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At Barangaroo South on Sydney's central business district waterfront, Australia, Lend Lease is working with the New South Wales government on the A$6 billion (£4 billion) transformation of a former container port into a thriving business, residential and leisure precinct. The vision is that Barangaroo South will enhance Sydney's position as an internationally appealing, globally competitive, environmentally sustainable city. The development will be Australia's first large-scale carbon dioxide neutral precinct. Barangaroo South will feature three commercial towers ranging in height from 39 to 49 storeys, sharing a common, two-level basement to be retained around its perimeter by an approximately 770 m long diaphragm wall, socketed into Sydney sandstone. As the basement excavation will be below sea level, it is essential that the site retention wall for the basement also acts as a cut-off against groundwater ingress. This paper provides an overview of the design and construction challenges facing the installation of the diaphragm wall and the innovative solutions adopted to overcome these challenges. [ABSTRACT FROM AUTHOR]

Abstract: The efficacy of technologies to reduce enteric CH4 emissions from ruminants are typically evaluated on individual animals with little consideration of enterprise scale impacts. While impacts of the many rumen manipulations being studied are hard to anticipate, there is adequate information to assess impacts of farm management changes and potential animal genetic changes on whole farm productivity and enteric CH4 emissions. Seven common sheep production systems grazing an annual pasture in central New South Wales, Australia, were modelled using GrassGro® (version 3.1.2). A range of animal management and animal genetic strategies were examined for their impact on total enteric emissions, emission intensity (i.e., kg CO2 equivalent/kg live weight (LW) of animal sold) and profit. Within enterprises, mitigation options were compared at their respective sustainable economic optimum stocking rate as it was assumed that farmers would seek to achieve the highest sustainable profit achievable from a finite land resource. Management options considered were choice of lambing time, mating ewes for the first time as lambs rather than yearlings, and feeding lambs to reduce time to slaughter. The potential for using selective animal breeding was also tested, with sheep physiological parameters being altered in GrassGro® to represent genetic improvement in fecundity, LW gain, residual feed intake and CH4 yield. In general, the management choices delivering lowest emission intensity were also the most profitable within sustainability constraints. Mating maiden ewes as lambs was only effective in reducing enterprise emissions intensity in self-replacing flocks (i.e., no purchased replacements). When stocking rates were at the sustainable economic optimum, choice of enterprise or management had little influence on total enteric emissions from the enterprise. If decisions are guided solely by economics, farmers are likely to continue with similar levels of production (and emissions) until a price on enteric CH4 emissions makes the sheep enterprise unprofitable, or an alternative more profitable enterprise than sheep grazing emerges. Improving animal genetics for residual feed intake or CH4 yield offers opportunity to reduce enterprise emissions, but industry progress toward higher genetic merit for these traits is expected to be slow due to relatively low heritability and competing economic imperatives for progress in other traits. This paper is part of the special issue entitled: Greenhouse Gases in Animal Agriculture – Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors: K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson. [Copyright &y& Elsevier]

This paper evaluates the teaching and learning outcomes from a first-year project-based engineering course at the University of New South Wales. The students worked in teams to design and build a device to sequester "CO2" into a reservoir. We present our observation of the peer assessments, performance prediction and diversity of the students. We found that some teams collaborated more effectively than others. We quantified this effectiveness using an online peer assessment that enables students to rate the performance of their teammates. These ratings were incorporated into the assignment of individual marks for group assignments. The analysis of the marks students achieved for various assessments and components of the course is presented. We observed that female students tended to out-perform their peers in both individual and team assessments, and students who did well in individual components of the course also did well in the team components. The use of early assessments to predict performance in later assessments seems to be difficult. However, there is a strong connection between students' results for their design proposal and their results for the final design work. We are able to show statistically a signifi cant improvement for marks for presentations but not for report writing. Anonymous surveys showed that about 90% of students were satisfied with their experience of the course. Students found this course to be challenging and enjoyable, giving them a good start in developing their skills as engineers. [ABSTRACT FROM AUTHOR]