Whether the list of prescribed persons under S42(a) needs to be the same as the list of 'prescribed consultees' for EIA purposes (issued under Reg 9) and which public gas transporters and relevant statutory undertakers to consult.

The bodies the IPC write to and list under EIA Reg 9 is the same as the IPC would consult in preparing a Scoping Opinion.
As per regulation 3 of the Infrastructure Planning: Applications Prescribed Forms and Procedures Regulations 2009 (APFP Regulations ): The list of prescribed consultees for S.42(a) is set out in in column 1 of the table in schedule 1 APFP Regulations.Column 2 of that table defines the circumstances when particular categories of consultees need to be consulted.
Regulation 9(1) of the Infrastructure Planning (Environmental Impact Assessment) Regulations 2009 (EIA Regulations) requires the IPC to notify 'the consultation bodies' when it receives a notification from an applicant under EIA Regulations 6(1)(b) or 6(2)(b). Reg 2 (1) of the EIA Regulations defines 'the consultation bodies' as
"(a) a body prescribed under section 42(a) (duty to consult) and listed in column 1 of the table set out at Schedule 1 to the Infrastructure Planning (Applications: Prescribed Forms and Procedure) Regulations 2009 (a) where the circumstances set out in column 2 are satisfied in respect of that body;
(b) each authority that is within section 43 (local authorities for purposes of section 42(b));and (...)"
In other words the table in schedule 1 APFP Regulations is the starting point for determining the consultation bodies for both the IPC's Reg 9 list and the applicant's consultation under S.42 (a). However, as IPC advice note 3 (attachment 1 goes on to explain "in some cases, the Commission must exercise discretion in deciding which bodies should be consulted by adopting a "relevance test" and/or by deciding whether certain circumstances apply (the "circumstances test")". Advice Note 3 then goes on to explain in detail how the IPC applies the relevance and circumstances test and identifies statutory undertakers etc. In addition, the advice note sets out "a limited category of bodies, not prescribed by the APFP, who will be consulted by the Commission before adopting a scoping opinion". (This equally applies to Reg 9 lists).
The IPC has therefore issued guidance specifically about the point on whether or not the applicant's list of S42 consultees needs to be identical to the IPC's list of consultees in the IPC Guidance Note 1 (attachment 2
"Paragraph 21: When meeting their statutory pre-application obligations under s42 of the Act applicants must make diligent inquiry, carry out their own investigations and take legal advice as appropriate. Applicants may nonetheless find it helpful to recognise and understand the approach taken by the IPC when meeting the IPC?s own obligations under the EIA Regulations (see the relevant advice note). The IPC has undertaken a careful review of the consultation bodies prescribed under s42(a) of the Act and considers that its approach to identifying those consultation bodies is reasonable and proportionate.
Before accepting an application for examination the IPC must conclude that the applicant has complied with Chapter 2 of Part 5 of the Act (pre- application procedure). If applicants identify and consult fewer consultation bodies (as part of their s42 obligations) than the IPC consults in relation to a scoping opinion request a clear explanation should be provided when the application is submitted. This will assist the IPC to reach a conclusion about whether or not to accept the application(12).
Paragraph 22: The consultation report will enable applicants to flag and explain any differences between the IPC?s consultation under the EIA Regulations(13) and their own s42 consultation. Differences may arise as a result of additional information becoming available to promoters as part of their due diligence exercise which was not available to the IPC when identifying consultation bodies or because promoters have, on the basis of additional information, properly exercised judgment and reached a different decision. This should be made clear in the consultation report."
(12) In accordance with s55(3)(e) of the Act
(13) IPC scoping opinions include a list of consultation bodies consulted before adopting the scoping opinion. The IPC is also required to inform the applicant, under regulation 9(1)(b) of the consultation bodies notified.
Concerning your query regarding public gas transporters and relevant statutory undertakers:
As per our Advice Note 3 'Scoping Opinion Consultation' (attachment 3 - p.4) 'statutory undertaker' has in the APFP Regs the same meaning as S127 of the Planning Act 2008 and the meaning given by S8 of the Acquisition of Land Act 1981. Public gas transporters are deemed statutory undertakers for the purposes of the Acquisition of Land Act (p.6 of IPC Advice Note 3) due to the Gas Act 1995 Schedule 4 para 2 (1).
Schedule 1 of the APFP Regs defines relevant as: "'relevant' in relation to a body, shall mean the body which has responsibility for the location where the proposals may or will be sited or the body which has responsibility for an area which neighbours that location".
P.6 of the IPC's Advice Note 3 further explains how the Commission applies this to the identification of relevant public gas transporters in compiling the list of consultation bodies which it must consult before adopting a Scoping Opinion:
"The licence conditions of public gas transporters do not, in every case, limit operations to a specific geographical area. Taking a cautious approach, the Commission will consult all public gas transporters whose licence covers Great Britain. This is done on the basis that it is not possible to identify which transporter "has responsibility for the location where the proposals may or will be sited" or "has responsibility for an area which neighbours that location".
In other words, the Commission includes public gas transporters on its list of consultation bodies to consult before adopting a Scoping Opinion for all types of NSIPs.