Posted on June 21, 2022 by Sue Puckeridge and

‘Substantially the same’ – identifying the fundamental elements of development

Other than to correct a minor error, misdescription or miscalculation, a development consent can only be modified under sections 4.55 and 4.56 of the Environmental Planning and Assessment Act 1979 (EPA Act) if the consent authority or the Court is satisfied that the development to which the consent as modified relates is substantially the same development as the development for which the consent was originally granted.

While this issue has been given detailed consideration by the Courts, a recent Land and Environment Court of New South Wales (Court) decision provides useful guidance for both applicants and consent authorities in applying this statutory test. Adopting the Court’s analysis, where a development contains more than one element, identification of the fundamental elements of an original development proposal is required. A determination must then be made as to whether the modification seeks to alter those fundamental elements to such a material degree that the modified development as proposed is no longer substantially the same development.


On 10 November 1994, the Court granted development consent for the construction and operation of a 120 megawatt power plant and construction of an ancillary slurry pipeline over adjacent land at Warkworth, NSW (1994 Consent), known as the Redbank Power Station. Prior to construction commencing, the consent was modified by the Court to, among other things, limit the fuel source for the power plant to coal tailings from the adjacent Warkworth Mine (1997 Modification). Following an increase in the market price of coal tailings, the power plant became uncommercial and ceased operating in October 2014.

On 3 November 2020, a modification application was lodged with Singleton Council (Council), seeking consent to amend the 1994 Consent, as modified by the 1997 Modification, to accommodate the use of biomass as a supplementary source of fuel for the power plant (Modification Application).

On 7 May 2021, the applicant on the Modification Application commenced class 1 proceedings in the Court against Council’s deemed refusal of the Modification Application.

Substantially the same development

In dismissing the Appeal, Justice Duggan found that, having regard to the totality of the 1994 Consent, she was not satisfied that the development to which the Modification Application related was substantially the same development as the development for which the consent was originally granted.

While accepting that the provisions of s 4.56 of the EPA Act are ‘beneficial and facultative,‘ Justice Duggan noted that this does not mean that the power to modify exists without constraint. Instead, the legislative power to modify remains subject to each of the specific gateways specified in the Act. In this case, the relevant gateway was that the development must remain substantially the same once amended as that which was originally approved.

Referring to the decision of Preston CJ in Arrage v Inner West Council [2019] NSWLEC 85 at [18], Her Honour affirmed that the relevant test under s 4.56 is that set by the statutory language, while also approving of judicial interpretations of “substantially the same” to mean “essentially or materially having the same essence”: Vacik Pty Ltd v Penrith City Council [1992] NSWLEC 8 at 4; Sydney Council v Michael Standley & Associates Pty Ltd (1998) 43 NSWLR 468 at 475 and 481-482.

Her Honour accepted the Council’s submission that it is generally permissible to have regard to an environmental impact statement (EIS) for the purposes of identifying the scope and nature of a proposed development, citing the decision of Preston CJ in Hunter Industrial Rental Equipment Pty Ltd v Dungog Shire Council (2019) 101 NSWLR 1 at [57], [64], [80] and [311].

Relevantly, the Executive Summary of the EIS which was expressly incorporated into the 1994 Consent, stated that the development would ‘provide an alternative means of permanent tailing disposal.’ Accordingly Council submitted that the development was ‘an integrated set of activities directed both at disposing of coal washery tailings and generating electricity, rather than as a power station per se.’

By reference to the EIS and other documentary material expressly incorporated into the 1994 Consent, Her Honour found that the development had two co-dependent interrelated purposes, being: the disposal of coal tailings; and the consequential generation of electricity from the process of the disposal of the coal tailings. Her Honour found that identifying the 1994 Consent in terms that limited it to, or prioritises it to, merely the generation of power ‘fails to properly identify the material and essential elements of the 1994 [Consent].’

Her Honour accepted the applicant’s submission that it is impermissible to “focus” upon a single element of the development when applying the test, however she found that:

this exercise cannot be undertaken in a numeric “tick a box” approach. The significance of a particular feature or set of features may alone or in combination be so significant that the alteration is such that an essential or material component of the development is so altered that it can no longer be said to be substantially the same development – this determination will be a matter of fact and degree depending upon the facts and circumstances in each particular case. Such an exercise is not focussing on a single element, rather it is identifying from the whole an element which alone has such importance it is capable of altering the development to such a degree that it falls outside the jurisdictional limit in s 4.56.’

Applying this test to the current facts, it was concluded that the Modification Application would alter the development in ‘such a fundamental manner’ that it would lose the essential and material relationship to the disposal of coal tailings from the associated mine operations, and accordingly it could not be characterised as being substantially the same development as the 1994 Consent.

The case can be read in full here: Hunter Development Brokerage Pty Limited trading as HDB Town Planning and Design v Singleton Council [2022] NSWLEC 64

If you would like to discuss the issues raised in this post, please contact Sue Puckeridge on 8235 9702 or Alex Rutherford on 8235 9720.