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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Bioavailability of polycyclic aromatic hydrocarbons in soils : mechanisms, consequences and means of assessment

Reid, Brian John January 2000 (has links)
No description available.
2

Kartering av markföroreningar inom Skutskärs Bruk samt utvärdering av spridningsrisker enligt Naturvårdsverkets MIFO fas 2

Lundell, Lisa January 2005 (has links)
<p>With the prospect of future construction on the Skutskär Pulp Mill property, Stora Enso Fine Paper has initiated an investigation of soil contaminants and a risk assessment of these contaminants. A soil and groundwater investigation has therefore been conducted on an open area of about 16 000 square meters, situated between the current wood room and digester house. To be able to integrate this study into an investigation for the whole industrial property, the study has been carried out as a phase 2 study according to the Swedish Environmental Protection Agency’s Methods of Inventories of Contaminated sites (MIFO).</p><p>The site investigation has involved soil and groundwater sampling, together with the analysis of heavy metals and organic contaminants. The degree of hazard posed by the contaminants, the level of contamination, the potential for migration of the contaminants, as well as the degree to which protection of human health and the environment is required in the area, have been weighed together for an overall risk assessment of the area with regard to human health and the environment.</p><p>The investigated area was built up by filling in the coastal waters. The fill material consists mainly of sand that becomes finer below the groundwater surface at the depth of about 2.3 m.</p><p>Above the groundwater surface pyrite cinders was encountered. Underneath the cinders, lime sludge, bark and wood fiber were found at different depths. The deepest layer encountered consists of moraine.</p><p>The results showed that most of the heavy metals in the soil originate from the pyrite cinders. The level of contamination was assessed as very high for Zn, Pb, Cu, Cd and Hg. In the groundwater, the level of contamination was assessed as high for Al and moderate for Pb and Cr. The level of organic contaminants was in general low. Heavy oils were encountered in shallow soil layers. Mercury was analysed due to risk of migration from an earlier factory that produced chlorine alkali. The metal was encountered in both the shallow and the deeper layers of soil. Only three of 56 soil samples exceeded the Swedish Environmental Protection Agency’s guideline value for less sensitive land use of 7 mg Hg/kg dry weight.</p><p>The investigation indicates that the metals still are bound to the pyrite cinders and that most of the leachable parts were mobilized during the years when the ground was not covered with asphalt.</p><p>Most of the contaminant migration is assumed to take place through groundwater advection. The groundwater flows in the direction of the dock and was calculated to about 3 m3 per day. The gradient in the area is about 0.5 %. The average linear groundwater velocity was computed to about 5 m per year. The transport of the pollutants might be slower due to adsorption and precipitation. Groundwater sampling indicates that the transport to the dock is up to 100 g Zn, 10 g Cr, 8 g Pb and 0.02 g Hg per year.</p><p>The site was assigned to risk class 3, i.e. moderate risk regarding human health and environment and relatively low urgency concerning additional investigations.</p> / <p>Inför framtida ombyggnationer inom industrifastigheten vill Skutskärs Bruk, Stora Enso, kartlägga markföroreningar och utvärdera vilken spridningsrisk de utgör. En undersökning av mark- och grundvattenförhållanden har därför utförts på en ca 16 000 m2 stor yta, belägen mellan dagens renseri och kokeri. Undersökningen har utförts enligt Naturvårdsverkets Metodik för Inventering av Förorenade Områden (MIFO) för att i framtiden kunna integreras i en fas 2- undersökning för hela fastigheten.</p><p>Arbetet har inneburit provtagning av mark- och grundvatten som analyserats med avseende på tungmetaller och organiska föroreningar. Föroreningarnas farlighet, föroreningsnivån, spridningsförutsättningarna samt objektets känslighet och skyddsvärde har vägts samman för att bedöma områdets risk för människors hälsa och miljö.</p><p>Området utgörs av utfylld havsbotten. Massorna består främst av sand som blir siltigare under grundvattenytan på ca 2,3 m djup under markytan. Ovan grundvattenytan påträffades kisaska. Därefter hittades mesa, bark och träfiber på varierande djup. Fyllningen underlagras av morän.</p><p>Resultatet visade att huvuddelen av tungmetallerna i marken härstammade från kisaskan. Föroreningsnivån bedömdes som mycket stor för Zn, Pb, Cu, Cd och Hg. I grundvattnet bedömdes föroreningsnivån som stor för Al och måttlig för Pb och Cr. Halten organiska föroreningar var generellt sett låg. Tyngre oljor påträffades i ytliga marklager.</p><p>Kvicksilver har analyserats eftersom risk för spridning från en före detta kloralkalifabrik uppströms området förelåg. Ämnet påträffades både i ytnära marklager och på större djup. Endast tre av 56 markprover översteg Naturvårdsverkets gränsvärde för mindre känslig markanvändning på 7 mg/kg TS.</p><p>Undersökningen tyder på att metallerna fortfarande är bundna till kisaskan och att stora delar av den lakbara delen transporterades bort under de år som ytan var oasfalterad.</p><p>Huvuddelen av föroreningstransporten antas ske genom advektion. Grundvattnet flödar i riktning mot hamnbassängen och beräknas uppgå till ca 3 m3/dygn. Områdets gradient är ca 0,5 %. Vattenpartiklarnas hastighet beräknades till ca 5 m/år. Föroreningstransporten kan vara lägre på grund av adsorption och utfällning. Grundvattenprovtagningen tyder på att den årliga transporten till hamnbassängen skulle kunna uppgå till 100 g Zn, 10 g Cr, 8 g Pb och 0,02 g Hg.</p><p>Objektet bedömdes tillhöra riskklass 3, det vill säga måttlig risk för människa och miljö samt relativt låg angelägenhet för vidare undersökningar.</p>
3

Kartering av markföroreningar inom Skutskärs Bruk samt utvärdering av spridningsrisker enligt Naturvårdsverkets MIFO fas 2

Lundell, Lisa January 2005 (has links)
With the prospect of future construction on the Skutskär Pulp Mill property, Stora Enso Fine Paper has initiated an investigation of soil contaminants and a risk assessment of these contaminants. A soil and groundwater investigation has therefore been conducted on an open area of about 16 000 square meters, situated between the current wood room and digester house. To be able to integrate this study into an investigation for the whole industrial property, the study has been carried out as a phase 2 study according to the Swedish Environmental Protection Agency’s Methods of Inventories of Contaminated sites (MIFO). The site investigation has involved soil and groundwater sampling, together with the analysis of heavy metals and organic contaminants. The degree of hazard posed by the contaminants, the level of contamination, the potential for migration of the contaminants, as well as the degree to which protection of human health and the environment is required in the area, have been weighed together for an overall risk assessment of the area with regard to human health and the environment. The investigated area was built up by filling in the coastal waters. The fill material consists mainly of sand that becomes finer below the groundwater surface at the depth of about 2.3 m. Above the groundwater surface pyrite cinders was encountered. Underneath the cinders, lime sludge, bark and wood fiber were found at different depths. The deepest layer encountered consists of moraine. The results showed that most of the heavy metals in the soil originate from the pyrite cinders. The level of contamination was assessed as very high for Zn, Pb, Cu, Cd and Hg. In the groundwater, the level of contamination was assessed as high for Al and moderate for Pb and Cr. The level of organic contaminants was in general low. Heavy oils were encountered in shallow soil layers. Mercury was analysed due to risk of migration from an earlier factory that produced chlorine alkali. The metal was encountered in both the shallow and the deeper layers of soil. Only three of 56 soil samples exceeded the Swedish Environmental Protection Agency’s guideline value for less sensitive land use of 7 mg Hg/kg dry weight. The investigation indicates that the metals still are bound to the pyrite cinders and that most of the leachable parts were mobilized during the years when the ground was not covered with asphalt. Most of the contaminant migration is assumed to take place through groundwater advection. The groundwater flows in the direction of the dock and was calculated to about 3 m3 per day. The gradient in the area is about 0.5 %. The average linear groundwater velocity was computed to about 5 m per year. The transport of the pollutants might be slower due to adsorption and precipitation. Groundwater sampling indicates that the transport to the dock is up to 100 g Zn, 10 g Cr, 8 g Pb and 0.02 g Hg per year. The site was assigned to risk class 3, i.e. moderate risk regarding human health and environment and relatively low urgency concerning additional investigations. / Inför framtida ombyggnationer inom industrifastigheten vill Skutskärs Bruk, Stora Enso, kartlägga markföroreningar och utvärdera vilken spridningsrisk de utgör. En undersökning av mark- och grundvattenförhållanden har därför utförts på en ca 16 000 m2 stor yta, belägen mellan dagens renseri och kokeri. Undersökningen har utförts enligt Naturvårdsverkets Metodik för Inventering av Förorenade Områden (MIFO) för att i framtiden kunna integreras i en fas 2- undersökning för hela fastigheten. Arbetet har inneburit provtagning av mark- och grundvatten som analyserats med avseende på tungmetaller och organiska föroreningar. Föroreningarnas farlighet, föroreningsnivån, spridningsförutsättningarna samt objektets känslighet och skyddsvärde har vägts samman för att bedöma områdets risk för människors hälsa och miljö. Området utgörs av utfylld havsbotten. Massorna består främst av sand som blir siltigare under grundvattenytan på ca 2,3 m djup under markytan. Ovan grundvattenytan påträffades kisaska. Därefter hittades mesa, bark och träfiber på varierande djup. Fyllningen underlagras av morän. Resultatet visade att huvuddelen av tungmetallerna i marken härstammade från kisaskan. Föroreningsnivån bedömdes som mycket stor för Zn, Pb, Cu, Cd och Hg. I grundvattnet bedömdes föroreningsnivån som stor för Al och måttlig för Pb och Cr. Halten organiska föroreningar var generellt sett låg. Tyngre oljor påträffades i ytliga marklager. Kvicksilver har analyserats eftersom risk för spridning från en före detta kloralkalifabrik uppströms området förelåg. Ämnet påträffades både i ytnära marklager och på större djup. Endast tre av 56 markprover översteg Naturvårdsverkets gränsvärde för mindre känslig markanvändning på 7 mg/kg TS. Undersökningen tyder på att metallerna fortfarande är bundna till kisaskan och att stora delar av den lakbara delen transporterades bort under de år som ytan var oasfalterad. Huvuddelen av föroreningstransporten antas ske genom advektion. Grundvattnet flödar i riktning mot hamnbassängen och beräknas uppgå till ca 3 m3/dygn. Områdets gradient är ca 0,5 %. Vattenpartiklarnas hastighet beräknades till ca 5 m/år. Föroreningstransporten kan vara lägre på grund av adsorption och utfällning. Grundvattenprovtagningen tyder på att den årliga transporten till hamnbassängen skulle kunna uppgå till 100 g Zn, 10 g Cr, 8 g Pb och 0,02 g Hg. Objektet bedömdes tillhöra riskklass 3, det vill säga måttlig risk för människa och miljö samt relativt låg angelägenhet för vidare undersökningar.
4

Bioaccessibility of metals in Toronto city parks

Dakane, Abdulkadir 18 December 2012 (has links)
The purpose of this work was to estimate metals bioaccessibility in soil samples from 15 city parks in Toronto, Ontario, Canada. Total metals concentrations were analyzed to identify contaminants that exceeded the Canadian Council of Ministers of the Environment (CCME) guidelines for residential/parkland use. Arsenic, barium, cadmium, cobalt, copper, lead, nickel and zinc were of particular interest as they have been known to have major effects on human health. Metal concentrations were below the CCME guidelines except for lead at three of the parks. Lead, copper and cadmium bioaccessibility in the soil samples as determined by an in-vitro physiologically based extraction test (PBET) were relatively high. Based on linear regression analyses there were no significant relationships between total metals and soil properties such as pH and total organic carbon (TOC). Generally there was negative correlation between metal bioaccessibility and TOC and positive correlation between bioaccessibility and soil pH.
5

Significance of Nondetects in the Mapping of Soil contaminants.

Zhang, Hongyu January 2013 (has links)
In the sample data of soil contaminants, the existence of nondetects is a common phenomenon. Due to their small values, they are always ignored. However, they form an essential part of the sample distribution and arbitrary changes of their values will affect the properties of the distribution, for example, the 95% upper confidence limit of the mean (95UCLM), which is an important index in risk assessment, is strongly related with the sample distribution. Statistical analysis methods for nondetects involve substitution by half of the detection limit (DL/2), maximum likelihood estimation (MLE), Kaplan-Meier and regression on ordered statistics (ROS). The significance of nondetects was examined in this study. Two large data sets of cadmium (Cd) and mercury (Hg) containing censored observations in Annedal’s park were used, where the censored observations were known from the laboratory. Large data sets were subsampled into small data sets with different sample sizes and censoring levels. The 95UCLM value of each data set was calculated by use of the statistical software ProUCL 4.1.00. Through comparison, it was found that in most cases the 95UCLM value calculated with lab values was lower than that of the censored observation for each data set. The difference in 95UCLM values between the data set with nondetects and the data set with lab values varied in each sample and was found to be related to sample size and to the censoring level. The higher the censoring level was, the bigger the 95UCLM value difference became. Either too small or too large a sample size would reduce the difference between the 95UCLM values. This result helps in certain cases, when the 95UCLM value of the sample data is a little lower than the threshold; using the lab values instead of nondetects to recalculate the 95UCLM value may supply a manageable and economic tool to classify the contaminated area.
6

Soil Fertility Status and Degradation of 2, 4, 6-Trinitrotoluene Contaminated Soils

Katseanes, Chelsea Kae 01 March 2014 (has links) (PDF)
Current models for predicting the environmental fate of munitions constituents (MC) in soils are based mostly on chemical distribution parameters and neglect the larger considerations of other soil parameters. We are working towards a new approach based on the whole soil activity for predicting the long-term residence time and fate of MC in soils with connection to agronomic soil fertility concepts. These relationships are demonstrated by correlating experiments involving full physical and chemical characterization of eight taxonomically distinct soils, with batch reactor studies determining MC degradation potential. Soils were incubated in a slurry for 10 days in a closed reactor system with temperature, pH, and Eh readings recorded every 24 h. Air and slurry samples were taken eight times within the 168 h incubation period. Carbon dioxide, TNT, and nutrient solution concentrations were assessed to obtain a full picture of soil chemistry changes associated with microbial activity in response to additions of TNT. Multivariate analysis was used to determine the main factors impacting degradation rate. Principle Components Analysis (PCA) statistically classified the soils based on the variance of their soil property data. Partial Least Squares Analysis (PLS) showed that TNT degradation was possibly correlated with soil fertility characteristics. Although this is an exploratory study, results show promise in moving towards a more effective way of predicting TNT environmental fate in soils.
7

Managing Soils For Environmental Science And Public Health Applications

Obrycki, John F. 21 December 2016 (has links)
No description available.

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