Search

Spent portable batteries belong to the category of hazardous waste, sometimes dumped together with non-hazardous municipal waste in landfills, resulting in various aquatic environments. Their presence in the aquatic environment leads to changes in its quality and its contamination with heavy metals or other toxic elements. This paper highlights the portable battery waste's influence on the aquatic environment in stagnant conditions. Therefore, three types of batteries and three solutions with different pH values were used to represent the possible media existing in nature: acid (pH = 4.00), rainwater (pH = 5.63), and alkaline (pH = 8.00). After 180 days, the results showed changes in the chromatics and composition of the initial solutions. The analyses showed decreased pH, increased conductivity, and the transfer of several heavy metals into solutions (Cu, Pb, Zn, Ni, and Fe). Thus, there were slight exceedances of the maximum allowed values for water quality class I (Order no. 161/2006) in the case of Cu and Pb and higher exceedances in the case of Zn, Ni, and Fe. Zinc–carbon batteries stand out because of the release of Pb and Fe ions. The same applies to lithium manganese dioxide batteries because of Ni ions as well as zinc–manganese alloy batteries because of Cu and Zn ions. Altogether, the negative influence of spent batteries on the aquatic environment is noticed, and the measures for the implementation of safe disposal and processing are necessary. [ABSTRACT FROM AUTHOR]

Soil pollution with heavy metals is a problem for the whole geosystem. The aim of the research is to identify new solutions for extracting heavy metals from polluted soils so that they can be further exploited. To this end, investigations of the physicochemical characteristics of the soil sample under study were carried out. Following the analyses, the soil was characterised as lute-coarse sand (UG) with a strongly acidic pH (4.67), a hygroscopicity coefficient (CH = 4.8% g/g), and a good supply of nutrients: nitrogen (Nt): 0.107%; mobile phosphorus (PAL): 6 mg kg−1 and mobile potassium (KAL): 26 mg kg−1, but is low in humus (2.12%). The metal content of the soil was determined by atomic absorption spectrometry (AAS), and the analyses showed high concentrations of metals (Pb: 27,660 mg kg−1; Cu: 5590 mg kg−1; Zn: 2199 mg kg−1; Cd: 11.68 mg kg−1; Cr: 146 mg kg−1). The removal of metals (Pb, Cu, Zn, Cd, and Cr) from polluted soil by different extraction agents (water, humus, malic acid, chitosan, and gluconic acid) was investigated. Metal extraction experiments were carried out in a continuous orbital rotation-oscillation stirrer at a solid/liquid/ (S/L ratio; g:mL) of 1:4, at two concentrations of extraction solution (1% and 3%), and at different stirring times (2, 4, 6, and 8 h). The yield of the extraction process is very low for all proposed extraction solutions. The maximum values of extraction efficiency are: 0.5% (Pb); 3.28% (Zn); and 5.72% (Cu). Higher values were obtained in the case of Cr (11.97%) in the variant of using humus 3% as an extraction solution at a stirring time of 6 h. In the investigated experimental conditions, the best removal efficiencies were obtained in the case of cadmium (26.71%) when using a 3% malic acid solution. In conclusion, it is considered that, from case to case, the type of extraction solution as well as the nature of the metal influence the mechanism of the depollution process, i.e., the capacity of the fine soil granules to free themselves from the pollutant metal that has adhered to them, and further research is considered necessary in the future. [ABSTRACT FROM AUTHOR]

The impact of dams and reservoirs on the aquatic ecosystem of rivers is a very important topic for water resource management. These hydrotechnical facilities change the natural hydromorphological regime of the rivers. This paper analyzed the hydrodynamic characteristics of an undeveloped riverbed section downstream of the Colibița reservoir, from the Bistrita Ardeleana River hydrographic basin. After processing the data obtained on the field, two hydraulic models were made using the MIKE 11 program, which aimed to identify the hydraulic parameters such as the wet section, the depth, and the water velocity. The first modeling was used for the flow rate of Q = 54.5 m3/s: the water depth was between 1.952 m and 2.559 m; and the water velocity varied between 1.148 m/s and 1.849 m/s. The second modeling was used for a flow rate of Q = 178 m3/s and showed that the water depth had values between 3.701 m and 4.427 m; and the water velocity varied between 1.316 m/s and 2.223 m/s. Following the granulometric analysis, the average diameter of the particle in the thalweg was D50 = 25.18 mm. The conclusion reached as a result of hydraulic modeling and granulometric analyses indicated that hydromorphological processes take place along the length of the analyzed sector, which have negative effects on water quality as well as on the instability of the riverbed. To make the riverbed safe along the entire studied length, we managed to identify some alternative solutions that have the role of stabilizing the banks, respectively, to stop the deepening of the thalweg. The alternative hydrotechnical constructions will increase the roughness of the riverbed, essentially reducing the water speed and increasing the favorable conditions for the retention of alluvium. [ABSTRACT FROM AUTHOR]

Abandoned sterile dumps can be a significant source of environmental pollution, therefore the distribution of trace elements throughout mining is vital. Monitoring environmental factors in closed mining perimeters aims to track the quality of discharged waters in the emissary and assess acid mine drainage, the quality of the soil and vegetation, stability, and the condition of the land surfaces within the perimeter of the sterile deposits. One of the primary sources of land, water and air pollution is sterile mining dumps. Knowing the source of pollution is the first step in adequately managing the affected areas. This paper investigates the physical–chemical properties and the concentrations of heavy metals in sterile dumps resulting from mining. We studied one sterile dump that was the result of ore processing and whose surface was covered with abandoned mixed ore concentrate (Pb, Zn), located in the Băiuț mining area (Romania), and a second sterile mining dump that was the result of exploration and exploitation work in the Ilba mining area (Romania). In order to determine the physicochemical characteristics of the studied sterile dumps and to determine the concentration of heavy metals, 27 sterile samples and one soil sample were taken from the Băiuț dump. Additionally, 10 sterile samples and one soil sample were collected from the Ilba dump. Aqua regia extractable concentrations of heavy metals were determined by inductively coupled plasma optical emission spectrometry. At the same time, using a portable XRF, we analyzed selected samples from each site for total metal concentrations. Furthermore, from each site, one sample was analyzed by FT–IR spectrometry. The pH values in both sterile dumps were highly acidic (≤3.5) and the content of heavy metals was generally increased. [ABSTRACT FROM AUTHOR]

The main ways of soil pollution are: on path air or atmospheric path and on terrestrial path, pollution path of direct their. Sources of air pollution are two categories: natural sources (volcanic eruptions, decomposition acts, etc.) and artificial, resulting from human activities (mining and metallurgy, energy, etc.). Solid air pollutants are those treated in the paper. They are dispersed in the air from emissions of particles which containing heavy metal ions in the atmosphere having a low sedimentation rate. Finest particles, dispersed in the air gets a considerable stability, for which will persist for a much longer time in air, thereby of increasing pollution. Direct pollution comes from direct deposit of minerals on the soil as raw materials and hazardous waste, particle entrainment by deflation surface dumps, infiltration of sewage from emplacement, accidental discharge of sewage from the emplacement and crack pipes, etc. This paper shows how it is influenced soil pollution and crack pipes, etc. from the perimeter intrauzinal and extrauzinal of SC Romplumb SA by two of the factors leading to pollution, conveying technological waste water and atmospheric emissions, respectivelly.

In order to evaluate the mobility of heavy metals in soil from Baia Mare mining region, the total, water and DTPA extractable metal contents were determined. The results showed that despite the high total metals contents and the high percentages of plant available metals only a low percent was water soluble, indicating a potential accumulation of metals in trophic chain and a potential risk for public health. Among the investigated metals, the plant available Pb and Cd species are the most severe contaminants. Significant correlations between total and DTPA extractable metals were found for Cu (r=0.510) and Pb (0.418), and also an affinity between total and water extractable metals were identified for Cu (0.366), Pb (0.502) and Zn (0.597).

This paper describes a former sterile dump site that is the result of mining and ore processing. A large site located in the Baia Mare mining area (Romania) with a significant amount of Suior-type mining concentrate deposits was selected for this research. The method of analysis used in this study is inductively coupled plasma optical emission spectrometry (ICP-OES). To characterize the contaminated area, a total of 27 sterile samples and one soil sample were collected from the studied site, which was affected by the mining activity. The samples were mineralized by a mix of hydrochloric acid and nitric acid. The disaggregation of the samples took place on a sand bath, and the concentrations of nine heavy metals were determined using an inductively coupled plasma optical emission spectrometer. The investigations provided the information for a detailed analysis allowing the assessment of trace element concentrations to establish whether the area requires remediation. This paper aims to highlight the importance of obtaining quantitative analysis data when characterizing heavy metal contaminated areas that need to undergo the remediation processes, utilizing accurate and fast systems such as modern multispectral analytical devices. The objective of this paper consists of the characterization of an area in the Baia Mare municipality, Romania, affected by high heavy metal concentrations due to sterile mining material being deposited on its surface in order to determine if the area requires remediation. [ABSTRACT FROM AUTHOR]

The layout of water resources and the complex and rational use of them have an important role in the socioeconomic activities of an urban settlement. Transversal hydrotechnical constructions such as weirs reduce the longitudinal connectivity of rivers and streams, affecting river biodiversity as well as water quality. This paper presents an alternative method that will help restore connectivity. In order to choose the best solution, topographical measurements were taken with a total topographical station, and a professional drone was used to obtain an updated orthophoto plan. After processing the data obtained in the field, engineering software capable of simulating flow, sediment transport, and water quality in rivers was used. With the help of the software, two hypotheses were realized: hypothesis A, the case with only one weir in place, and hypothesis B, when we have the proposed case with the lowering of the height of the weir's crest and the construction of three new control weirs downstream of it. In conclusion, the lowering of the current weir's crest and the construction downstream of it of three new weirs of low height would have a favorable effect from an ecological and a morphological point of view, without very big consequences on the disturbance of the flow from a hydraulic point of view. [ABSTRACT FROM AUTHOR]

Baia Mare area represents one of the most important mining areas of Romania. Although the mining activities carried out here are currently inactive (since 2012), they generated residual pollution that negatively influences all the environmental factors. The aim of the study is to evaluation of the quality of surface water from the vicinity of the city of Baia Mare, Romania. The surface water samples, collected in two distinct years (2021 and 2022), were analyzed to determine the concentration of heavy metals (Cd, Cr, Cu, Ni, Zn, Pb, Fe, Mn, and As) in order to establish the degree of contamination and the water quality through heavy metal evaluation index (HEI), heavy metal pollution index (HPI), and water quality index (WQI). The pH and the content of cations (Ca, Mg, Na, K) and anions (HCO3−, SO42−, Cl−) were also determined for complex characterization. The results showed that the water in the area had a high degree of pollution with high concentrations of Cr: 0.165–1.57 mgL−1, Ni: 0.01–0.718 mgL−1, and Cu: 0.036–0.195 mgL−1. The pollution indices showed an average level of heavy metal pollution for the collected surface water samples. The quality index demonstrated that all surface water samples in the study area were unfit for irrigation and drinking due to poor and very poor water quality. [ABSTRACT FROM AUTHOR]

The present research brings an input of information regarding the evolution of several physico-chemical parameters of two salt lakes (Lake Ocnei and Lake Rotund), part of the "Salina Turda" resort, Cluj County, Romania, by means of on-site determinations. Measurements were carried out at six depths for each sampling point. We attempted to describe the behaviors of the two lakes under different natural conditions, in order to identify the impact of anthropogenic activities on the quality parameters of the two lakes. Our studies showed that the qualitative parameters of the water fluctuate as an effect of anthropogenic activities. A comparative analysis of the results gathered during three monitoring campaigns in 2016, 2018, and 2020 indicated that water quality was affected by anthropogenic activities such as mixing water layers which were characterized by different salinity values. The lakes tended to lose basicity, pH values varying between 9 at the surface level and 7 at −4 m. The thermal stratification phenomenon was only evident in the first year of monitoring; later on, the waters of both lakes appeared thermally homogenous down to the depth of −2 m. It was determined that the lakes had an uppermost freshwater layer, which disappeared during the bathing season because of vertical mixing. Interestingly, the two lakes showcased different behaviors at depths beyond −3 m. In addition, the infiltration of meteoric water that was polluted with nitrites and nitrates demonstrated the fact that anthropogenic activities that take place in the vicinity of the lakes generate negative effects on water quality. The presence of the heliothermal phenomenon was confirmed by the measurements made in the upper segment of the lakes. This layer of water consists of a mixture of fresh and salt water. The purpose of the research was to evaluate the water quality of the lakes, monitor its evolution during the bathing season and update the situation regarding the water quality of the two salt lakes by testing specific parameters. [ABSTRACT FROM AUTHOR]

The current study was conducted to assess the level and spatial distribution of metal pollution in surface water, soil, and sediment samples from the Arieș River basin, located in central Romania, an area impacted by various mining and industrial operations. Several pollution indices, spatial distributions, cluster analyses, principal component analyses, and heat maps were applied for evaluating the contamination level with Ni, Cu, Zn, Cd, Pb, Mn, As, and Hg in the area. Based on the results of the Heavy-Metal Pollution Index and of the Heavy-Metal Evaluation Index of the surface-water samples, the middle part of the Arieș River basin, near and downstream of the gold mine impoundment, was characterized by high pollution levels. The metal concentration was higher near the tailing impoundment, with increased levels of Cu, Ni, Zn, and Pb in the soil samples and As, Cd, Pb, Na, K, Ca, Mn, and Al in the sediment samples. Ca (23.7–219 mg/L), Mg (2.55–18.30 mg/L), K (0.64–14.70 mg/L), Al (0.06–22.80 mg/L), and Mn (0.03–22.40 mg/L) had the most remarkable spatial variation among the surface-water samples, while various metal contents fluctuated strongly among the sampling locations. Al varied from 743 to 19.8 mg/kg, Fe from 529 to 11.4 mg/kg, Ca from 2316 to 11.8 mg/kg, and Mg from 967 to 2547 mg/kg in the soil samples, and Al varied from 3106 to 8022 mg/kg, Fe from 314 to 5982 mg/kg, Ca from 1367 to 8308 mg/kg, and Mg from 412 to 1913 mg/kg in the sediment samples. The Potential Ecological Risk Index values for soil and sediments were in the orders Cu > Ni > Pb > Hg > Cr > As > Mn > Zn > Cd and As > Cu > Cr > Cd > Pb > Ni > Hg > Mn > Zn, respectively, and the highest values were found around the gold mine impoundment. [ABSTRACT FROM AUTHOR]

Environmental pollution has particular implications for the whole geosystem and increases the global risk to human and ecological health. In this regard, investigations were carried out on soil samples to perform the quality status assessment by determining: pH, texture, structure and metal concentration, as well as carrying out an assessment of anthropogenic activity by determining pollution indices: Cf (contamination factor), Cd (degree of contamination), PLI (pollution load index), Er (ecological risk index) and PERI (potential ecological risk index). Analyses on soil samples showed high concentrations of metals (Cu: 113–2996 mg kg−1; Pb: 665–5466 mg kg−1; Cr: 40–187 mg kg−1; Ni: 221–1708 mg kg−1). The metal extraction experiments were carried out by bioleaching using Thiobacillusferrooxidans, microorganisms at different amounts of bioleaching solution (20 mL and 40 mL 9K medium) and a stirring time of up to 12 h. The results on the degree of contamination, pollution loading index PLI (2.03–57.23) and potential ecological risk index PERI (165–2298) indicate that the soils in the studied area have a very high degree of pollution. The decontamination procedure by bioleaching showed a decrease, but at the end of the test (12 h), the followed indices indicate high values, suggesting that bioleaching should continue. The depollution yield after 12 h of treatment is, however, encouraging: Cu 29–76%, Pb: 10–32%, Cr: 39–72% and Ni 44–68%. The use of yield–time correlation equations allows the identification of the optimal exposure time on the bioleaching extraction process to obtain optimal results. The aim of the research is to determine the soil quality, soil environmental risk, extraction of metals from polluted soils by bioleaching and to identify influencing factors in achieving high remediation yields. [ABSTRACT FROM AUTHOR]

Industrial activities in the Baia Mare, Romania area have generated strong pollution, and the impact on soil quality in the neighboring areas of the city remains unclear. The aim of the research is to investigate samples of soil from Baia Mare in order to determine the quality of the soil and also the ecological risk of the soil. This study presents among the first studies using the ecological risk assessment methodology on the soil from the Baia Mare area and aims to serve as scientific support for future studies and research. Evaluation of the soil quality state was performed by determining the physical-chemical characteristics of the soil (pH, texture, structure, and concentration of metals). Evaluation of the anthropic activity from the studied areas was conducted by determining the pollution indices: Cf; Cd, PLI, Er, and PERI. The results of this study indicate that the surface soils have very high concentrations of metals (Cd: 3.5–14.4 mg kg−1; Cu: 9.4–361.5 mg kg−1; Pb: 29.7–1973 mg kg−1), with exceedances of the limit values established in the Romanian legislation. Results regarding the degree of contamination, the PLI pollution load index (1.3–14.9), and the PERI potential ecological risk index (733.9–4686) indicate that soils in the studied area have a very high degree of pollution. [ABSTRACT FROM AUTHOR]

This study aims to investigate the quality and vulnerability of surface water (Aries River catchment) in order to identify the impact of past mining activities. For this purpose, the pollution and water quality indices, Piper and Durov plots, as well vulnerability modeling maps were used. The obtained results indicate that the water samples were contaminated with As, Fe, Mn, Pb and have relatively high concentrations of SO42−, HCO3−, TDS, Ca, K, Mg and high values for the electrical conductivity. Possible sources of the high content of chemicals could be the natural processes or the inputs of the mine drainage. Generally, according to the pollution indices, which were correlated to high concentrations of heavy metals, especially with Pb, Fe and Mn, the water samples were characterized by heavy metals pollution. The water quality index classified the studied water samples into five different classes of quality, namely: unsuitable for drinking, poor, medium, good and excellent quality. Similarly, medium, high and very high vulnerability classes were observed. The Durov and Piper plots classified the waters into Mg-HCO3− and Ca-Cl− types. The past and present mining activities clearly change the water chemistry and alter the quality of the Aries River, with the water requiring specific treatments before use. [ABSTRACT FROM AUTHOR]

Heavy metal contamination of soils is associated to mining activities and has impact on plants, micro-organisms and life support functions such as immobilisation, mineralisation, nitrification. The increasingly frequent contamination of soils with heavy metals represents a serious problem for Maramures county in Romania. The phytoremediation method can recover the infertile soil that has been polluted with excessive concentrations of heavy metals, it is a friendly environment method of remediation, can be applied on large areas, it is an in situ method and conserves topsoil. The objective of this paper consists in creating an objective and concrete image, also detailed and actual about the pollution of soils with heavy metals from different areas of Maramures county, in Romania with the purpose of highlighting the necessity of remediation and protection of the environment due to the magnitude of soil pollution. The paper has a fundamental approach based on data from specific literature and technical documentations. [ABSTRACT FROM AUTHOR]

Currently, soil pollution is a critical environmental problem that concerned all humanity due to its impact on ecological environment and human health. In order to remediate the contaminated soils, some technologies, generally based on physical, chemical, thermal, and biological processes, have long been in use. However, effectiveness of these methods depends considerably on soil type and characteristics, level of pollution and mixed contaminants present in soil. Therefore, in the present study, the pedological properties of the soil collected from abandoned mining perimeter of "Larga de Sus" from Zlatna (Alba County, Romania) were investigated in order to choose the most appropriate method for soil remediation and establish the parameters of soil remediation technology. The results indicated that soil in the area is highly acidic which favors the mobility of heavy metals in soil and other environmental components. On the other hand, most of the samples are partially structured and poorly structured while some samples are well structured, very poorly structured, or present a lack of aggregates structure. Also, the coarse sandy and loam-sandy texture of the samples was identified. Thus, considering soil properties, soil washing technology may be the appropriate remediation technology for contaminated soil in the studied area considering costs and efficiency. [ABSTRACT FROM AUTHOR]

In this study referring to the surface sediments quality of Strâmtori-Firiza reservoir, a series of heavy metals like arsenic, cadmium, copper, lead and zinc were investigated from 2017 to 2019. The samples analysis and interpretation of the results for 18 samples taken from surface sediments indicated that the correlation coefficients calculated for the metallic elements showed a significant correlation between them. Thus, highlighting their same origin in the composition of the studied surface sediments, only the value of the coefficient between As and Pb implies a statistically significant correlation. Pollution indices, calculated for each sampling site, indicated anthropogenic unpolluted surface sediments. The potential ecological risk (RI), calculated for assessing the toxicity risk related to surface benthic biomass, showed that the potential ecological risk for biological life in surface sediments was low. [ABSTRACT FROM AUTHOR]

It was carried out the monitoring of the qualitative parameters for the "Ocnei" and "Rotund" lakes located in the protected area "Salina Turda", Romania, and as well it was made a comparative analysis of the results with previous determinations. It was determined the evolution of the physico-chemical parameters on 5 segments of depth. The monitoring was carried out within 2 measurement campaigns. It has been determined that the lakes tend to lose basicity and it was found that the heliotherm phenomenon represents a stable index in comparison with previous determinations. [ABSTRACT FROM AUTHOR]

The research described in this paper performs a centralization of the dates for the open lakes for recreation and treatment, after 7 years from opening. In the context of the work, it has been achieved environmental analyses for „Ocnei" and „Rotund" lakes, located in the Salina Turda area. It has pursued the evolution of the quality parameters on depth of the lakes, intended for the tourist activity as well spa. The monitoring process was achieved through the deployment of one measurement campaign developed in April 2016. From this research results that the lakes have a tendency to lose basicity and the temperature increases with the increasing of the depth, which determines the presence of heliotherm phenomenon. [ABSTRACT FROM AUTHOR]

The paper presents investigations on the quality of environmental factors (soil and air) in the Somes industrial area of the city of Cluj-Napoca. In order to assess the quality state, the following environmental factors were investigated: soil and air. For the purpose of this study, soil samples were taken from 5 areas near trading companies chosen for monitoring. Air quality was assessed based on data collected from the industrial air monitoring station for the air in the investigated area and by collecting sedimentary particle samples. The purpose of this paper is to highlight the quality of the environment in the industrial area of Cluj-Napoca city. [ABSTRACT FROM AUTHOR]

Heavy metal contamination of soils is a widespread environmental problem associated with mining operations and has drawn considerable study interest, due to its impact on ecological environment. The present study consisted in the determination of heavy metals concentration in the soils nearby "Larga de Sus" mine (Zlatna mining perimeter, Romania). Thus, the concentration of Pb, Cu, Cr, Zn and Cd in twenty soil samples collected from ten soil sampling sites was determined by atomic absorption spectrometry. In spite of the fact that mining activity is nowadays completely stopped, the results of the chemical analysis indicated that the soil in the study area is still highly polluted with Pb since the identified concentrations of Pb (10.4-3136.0 mg/kg) in soil exceeds the intervention threshold limits established by the Romanian legislation in most of the samples collected. [ABSTRACT FROM AUTHOR]

The composting is one of the most effective recycling method of green waste. The presence of some heavy metals, such as chromium, copper, manganese and zinc may influence the compost quality. The bioavailable and unavailable metal forms for plants determined by sequential analysis showed similarities in relation to the percentages of extracted forms. The lowest percentages were recorded for the bioavailable metal forms for plants uptake. Thus, the succession F6>F5>F4>F3>(F1+F2) is characteristic for chromium, the succession F5>F6>F4>F3>(F1+F2) is characteristic for copper and zinc and the succession F5>F4>F6>F3>(F1+F2) is characteristic to the zinc and manganese. Thus, by adding some organic additives, like manure, the micronutrients and heavy metals regime is influenced. [ABSTRACT FROM AUTHOR]

The effect of three humic washing solution pH values (3.0, 7.0 and 9.6-its natural pH) on the removal efficiency of Pb and Cu from multimetal contaminated soil collected nearby "Larga de Sus" mine from Zlatna (Alba County, Romania) was investigated, at laboratory scale, by an ex-situ soil washing technique. In this study, a commercial soluble humic sample extracted from German Leonardite was used as washing agent to remove Pb and Cu from polluted soil. Soil washing experiments were conducted in a stirrer with orbital-rotation oscillation at a liquid/solid ratio (L/S ratio; mL:g) of 8:1, concentration of humic washing solution of 2% and various stirring times (4, 6, 12, 24 and 40 hours). The removal efficiency of Cu and Pb increased with increasing pH from 3.0 to 9.6. In investigated experimental conditions, the best removal efficiencies (60.3% in case of Cu and 48.08% in case of Pb) were obtained at alkaline pH values of humic washing solution. [ABSTRACT FROM AUTHOR]

The present study aimed at investigating the heavy metals concentrations in the soils around "Larga de Sus" abandoned mine (Zlatna, Romania), evaluating the potential ecological risk of heavy metal pollution and highlighting ethical aspects related to risk assessment, ecological restoration, and soil remediation. The results of the chemical analysis showed that the soil in the study area is highly polluted with heavy metals since the average concentrations of Pb (32.4–2318.1 mg/kg), and Ni (321.6–562.8 mg/kg) in soil exceed their corresponding threshold established by the Romanian legislation. The potential ecological risk index method developed by Hakanson was used to assess the potential risk of heavy-metal pollution. The results indicated that Pb and Ni showed severe and considerable potential ecological risk, while Cr had lightly ecological risk. In this case, remediation should be focused only on Pb or on all heavy metals even if they have lightly ecological risk? A scientific management technique cannot logically prescribe which choices should be selected. The interaction between human activity and the environment is complicated and difficult to quantify and risk management cannot and should not be based simply on risk assessment results. What is needed to make the right choice of the most appropriate alternative that fits our personality, culture, religion, and desires? The moral and ethical implications of ecological restoration and soil remediation (e.g. tolerance of uncertainty, responsibility, moral duty, etc.) have to be incorporated within the decision-making process in order to make optimum sustainable decisions and to achieve real environmental protection. [ABSTRACT FROM AUTHOR]

This study presents the results obtained for methylene blue removal on a commercial natural activated plant-based carbon using a simple and fast method. The optimum adsorption conditions were 200 mg/L initial methylene blue concentration, pH 1 in the initial solution, 0.5 g quantity of commercial natural activated plant-based carbon, 300 min contact time, <0.5 mm particle size of commercial natural activated plant-based carbon, and 75 rpm stirring rate. Analysis of variance indicated that the most significant parameter for methylene blue removal was the quantity of commercial natural activated plant-based carbon. Also, the results showed that the quantity of commercial natural activated plant-based carbon was the most significant parameter for methylene blue removal (24% contribution), while contact time was the least significant parameter (6% contribution). Langmuir and Freundlich isotherms suggested a favorable adsorption of methylene blue by commercial natural activated plant-based carbon, while the Dubinin-Radushkevich isotherm indicated a chemisorption process involved in methylene blue removal. [ABSTRACT FROM AUTHOR]

The bioremediation of petroleum hydrocarbons (PHCs)-polluted soils was studied by an ex-situ, lab-scale, biopile experiment with different parameters: aeration rate (1 h day−1 and 2 h day−1), soil moisture (44% and 60%), and microorganisms consortia addition (320 and 640 mL). The trial was conducted using eight treatment cells, each having different parameters, and one control cell for 18 weeks on soil containing 7600 ± 400 mg kg−1 total PHCs, taken from a former petroleum product warehouse in Sfantu Gheorghe, Covasna County (Romania). The microorganisms used for bioremediation were isolated from the native microflora of the polluted soil and grown in laboratory on culture media. A bioremediation yield up to 76% was obtained in the test cells, while in the control cell the reduction of PHCs content by 16% was attributed to natural attenuation. The results indicated that by addition of microorganisms the bioremediation is much more effective than natural attenuation. The results also revealed an accentuated decrease in PHC concentrations after 4 weeks of treatment, irrespective of the treatment conditions. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental researches regarding the optimization of a decontamination process through thermal desorption of soils contaminated with crude oil. The optimization was performed for the following desorption parameters: heating temperature of the soil and the treatment duration, by increasing the temperature from 300°C to 350°C and decreasing the treatment duration from 10, 15 and 20 minutes to 5, 10 and 15 minutes. The economic calculation of the decontamination process was performed for emphasizing the efficiency of thermal desorption. The experiments were performed on soils with loamy sand texture, loamy texture and loamy clay texture.Iit was found that the contamination degree, the texture and the treatment duration influence the thermal desorption efficiency. The analysis of how the texture influences the process of depolluting soils contaminated with various concentrations of crude oil, reveals that the loamy-sand texture has a higher efficiency, as compared to the loamy and loamy-clay textures. Moreover, it was shown that the highest efficiency is obtained by treating the loamy-sand soil for 15 minutes at 350°C. [ABSTRACT FROM AUTHOR]

The present study consisted in the determination of lead concentrations in soil samples and sterile material dumped collected from the Almaşu Mare mining area. The lead concentration in the samples collected were determined by atomic adsorption spectrometry (AAS). In spite of the fact that all mines from area are nowadays inactive, the results of the chemical analysis showed that the soils in the area are still highly polluted with lead, except at the base of the "Radeş" dump, where the lead concentrations were below the intervention thresholds. [ABSTRACT FROM AUTHOR]

The most important contaminated areas from Cluj County are the uncontrolled HCH scrap deposits from Turda city, which appeared as a result of the industrial activity of the former Chemical Plant Turda. Over the years, were identified 4 locations in the area. The four contaminated locations situated in the area of Turda city Sum up to 60000 tons of HCH polluted soil are. One of these zones is the Posta Rat area (40000 m2) which is situated on the left bank of Aries River. The objective of this paper is to carry out experimental researches in order to establish the physical-chemical properties of the soil from Posta Rat area, soil contaminated with HCH (hexachlorocyclohexane). The texture, structure, humidity and pH are the main analysis performed in order to determine the optimum cleaning technologies for the deteriorated soil as a result of the activity of the Chemical Plant in Turda. The results of the physical-chemical analysis can point out the most suitable cleaning soil solution, because as a result of the study, the characteristics of the soil are known, being much easier to identify the applicability limits of the cleaning solutions. [ABSTRACT FROM AUTHOR]

Pollution has become an issue of current concern for all humanity, because of the negative impact on the environment and human health. One of the most affected by environmental factors due to human activities is the soil, which is a sponge for contaminants. Soil contamination with heavy metals presents a major concern both global and national levels, in order to control resulted pollutants from industrial activities and finding different methods of eco-friendly and effective remedy. In the present paper is presented the Haneş mine area, the soil from here being very acid due to mining activities performed in the past. [ABSTRACT FROM AUTHOR]

The gold mining activity performed in the past in Romania has led to the pollution of the environment, the degradation of large areas of land and currently represents a significant risk to human health. As a result of the gold mining activities performed in Almasu Mare area, there were large sterile dumps and gold mine galleries that continue to give their mark on the quality of the environment and human health through the amount of heavy metals in the soil and the sterile material improperly deposited, the water that comes out of the underground to the contaminated surface and which flows into the rivers in an uncontrolled way. This paper brings details of cadmium soil pollution in the studied area. The results obtained in the analysis of cadmium concentrations through the AAS spectrometry show that the analysed soil exceeds the admissible limits provided by the legislation in force, and the sterile material collected from the sterile dumps reflects values of the Cd concentration in the interval 10.7 - 22.6 mg/kg. Due to the high concentrations present in the soil and sterile material analysed, soil remediation interventions are required in the area. [ABSTRACT FROM AUTHOR]

The current paper presents the method that designs, manufactures and tests antimony based pH sensor used for monitoring of soil pH. In the first stage of this work the method of manufacturing the sensitive antimony elements is presented. These sensitive elements are casted into different forms (conical and cylindrical). These are subjected to a series of analysis in order to determine the chemical composition of the material used 99.73% Sb, 0.27% Ti (EDX), the morphology of the structure (SEM) and the characteristics of the oxide layer (XRD). The second part of this paper explains the method of testing the manufactured antimony sensors in the reference pH solutions. Finally, the sensors are used for measurements and are tested, alternatively, in pairs, with a reference Ag/AgCl sensors found in commerce. The results of these measurements show values approximately identical at both manufactured sensors. The adapted sensor that was obtained shows a relatively fast and stable response to pH changes in aqueous solutions. Its potential has a linear relation with pH solutions and a slope of 50.95 mV/pH. [ABSTRACT FROM AUTHOR]

Past mining activities in the Almasu Mare area have led, along the time, to environmental pollution, especially of the soil. Rades gold mine is a source of negative impact today. The improperly mine closure gives the possibility of the leaks from the inside of mine to arrive at surface, creating large imbalances in soil and not only. Also, the sterile dump which is very near of Rades mine is a concern for the environment from Almasu Mare because it is not subject to ecological coating process, and the wind and rain can lead the particulates on the surface of the dump at long distances. In order to analyse the current situation of soil in Rades mine area some physico-chemical analysis were performed. The physico-chemical analysis consisted in determination of the humidity content, the structure, texture and pH of the soil. The results of experiments related to the humidity showed that the soil humidity in the forest (18.34%-34.77%) was higher than the humidity determined from the surface tailings of Rades dump (14.15% - 22.39%). The soil in forest area is partially structured and the dump material is poorly or very poorly structured. The dump material and soil texture is largely rough and the pH of tailings material taken from the Rades dump surface was in the range of 3.4-4.8 pH units and in the forest was in the range of 5.3-5.6 pH units. [ABSTRACT FROM AUTHOR]

The non-ferrous metallurgical activities led to the pollution of large areas of soil and affected the environment in a negative way. The problems generated by soil contamination with different pollutant substances have been, in the latest period in the center of attention for researchers from all around the world. The objective of this paper is to perform experimental researches in order to establish the physical-chemical properties of the soil from Copsa Mica area. The texture, structure, humidity and pH are the main analysis performed in order to proper establish the optimal soil cleaning technologies. In order to establish the actual pollution degree in the moment of soil sampling, was determined also the concentration of metals in the soil. For this purpose, were taken soil samples from two areas on three depth interval (0-40 cm). Determining the concentration of heavy metals on three depth levels offers the researcher a relevant view of the historical pollution of the area under study. As a result of these researches was established that the soil is polluted with Pb, Zn and Cd. The quantity on metals in the soil is way beyond the alert threshold. As a conclusion these soil need cleaning, which can be made through various methods, one of the being bioleaching, which is a biological cleaning method which implies using microorganisms in order to favor leaching and heavy metals extraction from the polluted soils. [ABSTRACT FROM AUTHOR]

Sustainable management and development of forest sector should become an essential element in the strategy of prevention of the degradation of the land of each state. The forests play an important role in debts settlement of water courses, in ensuring the water quality, in maintaining land stability including the erosion control, landslides or avalanches. Forest exploitation represents a main source on degradation on the soil, having a major impact on the environment. Accelerated erosion caused by forest exploitation and soil degradation has become the main factor which limits the sustainable use of the soil. Through irrational forest exploitation, the nature of damage that occurs is ecological, social and economic. Forests are sours of other goods and services for society, such as processed wood and non-wood products, space of recreation, landscaping etc. The large number of sites affected as a result of the forest exploitation, emphasizes massive environmental risks and their existence without urgent action has a negative impact on human health and the environment. [ABSTRACT FROM AUTHOR]

Contaminated soils from former industrial sites need urgent measures of treatment in order to be used for other purposes. Because of the large spaces that industrial sites usually occupy, green technologies have to be chosen to treat the soil while protecting the environment. Phytoremediation is an environmentally friendly technology that uses plants to decontaminate soils. The main advantage is the low cost compared to other techniques and the main disadvantage is the time factor because phytoremediation requires long period of time to treat the polluted soil. This paper presents specific features that must be taken into consideration when planning and implementing phytoremediation projects. Pollutants concentration and soil properties limit the application of phytoremediation. A clean-up plan is prepared taking into consideration limiting factors and then the remediation measures are implemented. The project needs long-term monitoring to determine the quantity of contaminants in soils during its implementation. The main purpose is to provide a safe environment for humans' health while improving the ecological situation of the former industrial sites. [ABSTRACT FROM AUTHOR]

The influence of aeration of soils polluted with heavy metals by using Thiobacillus-type microorganisms was studied using soil samples contaminated with heavy metals (Cu 4074 - 7550 mgkg-1, Zn 5870 - 9310 mgkg-1, Cd 36-50 mgkg-1, Pb 15000 - 42890 mgkg-1), from Romplumb, Baia Mare. The variation of the metal concentration extracted by bioleaching and aerated bioleaching was monitored for 16 weeks. The soil samples treated by bioleaching (Cu: 9 - 53%; Zn: 9 - 62%; Cd: 9 - 24%. Pb: 31 - 71%) have obtained a lower efficiency than the soil samples treated by aerated bioleaching (Cu: 34 - 70%; Zn: 36 - 76%; Cd: 17 - 38%. Pb: 44 - 78%), but there are percentage differences between the two processes (Cu: 17 - 27%; Zn: 14 - 27%; Cd: 8 - 14%, Pb: 7 - 13%). [ABSTRACT FROM AUTHOR]

Composting is one of the most used biowaste recycling method. The paper highlights the influence of some natural organic additives such as cattle and poultry manure on the quality of compost and especially on the content in microelements and heavy metals. The mature compost showed the following macro and microelements concentrations: total N 1.12-1.38%, P 0.56-0.90%, K 0.68-0.92%, Ca 1.18-1.70%. Mg 0.38-0.66%. The compost that included cattle manure showed the highest content in humic substances, i.e. about 24.6%. The sequential analysis of metals revealed that the mobilisable sulphides had the largest share of the total content in metals, i.e. Pb 51.05% in the compost with cattle manure; Cd 55.78% in the compost with poultry manure, and As 48.92% in the vegetable compost without additives. The very low percentage of available metals for plant uptake proves the efficiency of the organic additives. [ABSTRACT FROM AUTHOR]

Knowledge of the basic levels of heavy metal concentrations in soil and their spatial disposition, on a certain area, is particularly important for economic activities, but especially for preventing and stopping pollution. The spatial distribution maps, obtained by measurements performed (of a certain density), cover the entire studied area and are very useful. According to the literature several methods are known for building such maps, most of them based on a simple mathematical interpolation. The Regression-Kriging method used in this paper is one of the best ways to solve this problem, because its algorithm takes into account the influence of physicochemical characteristics of the soil and also the deviations among the calculated values - using mathematical models - and the ones measured in the field. This method was used to perform the maps of the spatial distribution for eight heavy metals concentrations (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in the Cluj County soils. The use of the nonlinear mathematical models and the maps for predictors (previously achieved) have provided a high precision for these spatial distributions, that can be now successfully applied in preventing and combating of soil pollution. [ABSTRACT FROM AUTHOR]

Heavy metal pollution is an important issue worldwide and one of the technologies that can be sustainable in treating the contamination is phytoremediation. One of the plants that is known to tolerate heavy metals is Helianthus annuus. It can deal with heavy metals like Zn, Pb, Ni, Cr, Cd, Cu, As, Fe. In this study, our aim was to determine the plant's tolerance to copper and to investigate its influence on the germination of seeds and plant growth. The measurements and collection of data were made one week after establishing the seed germination test. We analysed which was the highest concentration of copper that the seeds of sunflower can tolerate and what is the effect at low and high concentrations. For a low concentration of copper, the germination rate was high, while a high concentration was toxic. We compared the root and shoot lengths and the fresh and dry weight of the plants to determine the effect of copper on the plant's development. Our investigation concluded that the highest seed copper tolerance of 90% was at 1 ppm concentration and it decreased significantly to 16% at the concentration of 10 ppm. At the highest concentrations the tolerance was low and the seeds had an abnormal development. [ABSTRACT FROM AUTHOR]

This paper presents the results of researches on the contamination and depollution of soil samples polluted with crude oil. The depollution was performed by repeatedly heating the soil samples at the constant temperature of 350 degrees C, and different times of keeping in the proposed installation: 5, 10 and 15 minutes. The initial quantity of the pollutant in the soil was 15321.6; 25113.6 and 79000 mg/kg of dried substance. At the end of these experiments, the results have revealed that the efficiency of thermal desorption was influenced by the duration of the treatment and the degree of contamination, obtaining a highly efficient decontamination process with efficiencies up to 99.85 %. [ABSTRACT FROM AUTHOR]

Hexachlorocyclohexane it's been used almost fifty years as a pesticide. 50's studies about its consequences to the environment revealed the serious damage it can create. The storage, disposal and utilization of Hexachlorocyclohexane as a pesticide generated environmental contamination with HCH. This is an overview of the methods used by different countries for the remediation of contaminated sites with hexachlorocyclohexane. The method used depends by soil's type, soil utilization, level of pollution, cost. The optimal results require experimental research, time, money and knowledge from a wide scientific area such us: chemistry, physics, engineering, etc. [ABSTRACT FROM AUTHOR]

The heritage of the past, when there wasn't much focus on complying with norms of good practice on the environment, has now become very visible on the sites found in the areas of industrial deposits. According to the information available at national level, there are 169 deposits for industrial waste which are subject to the provision of Directive 1999/31/EC32, covering a surface of around 2765 ha. In order to diminish the quantities of waste and the problems of their storage, it is recommended to review the technological processes and maximize the revaluation of the waste, as well as evacuating and storing it in a grouped manner, for the purpose of annihilating certain toxic effects. Without minimizing the importance of risks related to industrial waste storing, we must point out that, sometimes, the decisions of prevention/reduction of environmental risks are contrary to those of economic nature, which focus, most of all, on controlling factors affecting the production from the point of view of quantity and quality. The main directions with successful attempts of revaluation of industrial waste are: cement industry, asphalt industry and construction materials. [ABSTRACT FROM AUTHOR]

Our main goal was selecting a porous ceramic support for forming biofilm, used afterwards in the degradation of chlorinated solvents. The choice of support was achieved through "batch" reactors with closed circuit and through a continuous-circuit reactor at a temperature of 30 °C. Then a pilot plant was used consisting of four cylindrical glass columns filled with ceramic supports of different porosity. A microbial consortium growed and selected in advance from the groundwater of a contaminated site was introduced. Alternating during the experimental period, water with butane as the growth substrate, and water with O2 for aerobic conditions conformation, was added. Trichloroethylene used as the contaminant was introduced into the system continuously. Upon completion of the 100 days of experiment, Biomax ® porous support, proved to have the best results in the formation of biofilm realizing a high rate of pollutant degradation. [ABSTRACT FROM AUTHOR]

This paper presents a study conducted by the authors on the main indicators of fecal pollution of surface water and sediment. It is also made a description of the methods for the determination of microbiological fecal indicator bacteria. Coliforms bacteria or faecal coliforms, Escherichia coli microorganisms of the Enterobacteriaceae family and Enterococci (faecal streptococci) are part of the biological indicators of water quality. The spores belonging to the genus Clostridium are considered as microbiological indicators of sediments. In particular Clostridium perfringens has the characteristics of a microbiologic indicator of fecal pollution. [ABSTRACT FROM AUTHOR]

Developing the maps for based levels of heavy metal contents in European soils and the mobility maps of these pollutants is an activity of great significance in the fight to preventing and limiting the pollution phenomenon of soils. There are several mathematical methods for developing these maps of which the simplest is I.D.W. interpolation and the most complex is regression-kriging method. This latter method combines I.D.W. (Inverse Distance Weighting) interpolation with regression analysis, for this purpose, using a number of maps of predictors (environmental variables that influence the phenomenon studied). In case of heavy metals, the most important predictors are clay content, soil pH and organic matter content. The developing of maps for these three characteristics for Cluj county soils - using I.D.W. metho-was the subject of this paper. [ABSTRACT FROM AUTHOR]

The article presents the development of a mathematical model concerning thermal desorption in a tubular electric furnace, using the linear regression analysis principle. With a range of experimental data obtained from some laboratory tests on water evaporation plus pollutant (Hexaclorocyclohexane - HCH), evaporation resulting from the application of thermal desorption on some soil samples; a mathematical model was developed to calculate the mass of substance evaporated from the soil according to the two important parameters of the process, namely the temperature (T) and the duration of maintenance (τ) in the furnace. By numerical simulation, for values of temperature (T) of: 200 °C, 350 °C, 500 °C, 650 °C and maintenance time (τ) of 5, 10, 15 and 20 minutes, it was calculated the mass of evaporated substance. To validate the experimental model, the reproducibility dispersion of results and the concordance dispersion were calculated. Results show that there is a good concordance between the experimental data and data calculated using the mathematical model. [ABSTRACT FROM AUTHOR]

In the present paper is made a study on the ex-situ bioremediation methods, to determine the most adequate techniques of bioremediation for soils contaminated with petroleum products. Pollution with petroleum hydrocarbons, due primarily to the increase of oil and petroleum products consumption represents a major problem for the environment with serious repercussions for humans, plants and animals. Bioremediation is a biological, natural method, being successfully used in remediation of sites contaminated with petroleum hydrocarbons, without adversely affecting the ecosystem and having a relatively low cost. Bioremediation is based on the presence of indigenous microorganisms in the soil and on the introduction in the contaminated area with petroleum products of microorganisms capable of degrading pollutants. The degree of degradation of petroleum hydrocarbons is influenced by several factors, of which the most important are: temperature, pH, soil humidity, oxygen concentration, nutrient concentration, concentration and type of hydrocarbons. [ABSTRACT FROM AUTHOR]