Soil risk assessment of As and Zn contamination in a coal mining region using geostatisretics

Δημοσίευση σε επιστημονικό περιοδικόSummarization: The present paper aims to map As and Zn contamination and assess the risk for agricultural soils in a wider disposal site containing wastes derived from coal beneficiation. Geochemical data related to environmental studies show that the waste characteristics favor solubilisation and mobilization of inorganic contaminants and in some cases the generation of acidic leachates. 135 soil samples were collected from a 34 km2 area and analysed by using geostatistics under the maximum entropy principle in order to produce risk assessment maps and estimate the probability of soil contamination. In addition, the present paper discusses the main issues related to risk assessment in wider mining and waste disposal sites in order to assist decision makers in selecting feasible rehabilitation schemes.Παρουσιάστηκε στο: Science of The Total Environmen

Dimensionality of heavy metal distribution in waste disposal sites using nonlinear dynamics

Δημοσίευση σε επιστημονικό περιοδικόSummarization: Mapping of heavy metal contamination in mining and waste disposal sites usually relies on geostatistical approaches and linear stochastic dynamics. The present paper aims to identify, using the Grassberger–Procaccia correlation dimension (CD) algorithm, the existence of a nonlinear deterministic and chaotic dynamic behaviour in the spatial pattern of arsenic, manganese and zinc concentration in a Russian coal waste disposal site. The analysis carried out yielded embedding dimension values ranging between 7 and 8 suggesting thus from a chaotic dynamic perspective that arsenic, manganese and zinc concentration in space is a medium dimensional problem for the regionalized scale considered in this study. This alternative nonlinear dynamics approach may complement conventional geostatistical studies and may be also used for the estimation of risk and the subsequent screening and selection of a feasible remediation scheme in wider mining and waste disposal sites. Finally, the synergistic effect of this study may be further elaborated if additional factors including among others presence of hot spots, density and depth of sampling, mineralogy of wastes and sensitivity of analytical techniques are taken into account.Παρουσιάστηκε στο: Journal of Hazardous Material

Geostatistical risk estimation at waste disposal sites in the presence of hot spots

Δημοσίευση σε επιστημονικό περιοδικόSummarization: The present paper aims to estimate risk by using geostatistics at the wider coal mining/waste disposal site of Belkovskaya, Tula region, in Russia. In this area the presence of hot spots causes a spatial trend in the mean value of the random field and a non-Gaussian data distribution. Prior to application of geostatistics, subtraction of trend and appropriate smoothing and transformation of the data into a Gaussian form were carried out; risk maps were then generated for the wider study area in order to assess the probability of exceeding risk thresholds. Finally, the present paper discusses the need for homogenization of soil risk thresholds regarding hazardous elements that will enhance reliability of risk estimation and enable application of appropriate rehabilitation actions in contaminated areasΠαρουσιάστηκε στο: Journal of Hazardous Material

Geostatistical estimation of risk for soil and water in the vicinity of olive mill wastewater disposal sites

Δημοσίευση σε επιστημονικό περιοδικόSummarization: Olive mill wastewater (OMW) is often disposed of in poorly engineered evaporation ponds or various environmental receptors in most Mediterranean countries causing contamination of soils and water bodies. The aim of this work is to estimate the risk for soils and waters as a result of OMW disposal in an area of 15 km2 at Rethymnon, island of Crete, Greece. Soil, surface, and groundwater samples were collected over a period of five years and geostatistics using the kriging approach was considered for the assessment of risk. Risk maps for several pollutants, namely phenols, Ni, Cr, and available P, in soil and water were produced. The results of the study indicate the presence of hot spots in the area under investigation, mainly in the vicinity of OMW disposal sites. Finally, the fate of contaminants in affected media is discussed and a framework for monitoring of soils and water bodies in areas affected by OMW disposal is proposed.Παρουσιάστηκε στο: Desalination and Water Treatmen

Geostatistical estimation of risk for soil and water in the vicinity of olive mill wastewater disposal sites

Summarization: Olive mill wastewater (OMW) is often disposed of in poorly engineered evaporation ponds or various environmental receptors in most Mediterranean countries causing contamination of soils and water bodies. The aim of this work is to estimate the risk for soils and waters as a result of OMW disposal in an area of 15 km2 at Rethymnon, island of Crete, Greece. Soil, surface, and groundwater samples were collected over a period of five years and geostatistics using the kriging approach was considered for the assessment of risk. Risk maps for several pollutants, namely phenols, Ni, Cr, and available P, in soil and water were produced. The results of the study indicate the presence of hot spots in the area under investigation, mainly in the vicinity of OMW disposal sites. Finally, the fate of contaminants in affected media is discussed and a framework for monitoring of soils and water bodies in areas affected by OMW disposal is proposed.Presented on: Desalination and Water Treatmen