Monday, November 13, 2006 - 3:30 PM

Speciation of Elements Released from Water Treatment Residuals and their Migration through a Sandy Soil.

Jeffrey Novak, Warren Busscher, and Don Watts. USDA-ARS-Coastal Plains Res Ctr, 2611 W Lucas Street, Florence, SC 29501-1241

Water treatment residuals (WTRs) are by-products from drinking water treatment facilities that use chemical amendments to flocculate sediments from raw water sources. These residuals are composed of a variety of organic and inorganic compounds as a result of the mineral composition of the sediments, background water chemical composition and chemicals used during purification. While WTR application to phosphorus (P) enriched soils has shown successful abatement of P movement, there are environmental concerns that WTRs can also release trace elements. We examined the organic and inorganic chemical characteristics of soil and deionized water leachate from a Norfolk soil incubated for 30 and 60 d after the addition of 0 and 60 g/kg WTR. The redox status of the treatments was determined and the elemental composition was characterized in the soil and water leachate. Results indicate that the WTR significantly increasing the dissolved organic carbon, Mn, Na, and S contents and decreased soluble Al and Fe concentrations.