The first edition of the guide was published when IPC came into force in England and Wales in April 1991. The revised version has been simplified and restructured and is more accessible as a result.
Only three noteworthy changes appear to have been made in the new edition. One of these concerns the meaning of "best available techniques not entailing excessive cost" (BATNEEC) as regards new processes.
The first edition said that there would be a presumption that BAT would be employed for new processes, but added that this presumption "can properly be modified by economic considerations where the costs of applying best available techniques would be excessive in relation to the nature of the industry and the environmental protection to be achieved."
The revised edition is more expansive. It says that "in many cases, for new processes it is expected that BAT and BATNEEC will be synonymous. However, the following principles should apply:
The two definitions come to much the same thing, except in that they underline the possibility of HMIP refusing an application and that, as far as new processes are concerned, it is the economic condition of a sector rather than a specific company which will determine decisions as to what constitutes BATNEEC. These are not novel features of IPC, but they have been given added emphasis in the new guide.
On existing processes, the first edition said that HMIP will be "concerned with establishing timescales over which old processes will be upgraded to new standards (or decommissioned)." In the revised version, that ambition has been somewhat attenuated. HMIP's concern now will be to establish timescales "over which old processes will be upgraded to new standards, or as near to new standards as possible, or ultimately closed down."
The third change concerns the circumstances in which an operator's application for information to be withheld from the public register on grounds of commercial confidentiality may be acceptable. The first edition said that the test would be whether disclosure of the information concerned "would negate or significantly diminish a commercial advantage." However, in the revised guide this has been reworded and extended, so that the test now is whether disclosure "would negate or diminish a commercial advantage, or produce or increase a commercial disadvantage which is unreasonable given the nature of the information and the financial effect of disclosure."