During the construction of the new urban area in the north-eastern part of Stockholm, Stockholm Royal Seaport, groundwater with extremely elevated levels of the carcinogenic aromatic hydrocarbon benzene was discovered in the area Hjorthagen. Such a contamination can be remediated in-situ by the use of chemical oxidation and biodegradation. Due to the fact that many factors such as contaminant composition, groundwater characteristics and temperature vary between sites, smaller bench scale studies are usually conducted before the full scale remediation on site. Little published research exists on the ability of these remediation techniques in areas with lower groundwater temperature such as Stockholm, why the need of a bench-scale study in this case is even larger. The objective of this master thesis is to, out of three investigated remediation agents, find the most suitable one for remediation of the benzene-contaminated groundwater in Hjorthagen. This was made in the form of a bench-scale study and the techniques studied were chemical oxidation, for which the two agents hydrogen peroxide (uncatalyzed and catalyzed in the form of Fenton’s reagent) and persulfate (activated with iron (II)) were used, and biological degradation by the use of a calcium peroxide-based compound. The study showed that the benzene-contaminated groundwater was best remediated with Fenton’s reagent, which was able to degrade the benzene with great success.

In situ chemical oxidation (ISCO) using permanganate is a technology for treatment of organic hazardous wastes. This research is a review of 30 permanganate (MnO4-) ISCO sites to determine whether there are long term impacts on groundwater quality due to the introduction of the oxidant into the subsurface. A second objective is to determine if manganese concentration can be predicted by trends in specific pre and postoxidation monitored parameters (i.e., pH and oxidation reduction potential (ORP)). The final objective is to identify the effects of site and design conditions on groundwater conditions postoxidation. Results indicate that (1) there are limited long term groundwater impacts due to oxidant introduction (i.e., water quality indicators begin to approach preoxidation levels by 2 years postoxidation), (2) manganese concentrations can be predicted and (3) site and design conditions have pronounced short term impacts on geochemical parameters (i.e., especially site media type, mass of oxidant injected, and initial ORP).

This diploma thesis addresses the ICT employee evaluation methods in conjunction with their ICT roles. The objective of this work is to produce the lead-in for ICT managers, Human Resources staff etc. for creation of employee evaluation systems or motivation programs in the workplaces with high rate of ICT professions. The work strives to combine psychological and informatics insight to offer corresponding evaluation instruments for each ICT role.

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