Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 160-168). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 160-168). Also available on the Internet.

Thesis (Ph.D.) in Ecology and EnviroNmental Sciences--University of Maine, 2002. / Includes vita. Bibliography: leaves 219-247.

Toxic metals contaminate soil worldwide and thus serve as sever environmental threat. Therefore the purposes of this study were to investigate in which soil fractions that different heavy metals (Fe, As, Cu, Zn and Pb) could be found in contaminated soils and if it is possible to use sieving as a method for decontamination. Soil samples were collected from three different locations, the Nasa silver mine, the Blaiken-mine and Svalget environmental station. The samples were oven dried and later on sieved into six different fractions 8mm, 4 mm, 0.5 mm, 0.250mm, 0.063 mm and <0.063 mm. The fractions 4 mm, 0.5 mm and <0.063 mm from each location were analyzed in an x-ray fluorescence detector. The results showed that in general the smallest fractions contained the highest concentration of heavy metals which was very clear for Pb where 5 out of 6 samples had the highest concentration in the smallest fraction. The highest concentration of Cu (1147 ppm) and Zn (1117 ppm) were found in the smallest fraction in samples from the location Svalget. The highest concentration of Pb (10042 ppm) was also found in the smallest fraction in samples from Blaiken. In similarity the highest concentration of As (13305 ppm) was found in the smallest fraction in samples from the Nasa mine. However, in most samples the difference between the smallest fractions and the coarser material was small. Sieving may therefore not be the best way to decontaminate soil because even the larger fractions contained high concentrations of heavy metals.

No description available.

Σκοπός της παρούσας εργασίας είναι η εκτίμηση των περιβαλλοντικών συνθηκών στο Νομό Χαλκιδικής όσον αφορά τα Βαρέα Μέταλλα. Αυξημένες συγκεντρώσεις βαρέων μετάλλων εντοπίζονται ΒΑ του Νομού Χαλκιδικής λόγω της μεταλλευτικής δραστηριότητας. Η ποιότητα του περιβάλλοντος καθορίζεται από την γεωχημεία της περιοχής (λόγω της θειούχου μεταλλοφορίας) και από τον τρόπο που ασκήθηκε η μακρόχρονη δραστηριότητα στο παρελθόν, με τις μεθόδους εξόρυξης και τη συσσώρευση μεταλλευτικών υλικών χωρίς κανένα μέτρο προστασίας. Επίσης, δυτικά του Νομού Χαλκιδικής σημειώνονται αυξημένες συγκεντρώσεις Αρσενικού λόγω του γεωθερμικού πεδίου. / The main purpose of the dissertation is the estimation of the environmental conditions in the prefecture of Halkidiki, regarding the heavy metals. In the North East area of Halkidiki there are observed increasing concentrations of heavy metals because of the high metal activity of the area. The quality of the environment is determined from the geochemistry of the area (because of the sulfur ore) and from the way that the metal activity is implemented in the area, with the excavation methods that took place in the mining and the concentration of metal materials without specific protection measures. Also, in the West area of Halkidiki it is observed that the limit of arsenic in the ground and in the surface and underground waters has been exceed because of the geothermic field.

No description available.

No description available.

Urban development leads to increased impermeable landscapes that interrupt the hydrological cycle by creating an impermeable barrier to the natural infiltration of precipitation. Precipitate, unable to infiltrate, flows over impermeable surfaces as sheet runoff, carrying the pollutants from the land with it; thus comprising the quality of the stormwater. The runoff is redirected (frequently untreated) to nearby waterways altering their water quality and quantity, thereby, adversely affecting receiving aquatic ecosystems. Suspended solids and elevated heavy metal concentrations in stormwater are the leading causes of water quality degradation in urban waterways in New Zealand. It is widely reported that vehicles and metal roofs are a major direct source of the key pollutants (total suspended solids (TSS) and heavy metals) in stormwater runoff; however, the contribution of atmospheric deposition, as an indirect source, in stormwater runoff is rarely considered. This is principally due to the many uncertainties and challenges with measuring and managing these pollutants in stormwater runoff. Therefore, a monitoring programme into the dynamics controlling atmospherically derived pollutant build-up and wash-off from urban surfaces was conducted. In particular, this research focused on the spatial and temporal variability of Cu, Zn, Pb, and TSS deposition in different land-use areas; the influence of pavement type on atmospherically-deposited pollutant loads in stormwater; and the contribution of wet deposition and dry deposition to the total deposition loads. Impermeable concrete boards (≈ 1 m2) were deployed for 11 months in different land-use areas (industrial, residential and airside) in Christchurch, New Zealand, to capture spatially distributed atmospheric deposition loads in runoff over varying meteorological conditions. Mixed-effect regression models were developed to explain the influence of different meteorological characteristics on pollutant build-up and wash-off dynamics. Next, impermeable asphalt, permeable asphalt, impermeable concrete, and permeable concrete boards were deployed for two months in a residential land-use area to determine the influence of pavement composition and roughness on pollutant loads in stormwater. Finally, wet deposition samples were analysed in an industrial land-use area for 8 months to monitor the contribution of wet deposition to atmospherically-deposited pollutant loads. All samples were analysed for total and dissolved Cu, Zn, Pb, and TSS. Pavement type: Results showed that both impermeable and permeable concrete were efficient at retaining Cu and Zn. Bitumen leaching from the impermeable asphalt was a significant source of Zn to runoff. However, bitumen leaching from the permeable asphalt did not contain elevated Zn loads. Infiltrate from the permeable asphalt provided little/no removal of Cu and Zn. Impermeable asphalt provided greater retention of TSS and Pb over impermeable concrete because its rougher surface entrapped more particulates. TSS and Pb loads were the lowest from the permeable pavements due to the pavers filtering out particulates. Spatial variability: Results showed that all three land-use areas exhibited similar patterns of varying metal and TSS loads, indicating that atmospherically-deposited metals and TSS had a homogenous distribution within the Christchurch airshed. This suggested that the pollutants originated from a similar source and that the surrounding land-use was not an important factor in determining atmospheric pollutant loads to stormwater runoff. Although, higher pollutant loads were found for the industrial area, this was attributed to local topographic conditions rather than land-use activity. Temporal variability: Results illustrated the importance of antecedent dry days on pollutant build-up. Peak rainfall intensity and rain duration had a significant relationship with TSS and Pb wash-off; rain depth had a significant relationship with Cu and Zn wash-off. This suggested that the pollutant speciation phase plays an important role in surface wash-off. Rain intensity and duration influenced particulate pollutants, whereas, rain depth influenced dissolved pollutants. Additionally, mixed-effect models could predict approximately 53-69% of the variation in airborne pollutant loads in runoff. Deposition pathways: Wet deposition was an important contributor of dissolved Zn to stormwater runoff. However, dry deposition was the greatest source of total Cu, Zn, and Pb loads in stormwater runoff. This is principally due to the low annual rainfall in Christchurch limiting pollutant removal via wet deposition unlike dry deposition, which is continually occurring. Understanding the dynamics of airborne pollutant deposition and their contribution to stormwater pollution could help stormwater managers in strategic decision-making processes such as choice of location and installation of different treatment systems.

No description available.