996) Environmental Guidelines For Composting and Other Organic Recycling Facilities, Publication 508, June. Haug R.T., Compost Engineering: Principles and Practice, Ann Arbor Science Publishers, Inc. United States, 1980 Haug R.T., Compost Engineering: Principles and Practice, Ann Arbor Science Publishers, Inc. United States, 1993 Hitchens L and Kashmanian R.M., Composting: Programs, Process and production Landreth R.E. and Rebers P.A., (Editors) Municipal Solid Wastes- Problems and Solutions CRC Press, Inc. Boca Raton, Forida. 1997 Horstman,O. and Engelhorn,E. Does Aeration accelerate the Composting Process: Comprehensive Studies of Solid Waste Management, First and Second Annual Report 1970, Vol.1, pp.173 1961 Maheswaran, J., Peverill, J., SCL Milestone Report, The Investigation of the Potential for the Utilisation of Hair as Fertiliser and Soil Amendment, Product characterisation of waste material from the Victorian Hide and Skin Producers (State Chemistry Laboratory) 1998 Meehan,B.J., Baxter, F., and Jay Maheswaran, Progress Report RIRDC Project No RMI-10A, Re-use Potential of Agri-industry Wastes in the Melbourne/Metropolitan Region, November 1998. Meehan,B.J., Baxter,F., and Jay Maheswaran, Progress Report RIRDC Project No RMI-10A, Re-use Potential of Agri-industry Wastes in the Melbourne/Metropolitan Region, November 1999. Miller,P.A., and P.A Golden. Earth For Sale: Policy Issues in MSW Composting. New York Legislative Committee on Solid Waste Management. August. 1992 Pollution Technology Review No.12, Large Scale Composting, Noyles Data Corporation, United States, 1974 Standards Australia , Australian Standard AS4454- Composts, Soil conditioners and Mulches Standards Association of Australia, Homebush, NSW, 1999 Rechcigl, J.E., and H. C. MacKinnon, Agricultural Uses of By-Products and Wastes, American Chemical Society, 1997 Wilkinson K, Tymms S., Hood V., Tee E., Guide to best Practice: Composting Green Organics EcoRecycle Victoria, East Melbourne Vic, 1998

52

6. APPENDICES APPENDIX 1 Chemical Analysis of Waste Material 1999 The following pages tabulate concentrations of elements found in the preliminary screening of Wool Scour, Tannery, Cut flower and Food Processing Waste. The tests were all performed at State Chemistry Laboratory and received in August 1999.

53

APPENDIX 1.1 Wool Scouring Wastes- Company 1 Chemical Analysis of waste from Wool Scour Processor No.1 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste and Limits for contaminants in compost (Dry solids). 1999 Analyte Unit Wool

Sludge Dirt and Fibres

EPA limits Grade A

Dry solids

General Information Moisture loss – 400C % w/w 44.6 3.9 General Chemistry* Total Nitrogen % w/w 1.2 2.4 Total Phosphorus % w/w <0.06 <0.06 Total Potassium % w/w 0.58 1.5 Total Sulfur % w/w 0.07 0.34 Total Calcium % w/w 0.18 0.39 Total Magnesium % w/w 0.12 0.25 Total Sodium % w/w 0.04 0.12 Total Manganese % w/w 0.015 0.022 Total Iron % w/w 1.6 1.4 Total Boron % w/w 0.0005 <0.0003 Total Chloride % w/w 0.06 0.15 Total Molybdenum % w/w <0.001 <0.001 Heavy Metal Chemistry* Total Cadmium mg/kg <1.0 <1.0 3 3 Total Chromium mg/kg 26 15 100 50 Total Cobalt % w/w <0.001 <0.001 Total Copper % w/w <0.001 <0.001 100 60 Total Lead mg/kg <10.0 <10.0 150 150 Total Zinc mg/kg 0.007 0.008 200 200 Total Arsenic mg/kg 2.0 2.4 20 20 Total Mercury mg/kg 0.03 0.02 1 1

*Results are expressed on an as received basis Analysis of %Moisture, pH, EC, C/N and Total N of waste from Wool Scour Processors No.1. 1999 Units Wool Sludge Dirt and Fibres Moisture (400C) % w/w 44.6 3.9 pH [H2O] 7.7 6.9 EC dS/m 3.6 5.6 C/N [calc.] 7.2 8.3 Total Nitrogen % w/w 1.2 2.4

*Results are expressed on an as received basis

54

APPENDIX 1.2 Wool Scouring Wastes- Company 2 Chemical Analysis of waste from Wool Scour Processors No.2 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste and Limits for contaminants in compost (Dry solids). 1999 Analyte Unit Wool


EPA limits Grade A

Dry solids

General Information Moisture loss – 400C % w/w 30.4 9.3 General Chemistry* Total Nitrogen % w/w 0.54 3.9 Total Phosphorus % w/w <0.06 0.15 Total Potassium % w/w 0.61 2.5 Total Sulfur % w/w <0.05 0.44 Total Calcium % w/w 0.30 0.40 Total Magnesium % w/w 0.08 0.17 Total Sodium % w/w 0.03 0.18 Total Manganese % w/w 0.017 0.22 Total Iron % w/w 1.0 0.61 Total Boron % w/w <0.0003 <0.0003 Total Chloride % w/w <0.03 0.35 Total Molybdenum % w/w 0<0.001 0.002 Heavy Metal Chemistry*

Total Cadmium mg/kg <1.0 <1.0 3 3 Total Chromium mg/kg 28 <10 100 50 Total Cobalt % w/w <0.001 <0.001 Total Copper % w/w <0.001 <0.001 100 60 Total Lead mg/kg <10.0 <10.0 150 150 Total Zinc mg/kg 0.006 0.008 200 200 Total Arsenic mg/kg 2.0 2.6 20 20 Total Mercury mg/kg 0.01 0.03 1 1

*Results are expressed on an as received basis Analysis of %Moisture, pH, EC, C/N and Total N of waste from Wool Scour Processor No.2 1999 Units Wool Sludge Dirt and Fibres Moisture (400C) % w/w 30.4 9.3 pH [H2O] 8.3 8.1 EC dS/m 4.6 9.5 C/N [calc.] 10.2 8.5 Total Nitrogen % w/w 0.54 3.9


55

APPENDIX 1.3 Wool Scouring Wastes- Company 3 Chemical Analysis of waste from Wool Scour Processor No.3 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste and Limits for contaminants in compost (Dry solids). 1999 Analyte Unit Wool


EPA limits Grade A

Dry solids

General Information Moisture loss – 400C % w/w 43.5 62.8 General Chemistry* Total Nitrogen % w/w 0.48 1.5 Total Phosphorus % w/w <0.06 <0.06 Total Potassium % w/w 0.27 0.14 Total Sulfur % w/w 0.05 0.39 Total Calcium % w/w 0.24 0.15 Total Magnesium % w/w 0.09 0.03 Total Sodium % w/w 0.04 0.06 Total Manganese % w/w 0.014 0.010 Total Iron % w/w 1.1 0.48 Total Boron % w/w <0.0003 <0.0003 Total Chloride % w/w <0.03 <0.03 Total Molybdenum % w/w <0.001 <0.001 Heavy Metal Chemistry*

Total Cadmium mg/kg <1.0 <1.0 3 3 Total Chromium mg/kg 22 19 100 50 Total Cobalt % w/w <0.001 <0.001 Total Copper % w/w <0.001 0.002 100 60 Total Lead mg/kg <10.0 <10.0 150 150 Total Zinc mg/kg 0.007 0.007 200 200 Total Arsenic mg/kg 2.5 1.3 20 20 Total Mercury mg/kg 0.02 1 1

*Results are expressed on an as received basis Analysis of %Moisture, pH, EC, C/N and Total N of waste from Wool Scour Processors No.3. 1999 Units Wool Sludge Dirt and Fibres Moisture (400C) % w/w 43.5 62.8 pH [H2O] 8.5 9.9 EC dS/m 3.3 6.6 C/N [calc.] 6.7 7.0 Total Nitrogen % w/w 0.48 1.5


56

APPENDIX 1.4 Tannery Wastes- Company 1 Chemical Analysis of waste from Tannery No.1 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste 1999 Analyte Unit Tannery

Sludge (Cr)Tannery Sludge (Fatty)

Hair Fibres EPA limits Grade A

General Information Moisture loss – 400C % w/w 75.7 49.1 52.8 General Chemistry* Total Nitrogen % w/w 0.79 0.67 5.3 Total Phosphorus % w/w <<0.06 <0.06 <0.06 Total Potassium % w/w 0.11 <0.04 <0.04 Total Sulfur % w/w 0.95 0.19 1.4 Total Calcium % w/w 0.56 0.37 1.2 Total Magnesium % w/w 1.3 0.3 0.06 Total Sodium % w/w 0.53 0.44 0.48 Total Manganese % w/w 0.019 <0.001 0.002 Total Iron % w/w 0.39 0.088 0.015 Total Boron % w/w 0.085 0.0010 0.030 Total Chloride % w/w 2.9 Unfinish 0.75 Total Molybdenum % w/w <0.001 <0.001 <0.001 Heavy Metal Chemistry*

Total Cadmium mg/kg <1.0 <1.0 <1.0 3 Total Chromium mg/kg 64000 65 140 100 Total Cobalt % w/w 0.003 <0.001 <0.001 Total Copper % w/w 0.002 <0.001 <0.001 100 Total Lead mg/kg <10.0 <10.0 <10.0 150 Total Zinc mg/kg 0.088 0.002 0.009 200 Total Arsenic mg/kg 1.0 Unfinish 0.1 20 Total Mercury mg/kg 0.08 <10.0 0.07 1

*Results are expressed on an as received basis Analysis of %Moisture, pH, EC, C/N and Total N of waste from Tannery No.1 1999 Units Tannery Sludge

(Cr) Tannery Sludge (Fatty)

Hair Fibres

Moisture (400C) % w/w 75.7 49.1 52.8 pH [H2O] 7.7 8.0 9.8 EC dS/m 1.6 5.7 8.5 C/N [calc.] <0.06 <0.06 <0.06 Total Nitrogen % w/w 0.79 0.67 5.3


57

APPENDIX 1.5 Tannery Wastes - Company 2 Chemical Analysis of waste from Tannery No.2 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste and Limits for contaminants in compost (Dry solids). 1999 Analyte Unit Tannery

Sludge Hair Fibres

EPA limits Grade A

Dry solids

General Information Moisture loss – 400C % w/w 71.5 60.5 General Chemistry* Total Nitrogen % w/w 1.2 4.6 Total Phosphorus % w/w 0.33 <0.06 Total Potassium % w/w 0.07 <0.04 Total Sulfur % w/w 0.45 1.5 Total Calcium % w/w 2.5 2.0 Total Magnesium % w/w 0.35 0.02 Total Sodium % w/w 0.18 0.64 Total Manganese % w/w 0.16 0.002 Total Iron % w/w 0.34 0.024 Total Boron % w/w 0.0078 <0.0003 Total Chloride % w/w Total Molybdenum % w/w <0.001 <0.001 Heavy Metal Chemistry*

Total Cadmium mg/kg <1.0 <1.0 3 3 Total Chromium mg/kg 3500 22 100 50 Total Cobalt % w/w <0.001 <0.001 Total Copper % w/w 0.002 <0.001 100 60 Total Lead mg/kg <10.0 <10.0 150 150 Total Zinc mg/kg 0.014 0.009 200 200 Total Arsenic mg/kg 1.5 0.1 20 20 Total Mercury mg/kg 0.02 <0.01 1 1

*Results are expressed on an as received basis Analysis of %Moisture, pH, EC, C/N and Total N of waste from Tannery No.2 1999 Units Tannery Sludge Hair Fibres Moisture (400C) % w/w 60.5 73.5 pH [H2O] 7.3 8.8 EC dS/m 3.3 15.4 C/N [calc.] 4.5 8.1 Total Nitrogen % w/w 1.2 4.6


58

APPENDIX 1.6 Food Processor Wastes (Canned Beans)- Company 1 Chemical Analysis of waste from Food Processor / Beans No.1 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste and Limits for contaminants in compost (Dry solids). 1999 Analyte Unit Food Waste (Beans) EPA limits

Grade A Dry solids

General Information Moisture loss – 400C % w/w 73.5 General Chemistry* Total Nitrogen % w/w 0.93 Total Phosphorus % w/w 0.06 Total Potassium % w/w <0.04 Total Sulfur % w/w <0.05 Total Calcium % w/w 0.07 Total Magnesium % w/w 0.01 Total Sodium % w/w <0.01 Total Manganese % w/w 0.003 Total Iron % w/w 0.15 Total Boron % w/w <0.0003 Total Chloride % w/w 0.03 Total Molybdenum % w/w <0.001 Heavy Metal Chemistry*

Total Cadmium mg/kg <1.0 3 3 Total Chromium mg/kg <10 100 50 Total Cobalt % w/w <0.001 Total Copper % w/w <1.0 100 60 Total Lead mg/kg <10.0 150 150 Total Zinc mg/kg 0.009 200 200 Total Arsenic mg/kg <0.1 20 20 Total Mercury mg/kg 0.03 1 1

*Results are expressed on an as received basis Analysis of %Moisture, pH, EC, C/N and Total N of waste from Food Processor / Beans No.1 1999 Units Food Waste / Beams Moisture (400C) % w/w 73.5 pH [H2O] 8.8 EC dS/m 15.4 C/N [calc.] 3.5 Total Nitrogen % w/w 0.93


59

APPENDIX 1.7 Food Processor Wastes (Potato Scrap)- Company 2 Chemical Analysis of waste from Food Processor / Potato Crisps No.2 compared with the maximum permissible limits set by Victorian EPA for land disposal of a Grade A waste and Limits for contaminants in compost (Dry solids). 1999 Analyte Unit Potato

Waste Potato Sludge

EPA limits Grade A

Dry solids

General Information Moisture loss – 400C % w/w 92.9 1.0 General Chemistry* Total Nitrogen % w/w 0.12 <0.1 Total Phosphorus % w/w <0.06 <0.05 Total Potassium % w/w 0.18 <0.03 Total Sulfur % w/w <0.05 <0.04 Total Calcium % w/w <0.01 <0.01 Total Magnesium % w/w <0.01 <0.02 Total Sodium % w/w <0.01 0.01 Total Manganese % w/w 0.003 <0.0002 Total Iron % w/w 0.028 0.011 Total Boron % w/w 0.0013 <1 Total Chloride % w/w 0.54 0.01 Total Molybdenum % w/w <0.001 <0.0002 Heavy Metal Chemistry* Total Cadmium mg/kg <1.0 <0.3 3 3 Total Chromium mg/kg <10 100 50 Total Cobalt % w/w <0.001 <0.0001 Total Copper % w/w <0.001 <0.0002 100 60 Total Lead mg/kg <10.0 <3.0 150 150 Total Zinc mg/kg <0.001 <0.0004 200 200 Total Arsenic mg/kg <0.1 <0.0004 20 20 Total Mercury mg/kg 0.04 <0.01 1 1


Analysis of %Moisture, pH, EC, C/N and Total N of waste from Food Processors / Potato Crisps No.2 1999 Units Potato Waste Potato Sludge Moisture (400C) % w/w 92.9 1 pH [H2O] 5.3 3.7 EC dS/m 1.7 1.3 C/N [calc.] 11.8 25.8 Total Nitrogen % w/w 0.12 <0.1


60

APPENDIX 2 Chemical Analysis of Potato Waste Chemical analyses of potato wastes were carried out in accordance with the relevant Australian Standard, with the exception of nutrient (nitrogen, phosphorus, potassium, and trace elements). The Australian Standard specifies that samples are oven dried. SCL has advised that drying at 1050C can cause volatilisation of some nutrients such especially nitrogen. To avoid this problem, organic materials (compost, mulches, potting mixes) are analysed and reported at 40OC dry weight basis. The results are then converted to a dry weight basis at 1050C

61

APPENDIX 2.1 Food Processing Waste (Potato Scrap) Chemical Analysis of waste from Food Processor / Potato Scrap compared with Limits for contaminants in compost (Dry solids). Analyte Unit Potato

Scraps Potato Solids

Potato and Dirt

Dry solids

General Information Moisture loss – 400C % w/w 90.3 75.3 70.8 General Chemistry* Total Nitrogen % w/w 1.7 1.6 1.3 Total Phosphorus % w/w 1200 1700 1800 Total Potassium % w/w 16000 13000 11000 Total Sulfur % w/w 1100 1200 1300 Total Calcium % w/w 1100 230 2000 Total Magnesium % w/w 960 590 1300 Total Sodium mg/kg 250 150 16000 Total Manganese % w/w Total Iron % w/w Total Boron % w/w Total Chloride % w/w 0.11 0.44 3.7 Total Molybdenum % w/w Heavy Metal Chemistry*

Total Cadmium mg/kg <0.5 <0.5 0.5 3 Total Chromium mg/kg <5 <5 44 50 Total Cobalt % w/w Total Copper % w/w 8 4 20 60 Total Lead mg/kg <10.0 <10.0 <10.0 150 Total Zinc mg/kg 10 10 70 200 Total Arsenic mg/kg 0.056 0.050 1800 20 Total Mercury mg/kg 1

* With the exception of Cl, All Results are expressed at 400C dry weight basis

Analysis of %Moisture, pH, EC, C/N and Total N of waste from Food Processors / Potato Scrap Units Potato Scraps Potato Solids

Potato and Dirt

Moisture (400C) % w/w 90.3 75.3 70.8 pH [H2O] 5.8 6.2 5.8 EC dS/m 1.7 4.1 15.1 C/N [calc.] Total Nitrogen % w/w 39 35 25

*Results are expressed at 400C as dry weight basis

62

APPENDIX 3 Composting Trial 1:Remediation of Cut Flower Waste APPENDIX 3.1 MulchMaster Site Plan

(NOTE: = fence; = Area set aside for Trial)

TUB GRINDER

RAW FEEDSTOCK (Source Separated Stock Piles)

Built up bank to protect neighbouring site

WINDROW (Thermophilic Stage)



WINDROW (Curing Stage)

WINDROW (Curing Stage)

MULCH for sale

PUBLIC drop off point ENTRANCE

WEI

GH

BR

IDG

E

OFF

ICE

concrete bays

(Compost ready for

sale)

�

�

�

�

�

TRIAL SITE

�

DAM

Dra

inag

e Li

ne

63

APPENDIX 3.2 Monitoring Positions on Windrows

1 2 3 4 5

1

2

3

4

5

OFFICE

Mulch for sale

1

2

3

4

5

1

2

3

4

5

Mulch for sale

80%

Shr

edde

d D

omes

tic G

reen

W

aste

: 20%

Cut

Flo

wer

s

90%

Shr

edde

d D

omes

tic G

reen

W

aste

: 10%

Cut

Flo

wer

s

100%

Shr

edde

d D

omes

tic G

reen

W

aste

: 0%

Cut

Flo

wer

s

50% Shredded Domestic Green Waste: 50% Cut Flowers

64

APPENDIX 3.3 Specific Position of Monitoring Points on Windrows (* = monitoring/sampling point) * * * * * * * * * * * * * * *

The temperature readings were made at 5 equidistant positions along the length of the windrow on the east-side. At each of this 5 position, the surface temperature was taken at 3 levels on the east-side: 30cm up from the base, centre and approximately 30cm from the top. While the core temperature was only measured from the centre.

X/6

Y/4

x

y

0

Row 3

Row 2

Row 1

Position 1 Position 3 Position 2 Position 4 Position 5

65

APPENDIX 3.4 ANOVA Analysis of Core Temperature Data Results from an ANOVA analysis, which was performed to compare the Core Temperature of the Control with the core temperature of each treated compost.

DAY C0.95 F STATISTIC 10% & Control* 20% & Control* 50% & Control* 2 4.35 0.22 1.48 1.40 4 4.35 12.12 112.40 21.22 7 4.35 0.37 0.07 0.55 9 4.35 8.71 5.03 47.76 11 4.35 72.32 27.19 41.56 18 4.35 5.94 11.52 34.00 23 4.35 46.83 152.93 155.72 30 4.35 3.79 4.73 27.28 37 4.35 24.12 16.85 107.76 44 4.35 1.88 1.66 20.08 51 4.35 17.55 18.91 67.62 58 4.35 9.08 18.01 105.38 65 4.35 3.77 25.51 53.41 72 4.35 0.51 6.56 7.84 79 4.35 0.03 9.68 11.73 86 4.35 51.49 149.87 39.31 93 4.35 15.70 9.68 76.57 100 4.35 0.73 7.22 62.87 107 4.35 3.10 1.39 54.75

NOTE: H0(Treatment): The control windrow and X% Treatment [where X = 10%, 20% or 50%] have the same average effect on core temperature. Ha (Treatment): The control windrow and X% Treatment [where X = 10%, 20% or 50%] did not have the same average effect on core temperature. APPENDIX 3.5 ANOVA Analysis of dry weight data ANOVA analysis based on dry weight carnations Treatments being compared C0.95 F Statistic [Treatment]

[F & A] 5.99 2.86 [F & B] 5.99 0.35 [F & C] 5.99 1.69 [F & D] 5.99 1.36

ANOVA analysis based on dry weight of Cucumbers Treatments being compared C0.95 F Statistic [Treatment]

[F & A] 5.99 2.46 [F & B] 5.99 1.36 [F & C] 5.99 0.39 [F & D] 5.99 0.24

66

APPENDIX 4 Composting Trial 2: Remediation of Cut Flower Waste APPENDIX 4.1 Layout position of Windrows *Dimensions and layout are not to scale

The diagram above shows the original position of the windrows. A total of six windrows were constructed, two treatments were examined and each treatment was replicated three times. One was a control consisting of domestic green-wastes while the other was 50% cut flower waste. It should be noted that during the period of composting the ambient temperature and turning of the windrows contributed to the change in shape and dimensions of the windrows. Further to that the windrow position were moved occasionally to prevent obstruction of commercial composting activities but were reposition back into its original place.

OFFICE

Mulch for sale

Control 3 50% Cut Flower 2



67

APPENDIX 4.2 Windrow Dimensions

2m

4m

2m

East-side West-side

68

APPENDIX 4.3 Position of Monitoring Points on Windrows Diagrams 1 and 2 show the temperature measurement locations and sampling points on the east and west sides of a typical windrow. Diagram 3 shows the sampling point on top of the windrow. Diagram 1 East-side View of Windrow

1 2 3 4 5 The temperature measurement locations were (1,2,3,4,5) set equidistant on the line in 1/2 height of east-side.

Diagram 2 West-side View of Windrow The temperature measurement locations (1,2,3,4,5) were set evenly on the line in 1/3 height of west- side 1 2 3 4 5

Diagram 3. Top View 1 2 3 4 5 Core samples were taken from the west-side (1,2,3,4,5), east-side (1,2,3,4,5) and top (1,2,3,4,5) at a depth of 1m in from the sides and top of the windrow for analysis.

Hei

ght 2

m

Length 4m

Length 4m

Length 4m

Wid

th 2

m

Hei

ght 2

m

½ H

eigh

t 1/

3 H

eigh

t

69

APPENDIX 4.4 Raw data of the Core Temperature and Surface Temperature of the Replicated Control and Replicated 50% Treatment

Windrow 1 (Control- 100%Green-waste) West Side East Side Average DAY T0C

Surface T0C Core T0C

Surface T0C Core Core Surface

1 63.90 65.16 65.38 64.94 65.27 64.85 6 51.9 64.44 54.72 41.16 59.58 53.06 8 39.01 47.40 54.48 53.40 50.94 48.57 13 44.90 51.54 23.56 20.92 37.55 35.23 15 52.74 57.38 36.82 28.88 47.10 43.96 19 23.44 26.00 47.54 44.20 36.77 35.30 20 54.40 54.40 47.90 47.90 51.15 51.15 22 57.70 62.40 46.70 38.30 54.55 51.28 27 44.74 52.38 56.68 51.14 54.53 51.24 34 42.50 52.20 65.80 62.30 59.00 55.70 43 33.08 41.20 54.12 47.00 47.66 43.85 50 45.53 54.33 66.23 54.17 60.28 55.07 53 42.30 56.07 57.20 52.83 56.64 52.10 64 52.57 57.13 57.93 55.57 57.53 55.80 84 44.53 53.30 61.80 56.63 57.55 54.07 91 48.40 59.50 62.90 49.20 61.20 55.00 98 16.07 24.13 42.17 33.97 33.15 29.09 105 19.13 29.03 44.87 35.43 36.95 32.12 Windrow 2 (Control- 100%Green-waste)

West Side East Side Average DAY T0C

Surface T0C Core

T0C Surface

T0C Core Core Surface

1 64.88 66.28 66.18 66.76 66.23 66.03 6 57.40 62.48 61.64 56.12 62.06 59.41 8 45.88 53.06 57.60 52.78 55.33 52.33 13 50.30 53.12 24.30 22.70 38.71 37.61 15 59.28 63.92 51.00 46.04 57.46 55.06 19 39.82 39.82 54.82 48.84 47.32 45.83 20 51.74 51.86 42.56 45.32 47.21 47.87 22 59.04 65.16 58.92 53.32 62.04 59.11 27 34.78 45.32 48.56 40.22 46.94 42.22 34 33.94 67.30 67.78 67.78 67.54 59.20 43 43.14 55.70 53.26 55.70 54.48 51.95 50 48.37 55.73 52.50 43.43 54.12 50.01 53 49.13 52.90 53.03 47.9 52.97 50.74 64 46.93 50.43 50.07 46.93 50.25 48.59 84 40.40 56.00 59.87 55.5 57.94 52.94 91 32.43 45.87 54.73 45.57 50.30 44.65 98 20.93 35.63 46.07 42.83 40.85 36.37 105 23.67 33.2 46.3 41.57 39.75 36.19

70

Windrow 3 (Control- 100%Green-waste) West Side East Side Average DAY T0C

Surface T0C Core

T0C Surface


1 63.52 66.36 64.88 65.7 65.62 65.12 6 47.96 60.42 55.22 49.1 57.82 53.18 8 40.34 43.02 59.32 56.90 51.17 49.90 13 53.94 60.64 32.70 25.20 46.67 43.12 15 60.48 63.00 59.10 54.86 61.05 59.36 19 33.90 39.12 62.54 59.88 50.83 48.86 20 40.08 47.30 39.04 37.90 43.17 41.08 22 52.66 60.34 64.82 60.26 62.58 59.52 27 54.08 47.42 60.44 53.22 53.93 53.79 34 49.90 60.66 64.12 58.70 62.39 58.35 43 41.76 47.48 43.02 48.92 45.25 45.30 50 52.70 59.87 52.03 43.07 55.95 51.92 53 46.07 53.57 52.87 53.57 53.22 51.52 64 42.37 50.57 49.10 46.03 49.84 47.02 84 53.90 58.67 62.47 58.67 60.57 58.43 91 37.70 50.73 54.40 44.43 52.57 46.82 98 32.43 49.70 55.10 51.77 52.40 47.25 105 25.33 41.43 50.97 38.37 46.20 39.03

Windrow 4 (50% Cut flower Waste) West Side East Side Average DAY T0C

Surface T0C Core

T0C Surface


1 61.86 63.58 63.42 60.3 63.50 62.29 6 49.2 62.36 59.7 46.62 61.03 54.47 8 44.14 52.50 53.92 44.98 53.21 48.89 13 53.80 60.88 35.08 31.66 47.98 45.36 15 63.90 71.20 61.44 59.00 66.32 63.89 19 35.92 44.92 54.72 45.20 49.82 45.19 20 49.20 62.36 59.70 46.62 61.03 54.47 22 54.90 61.00 31.70 28.30 46.35 43.98 27 32.76 51.94 39.74 54.50 45.84 44.74 34 36.98 51.70 60.28 47.45 55.99 49.10 43 40.63 46.75 50.18 43.75 48.47 45.33 50 35.63 42.33 60.27 55.00 51.30 48.31 53 49.23 54.37 53.67 49.10 54.02 51.59 64 43.30 46.07 43.33 40.20 44.70 43.23 84 45.90 58.30 62.13 54.17 60.22 55.13 91 56.77 61.33 56.33 48.10 58.83 55.63 98 32.43 49.70 55.10 51.77 52.40 47.25 105 29.90 42.63 61.50 52.50 52.07 46.63

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Surface T0C Core

T0C Surface


1 61.66 62.8 62.42 64.02 62.61 62.73 6 46.8 57.16 51.38 39.88 54.27 48.81 8 46.42 48.16 48.22 40.28 48.19 45.77 13 59.00 50.84 20.70 25.34 35.77 38.97 15 56.90 61.46 53.74 51.64 57.60 55.94 19 29.24 39.54 46.76 33.14 43.15 37.17 20 46.80 57.16 51.38 39.88 54.27 48.81 22 46.64 54.02 56.56 50.84 55.29 52.02 27 38.76 44.50 51.48 45.50 47.99 45.06 34 34.24 53.14 58.64 43.84 55.89 47.47 43 41.13 47.17 47.80 36.72 47.48 43.21 50 48.63 57.10 54.67 48.03 55.88 52.11 53 33.87 45.00 45.67 35.87 45.34 40.10 64 37.80 44.87 42.93 35.2 43.90 40.20 84 46.53 58.17 64.63 58.2 61.40 56.88 91 51.07 57.60 59.77 51.6 58.69 55.01 98 26.80 49.03 55.97 52.93 52.50 46.18 105 22.06 41.2 61.43 56.83 51.32 45.38


Surface T0C Core

T0C Surface


1 62.94 66.18 67.5 63.62 66.84 65.06 6 43.7 57.28 54.06 50.54 55.67 51.40 8 33.78 39.56 55.08 47.84 47.32 44.07 13 55.62 59.62 39.36 33.06 49.49 46.92 15 58.10 62.62 56.06 56.62 59.34 58.35 19 25.78 29.42 49.08 49.08 39.25 38.34 20 43.70 57.28 54.06 50.54 55.67 51.40 22 66.64 73.92 64.98 46.10 69.45 62.91 27 35.16 43.10 53.24 53.24 48.17 46.19 34 51.88 52.48 65.80 62.30 59.14 58.12 43 46.20 55.44 32.96 32.96 44.20 41.89 50 43.23 56.03 52.97 44.73 54.50 49.24 53 44.53 55.57 59.77 51.77 57.67 52.91 64 54.57 57.40 55.80 46.63 56.60 53.60 84 54.23 62.40 60.47 55.7 61.44 58.20 91 48.43 59.53 62.67 49.20 61.10 54.96 98 30.43 46.93 59.30 49.03 53.12 46.42 105 35.67 57.13 63.37 55.00 60.25 52.79

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APPENDIX 4.5 ANOVA analysis of Core Temperature data Comparison between the average core temperature and surface temperature of the Control with the 50% Treatment.

Analysis of Variance (Balanced Designs): Analysis of Variance for Temperature

Source DF SS MS F P Time 17 7507.37 445.32 20.29 0.000 Treatment 1 23.12 23.12 1.05 0.306 Surface/Core 1 636.44 636.44 28.99 0.000 Time * Treatment 17 1621.26 95.37 4.34 0.000 Time * Surface / Core 17 107.70 6.34 0.29 0.998 Treatment * Surface / Core 1 6.26 6.26 0.29 0.594 Time * Treatment * Surface / Core 17 28.53 1.68 0.08 1.000 Error 144 3161.08 21.95 Total 215 13154.76

Mean Time N Temperature 0C 1 12 64.679 2 12 55.897 3 12 49.641 4 12 41.948 5 12 57.119 6 12 43.153 7 12 50.607 8 12 56.590 9 12 48.387 10 12 57.324 11 12 46.589 12 12 53.224 13 12 51.568 14 12 49.272 17 12 57.897 18 12 54.563 19 12 44.748 20 12 44.890

Treatment N Temperature/Surface Temperature/Core 1 108 51.234 49.844 2 108 51.888 53.277

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APPENDIX 5 Composting Trial 3: Remediation of Potato Solid Waste APPENDIX 5.1 Windrow Dimensions

OFFICE

Mulch for sale

Width = 2m

Length = 20m

Height = 2m EAST

WEST

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APPENDIX 5.2 ANOVA Analysis of Core Temperature data Analysis of Variance (Balanced Designs): Analysis of Variance for Temperature Source DF SS MS F P Location 19 473.39 24.92 1.42 0.120 Day 4 841.16 210.29 11.99 0.000 Type 1 428.49 428.49 24.42 0.000 Location/day 76 2395.04 31.51 1.80 0.001 Location/type 19 505.31 26.60 1.52 0.083 Day/type 4 1499.88 374.97 21.37 0.000 Location/day/type 76 2065.32 27.18 1.55 0.008 Error 200 3509.00 17.54 Total 399 11717.59

Mean location N Temperature 0C 1 20 64.500 2 20 65.250 3 20 66.550 4 20 68.150 5 20 65.750 6 20 64.150 7 20 66.300 8 20 64.950 9 20 66.100 10 20 64.450 11 20 65.200 12 20 64.550 13 20 67.700 14 20 66.200 15 20 66.350 16 20 64.700 17 20 66.450 18 20 64.450 19 20 66.250 20 20 64.900

Type N Temperature 1 200 66.680 2 200 64.610

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Day N Temperature 1 80 67.375 2 80 66.025 3 80 66.338 4 80 65.463 5 80 63.025

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APPENDIX 6 Paper presented at Contaminated Waste Industry, Future Directions Conference. Jay Maheswaran, Justine Cody, Barry Meehan, Fiona Baxter, Kim Phung and Anne-Marie Dziedzic(1999). Conversion Opportunities for Agri-Industry Wastes, Proceedings of Contaminated Wastes Industry Future Directions Conference, November 1999, Melbourne (Oral and Full paper)

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CONVERSION OPPORTUNITIES FOR AGRI-INDUSTRY WASTES Ken Peverilla, Jay Maheswaranb, Justine Cody b, Barry Meehanc, Fiona Baxterc, Kim Phungc

and Anne-Marie Dziedzicc

a Agriculture Victoria, 475 Mickleham Rd., Attwood Victoria, 3049 b State Chemistry Laboratory, Cnr South and Sneydes Rds., Werribee, 3030 c RMIT University, La Trobe St., Melbourne, 3000 Background of presenter; Dr Ken Peverill Ken Peverill is the General Manager, Environment and Resources Group, Agriculture Victoria. He has extensive experience in soil science and plant nutrition and is the author of almost 100 journal and conference papers in these areas. He was responsible for the establishment of standards for Victorian fertiliser Regulations and has served on numerous State and Federal working parties to set standards relating to sustainable environmental management issues. Recently he has played a key role in joint Research and Development initiatives focussed on the utilisation of Agri-industry Wastes in Agricultural activities. Introduction The disposal of wastes to landfill is a significant cost to manufacturing industries resulting in increased production costs and reduced profitability. Disposal of solid wastes to landfill can have serious ecological implications as well as loss of potentially valuable resources. Further, disposal of liquid waste streams to waterways in both rural and Metropolitan regions is quite unacceptable and strategies for reuse of these resources need to be developed. In 1998 the Environment Protection Authority (EPA) unveiled a new Industrial Waste Strategy which is specifically targeted at solid and liquid wastes generated by Victorian industries (EPA Industrial Waste Strategy 1998). One of the key strategic objectives announced in the strategy is to maximise the economic value of resources during their life cycle through re-use, recycling and energy recovery in preference to disposal. In order to achieve this goal, it is essential that options for re-use of waste streams be explored. Wastes from agricultural industries have great potential for re-use as sources of water, organic matter, nutrients, mulches or soil conditioning agents (Rechcigl and Herbert 1997). Australian agricultural soils are generally low in nutrient status and in organic matter, which can make them highly susceptible to nutrient mining, structural decline and erosion. Re-use of waste water in the dry Australian climate is also essential not only to conserve this limited resource but also to protect ground and surface water reserves from contamination. There is therefore a prime facie case for the investigation of suitable agri-industry waste streams for development of products, which can be applied, to agricultural and horticultural soils. This paper focuses on the reuse of solid waste streams although one example of a product developed from a liquid waste stream is presented. There are a number of obvious advantages for utilisation of agri-industry waste streams in this way (Cameron et al, 1996). These include: ♦ conservation of water resources ♦ protection of freshwater and marine environments ♦ reduction of landfill inputs ♦ reduction of waste incineration

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♦ recycling of nutrients ♦ improved organic matter levels in soils ♦ improved nutrient status of soils Currently, there is little compiled information on agri-industry wastes produced in Victoria. Furthermore, wastes from such industries are often by default deemed as prescribed wastes making land disposal an expensive option. Surveying and characterising these wastes is essential before any assessment can be made of their re-use potential. If the waste streams are non-toxic and free of contamination, they can be effectively re-used by careful selection and suitable pre-treatment. By combining different waste streams, high nutrient value composted materials with consistent physical and chemical characteristics could be produced and tailored to suit various crop and soil requirements. This paper includes results of a recently conducted survey of post farm-gate agri-industry wastes produced in the Melbourne Metropolitan region that have potential for development as soil ameliorants or fertilisers. Studies undertaken at State Chemistry Laboratory (Agriculture Victoria) and more recently at RMIT University, have used agri-industry wastes either directly or after pretreatment as supplements to, or replacements for conventional fertilisers and sources of organic matter to improve soil structure and water holding capacity. Liquid and solid wastes from the wool scouring industry have been developed as commercially marketable products that could be applied to agricultural and horticultural land or used in potting media for nursery production. Current studies with solid waste from the hide and skin processing industry have shown that this waste may be used to supplement or replace nitrogenous fertilisers. Preliminary studies have also been undertaken with piggery wastes, abattoir wastes, sugar refinery wastes and cut flower wastes. This paper presents the results of a number of laboratory, glasshouse and field investigations on the application of some of these materials to agricultural and horticultural soils. The results of four case studies are included together with the waste stream survey described above. Agri-industry wastes Solid wastes from agricultural industries have great potential for re-use and represent a significant proportion (approximately 20%) of all prescribed wastes disposed of in landfills (EPA Bulletin May 1996). Many of these wastes have economically useful concentrations of essential nutrients for plant growth, are organic in nature, and can effectively be developed as useful value added resources for agricultural industries. This however, is contingent on demonstrating that agri-industrial wastes represent an attractive alternative as fertilisers or soil ameliorants. Wastes from post farm-gate agricultural operations that have the potential to be applied directly or after composting and include materials such as: ♦ animal manure and farm effluents ♦ chicken litter and manure ♦ crop residues ♦ feedlot wastes ♦ food processing wastes ♦ wool processing effluents and sludges ♦ animal hair ♦ meat processing effluents ♦ fruit and vegetable processing ♦ cut flower wastes

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Green organics alone, generated in the Western region of the Melbourne Metropolitan area constitutes about 120,000 tonnes per annum (source: Western Region Waste Management Group, 1996). Extrapolating from this, the amount of wastes from agri-industries could at least be four times this quantity and disposal costs could conceivably be several million dollars per annum. In the vicinity of the Melbourne and Metropolitan region, there are several high value agricultural enterprises (eg. Vineyards, Vegetable production, Turf grass industry, Cut flower industry, Ornamental nursery industry, etc) which can potentially utilise these wastes in their direct form or after pre-treatment for their nutrient or soil ameliorant value. Studies undertaken by the Institute of Horticultural Development, Knoxfield (Agriculture Victoria) have shown green-waste as ideal raw material for the production of mulches, composts and growing media. In the vegetable production area of Werribee, one of the most prolific areas for the production of export quality crucifers, continuous cropping for over 30 years has depleted the soil of organic matter, threatening the phasing out of this industry in the next ten years. At a rate of application that could sustain production (about 30t/ha), the potential market for suitable compost as a soil conditioner in Werribee alone could be estimated between 36,000 and 150,000 tonnes per annum. If parts of the Northern and Eastern parts of the Metropolitan area (including the Cranbourne area) are included, the market potential for value added waste products could be at least 500,000 tonnes per annum. Research currently underway at RMIT University and Agriculture Victoria is looking at the re-use potential of agri-industry wastes being produced in the Melbourne / Metropolitan area. The research project, funded by the Rural Industries Research and Development Corporation and supported by EcoRecycle and the EPA aims to quantify and qualify these wastes with the hope of developing them as value-added resources. As part of the project, an analysis of prescribed waste transport data has been carried out. The data supplied by EPA (EPA data 1997), cover a twelve-month period of all biodegradable organic waste transported in the Melbourne Metropolitan area from January-December 1997 (RIRDC Report, 1998). The data were sorted into waste types and collated, forming a valuable reference of the amounts and types of biodegradable waste generated annually. The data in Table 1 lists all statistics recorded over the twelve-month period. Table 1. Estimated total putrescible waste transported from January-December 1997 recorded in volume (m3). Waste Type Volume (m3)*

Wool scour 8100 Poultry Litter 1450 Poultry Waste (L) 2400 Seafood 3450 Tannery 4700 Meat 8150 Dairy 19550 Potato Crisp 5250 Fruit and Veg 1050 Grease & Oil 33450 Total 87550 *Note that some contractors record masses and some volumes used to generate the figures in this table have been calculated from estimated waste densities

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Samples of these wastes were then collected from a number of sources around Melbourne and chemically analysed to identify possible nutrient sources and contaminants. Results are listed in Table 2 and each analyte has been calculated on a wet weight basis On the basis of this survey several wastes have been selected for further investigation of suitable methods of pretreatment and utilisation as soil ameliorants. Most of the wastes were found to be free of heavy metal contamination. Tannery sludges were found to be particularly high in chromium and consequently could not be used directly in agricultural applications. Tannery hair was found to be high in nitrogen although the chromium levels detected in the sample obtained would suggest that this material would need to be pre-treated to remove this contaminant before it could be converted into a nutrient source for land application. Food production wastes such as potato skins could be streamed into existing green-waste composting operations as a means of diverting this material from landfill. Industry Waste

Selected Nutrients %

Selected Heavy Metals mg / L

N P K Cd Cr Cu Co Pb Zn As Hg Wool / Sludge 0.84 <0.06 0.425 <1.0 24 <0.001 <0.001 <10 0.007 2.25 0.025 average of three sites

Wool / Fibres 2.6 0.15 1.38 <1.0 17 0.002 <0.001 <10 0.007666 2.1 0.025 average of three sites

Tannery / Sludge average of two sites

1.2 0.33 0.07 <1.0 3500 0.002 <0.001 <10 0.014 1.5 0.02

Tannery / Sludge (Cr)

average of two sites

0.79 <0.06 0.11 <1.0 64000 0.002 0.003 <10 0.088 1 0.08

Tannery / Sludge (fatty)

average of two sites

0.67 <0.06 <0.04 <1.0 65 <0.001 <0.001 <10 0.002 <10.0

Tannery / Hair 4.95 <0.06 <0.04 <1.0 81 <0.001 <0.001 <10 0.009 0.1 0.07 average of two sites

Food Waste / Beans

0.93 0.06 <0.04 <1.0 <10 <1.0 <0.001 <10 0.009 <0.1 0.03

one company Potato Waste 0.12 <0.06 0.18 <1.0 <10 <0.001 <0.001 <10 <0.001 <0.1 0.04 one company

Table 2 Analytical Results for selected waste streams collected in the Melbourne / Metropolitan area May 1999 Case Studies

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A number of research projects have recently been carried out to evaluate the use of several agri-industry wastes as soil ameliorants and/or nutrient sources. The results of each of these studies are presented below. Study 1 – Wool Processing Effluent It has been estimated that a wool scour line can produce over 0.4 ML per day. The wool scouring process removes high quantities of salt and grease from the wool. Since disposal charges are based on the BOD and salt content of the effluent, disposal of it is a major cost for the wool scouring industry. A study, supported by Business Victoria, conducted in conjunction with CSIRO Division of Wool Technology (Geelong), was conducted in 1994 to investigate alternative uses for the effluent from wool scours. The effluent that is generated from the wool scouring process is called suint. The effluent from the first wash of the wool with hot water is free of detergent or other chemical additives. CSIRO has developed a technique to reduce the volume of this wash by evaporation and reduce the suspended soil particles, grease and wool by centrifugation. This concentrate was analysed and found to have high potassium content (about 11% w/w). Other nutritive elements were comparatively low in concentration and offered little value for agronomy. Levels of heavy metals and organic chemical residues were inconsequential in relation to environmental pollution and toxicity.

Replicated field trials were conducted with potatoes and pastures (where potassium nutrition is important). The concentrate was diluted to several concentrations and applied to pasture and potatoes at comparable rates to regular potassic fertilisers such as potash. The results from the pasture trials have shown that the suint with appropriate dilution can be used as an alternative potassium source and pasture yields obtained are comparable to those obtained using conventional potassic fertilisers (Table 3). Table 3. Pasture yield under fertiliser and suint treatments as sources of potassium Pasture Yield At various sites




Tonnes Ha-1 Portarlington 1.9a 2.5b 2.4b Simpson 8.1a 9.1b 9.2b Larpent 5.3 5.6 5.7

The results from the pasture trials also showed that potassium uptake by the pasture were comparable between K sources (Table 4).

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Table 4. Potassium uptake in pastures under fertiliser and suint treatments as sources of potassium Potassium uptake At various sites




Kg Ha-1 Portarlington 26.5a 43.6b 42.7b Simpson 128.9a 237.0b 226.5b Larpent 111.3a 162.9b 166.5b

Trials with potatoes showed that the yields of potatoes and potassium concentration in potatoes, treated with different sources of potassium, were comparable, but not significantly different from the nil K treatment (Table 5). A possible reason for the lack of difference was the leaching of potassium at this sandy site. Table 5. Yield and potassium uptake in potatoes treated with different forms of potassium. Control (nil K) Potash as K

source Suint as K source

Yield (tonnes ha-1) 41.7 45.6 41.9 K concentration (%)

1.89 2.00 1.91

These studies show that, • suint could be used in agriculture without affecting the yield of the crop, • the uptake of K and yield of crops in some circumstances (eg. pasture) can be comparable

to conventional potassic fertilisers such as potash • the cost of production of conventional fertilisers and suint should be compared to

determine whether suint is a financially viable alternative. Study 2 – Wool Scour Sludge Composts Disposal of wool scour waste can cost up to $ 0.5 million per scour line per annum. The pollution load of each scour line has a population equivalent of over 30,000 people. Generally, during wool scouring 35% of the total initial weight ends up as waste in either the liquid or solid streams. The cost involved in the disposal has financial and environmental consequences for scouring operations. The wool scouring industry has taken positive steps to explore the possibilities to find alternative uses for its wastes. In this pursuit, individual companies have made great strides in achieving commendable results. The State Chemistry Laboratory has assisted Geelong Wool Combing Pty Ltd. (GWC), one of the major wool processors in Australia, to work towards containing all of their wastes generated within their premises and find alternative uses for them. A zero waste output policy initiated by GWC has helped in systematically isolating each of their waste sources and then treating, characterising, and modifying them to suit alternative uses.

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During the scouring process, much of the suspended solids are removed in the first wash of the wool. Subsequent washes are centrifuged to remove the remaining suspended solids and the wool grease. Reduction of the biological oxygen demand and the suspended solids from these effluent streams through removal of these materials render the effluent clean enough for disposal to the sewer without incurring additional charges. The remaining waste streams and the solids removed are treated biologically to partially break down the materials and to further separate the suspended solids and the wool grease. While the effluent can be discharged safely, a composting procedure was developed to treat the highly modified solid wastes. The ingredients used in the composting procedure are themselves sourced from other wastes generated from industries in the vicinity. To compost the wool scour wastes GWC incorporated wood chip wastes as the bulking agent (carbon source) and waste hair from the hide and skin processing industry (nitrogen source). Effluent, high in potassium, from its own plant was used for watering during composting and as a potassium source. The resulting compost has been used in trials in nearby vegetable growing area with promising results. The soils from the market gardening area of Werribee, that has been continuously cropped for over 30 years, has poor organic matter content and soil structure. Application of soil organic ameliorants has been recommended to increase the sustainability of these soils. Results in Table 6 show that trials on broccoli with composted wool scour wastes have shown that application of compost can, • assist in the conservation of soil moisture resulting in reduced water application by about

12% (equivalent to about $22.50 ha-1 per annum), • decrease in soil bulk density resulting 12% increase in aeration porosity that contributes to

a more conducive environment for root penetration and growth, • significantly contribute to the nutrient input, and • significantly reduce the residence time of the crop contributing to early harvest. Table 6 Soil properties and broccoli harvest results after land application of composted wool scour waste

Compost Applied (t ha-1) Properties measured (after week 4/5) 0 20 80 Soil Moisture (%) 15.4a 17.9b 20.8c Loss on Ignition of Soil (%) 5.5a 7.1b 10.4c Soil Bulk Density (g cm-3) 1.31a 1.26b 1.08c Aeration Porosity (%V/V) 30.1a 28.9a 35.3b After 11.5 weeks No. of Broccoli Heads Harvested (X10-3 ha-1)

22.1a 30.1b 32.8b

Study 3 – Animal Hair Wastes During the processing of hide and skins for leather manufacturing, the hair removed is disposed as a non-prescribed waste, at a cost of about $30 – 40 per tonne. The Victorian Hide and Skin Producers Pty Ltd. (VHSP) currently process up to 90 tonnes per week and the cost of disposal of waste hair is a significant proportion of the total operating cost. The State Chemistry Laboratory assisted by the Department of Industry, Science and Tourism assisted the VHSP to characterise their waste, identify suitable markets, and conduct trials to study the suitability of the wastes for alternative uses.

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Analysis identified that the hair contained about 12% nitrogen and negligible levels of heavy metals, organochlorins or organophosphates. The nitrogen in hair was organically bound and was not available for immediate release. Trials with lettuce were conducted in the Werribee market garden area to evaluate the suitability of hair as an alternative source of nitrogen fertiliser. Milled, waste hair was surface applied to the soil at rates equivalent to up to 400% of nitrogen that is normally applied as conventional fertilisers. The application of nitrogen as hair proved to be useful in two ways; first as an organic soil ameliorant preventing moisture loss from the soil and second as an alternative source of nitrogen fertiliser. The results obtained showed that moisture retention under hair treatment was greater than under the control with no nitrogen (Table 7). Similar differences were found for plant characteristics such as plant N concentration, plant size, yield and N uptake. Table 7. Soil and lettuce characteristics as affected by application of waste hair as an alternative source of nitrogen.

Nitrogen applied as hair or fertiliser Properties measured (after week 3) 0 100% -

fertiliser 100% - hair

400% - hair

Soil Moisture (%) 15.6a 15.6a 15.8a 16.4b Plant N content (%) 4.7a 4.9a 4.7a 5.2b Plant size – width (cm) 29.8a 29.8a 30.2a 31.4b Yield (t ha-1) 76.3a 83.3ab 90.8bc 94.7c N uptake (t ha-1) 2.74a 3.23b 3.24b 3.39b The study has shown that waste hair from the Hide and Skin Processing industry can be used as an alternative source of nitrogen in vegetable production. Study 4 – Cut Flower Wastes Another waste that was identified as going to landfill, and having potential for re-use, was the off-cuts and waste from the flower growing industry. This is a major industry in Melbourne, with two main regions located in the Dandenong’s and in the outer southeastern suburbs, which produces approximately 3-4000m3 of waste a year. Growers are concerned about pathogen and pesticide transfer, so wastes are generally not re-worked back into the soil, but dumped on site or sent to landfill. A bio-remediation trial, using windrow composting, is being carried out to assess the breakdown of pathogens and pesticides, to thereby assess the possibility of re-use as a soil-conditioning agent either by the growers themselves or sold through the nursery retail outlets. A combined waste sample from several growers was analysed for pesticide residues, with several common biocides being identified (RIRDC Report 1999). A large volume of waste was then collected from three growers over a period of two weeks and transported to a municipal organic processing facility. The flower waste was incorporated into the composting process in several different concentrations and monitored over the following weeks for temperature and relative humidity. Samples were also regularly taken, and have been submitted for pesticide analysis. Glasshouse pot trials and field trials have been carried out using the finished material to determine its potential as a mulch which could be re-used in the

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flower growing industry. As this work is still in progress, the results of this study will be presented during the seminar. Outcomes and Recommendations • Various Institutes of Agriculture Victoria often working in conjunction with RMIT

University have successfully undertaken applied Research and Development to characterise modify/manage and utilise agri-industry wastes by disposal onto agricultural land

• Through sound management it is generally possible to gain benefits from water, organic matter and nutrients in wastes through land disposal

• Care must be taken to control any adverse effects from waste applications such as induced salinity and sodicity, nutrient imbalances, high BOD, contamination from organic residues and heavy metals

• Benefits also accrue to industry by reducing waste disposal costs and establishing an environmentally friendly image

• Various Metropolitan and Rural industries should fully explore the opportunities to convert high cost wastes into value added environmentally friendly by-products

References Industrial Waste Strategy, Zeroing in on Waste, Environment Protection Authority, April 1998. Rechcigl, J. E., and H. C. MacKinnon, Agricultural Uses of By-Products and Wastes, American Chemical Society 1997. Cameron, K. C., Di, H. J., and R. G. McLaren, Is Soil an Appropriate Dumping Ground for Our Wastes? , ASSSI and NZSSS National Soils Conference, July 1996. EPA Putrescible Waste Stream Data 1997. EPA Bulletin, May 1996.

Meehan, B. J., Baxter, F., and Jay Maheswaran, Progress Report RIRDC Project No RMI-10A, Re-use Potential of Agri-Industry Wastes in the Melbourne/Metropolitan Region, November 1998.

Meehan, B. J., Baxter, F., and Jay Maheswaran, Progress Report RIRDC Project No RMI-10A, Re-use Potential of Agri-Industry Wastes in the Melbourne/Metropolitan Region, June 1999. Acknowledgment The research team would like to gratefully acknowledge the financial assistance provided by the Rural Industries Research and Development Corporation to undertake the majority of this research program.

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7. Glossary Composting The transformation of organic material through decomposition

into a soil-like material called compost. Invertebrates(insects and earthworms), mircrooranisms (bacteria and fungi) help in transforming the material into compost. Composting is a natural form of of recycling, which continually occurs in nature.

EPA Environmental Protection Authority

Prescribed waste Waste prescribed in the Environmental Protection (Prescribed Wastes) Regulations 1987

Putrescible waste Domestic garbage, commercial waste, vegetables, supermarket processing, deli, butchers, garden clippings etc. Waste able to be decomposed by bacterial action

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9. Photographs

List of Photos Photo 1. Collection area of cut-flower waste Photo 2. Transfer of cut-flower waste onto collection vehicle Photo 3. Mixing the cut-flower waste to create a homogeneous mix Photo 4. Cut-flower waste used in trial (approximately 24m3) Photo 5. Mixing of cut-flower waste and greenwaste to produce application rate

50% cut-flower and 50% green-waste

Photo 6. A typical windrow shape of 50% cut-flower waste and 50% green-waste

(sprinkler system position on top of windrow)

Photo 7. Potato waste being unloaded onto trial site (40 tonnes of potato waste

were collected over a ten-day period)

Photo 8. Composition of potato waste (shavings, culled potato, dirt and potato

pieces)

Photo 9. Incorporation of potato waste with green-waste Photo 10. Mixture of potato waste & green-waste Photo 11. Homogenised potato & green-waste

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Photo 1 Collection area of cut-flower waste

Dry Cut flower waste Cut flower waste out in the field for >1 week

Moist and green Deposit of flower waste transferred from cut-flower production

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Photo 2. Transfer of cut-flower waste onto collection vehicle i) Transfer using the front-end loader

ii) Transfer using forklift

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Photo 3. Mixing the cut-flower waste to create a homogeneous mix

Photo 4. Cut-flower waste used in trial (approximately 24m3)

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Photo 5. Mixing of cut-flower waste and green-waste to produce application rate 50% cut-flower and 50%green-waste

Photo 6. A typical windrow shape of 50% cut-flower waste and 50% green-waste (sprinkler system position on top of windrow)

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Photo 7. Potato waste being unloaded onto trial site (40 tonnes of potato waste were collected over a ten-day period)

Photo 8. Composition of potato waste (shavings, culled potatos, dirt and potato pieces)

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Photo 9. Incorporation of potato waste with green-waste

Photo 10. Mixture of potato & green-waste

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Photo 11. Homogenised potato & green-waste

Re-use Potential of Agri-Industry Wastes...iii Foreword Wastes from agricultural industries have...

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