New York Attorney General Eric Schneiderman is investigating ExxonMobil over its reporting of its asset valuations, widening the probe launched last year into the oiler's disclosures on climate change.

Schneiderman is looking into why ExxonMobil has not followed its peers in the oil and gas industry in taking large non-cash charges for write-downs in the value of its assets, an individual briefed on the investigation told London's Financial Times.

In light of that, and the US Securities and Exchange Commission probe of ExxonMobil's assessment of future climate impacts on evaluating projects, Australian Protemics Analysis Facility founder Keith Williams said similar questions should be raised about a costly deepwater drilling plan in Australia's southern margin when countries around the world are factoring in reduced fossil fuel use to meet COP21 climate goals.

"It seems to me that there has been no explicit analysis of the cost-benefit of this project in the context of a carbon-constrained world. And other than saying that there isn't a problem, there seems not to have been any attempt to justify endangering a marine park," Williams wrote in a piece published on Seeking Alpha.

Valuation

Williams, who started his career as a research scientist in developmental biology, biochemistry, molecular biology in Australia, Oxford in the UK and in Germany, said it was no longer credible to say that emissions reductions were "anything other than an urgent issue of great relevance to valuation of assets and reviewing new capex in terms of stranded assets".

Of particular concern to Williams is BP's admission that its Bight jaunt is technically similar to the Deepwater Horizon project.

Williams cited 2013 quotes from BP's Perth-based vice president for wells and new ventures Mark Stanley who said that from an acreage position, the next piece of land to the south is Antarctica, which is some 4000km away.

"Waves have a tremendously long distance to build in height and extend in length. A wave height of 10m would not be unheard of - that's comparable to the North Sea - but we will be seeing them more regularly," Stanley said.

"Such a hostile environment will require highly-specialised rig facilities to drill the four exploration wells agreed under the permit.

"We've had great support from colleagues in Houston who have shared lessons from the Deepwater Horizon accident. They have flown out here and spent time with representatives from the federal and state governments, so we can demonstrate that we know what is required to operate in the GAB."

Response plan

In its Environment Plan Overview for EPPs 37 and 39 published last month, BP addressed concerns over water depths, economic opportunities, public access to the environmental plan, impact of underwater sound on marine life, dispersant use, well blow-out prevention and response, and public access to oil spill modelling and oil spill response documents.

BP acknowledged that "a number of stakeholders" had raised concerns regarding the oiler's capacity to prevent drilling difficulties, with a focus on spills resulting from a loss of well control, particularly in light of the Deepwater Horizon incident.

Specific questions focused on the use of capping stacks and BP's capacity to quickly drill a relief well.

BP followed this up with face-to-face meetings with its GAB engineering team leader and GAB crisis and continuity and emergency response

BP gave specifics on capping and containment, loss of well control prevention and response measures, along with oil spill planning and response.

Inadequate

The Wilderness Society said yesterday that BP's oil spill response plan strategy for a spill in the Bight was "woefully inadequate".

"BP's own documents admit that physically containing an oil spill using booms and skimmers would not be effective in the Bight's rough waters, will rely heavily on the use of toxic oil dispersants, cites a ‘Vessels of Opportunity program' that does not appear to exist in Australia, suggests it can move Bight wildlife, which whales and great white sharks, away from an oil spill," Wilderness Society national director Lyndon Schneiders said.

"BP says neither it nor the South Australian and Western Australian governments have completed plans to deal with oiled wildlife, yet it claims that 122 personnel can clean oiled wildlife on 1200km of coast and, failing that, can train volunteers ‘just in time'.

"BP outlines responses but does not say how or whether those responses can be implemented. It does not outline how many resources such as boats, aircraft and trained personnel are needed and where would they come from."

Wilderness Society SA director Peter Owen noted that the SA Oyster Growers Association says SA and neighbouring states did not have the number of vessels used in the Gulf clean-up and probably only 20 could operate safely in the waters where BP plans to drill.

"Members would likely be using their boats to attempt to save their oyster stocks. In Port Lincoln BP would be relying on the fishing industry, which BP admits may be more concerned with rescuing tuna pens," Owen said.

Citing the fact that BP's oil spill response plan strategy overview comprised just 15 pages compared to the 438-page document Shell gave the public for its plans to drill in the Arctic, Owen called on the offshore regulator to "finally end this farce and finally reject BP's application to drill in the Bight".

A decision on BP's plans for its first two wells are expected by mid-week.