Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 7, 2005
Publication Date: November 7, 2005
Citation: Dungan, R.S., Lee, B., Shouse, P.J., Dees, N.H. 2005. Can waste foundry sands be used to improve the infiltration rate of poorly drained soils? [abstract].ASA-CSSA-SSSA Annual Meeting Abstracts. p. 905.
Each year foundries in the United States generate several million tons of waste sand that can no longer be used to make metalcasting molds. The most common molding material is clay-coated sand, known as green sand. The majority of the waste sands, which are classified as non-hazardous industrial waste, are generally landfilled. Beneficial use of waste foundry sands (e.g., land application, soil manufacturing, and geotechnical applications) can make a significant contribution towards meeting the national goal of maximizing the use of remaining landfill capacity. Laboratory studies were conducted to determine if soil blending could be used to increase the infiltration rate of poorly-drained agricultural soils. Increasing the amount of sand in these soils will decrease the clay content and theoretically improve agronomic conditions. The soils used in our experiments were the Bearden silty clay loam (MN), Regent silty clay loam (ND), Walla Walla silt loam (WA), and Leck Kill channery silt loam (PA). Each of the soils were blended with as much as 70% aluminum or iron green sand (by weight), then packed into flow cells (7.62-cm i.d. x 7.62-cm length) at bulk densities ranging from 1.2 to 1.35 g cm-3. After hydrating the soils for three days, the saturated hydraulic conductivity of the soil blends was determined. For example, the hydraulic conductivity of Regent and Bearden soil only was 6.7 x 10-6 and 1.1 x 10-4 cm s-1, respectively. However, when these soils were blended with green sand, the hydraulic conductivity increased as the sand blending ratio increased. At 70% green sand, the hydraulic conductivities were 3.3 x 10-3 and 3.9 x 10-3 cm s-1, respectively. These data indicate that the infiltration rate of poorly-drained soils can be increased by the addition of foundry green sands. Additional data will be available during meeting time.