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Freshwater Management Series No. 1

Biosolids Management: An Environmentally Sound Approach
for Managing Sewage Treatment Plant Sludge

An Introductory Guide To Decision-Makers

A Planning Guide for Developing a Biosolids Utilisation System

Sustainable biosolids utilisation systems can be developed within a community in a relatively short period of time if lessons learned by others can be introduced and adapted to meet local needs. The following is a checklist of important steps in the system development process and is based on the experiences in Ciudad Juarez and many other communities where successful utilisation systems have been established.

Step One: Plan for the Basic Requirements
Efforts to develop biosolids utilisation systems can fail if planners and managers do not take the necessary actions to meet the following basic requirements:

Develop the awareness, understanding and commitment of the community.

If community groups and farmers are not convinced from the beginning of the benefits from land application, the utilisation system will not be successful. At the same time, community groups, particularly those from rural areas must be kept informed throughout the development process. Transparency and openness in all communications and actions are essential. A variety of methods can be used, such as seminars for farmers and agricultural organizations to discuss issues such as the quality and characteristics of biosolids, environmental and agronomic concerns, and beneficial application rates. Citizen commitment can be achieved through public education forums, site visits and involvement in advisory groups.

Recruit and train competent people.

Success depends on having competent, committed people who manage and operate these sustainable systems. If a specific region or community is to attract and retain this skilled work force, authorities must put in place career and quality-of-life incentives.

Ensure that financial resources are available.

Sludge disposal or biosolids utilisation are primarily a community, rather than a state or federal responsibility and the community needs to find the resources to finance the development and operating costs. Those communities with thousands of tonnes of sludge sitting on the treatment plant property have failed to do this. There are many sources of funds available, particularly at the design-build stage of the wastewater treatment utilities, and these funds can be pooled and focussed on developing an appropriate biosolids management system. The intrinsic nutrient value of the biosolids, which can range from US$50 to US$250 per acre depending on the source, characteristics and market, must be factored into the cost/benefit equation.

Secure the long-term support of politicians.

The understanding and commitment of politicians to sustainability goals provide the continuity needed throughout successive administrations. The lack of sustained political support throughout the process is one of the greatest obstacles to sustainable practices in the developing world. Political support can be gained through education and lobbying – education of politicians regarding the needs of, and benefits to sustainable systems, and lobbying to ensure that these issues are always at the forefront of the political agenda.

photo 5: Comparison of crops growth biosolids and chemical fertilizer
Photo 5: Comparison of crops growth biosolids and chemical fertilizer. (Source: Wastewater Treatment Centre, Environment Canada)

Step Two: Involve Stakeholders
Participation of stakeholders in setting priorities, choosing options, and implementing sustainable practices will support informed decision-making and strengthen local ownership of sustainable systems. This can be achieved by establishing multi-stakeholder committees, to provide guidance and communicate with politicians and the community at large. For Ciudad Juarez, Executive, Technical and Community Liaison Committees proved to be efficient vehicles for implementing a successful development process. Long-term continuity is maintained by establishing a Biosolids Utilisation Committee with representation from local stakeholder groups. Stakeholder roles fall into four general categories:

the public sector
community groups, and
the private sector.

It is important that these stakeholder groups understand and accept that they have specific, complementary functions and responsibilities. It is also important not to rush the process – community acceptance is essential for success.

Step Three: Establish Capacities
Capacities are the institutional and organisational tools that are used to build and operate sustaining systems and practices. For example, a utility operators training and certification programme is a capacity that is applied to produce the skilled and qualified people who then build and operate the sustaining system – in this case, the treatment plant. The four categories of essential capacities are as follows:

Education, in order to foster knowledge and understanding, and training to develop skills.

This capacity refers to educational infrastructure in the broadest sense, ranging from mechanisms to foster citizen awareness, through degree and postgraduate environmental science and engineering programmes, and specialised training courses on biosolids management and land application practices. It is important to use biosolids guidelines and regulations in assessing the types of professional and technical staff that are required for biosolids management practices, as well as in evaluating existing personnel within the water sector institutions. This human resources assessment can be used to determine the content and amount of internal training required, and the information needed by post-secondary institutions to design or re-design education/training programmes. Informal educational programmes are needed, including public, community and agricultural producer education programmes designed to foster awareness of biosolids issues, as well as to encourage farmer and community involvement in seeking and supporting viable solutions to biosolids management. Special emphasis should be placed on meeting the needs of farmers through training courses with information related to biosolids characteristics, compatible soil and crop types, agronomic application rates, limitations and restrictions to land application, waiting periods for harvesting, biosolids handling, and specific details regarding guidelines and regulations.

Monitoring ecosystems, assessing information and making decisions.

The quality of biosolids for land application must be closely monitored to ensure acceptable quality and to determine appropriate application rates. Chemical and biological characteristics must be regularly monitored, including trace elements, pathogens and odours. These parameters may vary depending on local conditions. All of these needs are served by the capacities to measure and understand the systems, through monitoring and analysis, research, technology development and forecasting. In addition, knowledge and understanding of physical, chemical and biological condition of soils and crops are needed to determine appropriate application rates and agronomic practices, and protect both human health and the environment. Qualified laboratories accredited by recognized organizations and operated by competent technicians are indispensable in this regard. Unfortunately, the shortage of reliable laboratory facilities is still a major problem and limiting factor in many regions of the world. In developing a biosolids utilisation system, authorities must undertake an evaluation of laboratories and academic and research centres in order to determine their competence level, reliability, and resource capacity. Laboratories should also have well-established QA/QC procedures and meet ISO standards.

Developing standards and achieving compliance.

Ensuring the high quality of biosolids is an important ongoing commitment for those involved in the safe, beneficial use of biosolids. Addressing this need requires the development and implementation of an effective regulatory framework involving all stakeholders, including health, agricultural, environmental and regulatory officials to ensure human health and environmental protection. Regulations are necessary for establishing quality criteria for biosolids, including the setting of strict limits for trace metals, mandating processing that destroys pathogens and minimises odour, procedures for monitoring biosolids for the presence of contaminants, restricting access to certain sites, ensuring that biosolids are effectively applied at rates that can be used by the crops being grown (i.e., the agronomic rate), and preventing runoff. The approvals process should be designed to ensure that key factors such as soil type, topography, water table level and environmental suitability are known and evaluated before biosolids are applied. This usually involves the issuance of permits and approvals by health, agriculture and environmental agencies. Qualified professionals should oversee the actual application of biosolids to land, maintain records of where and what quantities are applied, and periodically conduct tests as needed. Where possible, to provide more flexibility, considerable more land than is theoretically required should be included in the biosolids land application inventory. A Biosolids Utilisation Committee can play an important role in evaluating and improving biosolids management practices by ensuring that regulations are reviewed and modified to reflect changes that may occur related to wastewater treatment processes, pollution from industry, and agronomic practices. In countries where the practice of biosolids utilisation is new, the development of new regulations must consider local environmental and socio-economic conditions and traditions. Furthermore, before implementing any proposed new regulations, it is important to verify them through local research studies and pilot demonstration projects.

Providing accessible, affordable services and products suitable for local needs.

The market for biosolids products and services is created through this sustainable capacity building process. Awareness building and community commitment creates social demand to force government agencies to promote and work in favour of environmental and human health protection. This in turn creates demand for an educational and research system, laboratory and monitoring systems and a regulatory framework. Subsequently, the regulatory process generates a demand for environmental products and services. Success ultimately depends on the capacities that allow private enterprises and public agencies to work together and provide appropriate, affordable environmental services and products for biosolids management and utilisation. Since market forces and business practices are involved, private enterprises have an essential role to play. Equally important is the role of public authorities in providing an effective purchasing system so that products and services can be obtained through an accurate, reliable bidding and selection process.

Step Four: Establish and Maintain Sustainable Systems and Practices
In developing and implementing a sustainable biosolids utilisation system, four main goals must always be kept in mind. They are:

Protection of human health,
Protection of the ecosystem,
Restoration and preservation of the ecosystem, and
Environmentally sustainable economic development.

These four goals are achievable when an efficient and effective biosolids management system is in place, including the full complement of practices and technologies, ranging from biosolids production to biosolids utilisation. Land application of biosolids is the best means of returning nutrients and organic matter to the soil that were originally taken up in food production. It improves soil conditions, contributing to ecosystem restoration and enhances the reputation of the agricultural community by making use of a unique resource through an environmentally sound practice. In addition, the financial benefits associated with the use of this product and the avoidance of long-term costs and liabilities on the part of water utilities contributes to the goal of environmentally sustainable economic development. However, to protect human health and the environment, sustainable management of biosolids must always comply with strict guidelines and regulations.

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