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Ultrafine nanoparticles owing to their increased surface to volume ratio, coupled with the ability to tune their surface properties through molecular modification have made them ideal for their detection and remediation of broad range of environmental contaminants. Arsenic contamination has become a worldwide epidemic and remediation of this problem needs the development of technology with improved materials and systems with high efficiency. In the present study, we have demonstrated a simple and efficient method using surface functionalized ultrafine iron oxide nanoparticles for absolute removal of arsenic from arsenic treated water with low contact time period and low adsorbent dose. The efficiency of arsenic removal has been drastically improved by considering nanoparticles of size 10 nm and subsequent surface engineering of the nanoparticles resulting more adsorption sites being exposed to arsenic. The mechanism for adsorption was identified through electron microscopic and spectroscopic studies. The adsorption equilibrium data were well fitted to Freundlich isotherm.

In Japan, many remediation methods against liquefaction have been developed since the 1964 Niigata earthquake. The methods are classified into two categories: Ground treatments to prevent liquefaction, and measure that strengthen structures to prevent or minimise damage if the ground liquefies. The remediation methods have been applied to many kinds of structures, such as oil tanks, quay walls, bridges and buildings. The effectiveness of ground treatments in preventing liquefaction has been proved during past earthquakes. However, the 1995 Kobe earthquake presented three problems: The applicability of current methods under very strong shaking (Level 2 earthquake motion), the introduction of a new design concept based on performance, and countermeasures against liquefaction-induced flow. Many studies on these problems have been conducted recently in Japan.

The US Army Corps of Engineers (USACE) has a long history related to research and evaluation of dams subjected to seismic loading. The USACE has responsibility for the safe performance of over two hundred dams in high seismic hazard areas of the US. In 1997, the USACE instituted the Dam Safety Assurance Program to provide for the modification of completed USACE dams and related facilities, when deemed necessary for safety purposes due to new hydrologic or seismic data or changes in the state-of-the-art design or construction criteria. Through this program, USACE dams are periodically evaluated for seismic hazard potential and those that are found deficient are retrofitted through appropriately designed remediation methodologies. Since the late 1980's two major dams (Sardis Dam and Mormon Island Dam) have been remediated for seismic deficiencies and two dams (Success Dam and Tuttle Creek Dam) are currently in the process of remediation design. Discussions are given on the analysis of these dams and selected remediation alternatives. This paper also highlights recent and ongoing research that the USACE is performing to improve the analysis of dams and the subsequent design of remediation measures for those found deficient. Finally, this paper briefly presents the policy that governs seismic stability evaluation of dams from the USACE perspective and issues of concern.

The remediation of Sardis Dam in Mississippi to prevent potential sliding upstream along a thin liquefiable layer in the foundation is described. The upstream slope of the embankment was stabilised by nailing it to stable foundation soils using prestressed concrete piles with 0.6 m² cross-section. This was an innovative and unusual solution in addition to being cost-effective. The paper explains how the moments and shears for design of the piles were obtained. The analytical procedures developed for this project have since been used on several dams with similar problems.

The US Environmental Protection Agency (EPA) Brownfields Program provides grants to assess and clean up brownfields. There are few studies that estimate tax revenue impacts from cleanup beyond those generated directly from within the remediated site’s property lines. This study estimates the increased residential property tax revenue attributable to brownfields cleanup at 48 sites remediated between 2004 and 2011 under the EPA Brownfields Cleanup Grants Program. Findings from a previous study of a 5% to 15.2% property value increase following cleanup at these sites are applied to the assessed values of nearby residential properties along with local tax laws, assessment ratios, and rates to estimate tax revenue gained as a result of brownfields cleanup. The estimated increase in residential property tax revenue for a single tax year from remediating 48 brownfields properties was between $29 million and $97 million (2014 USD).

This paper investigates the odor pollutant emission characteristics of a pharmaceutical enterprise in Shijiazhuang. Gas chromatography/mass spectrometry (GC/MS) was used to determine main composition, material contents and source profile. Air samples were collected. Chlorinated hydrocarbons, ketones, micromolecular sulfide, aromatic hydrocarbons, lipids, aliphatic hydrocarbons, furans and ethers were quantified. The corresponding remediations of the wastewater treatment facility were suggested in this paper, and the odor pollution and its control method were introduced.

Granulated coal ash (GCA), a by-product from coal fired power plants, has been proven to be effective in improving sediment and water qualities in the littoral regions severely deteriorated by wastewater discharge. Based on the achievements of GCA application in Japan, it is found out that GCA plays an important role in restoring the ecosystem of marine environment through various mechanisms, notably neutralizing acidified sediment due to the hydrolysis of CaO, adsorbing nutrient salts and hydrogen sulfide, and decreasing the oxygen consumption in bottom water. This paper describes the potential of using GCA in improving water quality in the Pasig River through various methods based on recent study results. The pilot study at the Estero de san Miguel is currently under preparation with the Pasig River Rehabilitation Commission.