The results are heartening. Farmers have reported increased yields and fertilizer savings from using sludges. No instances of surface or ground water contamination have been cited as a result of sludge use. It must be noted that improper management of sludge application projects can lead to problems involving pathogens, heavy metals, flies and odors. However, when compared with possible environmental costs associated with other forms of disposal, sludge application remains as an attractive alternative in most cases.
Information is needed on the characteristics of sludges generated at wastewater treatment plants.
There is a lack of data describing the quality of sludge being used in land application projects. Educational programs are needed to train regulatory personnel and sludge management professionals in proper sludge application techniques to more precisely match application rates to crop needs. Development of safe sludge application technologies will be needed to create benefits from the use of sludges as a renewable resource.