No abstract

Flow visualization using fluorescent microparticles and cell viability investigations are carried out to examine the mechanisms by which cells are seeded into scaffolds driven by surface acoustic waves. The former consists of observing both the external flow prior to the entry of the suspension into the scaffold and the internal flow within the scaffold pores. The latter involves micro-CT (computed tomography) scans of the particle distributions within the seeded scaffolds and visual and quantitative methods to examine the morphology and proliferation ability of the irradiated cells. The results of these investigations elucidate the mechanisms by which particles are seeded, and hence provide valuable information that form the basis for optimizing this recently discovered method for rapid, efficient, and uniform scaffold cell seeding. Yeast cells are observed to maintain their size and morphology as well as their proliferation ability over 14 days after they are irradiated. The mammalian primary osteoblast cells tested also show little difference in their viability when exposed to the surface acoustic wave irradiation compared to a control set. Together, these provide initial feasibility results that demonstrate the surface acoustic wave technology as a viable seeding method without risk of denaturing the cells.

Through asset lifecycle, data is collected for a variety of purposes across multiple disciplines, and exists in various formats and repositories. Decommissioning projects utilize and repurpose a multitude of these datasets; from use in analysis and planning, to facilitating systematic environmental assessments, and meaningful discussion with stakeholders. The key challenge is how do we consolidate historical data, incorporate new data, and make it evergreen to support planning and informed decision making; and how do we coordinate large volumes of previously disparate data in a meaningful way for all users with a simple access model? A team of geographic information system (GIS) practitioners and subject matter contacts in technical and health, safety and environment (HSE) disciplines was convened to collect, sort, and compile known historical offshore data, including, but not limited to; pipeline and structural inspections and environmental studies, all captured via Remote Operated Vehicle (ROV), Side Scan Sonar (SSS), and sampling programs. Data was reformatted to standardize headers and attributes allowing for merging of existing like-data and to support new data integration. To this end, we also worked collaboratively with vendors to optimize data collection and improve alignment with our internal data structures. The Esri GIS technology was utilized for data integration, specifically the web and mobile environments. Through these environments, non-GIS users could easily access data and focused applications, supporting ease of data visualization and allowing for a single view of data spanning decades and covering multiple themes. This enabled an enhanced understanding of the offshore environment, allowing us to identify gaps and focus areas for future data capture, helping to facilitate cross-discipline discussions, and identification of operational synergies; improving access, efficiency, and reducing decommissioning costs. Data integration resulting from this initiative and delivery through a spatially aware GIS environment is providing unprecedented access to a vast scope of cross-disciplinary data previously not possible with more traditional engineering methods and data formats. Data accessibility aids communication, and when combined with early engagement across multi-disciplinary teams, the path to decision making is reduced, synergies gained, and costs are reduced through improved efficiency and optimization.

The Esso Long Island Point facility is situated on the edge of Western Port, an important Ramsar designated wetland for migratory birds in Victoria, Australia. The gas fractionation and crude oil storage facility has operated for over 40 years and has discharged treated wastewater to Western Port for most of these years in accordance with its environmental regulatory licence. The 2003 State Environment Protection Policy for Waters of Western Port is the Victorian Environment Protection Authority’s regulatory framework for licensing wastewater discharges to the wetland, and among other items, requires that discharges must cause no ‘detrimental change in the environmental quality of the receiving waters’ or ‘chronic impacts outside any declared mixing zone’. A major upgrade to the water treatment facility in 2010 included a risk-based marine ecosystem program to monitor key environmental indicators including water quality, jetty pile invertebrate communities and seagrass condition. The program’s longer-term monitoring record has allowed assessment of potential chronic effects on invertebrates and seagrass by comparing temporal changes at monitoring sites over the period from pre-operations (2010) to present (2016) and spatial changes between near-field to far-field sites, kilometres from the discharge point. The program has shown that management of the discharge maintains beneficial uses and environmental objectives at the boundary of the mixing zone, and the marine ecosystem is protected from potentially slower and longer-term adverse effects in the far-field. The program demonstrates that the treated wastewater discharge has had no adverse impact on key environmental indicators in Western Port over the longer-term study period.