I stumbled on this this just now and haven't read much of it yet . Looks interesting at a glance .My head is spinning. I have not been convinced that rail freight has a significant impact on total pollution in either urban or regional environments, in Australia. To me this appears to be a bureaucracy in search of a problem. As a base line I think it is appropriate that there is some comparison between the emissions produced by(for example) one 4500 tonne coal train travelling between Airly and Inner Harbour and the road transport equivalent. I'd be surprised if 4X82s or 3x93s emit more emissions than 60 B-doubles. Does a thirty year old two-stroke on rail produce bad stuff? Absolutely. Is the road transport alternative cleaner? It doesn't seem to have been considered.
Had a quick sift through and yep the data looks interesting . It remains to be seen how aggressive our EPA wants to be with the changes that look like coming .You may have seen the documentation for the tier 0+ upgrade kits fitted to 8113 and a 90 class. From memory, the upgrade didn't really meet the manufacturers claims and there was a significant increase in consumption. I can see huge expense for operators, that will likely result in more road transport and more pollution, not less. You and others, have recently mentioned alignment improvements, on other threads. I can't imagine the EPA would be interested as these would be a cost to government rather than cost to private enterprise.
If they insist on Tier 4 emissions with new locomotives then the choices from the US would appear to be the latest spec GE and EMD engines . That would involve some interesting alterations to our latest National standard gauge style units if they are to use the Gevo and EMD 1010J type power assemblies .
Also rebuilds get a mention and at least there is somewhere to go with say older spec 710s , should be upgradable to the later Tier 3 spec like later Two Stroke 70ACEs have .PN lucked out with their NR re power grogram that came with later computers and injection for the ageing FDL engine design . Their 93s were an update on the original 92 and I think some of the differences may have been inverter and computer related .
I can see this being the death warrant for Alco powered units in the long term if the EPA pushes it .
Not sure where you'd go with the EMD 645 powered units needing a rebuild , don't know if the local operators are interested in 710 Eco type upgrades .
No I didn't know about the 81 or 90 class Tier 0 experiment . I was originally searching for fuel consumption differences between tier 2/3 and Tier 4 in the US . 81s were never exactly economical from new and 90s I wouldn't know because I never worked on them .http://www.epa.nsw.gov.au/resources/air/diesel-locomotive-emissions-report.pdf
I don't remember reading that Tier 1/2/3 caused the American operators that much grief fuel consumption wise but I did read that the tier 4 newbys had something like a 5 to 10 percent fuel penalty over Tier 3 units .