The focus of this paper is the framework of issue analysis developed and used by the NAO to test value for money in Private Finance Initiative /Public Private Partnership (PFI/PPP) projects. The framework takes the form of a hierarchy of statements expressed in terms of advice to the procurer. Starting from the general, these statements become increasingly detailed and specific. The paper highlights the ‘four pillars’ of issue analysis. It then presents brief case studies, which illustrate each of the four pillars, based on specific deals in which the NAO has applied this methodology, before drawing some conclusions about auditing PFI projects. The NAO's rigorous framework has already helped public bodies to secure more favourable PFI deals and should help to improve the value for money of future PFI deals.

A key challenge of the environmental regulatory framework for offshore petroleum activities in Australia is the requirement to demonstrate acceptability, with the legislation placing the onus on petroleum titleholders to demonstrate that the impacts and risks posed by an activity will be of an acceptable level and reduced to as low as reasonably practicable. This paper presents a case study on the assessment of noise impacts to fishes for the Bethany 3D Marine Seismic Survey, which was acquired by Santos Ltd in mid-2018. The survey area was encompassed entirely by the Oceanic Shoals Marine Park, and also overlapped a significant proportion of the Timor Reef Fishery, a regionally important demersal scalefish fishery. The survey area overlapped a key ecological feature and a range of geomorphic features characterised by benthic habitats supporting demersal and benthic fish communities, including site-attached species. On this basis, the evaluation of impacts and risks required a multi-faceted approach, with seven key elements: (1) acoustic modelling; (2) application of sound exposure guidelines; (3) a quantitative risk assessment (benthic habitat predictive modelling and spatial analysis of site-attached fish assemblages); (4) the definition of an acceptable level of impact; (5) a sound source verification process; (6) engagement with key stakeholders; and (7) an independent, expert peer review process. The outcomes of each of these steps were incorporated into the environment plan, and enabled the titleholder to demonstrate that, with adopted control measures in place, environmental impacts and risks from the seismic survey could be managed to an acceptable level.

A common approach to environmental risk assessment when assessing the level of risk to marine animals during marine seismic surveys is to compare either measured or modelled estimates of underwater sound levels to a known sound level threshold criteria. Over the years, a number of measures have been used to calculate and characterise underwater sound thresholds, including: sound pressure level (SPL), a root mean square (RMS) calculation, and—more recently—sound exposure level (SEL). SEL was suggested in 2007 by an expert panel of researchers as an appropriate measure to reduce the risk of temporary threshold shift (TTS) occurring in marine animals. Petroleum Geo-Services (PGS) commissioned an SEL study in preparation for a large MultiClient 3D seismic survey planned for the environmentally sensitive Camden Sound area, Western Australia, in late 2010. The Centre for Marine Science and Technology (CMST) at Curtin University built a comprehensive bathymetric model of the Camden Sound area and used two seabed geoacoustic models, with sand/limestone—as worst case, most reflective—and silt—as best case, least reflective. Acoustic propagation modelling over the frequency range of 8–1 kHz was used to build 3D maps of sound levels throughout all areas relevant to the seismic survey. The CMST SEL modelling results were integrated with other airgun array and SEL modelling pursued by PGS, and represent part of a broader environmental management strategy by PGS. Discussion is also given to other variants of SEL modelling.