Summary

The Agwise project was originally established as a two pronged program:  Part A would examine planning and environmental impact issues associated with current waste management practices while Part B would examine new opportunities for the reuse of organic wastes and the impact of these altered strategies upon the overall environmental impact of the industries involved. 

There has been considerable overlap between these two major activities during the course of the project and as such this report should be read in conjunction with the Part A final report to obtain a complete overview of the project outcomes. 

This report covers an examination of the following issues: 

• The nature and volume of the organic wastes within the region;

• The demand for the nutrient resources available from these wastes within the region;

• The current status with regard to processing and re-use within the region;

• The barriers to adoption of new processing and reuse technologies;

• Evaluation of a range of alternative waste reuse technologies and systems; and

• Practical issues associated with the implementation of alternative waste reuse systems.

It does this through a series of Case Studies, Demonstration Sites, Field Day Events and How To Sheets.  In this way the project has been delivered utilising the concepts of Action Learning to facilitate maximum industry and community participation.  As a result we are indebted to all the collaborators who have helped us achieve the outputs reported here. 

Organic wastes can be reused in two ways: 

1. As a source of energy through the breakdown of the organic material present either by microbial processes to produce methane or through direct physical processes such as incineration or gasification; or 

2. As a source of soil nutrients and conditioning agents for agriculture. 

This project focused primarily upon the second opportunity due to the interest of the community in improving the biological sustainability of our agricultural soils. A significant number of private sector organisations continue to examine the potential for energy production from these waste streams, but at this point no practical opportunity has arisen. The availability of government financial incentives for waste-to-energy conversion schemes may change this situation. 

The sale of high value retail products to the home horticultural market is often seen as the ultimate waste processing solution. Although this market is economically large, it may not be sufficiently large in volume terms to utilise the entire nutrient materials produced on an annual basis from this region. Moreover, the continued removal of organic material from the QMDB exacerbates the mining cycle associated with the decline in soil fertility of our agricultural lands. 

As a result the team focused its efforts on reuse options within agriculture. 

The key elements of interest for agriculture in a reused organic waste fall into the following categories: 

1. Organic matter for soil conditioning;

2. Macro Nutrients: Nitrogen Phosphorus and Potassium as alternatives to the inorganic supply of these nutrients;

3. Micro Nutrients: Zinc, Copper, Iron etc. as the basis of a balanced soil nutrient package; and

4. Calcium as an alternative to the use of gypsum as a soil ameliorant.

An examination of the current farming systems present within the QMDB and an analysis over time of nutrient and organic matter levels indicates an increasing need for all of the above particularly organic matter and calcium. 

There is evidence from AGWISE Part A that the current nutrient availability in solid organic wastes produced within the QMDB is below the equivalent nutrient requirements of the farming sector within the region. 

Despite the existence of some areas of localised peak loading, the region overall is running on a net nutrient deficit rather than an over load from the production of organic wastes.  In short the regions agriculture needs access to a greater volume of appropriately scheduled manure or compost applications, not less. 

However the region as a whole is not effectively utilising these wastes.  There is generally little planning or effort put into maximising the agronomic impact of recycled organic wastes within the region. 

The primary reason for this is the lack of economic incentives to do so. 

We believe that this market failure has occurred not because of an inherent lack of benefit transfer, but primarily due to improper processing and poor information transfer regarding the biological properties and value of the product sold. 

The Waste Management Industry has not yet effectively understood the key economic drivers associated with the profitable processing and reuse of organic wastes within agriculture. 

The key performance criteria of any waste management system within agriculture are as follows: 

• It must be extremely simple to manage;

• It must involve minimal infrastructure or operational cost;

• It must result in a repeatable product in terms of agronomic performance;  and

• It must negate any nutrient depletion, disease or pest transfer risk associated with the material.

An examination of the key performance criteria for waste management systems within a municipal context will be very different: and the implementation of theseUrban  waste solutions in an agricultural setting can be extremely counterproductive. 

The project clearly demonstrated the viability of a wide range of potential reuse options.  The most effective procedures studied involved simple thermophilic composting.  A complete list of "How To" sheets associated with these technologies is provided. 

The major barriers still facing the region in terms of maximising nutrient reuse identified within this study were: 

• Development of an accepted method for valuing the inorganic nutrients found within a compost with particular reference to their agronomic availability;

• A method of objectively determining the agronomic value of organic matter as applied  although the use of the term Gypsum Equivalent appears to offer great promise in this area; and

• The implementation of best practice operational guidelines by waste processing operators, which will ensure repeatable agronomic performance.   A standard set of BMP guidelines for composting has been developed and trialed within this project.

The organic wastes of the QMDB can truly be a resource for the region only when they have been objectively processed and marketed to an increasingly discerning and performance-motivated agricultural sector. 

The members of the Agwise team are extremely encouraged by the actions of all sectors of the industry in addressing these issues.  During the course of the project we have seen the development of a number of farm-based processing operations as well as the establishment of some large contract processing organisations.  All are keen to Get it Right. 

The continuing demand for Soil Carbon and Calcium will, we believe, eventually lead to the development of a mature, well managed and profitable industry based around maximising the nutrient reuse associated with all our organic waste streams within the QMDB.

Final Report

• Appendix A: 'Can Do' Series of Practical Information Sheets
• Appendix B: Compendium of Current Guidelines for Waste Management, Codes of Practice and Legal Requirements, Relevant to Rural Industries in the QMDB
• Appendix C: Demonstration Site Reports
• Appendix D: Case Study Reports

• Appendix E: Waste Resource Manual

• Appendix F: Final Report on Hygiene, Fertilizer Equivalence, Soil Pathogen Suppression, and Guidelines for Production of Cotton Gin Trash Compost
• Appendix G: Supplementary Report on Composting Cotton Trash for Soil Health
• Appendix H: Guide for Composting Gin Trash On-Site
• Appendix I: Papers Presented to Conferences and Workshops

Appendix J: Proceedings of the AGWISE Forum