Dimitris Dermatas

• Doctor of Philosophy
• Professor (Full) at National Technical University of Athens

The European Union (EU) currently addresses the issue of contaminated land management through the national frameworks of its member states, as there is no such EU legislation thus far. However, with the introduction of the new EU Soil Strategy and the anticipated Soil Monitoring Law, EU countries are poised to receive a unified legislative tool tha...

Tourism industry is strongly connected with economic growth and urban development especially in coastal areas. Circular economy and EU Green Deal are close ly related to this activity and tourism needs to adopt strategies to reduce wastes and use adequate manegement systems.

This study aims at investigating the efficiency of calcium polysulfide (CPS) as a reducing agent for decontamination of a heavily Cr(VI)-contaminated aquifer. Batch experiments were carried out in order to evaluate the effect of time, CPS concentration and the presence of soil on the reductive behavior of CPS. CPS was used at several stoichiometric...

The holistic approach of Driver-Pressure-State-Impact-Response (DPSIR) methodology was applied to selected Cr(VI) impacted groundwater bodies of Central Greece. The main driving forces in the study areas are agricultural activities, urban and industrial development as well as tourism. The main pressures induced by the anthropogenic activities are f...

The changing climatic conditions are imposing a vital re-consideration on the hydro-chemical pathways for contaminants. The circumference Mediterranean countries will be possibly under imminent water stress. The present study attempts to identify the sources and the leaching capacity of Cr(VI) in a coastal alluvial fan and aeolian soil and in a ser...

Chromate is considered as a serious environmental problem due its toxicity. Iron nanoparticles produced by green tea polyphenols (GT-nZVI) is a powerful reductant, which can effectively reduce Cr(VI) to Cr(III). Nano ZVI suspension was initially conceived ideal for direct injection in the contaminated aquifers. However GT-nZVI presents limited mobi...

Multi wall carbon nanotubes (MWCNTs) are carbonaceous nanomaterials with novel adsorption properties. In this study MWCNTs were used as adsorbents for hexavalent chromium, Cr(VI), and the influence of operating parameters, on adsorption process, such as pH, MWCNTs and Cr(VI) concentration, and contact time have been investigated. Batch and column e...

CrITERIA project is about alternative water management practises under the imminent climate change. Cr contamination was selected as the water threat to be studied and Oman was the dry end environment. Oman has the most complete and extensive ophiolite nappe yet with the minimun attention in geogenic Cr contamination. Here, we test among others the...

The holistic approach of the Driver-Pressure-State-Impact-Response (DPSIR) analytical framework in combination with Geographical Information Systems was applied to selected Cr(VI) impacted groundwater bodies. For the characterization of water-quality "state" 157 samples including field blanks were collected during the wet and dry seasons of 2017 an...

Chromate is a pollutant often found in groundwater and considered a serious threat for humans and ecosystem. Iron nanoparticles produced by green tea polyphenols (GT-nZVI) is a powerful reductant, appropriate for the reduction of Cr(VI) to Cr(III). GT-nZVI suspension was initially conceived ideal for direct injection in the contaminated aquifers. H...

According to Water Framework Directive 2006/118/EC the members states of the European Union have to take into account the natural background levels in order to set threshold values for the assessment of groundwater chemical status. In the present comparative study, a total of 134 groundwater samples were collected during the wet and dry seasons of...

Nano zero valent iron (nZVI) is highly reactive, targets a wide range of contaminants and is considered as a promising material for the in situ remediation of contaminated aquifers. Injection of nZVI suspension is a remedial option for the in-situ reduction and immobilization of pollutants in aquifers. The goal of the present study was to evaluate...

Nanotechnology has a great potential for providing efficient, cost-effective, and environmentally acceptable solutions to face the increasing requirements on quality and quantity of fresh water for industrial, agricultural, or human use. Iron nanomaterials, either zerovalent iron (nZVI) or iron oxides (nFeOx), present key physicochemical properties...

AGU Fall Meeting, New Orleans 11-15 December 2017

In this study the results of a pilot-scale injection of green iron nanoparticles (GT-nZVI) and the formation of a reaction zone (RZ) for Cr(VI) removal are presented. A pilot scale tank was constructed with dimensions 1.5m (height) × 2.5m (width) × 3.75m (length) which was filled with 24 tons of soil. A network of 48 sampling points was installed i...

In recent years, high concentrations of hexavalent chromium (Cr(VI)) have been found in the groundwater system of the Asopos River Basin. This work focuses on a Cr(VI) plume detected in the industrial area of Inofyta, the most important contamination hot spot of the Asopos River Basin. A groundwater flow and Cr(VI) transport model was developed to...

Two different cases of Cr(VI) contaminated ophiolitic aquifers are presented herein. The first is located at Vergina (Northern Greece), where the maximum Cr(VI) concentration measured was 64 μg/L, being one of the highest geogenic concentrations recorded globally in areas with similar geological background. The second case is located at Inofyta (Ce...

The present study reports on the preliminary investigation of three low-cost natural materials with respect to their chromium(VI) removal efficiency from contaminated water. The tested materials were reed, in milled and chopped form, compost, and dewatered sludge from a municipal wastewater treatment plant. The chromium(VI) removal capacity of the...

In this study the removal of hexavalent chromium (Cr6 +) by serpentine sediments was investigated in order to delineate Cr6 + sorption behavior in aquifers with ultramafic geologic background. Batch experiments were conducted in order to determine the influence of several parameters on Cr6 + removal, including the pH of the sediment solution, miner...

Weathering of ultramafic rocks has been linked to the occurrence of elevated concentrations of hexavalent chromium (Cr(VI)) in soils, sediments, and groundwater. Ultramafic rocks and the derived serpentine soils and sediments are encountered in populated areas around the world and present high Cr concentrations, with an average of 2200 and 2650 mg/...

The adsorption process is an important factor that affects the transport of heavy metals, like hexavalent chromium (Cr(VI)), in the aquifers. The presence of iron (hydr)oxides, such as hematite and goethite, is a parameter that affects adsorption significantly. In this study Cr(VI) adsorption on ophiolitic soil and on hematite and goethite, which w...

Chromium is a widely used metal in industrial activities, mainly in metallurgy and production of refractory and chemical products. The combination of extended industrial use of chromium with inadequate industrial waste management practices mainly of the past has led to extensive soil and groundwater contamination. However, recent studies indicate t...

The presence of elevated Cr and Ni levels in the geoenvironment may be attributed to both anthropogenic sources and natural weathering processes of ultramafic rocks. Understanding the origin of these metals is important in environmental management. This study employed statistical methods, such as factor analysis and Pearson correlations, and specia...

Within the European Union, guidance in the form of a uniform Soil Directive does not exist and member states are left to enact their own legislation governing historic soil contamination. Several historic or "legacy" sites exist in Cyprus - an EU member state with a long history of mining and a significant number of abandoned mining sites. The gold...

The abandoned gold-silver enrichment plant of Mitsero village is located in Cyprus and is an example of the long-term environmental impact of mining activity when no rehabilitation measures are undertaken. We conducted a study at a plant that has been abandoned for 70 years to investigate potential environmental contamination and, if discovered, de...

Alternative plant extracts were examined as raw materials for the synthesis of nZVI from ferric solutions. Four plants were selected for evaluation, i.e. Camellia sinensis (green tea, GT), Syzygium aromaticum (clove, CL), Mentha spicata (spearmint, SM) and Punica granatum (pomegranate, PG). Based on the results obtained, it was concluded that the r...

A forensic investigation was conducted with the aim of decoupling the contribution of geogenic and anthropogenic Cr(VI) sources in the wider area of Thiva. Groundwater and topsoil samples were collected from two Cr(VI) groundwater plumes of 160 μg/L and 75 μg/L. A series of evidence support the view that the origin of Cr(VI) detected in groundwater...

In this paper the origin and concentration of chromium (Cr) in an ophiolitic aquifer in Vergina, northern Greece were investigated. The study area has only agricultural activity so that industrial Cr contamination was precluded. Soil sampling included topsoil and drillcore samples collected down to 98 m depth. Groundwater samples were collected fro...

Accelerated one-dimensional unconfined swell tests were conducted for ferrous sulfate chromite ore processing residue (COPR) field-treated samples. The field-treated samples were subjected to wet and dry cycles over 100 days to accelerate the lithification of the samples. Parallel laboratory experiments were performed to investigate the effects of...

The adsorption of inorganic contaminants, like hexavalent chromium (Cr(VI)), is an important factor that affects their transport in the aquifers. In this paper the adsorption of Cr(VI) from aqueous solutions of 0.01 M NaCl, on the surface of ophiolitic soils, as a function of pH and initial concentration of Cr(VI), was investigated. For this aim, t...

This is the first study investigating a Cr(VI)-contaminated site in Greece. This site is located at the makeshift Inofyta industrial area among a food and drink industry, an industry of prefabricated concrete products and a metal industry, where a series of trial pits have been excavated by the local authorities to investigate the presence of Cr(VI...

Injection of a nano zero valent iron (nZVI) suspension in the subsurface is a remedial option for obtaining the in situ reduction and immobilization of hexavalent chromium in contaminated aquifers. Prerequisite for the successful implementation of this technology is that the nanoparticles form a stable colloidal suspension with good transport prope...

Soil contamination is by definition a very complex and expensive problem to solve, because a three-phase medium is contaminated by chemicals, commonly as mixtures, which not only interact together but also with each phase of the soil concurrently. Although pump-and-treat, monitored natural attenuation, and vertical engineered barriers are the most...

A promising method for obtaining sterically and chemically stable nano zero valent iron (nZVI) suspensions is the use of green tea (GT) extract for the synthesis of iron nanoparticles. However, the stability of this suspension when delivered in the subsurface depends highly on the specific geochemistry of soil material. Current work was focused on...

High levels of hexavalent chromium (Cr(VI)) in groundwater are typically attributed to anthropogenic sources. However, scientific reports over the last decade have demonstrated that relatively high levels of Cr(VI) in groundwater may also be due to natural processes. Cr(VI) is among the most significant groundwater contaminants, since it is a poten...

This study aims to investigate the potential contribution of geogenic chromium (Cr) to a contaminated aquifer of a heavily industrialized area in Greece. Until recently, high levels of Cr(VI) in the environment have always been attributed to anthropogenic activities, since the wide application of chromium in industry and the neglectful industrial w...

Remediation of contaminated sites is one of the most rapidly developing environmental restoration subjects. Site contamination results mostly from past and present anthropogenic activities and it presently constitutes one of the largest environmental liabilities for future generations to bear. The most significant categories of contaminants that ar...

Five soil samples collected from shooting ranges in 1998 were stored under a closed condition for 5 years. In addition to SEM and XRD investigations, the total organic carbon content (TOC), inorganic carbon content (TIC), δ13C and δ18O of carbonates and δ13C of plant remains were analyzed. The concentrations of total carbon contents, the sum of TOC...

Municipal solid waste (MSW) collection and disposal is a major problem of urban environment in the world today. MSW management solutions have to be technologically feasible, legally and socially acceptable and environmentally and financially sustainable. European policy is pushing to a rational management of natural resources; a promising technolog...

Chromite Ore Processing Residue was produced in large quantities in various countries and was deposited as backfill material in residential and commercial areas. There are two problems with COPR: its content in carcinogenic hexavalent chromium and its volume expansion and heave that leads to structural failures. Heave drew attention two COPR deposi...

This paper presents the results of a comprehensive research study to determine the potential causes for an inordinate distress developed on a shotcrete liner material of a tunnel located near Dallas, TX. This tunnel was originally founded on a limestone material. Distress locations were identified where possible delamination of shotcrete layer and...

This laboratory study addresses issues related to the fate and transport of tungsten and tungsten oxides in the environment (soil-water). Tungsten dioxide and tungsten trioxide were dissolved in aqueous solutions whose pH had been adjusted from 4.0 to 11.0. For initial pH smaller than 10.0, dissolved tungsten concentration remained fairly constant...

The geoenvironmental characterization of COPR at two deposition sites (New Jersey and Maryland) included geotechnical, chemical, mineralogical, and leaching analyses of three main chromite ore processing residue (COPR) types [gray-black (GB), hard brown (HB), clayey (C)]. Quantitative mineralogical analyses were instrumental in the delineation of t...

The speciation of Cr(VI) in Cromite Ore Processing Residue was investigated by means of bulk XRD, and a combination of micro-XRF, -XAS and -XRD at the Advanced Light Source (ALS), Berkeley, CA, U.S.A.. Bulk XRD yielded one group of phases that contained explicitly Cr(VI) in their structure, Calcium Aluminum Chromium Oxide Hydrates, accounting for 6...

Stabilization/solidification (S/S) processes were utilized to immobilize lead (Pb) and tungsten (W) in contaminated soils, the inclusion of W motivated by the use of the new W-based ammunition. Artificially contaminated soils were prepared by mixing either kaolinite or montmorillonite with 10% Pb and 1% W (all percentages by dry weight). Type I/II...

A quicklime-sulfate-based stabilization/ solidification (S/S) process for arsenic (As) and lead (Pb) immobilization was evaluated under “semi-dynamic” leaching conditions. In order to simulate aggressive leaching conditions the semi-dynamic leaching tests was modified by using 0.014 N of acetic solution instead of distilled water. Kaolinite-sand an...

The speciation and distribution of Cr(VI) in the solid phase was investigated for two types of chromite ore processing residue (COPR) found at two deposition sites in the United States: gray-black (GB) granular and hard brown (HB) cemented COPR. COPR chemistry and mineralogy were investigated using micro-X-ray absorption spectroscopy and micro-X-ra...

This collection of research on the subject of tungsten in the geo-environment presents a unique opportunity for academic, industrial and regulatory groups to have at their disposal current research that augments the decision- making knowledge base on the sustainable use of this unique metal. Since the invention of the incandescent bulb, the unique...

A study was performed to investigate the combined treatment of hexavalent chromium (Cr(VI)) and heaving In Chromlte Ore Processing Residue (COPR). Treatment of heaving focused on the intentional exhaustion of the mineral brownmillerlte, the hydration of which is considered responsible for volume expansion in COPR deposition sites in New Jersey. The...

Recovery of non-aqueous phase liquids (NAPLs) from the subsurface is problematic, and a serious concern for the environmental community. Many treatment approaches are focused on in-situ approaches, either in-situ treatment or recovery of NAPLs, that rely on injecting remedial fluids into the subsurface. Consequently, an understanding of flow behavi...

The toxicity characteristic leaching procedure (TCLP) is the current US-EPA standard protocol to evaluate metal leachability in wastes and contaminated soils. However, application of TCLP to assess lead (Pb) leachability from contaminated shooting range soils may be questionable. This study determined Pb leachability in the range soils using TCLP a...

Lead (Pb) contamination at shooting range sites is increasingly under environmental concern. Controlling Pb leachability from shooting range soil media is an important step to minimize Pb exposure to the surrounding environment. This study investigated stabilization of Pb in shooting range soils treated with cement, quicklime, and phosphate. Two so...

Stabilized/Solidified (S/S) waste, whether a contaminated soil, sediment or industrial waste, is usually evaluated on the sole basis of regulatory leaching tests. These tests provide point-in-time performance data and cannot alone provide a solid foundation for a reliable assessment of long term performance and overall treatment sustainability. Ins...

A bench- and pilot-scale treatability study conducted on Chromite Ore Processing Residue (COPR) from a deposition site in New Jersey showed that regulatory compliance to 20 (current) or 240 (up to 2006) mg/kg Cr(VI) was not possible using several common reductants (zero valent iron, pyrite, ferrous sulfate) due to the slow release of Cr(VI) from th...

Chromite Ore Processing Residue (COPR) has in certain cases been associated with heaving phenomena. To understand the COPR heave mechanism, the site owner sponsored research that included extensive field investigation, site characterization and laboratory programs. Based on the results, this paper presents the current knowledge on COPR heave mechan...

Chromite ore processing residue (COPR) is a solid waste that was generated by the high temperature process of chromium extraction from chromite ore using soda ash and lime. The purpose of this study was to evaluate whether brownmillerite and periclase could be transformed into other minerals to understand and predict phase transformation during wea...

Phosphate treatment of lead (Pb)-contaminated soils relies on the premise that Pb converts to the thermodynamically stable, insoluble mineral class of pyromorphites. Recent research showed that treatment performance is kinetically controlled and strongly dependent on soil pH; this study employed an acidic phosphate (P) form, monobasic calcium phosp...

Tungsten-based alloys and composites are being used and new formulations are being considered for use in the manufacturing of different types of ammunition. The use of tungsten heavy alloys (WHA) in new munitions systems and tungsten composites in small caliber ammunition could potentially release substantial amounts of this element into the enviro...

Several million tons of Chromite Ore Processing Residue (COPR) were deposited at two sites in New Jersey and Maryland, USA, and over time they exhibited extensive heaving phenomena. Ettringite, a needle-shaped mineral and an expansive mineral commonly recognized in the literature concerning cement- and soil, has been identified extensively in numer...

Six firing range soils were analyzed, representing different environments, firing conditions, and maintenance practices. The particle size distribution and lead (Pb) concentration in each soil fraction were determined for samples obtained from the backstop berms. The main factors that were found to influence Pb fragment size were the type of soil u...

Phosphate treatment has emerged as a widely accepted approach to immobilize Pb in contaminated soils and waste media, relying on the formation of the highly insoluble mineral pyromorphite as solubility-controlling phase for Pb. As such, phosphate treatment has been proposed as a Best Management Practice (BMP) for firing ranges where Pb occurs in it...

Batch tests were conducted to assess the potential use of ferrous sulfate and calcium polysulfide for the remediation of chromite ore processing residue (COPR). The remediation process entails addition of ferrous sulfate or calcium polysulfide to chemically reduce hexavalent chromium [Cr(VI)] to trivalent chromium [Cr(III)] in slurry form and pH ad...

A pugmill treatability study was conducted to remediate chromite ore processing residue (COPR) using ferrous sulfate heptahydrate (FeSO(4) x 7H(2)O) as a reductant. Two different types of COPR, with respect to particle size and mineralogy, were tested in this study. Two different stoichiometric ratios of FeSO(4) x 7H(2)O to Cr(6+) (5x and 8x) were...

The Rietveld method allows the quantification of crystalline phases and amorphous material identified by X-ray powder diffraction (XRPD) and other diffraction methods. The method assists in determining the speciation of contaminants in solid matrices both qualitatively and quantitatively in a statistically defensible approach, as it does not focus...

A fly ash-based stabilization/solidification (S/S) technique was investigated using field soil samples contaminated with arsenic (As) and lead (Pb). A semi-dynamic leaching test was used to evaluate the effectiveness of the S/S treatment. By assessing the cumulative fractions of leached As and Pb, the effective diffusion coefficient (D(e)) and a le...

Powders of chromite ore processing residue (COPR) were mineralogically evaluated using quantitative X-ray powder diffraction (XRPD) to illustrate the impacts of sample preparation procedures. Chromite ore processing residue is strongly alkaline, reactive, contains minerals of varying hardness and absorption coefficients, and exhibits significant am...

Tungsten-based alloys have been used in a wide variety of industrial and military applications. These alloys are composed mainly of tungsten (88–95%) with various combinations of nickel, cobalt, iron and copper usually making up the remaining fraction.The corrosion behaviours of five munitions grade tungsten alloys of interest have been examined us...

A pilot-scale treatment study was implemented at a deposition site of chromite ore processing residue (COPR) in New Jersey. Ferrous sulfate heptahydrate (FeSO4 x 7H2O) was employed to reduce hexavalent chromium in two dosages with three types of soil mixing equipment. XANES analyses of treated samples cured for 240 days indicated that all treatment...

A series of soil parameter and mineralogical investigative techniques were applied to assess the Pb speciation in four US Army firing range soils that presented significantly different Pb leaching regimes and soil characteristics. Soil gradation tests were complemented by total chemical analyses, X-ray powder diffraction (XRPD), Rietveld quantifica...

The immobilization of heavy metal oxyanions like chromate, arsenate and selenate, has proven to be a challenging task as they are highly mobile in alkaline environments involving S/S of contaminated media. Ettringite, a pozzolanic phase that forms in cementitious materials, has been proposed as a viable immobilization mechanism for oxyanions, where...

Since its discovery, tungsten, a transition element of Group VIb of the Periodic Table of Elements, and its compounds have been considered environmentally benign. Its presence in biological and drinking water samples in Fallon, Nevada, an acute lymphocytic leukemia cluster struck community has alarmed public health, environmental and regulatory age...

Chromite ore processing residue (COPR), which contains hexavalent chromium (Cr 6+) at concentrations typically in the range of thousands of milligrams/kilograms, was deposited over a timeframe of 50 years as fill at a site referred to as SA7 in New Jersey. Significant surface heaving associated with COPR weathering-induced mineralogical expansion h...

The presence of hexavalent chromium, Cr(VI), in soil is an environmental concern due to its effect on human health. The concern arises from the leaching and the seepage of Cr(VI) from soil to groundwater. In this paper, a stabilization technology to prevent this problem was simulated on an artificial soil contaminated with hexavalent chromium. The...

This study investigates the fate and behavior of lead (Pb), copper (Cu), antimony (Sb), and arsenic (As) in a shooting range soil. The soil samples were collected from the surface (0–15 cm) and the subsurface (15–40 cm and 40–55 cm) of a grassy and wood chip covered impact area behind a firing position. Optical microscopy images indicate significan...

Significant heaving has been observed over time at chromite ore processing residue (COPR) deposition sites in Maryland and New Jersey. Confined swell tests were employed in order to investigate the geochemical mechanisms that lead to the manifestation of heave in COPR. Ettringite, a known heave culprit in cement and soil-related literature, was ide...

Barium addition to chromite ore processing residue (COPR) was investigated in order to address (a) the pronounced heaving phenomena that are associated with mainly the presence of ettringite and (b) hexavalent chromium leaching. Sulfate was added to representative samples of grey-black (GB) and hard-brown (HB) COPR to simulate worst-case conditions...

Semi-dynamic leaching tests were conducted for artificial soils contaminated with lead oxide (PbO) in order to assess the long-term leaching behavior of lead (Pb). In order to simulate “worst case” leaching conditions, the semi-dynamic leaching test was modified using 0.014 N acetic acid (pH = 3.25) instead of distilled water. Lead contaminated art...