• regulators clearly assign authority to local governments for responding to any reports of adverse consequences related to beneficial use of sludge, such as ground water contamination, odor, attraction of vermin, or illnesses. The public should be aware that state and local units of government have the necessary regulatory authority to take corrective actions against parties who have violated rules and guidance.

Concluding Remarks

In summary, society produces large volumes of treated municipal wastewater and sewage sludge that must be either disposed of or reused. While no disposal or reuse option can guarantee complete safety, the use of these materials in the production of crops for human consumption, when practiced in accordance with existing federal guidelines and regulations, presents negligible risk to the consumer, to crop production, and to the environment. Current technology to remove pollutants from wastewater, coupled with existing regulations and guidelines governing the use of reclaimed wastewater and sludge in crop production, are adequate to protect human health and the environment. Established numerical limits on concentration levels of pollutants added to cropland by sludge are adequate to assure the safety of crops produced for human consumption. In addition to health and environmental concerns, institutional barriers such as public confidence in the adequacy of the regulatory system and concerns over liability, property values, and nuisance factors will play a major role in the acceptance of treated municipal wastewater and sewage sludge for use in the production of food crops. In the end, these implementation issues, rather than scientific information on the health and safety risks from food consumption, may be the critical factors in determining whether reclaimed wastewater and sludge are beneficially reused on cropland.

The use of wastewater and sludge in the production of crops for human consumption presents a manageable risk. However, the implementation of regulations and guidelines is where problems are most likely to arise. Municipal wastewater treatment plants, private processors, distributors, and applicators must not only comply with all regulatory requirements and management practices, they must take extra steps to demonstrate to various stakeholders (e.g., neighbors, farmers, food processors, and consumers) that such compliance is occurring. This must be done through full public participation opportunities, self-monitoring and reporting programs, and public education campaigns. This is particularly true if monitoring by state or local entities is likely to be minimal. General acceptance of sludge application for food crop production probably hinges most on the development of successfully implemented projects that meet state and federal regulations and address local public concerns.

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