Several potential sorbent materials containing iron oxides were prepared and evaluated for potential to remove divalent metals from waste waters. These included a ferrihydrite-coated sand, maghemite incorporated in Dowex[Trademark] ion exchange resin, gothite and two thermally activated ferrihydrites. Attempts to prepare sorbents from steel shot by coating with ferrihydrite or...
The central purpose of this study was to identify the
competencies of a predeparture orientation program as determined by
business/industry personnel and personnel from institutions
representing the U.S. Agency for International Development. An
additional objective was to examine the organizational framework of
existing predeparture programs to identify instructional
methodologies, administrative...
Coastal marsh vegetation is an important component in maintaining marsh stability that is threatened by changes in sedimentation, sea level rise, natural and anthropogenic disturbances, and competition from invasive species. Vegetation has been demonstrated to reduce wave energy, increase sedimentation, and decrease erosion in tidal environments under a range of...
Chromium spills on soils are causing severe groundwater contamination
problems. To increase the performance of cleanup methods, the chemical behavior
of chromium in soils and its transport through soils have to be understood. The
objectives of this research were to investigate the sorption characteristics of
chromium(VI) in soil and to...
The mixed metal compound, Chromated Copper Arsenate, or CCA, has been widely used as a wood preservative. The metal ions in CCA, CrO²⁻₄, Cu²⁺, and AsO³⁻₄, have been found in contaminated surface and subsurface soils and groundwater nearby some wood preservative facilities and nearby wood structures. Iron oxides are a...
Sediments are the major compartment in aquatic environments for many materials of toxic or nutrient concern. The lack of knowledge of the phase associations of toxic metals in sediments is the largest deficiency in our understanding of the environmental hazard posed by metal contamination. This study examined the sedimentary partitioning...
Chromium, an element of widespread use, is toxic in some
forms. Improper disposal of waste chromium products has
resulted in contamination of many sites throughout the United
States, including the United Chrome Products Superfund site
in Corvallis, Oregon. A better understanding of chromium
chemistry is needed to facilitate the remediation...