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SEGH Urban Soils and Metal Contamination Conference, March 2015 University of Texas-Arlington

07 July 2015
The United States Section of the Society for Environmental Geochemistry and Health (SEGH), along with the University of Texas-Arlington (UTA) sponsored a conference on Urban Soils and Metal Contamination: Issues & Remedies, March 30th to April 1, 2015 on the campus of UTA.

This conference provided a forum for discussion among research scientists, government agency personnel, industry representatives, remediation managers, public health practitioners, product manufacturers and decision makers with interest in the problem posed by contaminated urban soils. Conference Themes included: Elevated levels of heavy metals in urban soils, unforeseen hazard events; disaster clean-up, vulnerable populations: measuring risk, cost-effective soil remediation, barriers to clean-up, remediation guidance; decision-making process, determination of best practices and policy and reality.

The focus of this meeting was to provide a forum for attendees and presenters to exchange information on current and best practices in the area of remediating contaminated urban soils. Of the 65 conference participants were 34 speakers from across the United States, the United Kingdom, Australia, Chile, Nigeria and China and representatives from federal, state and local health agencies along with universities and industries.

First day speakers provided background on the nature and extent of urban soil contamination as well as the current risk assessment and remediation of metal contaminated urban soils. Throughout the conference, current studies and soil metal remediation projects in Nigeria, Chile, Australia, New Orleans, Joplin Missouri, Jersey City, NJ, Dallas, Texas, and other sites were discussed. Along with the soil remediation presentations were several presentations on heavy metal uptake by vegetables and fruits in urban gardens. The main impetus for these studies and projects is to reduce the exposure pathway of heavy metals to populations at risk, especial young children, by remediating contaminated urban soil.

 

 

Conference speakers and attendees at dinner in Arlington, Texas.

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Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

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    Abstract

    The fate and persistence of trace metals in soils and sludge from landfill sites are crucial in determining the hazard posed by landfill, techniques for their restoration and potential reuse purposes of landfill sites after closure and restoration. A modified European Community Bureau of Reference’s (BCR) sequential extraction procedure was applied for partitioning and evaluating the mobility and persistence of trace metals (As, Cd, Cr, Cu, Ni, Pb, Sb, Se, Zn) in soils from three landfill sites and sludge sample from Cape Town, South Africa. Inductively coupled plasma optical emission spectroscopy was used to analyze BCR extracts. The mobility sequence based on the BCR mobile fraction showed that Cu (74–87%), Pb (65–80%), Zn (59–82%) and Cd (55–66%) constituted the mobile metals in the soils from the three sites. The mobility of Cu, Zn and Ni (> 95%) was particularly high in the sludge sample, which showed significant enrichment compared to the soil samples. Geo-accumulation index (Igeo) and risk assessment code were used to further assess the environmental risk of the metals in the soils. Exposure to the soils and sludge did not pose any non-cancer risks to adult and children as the hazard quotient and hazard index values were all below the safe level of 1. The cancer risks from Cd, Cr and Ni require that remedial action be considered during closure and restoration of the landfill sites.

  • An investigation into the use of < 38 µm fraction as a proxy for < 10 µm road dust particles 2019-06-13

    Abstract

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  • Degradation of petroleum hydrocarbons in unsaturated soil and effects on subsequent biodegradation by potassium permanganate 2019-06-13

    Abstract

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