Large offshore projects have been relying on effective risk management practices that are initiated during tender phases. These projects are characterized by high technical complexity, involve many project actors, and interface dependencies between them. As projects transition from tender to execution, the focus shifts to evolving operational risks, without seeing the contextual and underlying reasons behind it. Risk information and decision logic are often fragmented that contributes to reduced project performance. The financial influence is significant, as risk contingencies can account for 10-12% of total project value. While successfully exploited opportunities or omitted risks may not produce visible effects, insufficient risk treatment can result in adverse outcomes severe enough to reduce contractor profit margins. This thesis investigates how quality of project risk transfer and continuity can be improved during handover from tender to execution in offshore energy projects. This study has adapted a qualitative research design that combines literature review, two in-depth case studies of offshore energy projects executed by major marine contractor, Boskalis. Additionally, this research presents semi structured interviews with key stakeholders involved in the case study projects as well as actors in general of similar expertise working at the company. This analysis is guided by theoretical perspectives from Knowledge Management and Transition Management, that frames risk knowledge as both strategic organisational asset, and dynamic construct shaped by feedback loops, time delays and organisational interfaces. The findings indicate that risk transfer discontinuity is caused due to weakness in knowledge continuity and failure in bidirectional flow of information across project phases. The company demonstrates strong institutional capabilities and expertise in the field of risk engineering, tender and project management. So, it can also be said that continuity is not due to lack of tools, technical knowledge, or formal procedures. There are critical breakdowns during negotiation stages, planning handovers, and team transitions, where contextual reasoning, assumptions and tacit knowledge are not sufficiently transferred. This thesis concludes that improving risk transfer quality needs a shift in focus from static documentation of risk registers, towards managing transition moments, strengthening feedback mechanisms, and preserving common knowledge across organizational boundaries. Practical recommendations are proposed in the end, including targeted negotiation feedback gates, operational involvement in tendering, and adaptive practices to capture lessons learned.

This thesis evaluates the leaching characteristics and environmental impacts of conventional and rubberized porous asphalt mixtures subjected to tidal flooding conditions. Given the increasing vulnerability of coastal infrastructures to tidal floods exacerbated by climate change, the research investigates explicitly the release behavior of metals, metalloids, and anions from both crumb rubber-modified and conventional porous asphalt immersed in tap water and seawater. The study aims to provide insights into the environmental implications of utilizing crumb rubber, derived from recycled tires, in porous asphalt formulations, balancing its mechanical benefits against potential environmental risks.

Through systematic laboratory experiments, leachates from compacted cylindrical asphalt samples were collected and analyzed using Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES) for metals and Ion Chromatography (IC) for anions. The results demonstrate that crumb rubber significantly affects the leaching behavior of asphalt mixtures by acting as an adsorbent for several contaminants. Thus, generally reducing their leaching potential compared to conventional porous asphalt. However, elevated concentrations of certain elements, such as zinc, aluminum, and magnesium, originating from the crumb rubber itself, were observed, highlighting the complexity of the environmental behavior of these mixtures.

The research identifies critical differences in leachate release patterns between two different conditioning methods, with an initial rapid release of surface-bound contaminants followed by slower diffusion-controlled processes. Elements such as nickel and cadmium displayed unique delayed release behaviors, suggesting potential long-term environmental implications. Additionally, the study highlights the significant role of material composition, particularly tire-derived crumb rubber and structural additives, in influencing the leaching profiles.

The environmental risk assessment performed using the Heavy Metal Pollution Index (HPI) further emphasizes that crumb rubber-modified porous asphalt generally presents lower environmental risks compared to conventional mixtures. Nevertheless, specific metals and ions exceed regulatory thresholds, underscoring the importance of considering local environmental standards in the implementation
of these materials.

Overall, this research contributes valuable knowledge regarding the sustainable application of crumb rubber-modified porous asphalt in coastal regions. Recommendations for future studies include the investigation of long-term leachate dynamics under diverse environmental conditions and the exploration of effective mitigation strategies to enhance the ecological compatibility of asphalt pavements.