HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Related articles in JEQ Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by DeVolder, P. S. Articles by Pandya, K. Search for Related Content PubMed PubMed Citation Articles by DeVolder, P. S. Articles by Pandya, K. Agricola Articles by DeVolder, P. S. Articles by Pandya, K. Related Collections Redox Processes Wetlands and Aquatic Processes Remediation Bioremediation and Biodegradation Heavy Metals

Metal Bioavailability and Speciation in a Wetland Tailings Repository Amended with Biosolids Compost, Wood Ash, and Sulfate

^a College of Forest Resources, Box 352100, Univ. of Washington, Seattle, WA 98195-2100
^b National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973
^c Dep. of Soil Science, Box 7619, North Carolina State Univ., Raleigh, NC 27695-7619

View larger version (61K): [in a new window]   Fig. 1. A diagram of the experimental units used for the study. The diagram shows the depth of the tailings, compost amendment, and water cover. It also shows the amendment, interface, and tailings sampling points.

View larger version (31K): [in a new window]   Fig. 2. Sediment redox potential (Eh) values averaged over all replicates of the north plot (NP) and south plot (SP) sediments for each sampling period for the greenhouse study. Measurements were taken in the top 2 cm of substrate.

View larger version (27K): [in a new window]   Fig. 3. Sediment pH values for the greenhouse study. Measurements were taken in the top 2 cm of substrate. Data points represent the means of all replicates averaged over north plot (NP) and south plot (SP) sediment for each sampling date.

View larger version (25K): [in a new window]   Fig. 4. Redox potential (Eh) and pH data from the control, compost, compost + low SO4, and compost + high SO4 treatments plotted on an Eh–pH diagram for a range of Pb minerals. This diagram does not take into account changes in stability based on variable sulfur concentrations.

View larger version (44K): [in a new window]   Fig. 5. Acid volatile sulfide (AVS) to simultaneously extracted metals (SEM) ratio from the tailings at the interface and bottom level (99 d) from amended and control treatments in the greenhouse study. Different letters above bars indicate significantly different values using the Duncan–Waller means separation procedure (p < 0.05).

View larger version (38K): [in a new window]   Fig. 6. Stacked, normalized k3–weighted LIII–extended X-ray adsorption fine structure (EXAFS) spectra (chi data) for lead in sediment samples taken after 99 d of incubation with various treatments, and mineral standards. Experimental spectra (solid lines) are overlaid with spectral fits (dashed lines) based on the fitting parameters reported in Table 5.

View larger version (30K): [in a new window]   Fig. 7. Stacked radial structure function (RSF) magnitudes derived by Fourier transformation of k3–weighted, lead LIII–extended X-ray adsorption fine structure (EXAFS) spectra shown in Fig. 6. Radial distances are not corrected for phase shift, and therefore they do not reflect true interatomic distances.

View larger version (31K): [in a new window]   Fig. 8. Stacked, normalized LIII–X-ray absorption near edge structure (XANES) spectra for lead in sediment samples and standards. Sediment samples were collected at 99 d (solid line) or 207 d (dashed line) for each treatment. Data for standards are represented as solid lines for PbCO3 and PbSO4, and dashed lines for PbS and PbO.