Eugene/Springfield Water Pollution Control Facility 1984-1991

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section E: RESIDUALS MANAGEMBNT FACII,ITIES OPERATIONS Page 43 sites andspreadby6,000-gallontank trailers. When fieldconditionsprevent trailerspreading,the sludge is applied with irrigation equipment. Smaller quantities of dewatered sludge also have been applied. Dewatered sludge is trucked to appli- cation sites in dry-box trailers, stockpiled at the application site, then loaded into a field spreader and applied. A maj or goal of the program is to move to a dried sludge application process. Composting the sludge to reduce pathogens may allow the plant to de- velop aerogram to sell sludge to the public. The final EPA rules on sludge disposal will ultimately determine disposal options. • Monitoring Sludge is strictly monitored at each of the sludge processing locations. Regular samples are taken from the sludge holding tanks at the regional plant and also from sludge lagoons, wells, and applica- tion sites. A final sample is taken at the site after the sludge is applied, regardless of whether it was applied in a liquid, dewatered, or dried form. The samples are used to establish agronomic loading rates and site life calculations and to meet federal and state reporting requirements. Each sludge sample is analyzed for pH, total solids, volatile solids, nitrogen, heavy metals, phenols, and organic priority pollutants. In addition, well and soil samples are analyzed for conductivity, total dissolved solids, chemical oxygen demand, fecal and total coliform, enterococci, total organic carbon, biochemical oxygen demand, and cation exchange capacity. OUTLOOK Over the next few years, the Residuals Manage- mentstaff will focus on further developing sludge handling and utilization practices, with an empha- sis on developing a dried sludge program that can be marketed to the public. Staff will conduct tests to determine whether composting is a viable method for further reducing pathogens. The proposed EPA rules for the disposal of sewage sludge will affect both current and future practices. • Dried Sludge Program The immediate goal for sludge management opera- tions is tosuccessfullyoperate the new dried sludge facility and to purchase the equipment needed to handle and apply the sludge in a dried form. • Marketing of Sludge Staff will be investigating pathogen reduction in the treatment process for digestion, facultative sludge lagoons, and air drying beds. Studies indi- cate pathogens can be reduced enough to meet EPA guidelines and qualify for public marketing. Staff hopes to reduce pathogen levels beyond those achieved through the anaerobic sludge digestion. The concept is to establish a program where the publicpays forandpicks up the compostedproduct at the Sludge Management Facility. This would result in significant cost savings by eliminating sludge hauling costs. Biosolids can be applied to agricultural land as a liquid (left) or as a dried product (above).