Transport of Heavy Metals Through Accumulated Sediments in Detention/retention Ponds
Accumulation of heavy metals (Cu, Pb, Zn) in bottom sediments of detention ponds receiving highway runoff had been identified as a potential source for groundwater contamination. To assess this environmental impact, six detention ponds located in Florida were selected to investigate heavy metals accumulation in their bottom. Core sediment samples were collected from each pond, frozen and divided into six layers. The metal content after digestion with concentrated nitric acid and extractable metal by Toxicity Characteristic Leaching Procedure (TCLP) was determined for each sediment layer. Most of the metals appear to concentrate at the top 10-15 cm of the bottom sediments. The fractions of extractable metals using TCLP exhibited exponential decline with increasing fine particles less than 0.062 mm diameter and organic content. It may be feasible to remove the accumulated sediments saturated with metals from the bottom of ponds for periodic maintenance. An existing model was used to simulate the migration of metals in the sediments. Batch sorption studies and column experiments were conducted to determine the metal transport parameters required to apply and verify the proposed model. The calculated dispersion coefficients of heavy metals through sediments were four orders of magnitude smaller than the measured tracer (NaCl) dispersion coefficients in the same sediments. Predicted concentrations obtained from the transport model appeared to approximate measured values in the laboratory.
Yousef, Yousef A.
Doctor of Philosophy (Ph.D.)
College of Engineering
Civil and Environmental Engineering
Length of Campus-only Access
Doctoral Dissertation (Open Access)
Dissertations, Academic -- Engineering; Engineering -- Dissertations, Academic
Lin, L'Yu, "Transport of Heavy Metals Through Accumulated Sediments in Detention/retention Ponds" (1990). Retrospective Theses and Dissertations. 4028.