Life cycle assessment of soil remediation options:Study of options at Norrbyskär - which alternative has the least climate impact?  The purpose of this report was to make a life cycle assessment (LCA) to compare four suggested options for soil remediation at Norrbyskär, Umeå. The question formulation was to find out which option that had the least climate impact depending on the aim of the remediation. Main focus of the study was emissions of CO2 from transportation and machine work for each remediation option. The LCA was a screening and presented a good overview for the results. What sets the four remediation options apart is the amount of soil that is processed for each option. The LCA was performed according to the standards ISO 14040:2006 and ISO 14044:2006. Calculations in the report was performed with the LCA-software SimaPro and general data from EcoInvent. The results showed that the total emissions from each soil remediation option varied between 310 and 590 tonnes carbon dioxide equivalents (CO2e). The option that only included covering of the contaminated area with new soil had the least emissions and the option that included excavation and filling with new soil had the highest emissions. Both options do not fulfill the same goals in the end, though. One conclusion is that the more extensive remediation is the greater is the climate impact.

Nuclear power waste contains radioactive isotopes with long half lives and the problem lies in the fact that the lanthanides and actinides must be separated before the nuclear waste can be reprocessed. Transuranic Extraction (TRUEX), a liquid-liquid extraction method, has been developed but fails to separate the lanthanide and actinides and creates large volumes of liquid waste. It has been shown that attaching three CMPO (carbamoyl phosphine oxide) ligands used in the TRUEX process to a calixarene increases the separation and extraction efficiency of the system. The research goal is to attach the CMPO ligand to a polymer to make a membrane to be used in nuclear waste remediation. The triblock polymer system has been designed to have a cross-linking group to create the membrane structure, a solubilizing group to improve the flow of aqueous media through the membrane, and the CMPO ligand to chelate actinides. This paper describes the design of the polymer, its synthesis, and my research data. / text

The overall objective of the present study was to evaluate the effectiveness of using a variety of hydrophobic biopolymers and hydrophobic biopolymer-coated sands as technically and economically feasible in-situ sediment amendments or alternative capping materials on a laboratory scale. Cutin from tomato peels, cellulolytic enzyme lignin from sitka spruce chips, and keratin azure from commercially dyed sheeps wool were isolated, prepared, tested, and evaluated as feasible hydrophobic biopolymers for the removal of selected Polycyclic Aromatic Hydrocarbons (PAHs). Testing included chemical and physical characterization, as well as the measurement of kinetics and equilibrium sorption parameters for the sorbates naphthalene, phenanthrene, and pyrene as model hydrophobic organic contaminants. Tomato peel cutin exhibited the largest overall affinity for PAHs, however, keratin azure was selected for further evaluation as the most feasible material due to its low preparation cost. Amendment of industrial sand with a stable, uniform, cross-linked keratin azure derivative was achieved to produce hydrophobic biopolymer-coated sand products containing zero, moderate, and high mass fractions of sand. Chemical and physical material parameters, as well as kinetics and equilibrium sorption parameters for the sorbates naphthalene, phenanthrene, and pyrene, were then obtained for the coated sand products. This allowed simple finite difference modeling of PAH fate and transport through a thin cap comprised of the same, insight into the specific sorption mechanisms involved, and information which could prove useful in predicting potential of keratin products to provide a suitable capping material. Conclusions and recommendations for future research focus on the technical and economical feasibility of the prepared hydrophobic biopolymers and hydrophobic biopolymer-coated sand products as capping or in-situ sediment amendments. / text

The disposal of combustible wastes by incineration is a controversial issue that is strongly debated by both scientists and environmental activists due to the resulting emissions of noxious compounds, including (inter alia) polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), heavy metals and acid gases like sulfur dioxide. Currently available air pollution control devices are capable of effectively cleaning flue gases, and PCDD/F emissions to air from modern municipal solid waste (MSW) incinerators are low. However, the PCDD and PCDF end up in ash fractions that, in Sweden, are usually deposited in landfills. The European Union has recently set a maximum permitted total concentration of 15 µg TEQ/kg for PCDD/F species in waste. Fly ash from municipal solid waste (MSW) incineration containing PCDD/Fs at concentrations above this limit will have to be remediated to avoid disposing of them in landfills; an expensive and environmentally unfriendly option. Therefore, effective, reliable and cost-effective methods for degrading PCDD/F in fly ash are required, and a better understanding of the behavior of PCDDs and PCDFs during thermal treatment will be needed to develop them. In the studies this thesis is based upon both the formation and degradation of PCDDs and PCDFs in ashes from MSW incineration were studied. The main findings of the investigations regarding PCCD/F formation were: - The concentrations of PCDD and PCDF in fly ash increased with reductions in the temperature in the post-combustion zone. - The homologue profile in the ash changed when the temperature in the post-combustion zone changed. - The final amounts of PCDD and PCDF present were affected by their rates of both formation and degradation, and the mechanisms involved differ between PCDDs and PCDFs. The main findings from the degradation studies were: - The chemical composition of ash has a major impact on the degradation potential of PCDD and PCDF. - The presence of oxygen during thermal treatment can enhance the degradation of PCDD and PCDF. - Thermal treatment is a viable option for degrading PCDD and PCDF in ashes from MSW. - Shifts in chlorination degree occur during thermal treatment. - Rapid heat transfer into the ash is a key factor for ensuring fast degradation of PCDD and PCDF. - Degradation of other chlorinated organic compounds, e.g. PCB and HCB, also occurs during thermal treatment of ash. - Reductions in levels of PCDD and PCDF were not solely due to their desorption to the gas phase. - Differences between the behavior of 2378-substituted congeners of PCDD and PCDF and the other congeners during thermal treatment were observed. - Differences in isomer patterns of both PCDD and PCDF were observed between the ash and gas phases after thermal treatment at both 300 and 500 oC. Overall, the results show that the formation and degradation mechanisms of PCDDs differ substantially from those of PCDFs. Thus these groups of compounds should be separately considered in attempts to identify ways to reduce their concentrations.

To assess the long-term performance of soil-cement materials used in source-control remediation methods (i.e. cement-based solidification/stabilization), procedures to measure or estimate contaminant migration parameters are essential. Previous research indicates that diffusion may be an important mechanism in contaminant transport through soil-cement materials. However, there is a paucity of information regarding the diffusion of contaminants through these materials. The development of a single-reservoir diffusion apparatus and methodology to assess the effective diffusion coefficient (De) and effective porosity (ne) of dissolved, conservative, inorganic chemicals for saturated, cured, monolithic soil-cement specimens is discussed. This is the only study known to investigate these parameters for these materials. The results of tritiated water diffusion tests on 14 different soil-cement mixtures are presented and the influence of curing time and mixture properties such as water-to-cement ratio, cement content, and grain-size distribution are examined. Results suggest that, to determine reasonable assessments of the longer-term parameters, soil-cement samples should be cured for a minimum of 70 days before commencing diffusion testing. Values of ne (0.21 to 0.41) and De (2.50×10-10 m2/s to 7.0×10-10 m2/s) determined are similar to those previously determined for a number other low-hydraulic conductivity materials (i.e. saturated inactive clays). The water content of the initial mixture is shown to have a substantial effect on the diffusive properties as the results indicate that both the total porosity (n) and the effective porosity, ne, generally increase with increasing initial water content. For the range of soils used in this investigation, grain-size distribution did not have a substantial effect on the values of ne or De determined from diffusion testing. The adaptation of a double-reservoir diffusion testing apparatus and methodology to evaluate the distribution coefficient (Kd) and De of organic contaminants is also presented. This apparatus is used to evaluate Kd and De of benzene, ethylbenzene, naphthalene, and trichloroethylene for three soil-cement mixtures. Values of Kd (0 to 2.5 cm3/g depending on the compound and soil-cement mixture tested) determined from diffusion testing, batch testing, and theoretical estimates from the literature were in general agreement. Values of De for the organic compounds ranged from 1.50×10-10 to 3.0×10-10 m2/s.

This thesis proposes a strategy to capitalize on the abundance of derelict service stations in Vancouver, BC, as a means to address the current crisis of seniors’ housing and services. Vancouver’s glut of vacant service stations reflects a widespread trend of service station closures across North America. As former service stations, these sites are commonly contaminated and have to undergo remediation before they can be rezoned for other uses. However, this network of sites has great potential for long term development. The goal is to create an alternative to the homogeneous seniors’ home currently available and establish a network of ‘Community Stations’ spread throughout the city. These sites will act as nodes to provide housing and services for seniors in the local community. The design is a phased development which will allow time for the site to remediate as well as, through community involvement, establish value and ownership.

Innovative means and methods were tested to develop an economical, pragmatic and environmentally sustainable soil remediation process for heavy metal contaminated soils. An unsaturated-flow soil washing procedure was devised to dissolve the soil-bound toxic heavy metals; the latter were extracted by a chemical washing solution that percolated through the soil matrix. Subsequently, the leached toxic heavy metals were selectively concentrated, by a chemical precipitation process, into a solid waste. Thereby, a fraction of the spent ethylenediaminetetraacetic acid (EDTA), within the washing and rinsing leachate, was theoretically regenerated and recycle-ready. / The unsaturated-flow washing procedure was perfected by applying different treatments to a soil from a secure landfill. This soil was contaminated with Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, S and Zn. The major contaminants were Fe, Pb, Zn, S, Cu and Mn, making up 25, 1.9, 1.0, 0.4, 0.4 and 0.2%wt of the soil. The extraction responses of the contaminants and those of Al, Ca, Mg and P were established for citric acid (0.5 M) and different molarities of diammonium EDTA ((NH4)2EDTA). The DOW Chemical Company supplied the (NH4)2EDTA (i.e. VERSENE), a 1.37M industrial cleaner, which roughly costs $1.85kg-1 in bulk. The affordability of VERSENE was a pre-condition for hoping to satisfy the economical feasibility of remediating trace metal contaminated soils. / Ultimately, the developed unsaturated-flow washing procedure was tested in a pilot-scale experiment, for its ability to remediate a soil from an abandoned car battery recycling facility. The latter soil was severely contaminated with Pb (3.9%wt). Drip irrigation was used to apply (NH4) 2EDTA and water-rinsing solutions to the surface of soil heaps that rested atop an impermeable barrier, which permitted the retrieval of the leachate. A cumulative EDTA input to the soil of 10.6% wt extracted 49.4% of the total Pb content of the soil. Alternatively, readily biodegradable citric acid barely extracted 2.2% of the total Pb content of the soil, for a cumulative input of 18.1% weight of soil. Different treatments were tested for their effectiveness in concentrating the leached toxic heavy metals into a solid waste. The Pb was best precipitated with Na2S alone, as it provided the most concentrated solid toxic waste. / The environmental sustainability of remediating trace metal contaminated soils was thoroughly examined, as per the amounts of chemical entrants and toxic waste by-products, and per the post-treatment leaching of toxic levels of the remaining and potentially toxic trace metals. (Abstract shortened by UMI.)

Petroleum hydrocarbons (PHCs) such as gasoline are ubiquitous organic compounds present at contaminated sites throughout the world. Accidental spills and leakage from underground storage tanks results in the formation of PHC source zones that release hundreds of organic compounds, including the high impact, acutely toxic and highly persistent aromatics (e.g., benzene, toluene, ethylbenzene, xylenes, trimethylbenzenes and naphthalene) into groundwater. Contamination by these compounds continues to persist until the PHC source zone is treated in place or removed. In situ chemical oxidation (ISCO) employing persulfate was identified as a potentially viable technology for the treatment of PHC source zones. The effectiveness and efficiency and, therefore, the overall economic feasibility of a persulfate-based ISCO treatment system depend upon the reactivity of the target organic compounds and the interaction of persulfate with aquifer media. The objective of this research was to investigate the persistence of unactivated and activated persulfate in the presence of aquifer materials, and to examine persulfate oxidation of PHC compounds at both the bench- and pilot-scales. A series of bench-scale studies were performed to estimate persulfate degradation kinetic parameters in the presence of seven well-characterized, uncontaminated aquifer materials and to quantify the changes in specific properties of these materials. Batch experiments were conducted in an experimental system containing 100 g of solids and 100 mL of persulfate solution at 1 or 20 g/L. Column experiments were designed to mimic in situ conditions with respect to oxidant to solids mass ratio and were performed in a stop-flow mode using a 1 g/L persulfate solution. The degradation of persulfate followed a first-order rate law for all aquifer materials investigated. An order of magnitude decrease in reaction rate coefficients was observed for systems that used a persulfate concentration of 20 g/L as compared to those that used 1 g/L due to ionic strength effects. As expected, the column experiments yielded higher reaction rate coefficients than batch experiments for the same persulfate concentration due to the lower oxidant to solids mass ratio. Bench-scale data was used to develop a kinetic model to estimate the kinetic response of persulfate degradation during these tests. The push-pull tests involved the injection of persulfate (1 or 20 g/L) and a conservative tracer into a hydraulically isolated portion of the sandy aquifer at CFB Borden, Canada. The kinetic model developed from the bench-scale data was able to reproduce the observed persulfate temporal profiles from these push-pull tests. This implies that persulfate degradation kinetics is scalable from bench-scale to in situ scale, and bench tests can be employed to anticipate in situ degradation. The estimated reaction rate coefficients indicate that persulfate is a persistent oxidant for the range of aquifer materials explored with half lives ranging from 2 to 600 days, and therefore in situ longevity of persulfate will permit advective and diffusive transport in the subsurface. This is critical for successful delivery of oxidant to dispersed residuals in the subsurface. Activation of persulfate is generally recommended to enhance its oxidation potential and reactivity towards organic compounds. This approach may influence the stability of persulfate-activator system in the presence of aquifer materials. A series of batch tests were performed to investigate persistence of persulfate at two concentrations (1 or 20 g/L) using three contemporary activation strategies (citric acid chelated-ferrous, peroxide and high pH ) in the presence of 4 well-characterized, uncontaminated aquifer materials. Chelation by citric acid was ineffective in controlling the interaction between persulfate and Fe(II) and a rapid loss in persulfate concentration was observed. Higher Fe(II) concentration (600 mg/L) led to greater destabilization of persulfate than lower Fe(II) concentration (150 mg/L) and the persulfate loss was stoichiometrically equivalent to the Fe(II) concentration employed. Subsequent to this rapid loss of persulfate, first-order degradation rate coefficients (kobs) were estimated which were up to 4 times higher than the unactivated case due to the interaction with Fe(III) and CA. Total oxidation strength (TOS) was measured for peroxide activation experiments and was observed to decrease rapidly at early time due peroxide degradation. This was followed by slow degradation kinetics similar to that of unactivated persulfate implying that the initial TOS degradation was peroxide dominated and the long-term kinetics were dominated by persulfate degradation. The kobs used to capture TOS degradation for later time were shown to depend upon unactivated persulfate and peroxide degradation rate coefficients, and peroxide concentration. Either a slow peroxide degradation rate and/or higher peroxide concentration allow a longer time for peroxide and persulfate to interact which led to kobs ~1 to 100 times higher than kobs for unactivated persulfate. For alkaline activation, kobs were only 1 to 4 times higher than unactivated persulfate and therefore alkaline conditions demonstrated the least impact on persulfate degradation among the various activation strategies used. For all activation trials, lower stability of persulfate was observed at 1 g/L as compared to 20 g/L due to insufficient persulfate and/or ionic strength effects. A series of batch reactor trials were designed to observe the behavior of the nine high impact gasoline compounds and the bulk PHC fraction measures subjected to various persulfate activation strategies over a 28-day period. This bench-scale treatability used unactivated persulfate (1 or 20 g/L) and activated persulfate (20 g/L). Activation employed chelated-Fe(II), peroxide, high pH or two aquifer materials as activators. No significant oxidation of the monitored compounds was observed for unactivated persulfate at 1 g/L, but 20 g/L persulfate concentration resulted in their near-complete oxidation. Oxidation rates were enhanced by 2 to 18 times by activation with peroxide or chelated-Fe(II). For alkaline activation, pH 11 trials demonstrated ~2 times higher oxidation rates than the unactivated results. For pH 13 activation the oxidation rates of benzene, toluene and ethylbenzene were reduced by 50% while for the remaining monitored compounds they were enhanced by 5 to 100%. Natural activation by both aquifer materials produced oxidation rates similar to the unactivated results, implying that either activation by minerals associated with aquifer material was not significant or that any potential activation was offset by radical scavenging from aquifer material constituents. Acid-catalyzation at pH <3 may enhance oxidation rates in weakly buffered systems. Oxidation of the monitored compounds followed first-order reaction kinetics and rate coefficients were estimated for all the trials. Overall, activated and unactivated persulfate appear to be suitable for in situ treatment of gasoline. Persulfate under unactivated or naturally activated conditions demonstrated significant destruction of gasoline compounds and showed higher persulfate persistence when in contact with aquifer solids as compared to chelated-Fe(II) or peroxide-activated persulfate systems. This observation was used as the basis for selecting unactivated sodium persulfate for a pilot-scale treatment of gasoline-contaminated source zone at CFB Borden, Canada where a ~2000 L solution of persulfate (20 g/L) was injected into a PHC source zone. Concentration of organics and inorganics were frequently monitored over a 4 month period across a 90 point monitoring fence line installed down-gradient. Treatment performance was measured by estimating organic and inorganic mass loading across the monitoring fence. Increased mass loading for sodium was observed over time as the treatment volume moved across the fence-line indicating transport of the inorganic slug created upon oxidant injection. The mass loading also increased for sulfate which is a by-product generated either due to persulfate degradation during oxidation of organic compounds or during its interaction with aquifer materials. Oxidation of organic compounds was evident from the enhanced mass loading of dissolved carbon dioxide. More importantly, a significant (45 to 86%) decrease in mass loading of monitored compounds was observed due to oxidation by injected persulfate. The cumulative mass crossing the monitoring fence-line was 20 to 50% lower than that expected without persulfate treatment. As the inorganic slug was flushed through the source zone and beyond the monitoring fence, the mass loading rate of sodium, sulfate and carbon dioxide decreased and approached background condition. Mass loading of the monitored compounds increased to within 40 to 80% of the pre-treatment conditions, suggesting partial rebound. These investigations assessed the impact of activation on persulfate persistence and treatability of gasoline and served to establish guidelines for anticipating field-scale persulfate behavior under similar conditions. In summary, unactivated persulfate is a stable oxidant in the presence of aquifer materials and its persistence depends upon TOC and Fe(Am) content of the materials, ionic strength, and aquifer to solids mass ratio. Persulfate exhibits significant destruction of gasoline compounds and can be employed for the remediation of gasoline-contaminated sites. Peroxide and chelated-Fe(II) enhance oxidation rates of these compounds, but reduce stability of the persulfate-activator system. Persulfate activation using high pH conditions does not significantly impact persulfate persistence but reduces the overall destruction of gasoline compounds. Therefore, activation imposes a trade-off between enhanced oxidation rates and reduced persulfate persistence. Kinetic model is representative of persulfate degradation at bench- and pilot-scales and can be used for estimation of in situ degradation. The quantification of oxidation rates for gasoline compounds under activated and unactivated persulfate conditions will assist decision-making for identification of appropriate remediation options when targeting contamination by gasoline or by specific high impact gasoline compounds. While persulfate oxidation resulted in partial treatment of a small gasoline source zone, aggressive persulfate load will be required during injection for a complete clean-up. Overall, persulfate-based in situ chemical oxidation was demonstrated to be an effective and a viable technology for the remediation of contaminated soil and groundwater.

Degassing and in situ formation of a mobile gas phase takes place when an aqueous phase equilibrated with a gas at a pressure higher than the subsurface pressure is injected in water-saturated porous media. This process, which has been termed supersaturated water injection (SWI), is a novel and hitherto unexplored means of introducing a gas phase into the subsurface. Herein is a first macroscopic account of the SWI process on the basis of continuum scale simulations and column experiments with CO2 as the dissolved gas. A published empirical mass transfer correlation (Nambi and Powers, Water Resour Res, 2003) is found to adequately describe the non-equilibrium transfer of CO2 between the aqueous and gas phases. Remarkably, the dynamics of gas-water two-phase flow, observed in a series of SWI experiments in homogeneous columns packed with silica sand or glass beads, are accurately predicted by traditional two-phase flow theory which allows the corresponding gas phase relative permeability to be determined. A key consequence of the finding, that the displacement of the aqueous phase by gas is compact at the macroscopic scale, is consistent with pore scale simulations of repeated mobilization, fragmentation and coalescence of large gas clusters (i.e., large ganglion dynamics) driven entirely by mass transfer. The significance of this finding for the efficient delivery of a gas phase below the water table in relation to the alternative process of in-situ air sparging and the potential advantages of SWI are discussed. SWI has been shown to mobilize a previously immobile oil phase in the subsurface of 3-phase systems (oil, water and gas). A macroscopic account of the SWI process is given on the basis of continuum-scale simulations and column experiments using CO2 as the dissolved gas and kerosene as the trapped oil phase. Experimental observations show that the presence of oil ganglia in the subsurface alters gas phase mobility from 2-phase predictions. A corresponding 3-phase gas relative permeability function is determined, whereas a published 3-phase relative permeability correlation (Stone, Journal of Cana Petro Tech, 1973) is found to be inadequate for describing oil phase flow during SWI. A function to predict oil phase relative permeability is developed for use during SWI at high aqueous phase saturations with a disconnected oil phase and quasi-disconnected gas phase. Remarkably, the dynamics of gas-water-oil 3-phase flow, observed in a series of SWI experiments in homogeneous columns packed with silica sand or glass beads, are accurately predicted by traditional continuum-scale flow theory. The developed relative permeability function is compared to Stone’s Method and shown to approximate it in all regions while accurately describing oil flow during SWI. A published validation of Stone’s Method (Fayers and Matthews, Soc of Petro Eng Journal, 1984) is cited to validate this approximation of Stone’s Method.

Laurence Sterne’s The Life and Opinions of Tristram Shandy, Gentleman, has been noted as an unconventional eighteenth-century novel and it has long been considered unadaptable and unfilmable. In the last decade, however, two popular adaptations of Tristram Shandy have appeared in new media forms: Martin Rowson’s 1996 graphic novel and Michael Winterbottom’s 2005 film. Since Sterne’s text denies the kind of transfer typical of literary adaptations, Rowson and Winterbottom adapt the conceptual elements. Through adaptation and media theory, this thesis defines the Shandean elements of Sterne’s novel and locates the qualities of the text retained in adaptation. Rowson and Winterbottom adapt the conceptual properties of Tristram Shandy, ‘the spirit of the text,’ into two distinct mediums. In an exploration of the conventions of each medium, this thesis argues that the adaptations of Tristram Shandy are true to its spirit, and both successfully adapt the unadaptable novel.