Chief Executive Officer of Customs v Adelaide Brighton Cement Ltd

· the limestone is 'agricultural use limestone'; or

· a mineral or minerals is subsequently separated from the limestone so as to be recovered in a form other than limestone.

8 The central point of law that arises in this appeal is, therefore, the determination of the correct interpretation of the exception to the definition of 'minerals' within the broader definition of 'mining operations'. Once the correct interpretation of that provision is established it will be necessary to consider whether the Tribunal applied the correct construction of s 164(7) of the Act to the facts as found. 9 Both parties referred to two recent decisions of the Full Court: Goliath Portland Cement Limited v Chief Executive Officer of Customs (2000) 101 FCR 11 ('Goliath') and David Mitchell Limited v Chief Executive Officer of Customs (2001) 107 FCR 252 ('David Mitchell'). Customs relied on Goliath and submitted that David Mitchell should be distinguished or not followed. Adelaide Brighton submitted that both cases were consistent and supported the Company's position.

INTERPRETING THE ACT 10 Where, as here, a few narrowly focused amendments have been made to parts of a broader legislative scheme, the question that immediately suggests itself is (to use a traditional expression): Was there some 'mischief' that the Parliament perceived and that it intended the amendments to remedy? 11 As McHugh ACJ, Gummow and Hayne JJ recently restated in Network Ten Pty Limited v TCN Channel Nine Pty Limited (2004) 205 ALR 1, in a discussion of the principles of statutory interpretation (at 4 [11]): '[A] court is permitted to have regard to the words used by the legislature in their legal and historical context and, in appropriate cases, to give them meaning that will give effect to any purpose of the legislation that can be deduced from that context.' (citing McHugh J in Newcastle City Council v GIO General Ltd (1997) 191 CLR 85 at 112.) and: 'It is well settled that at common law, apart from any reliance upon s 15AB of the Acts Interpretation Act 1901 (Cth), the court may have regard to reports of law reform bodies to ascertain the mischief which a statute is intended to cure. Moreover, the modern approach to statutory interpretation (a) insists that the context be considered in the first instance, not merely at some later stage when ambiguity may be thought to arise, and (b) uses "context" in its widest sense to include such things as the existing state of the law and the mischief which, by legitimate means such as those just mentioned, one may discern the statute was intended to remedy. Instances of general words in a statute being so constrained by their context are numerous. In particular, as McHugh JA pointed out in Isherwood v Butler Pollnow Pty Ltd, if the apparently plain words of a provision are read in the light of the mischief which the statute was designed to overcome and of the objects of the legislation, they may wear a very different appearance. Further, inconvenience or improbability of result may assist the court in preferring to the literal meaning an alternative construction which, by the steps identified above, is reasonably open and more closely conforms to the legislative intent.' (citing Brennan CJ, Dawson, Toohey and Gummow JJ in CIC Insurance Ltd v Bankstown Football Club Ltd (1997) 187 CLR 384 at 408 (footnotes omitted).) 12 This approach to legislative interpretation also has legislative backing in s 15AA of the Acts Interpretation Act 1901 (Cth) which establishes: 'In the interpretation of a provision of an Act, a construction that would promote the purpose or object underlying the Act (whether that purpose or object is expressly stated in the Act or not) shall be preferred to a construction that would not promote that purpose or object.' 13 As Dawson J held in Mills v Meeking (1990) 169 CLR 214 at 235, discussing the equivalent Victorian provision: 'The requirement that a court look to the purpose or object of the Act is thus more than an instruction to adopt the traditional mischief or purpose rule in preference to the literal rule of construction. The mischief or purpose rule required an ambiguity or inconsistency before a court could have regard to purpose: Miller v Commonwealth (1904) 1 CLR 668 at 674; Wacal Developments Pty Ltd v Realty Developments Pty Ltd (1978) 140 CLR 503 at 513. The approach required by s 35 needs no ambiguity or inconsistency; it allows a court to consider the purposes of an Act in determining whether there is more than one possible construction.' 14 Before turning to the legal and historical context in which the exception to the definition of 'minerals' was introduced, it is as well to bear in mind that s 15AB of the Acts Interpretation Act 1901 (Cth) allows a court to have regard to a broad range of material to assist in the process of interpretation. Section 15AB relevantly provides: '(1) Subject to subsection (3), in the interpretation of a provision of an Act, if any material not forming part of the Act is capable of assisting in the ascertainment of the meaning of the provision, consideration may be given to that material: (a) to confirm that the meaning of the provision is the ordinary meaning conveyed by the text of the provision taking into account its context in the Act and the purpose or object underlying the Act; or (b) to determine the meaning of the provision when: (i) the provision is ambiguous or obscure; or (ii) the ordinary meaning conveyed by the text of the provision taking into account its context in the Act and the purpose or object underlying the Act leads to a result that is manifestly absurd or is unreasonable. (2) Without limiting the generality of subsection (1), the material that may be considered in accordance with that subsection in the interpretation of a provision of an Act includes: … (c) any relevant report of a committee of the Parliament or of either House of the Parliament that was made to the Parliament or that House of the Parliament before the time when the provision was enacted; … (e) any explanatory memorandum relating to the Bill containing the provision, or any other relevant document, that was laid before, or furnished to the members of, either House of the Parliament by a Minister before the time when the provision was enacted; (f) the speech made to a House of the Parliament by a Minister on the occasion of the moving by that Minister of a motion that the Bill containing the provision be read a second time in that House;…'

the legal and historical context of s 164(7) of the customs act 15 As the reasons for judgment of the majority show (at [83] - [86]) between 1995 and 1997 several amendments were made to the provisions of the Act relating to the diesel fuel rebate scheme. In the second reading speech introducing the Bill that later became the Customs and Excise Legislation Act 1995 (Cth) ('CELA Act 1995'), and which made the first set of amendments, the Parliamentary Secretary to the Minister for Industry, Science and Technology said: 'The Customs and Excise Legislation Amendment Bill 1995 contains a range of measures announced in the budget to amend the provisions of the Customs Act 1901 and the Excise Act 1901 relating to the diesel fuel rebate scheme. The amendments are principally designed to tighten the eligibility criteria for rebates of customs or excise duty which have been paid on purchases of diesel fuel, so that the integrity of the scheme as it was introduced in 1982 to assist those engaged in mainstream primary production and those engaged in mainstream mining operations can be maintained.'

(Hansard, House of Representatives, 7 June 1995 at 1476)

16 In the second reading speech introducing the Bill that later became the Customs and Excise Legislation Amendment Act (No 1) 1997 ('the CELA Act 1997'), the last amending Act in the series, the Minister for Small Business and Consumer Affairs explained: 'The government's clear intention is that rebate paid under the legislation should be confined to the narrow definition of eligible activities in the legislation - that is, the intention is not that the legislation be defined broadly and beneficially.'

(Hansard, House of Representatives, 12 December 1996 at 8430) 17 Although the Minister's speech was made after the amendment to the definition of 'minerals', his observations may be given some weight in the context of a related series of amendments to the Act with an apparently common goal. They also invite attention to the principle of statutory interpretation that although beneficial legislation (which customs rebate provisions are accepted to be: see Re Santos Resources Pty Ltd and Collector of Customs (Qld) (1988) 18 ALD 11 at 24and the authorities cited) is generally to be construed broadly in favour of its beneficiaries, excepting provisions within beneficial legislation need not for that reason be given a liberal interpretation (see Rose v Department of Social Security (1990) 21 FCR 241 at 244). As Pearce and Geddes observe in Statutory Interpretation in Australia (5th ed. 2001) at [9.5]: 'Exceptions may be included in the legislation to provide the practical balance between competing public interests. As such they should be interpreted carefully in order not to destroy that balance.' 18 Within this broader context, I now turn to consider whether there can be discerned a specific mischief that the CELA Act 1995 amendment to the definition of 'minerals' in s 164(7) of the Act, as modified by the Customs and Excise Legislation Amendment Act 1996 (Cth) ('CELA Act 1996'), was intended to remedy.

The mischief the Parliament intended to remedy - Extrinsic materials 19 In the second reading speech for the Bill for the CELA Act 1995, the Parliamentary Secretary explained the amendment to the definition of 'minerals' as follows: '[it involves:] the narrowing of the definition of "minerals" in the Customs Act 1901 so as to exclude from rebate eligibility diesel fuel used in mining for minerals, where those operations simply involve the extraction of sand, sandstone, soil, clay, granite, water and the like, from 1 August 1986…'

(Hansard, House of Representatives, 7 June 1995 at 1476)

20 He went on to explain what was meant by 'operations that simply involve the extraction of sand, sandstone, soil, clay granite, water and the like': 'Until recently, the Administrative Appeals Tribunal and the Federal Court have held the view that the term 'mining for minerals' in the act's definition of "mining operations" introduced a purposive test requiring a rebate claimant to demonstrate that the purpose of the claimant's operations was to obtain a mineral or minerals embedded in the material that was extracted. For instance, there was a clear distinction between the extraction of sand per se and the extraction of sand with a view to obtaining from it minerals such as rutile, zircon or almandite. The meaning of "mining operations" was therefore considered to be reasonably well settled until a recent decision of the Administrative Appeals Tribunal on the issue of extracting sand for use in the making of concrete or for use as bedding sand in the construction industry. The tribunal decided that the extraction of such sand was eligible for rebate. Claims have also been received for rebate on diesel fuel used in the pumping of ground water to be supplied as drinking water to towns. These are, in the government's view, uses well beyond the intent of the scheme, which was and is to deliver an assistance measure to mainstream mining pursuits. Accordingly, in item 7 of schedule 1 to the bill, the government has proposed to amend the definition of "minerals" to exclude sand, sandstone, soil, slate, clay (other than betonite or kaolin), basalt, granite, gravel, limestone and water. The exclusion is consistent with the principal mining legislation of the States and would bring about a transparent distinction between mining for minerals and operations that cannot, in the ordinary sense, be regarded as mining. Where these materials are extracted for the purpose of recovering a mineral, the extraction will remain eligible for rebate.' (Emphasis added).

(Hansard, House of Representatives, 7 June 1995 at 1477-1478)

21 The explanatory memorandum also identified the purpose of the amendment to the definition of 'minerals' as (at 11): 'to exclude from eligibility for the payment of rebate diesel fuel for use in extracting certain materials from the ground because they are valuable as extracted, rather than for the purpose of recovering their inherent mineral qualities. For example the use of diesel fuel in the mining of sand for its use in concreting, rather than for the purpose of extracting the minerals contained in the sand, is to be excluded from eligibility for rebate (Emphasis added.) 22 Further consideration was given to the Bill by the Senate Economic Legislation Committee. Public hearings were held and a report was tabled in the Senate on 26 June 1995, prior to the enactment of the CELA Act 1995 (Australian Senate, Economics Legislation Committee, Report of the Consideration of the Customs and Excise Legislation Amendment Bill 1995). Section 15AB(2)(c) of the Acts Interpretation Act 1901 (Cth) specifically authorises consideration of such a report as an aid to interpretation (see s 15AB(2)(c) set out at [14] above and a report such as this, reflecting further parliamentary consideration of proposed legislation of a technical nature, is entitled to considerable weight when seeking to discover the purpose of the legislation to which the report relates. The Committee noted (at 3): 'The definition of "minerals" contained in the Bill does not include sand, sandstone, slate, clay, basalt, granite, gravel and limestone. In evidence to the Committee, Boral Limited, CSR Limited and Pioneer International Limited condemned this exclusion, stating that a "…succession of court cases has concluded that industrial minerals are included in the Diesel Fuel Rebate Scheme." Boral Limited, CSR Limited and Pioneer International Limited stated that the ineligibility of industrial minerals is discriminatory, and that there "…is no fundamental reason why some extractive industries should have access to the DFRS whilst others are excluded." Similar concerns were raised by the Cement Industry Federation, regarding proposed ineligibility for rebate of diesel fuel used in the mining of limestone extracted to produce minerals for the production of cement.' 23 Notwithstanding these concerns, the majority report of the Committee supported the Bill and recommended that it be agreed to. It noted the Government's view that (at 7): 'The DFRS differentiates between industrial minerals and other minerals, as industrial minerals are extracted for use as a whole, in their "own value", rather than as material from which other minerals will be extracted. 24 As I read the second reading speech and the explanatory memorandum, particularly when seen in the light of the further consideration given to the Bill by the Senate Committee, they seek to draw a distinction between operations that involve extracting one of the materials, listed in the exception to the definition of 'minerals', for use as that material, and operations that involve taking the extra step of extracting or obtaining other minerals from those materials. This suggests that in respect at least of the exception to the definition of 'minerals' in s 164(7) of the Act, separating a mineral from the excluded material extracted from the earth was intended to be an essential requirement to avoid the exception, even if not an essential element in the general concept of recovery in the definition of 'mining operations': see at [109]-[115] of the joint judgment of Tamberlin, Sackville and Finn JJ.

The mischief the Parliament intended to remedy - The Neumann Sands case 25 Although not identified by name, it is clear that the decision of the Tribunal referred to in the second reading speech of the Bill for the CELA Act 1995 (extracted at [20] above) was Neumann Sands Victoria Pty Ltd v Australian Customs Service (Q93/764) ('Neumann Sands'). Since the Tribunal's decision is cited as the event that prompted the amendment to the definition of minerals in the Act, an analysis of the decision ought to reveal the mischief that the CELA Act 1995 was intended to remedy. (An appeal from that decision to the Federal Court was heard and decided after the CELA Act 1995 had come into force. Applying the Act as it stood prior to the 1995 amendments, Cooper J upheld the Tribunal's decision: Collector of Customs v Neumann Sands (Victoria) Pty Ltd (1996) 136 ALR 584.) 26 In Neumann Sands, the company sought review of the refusal by the Australian Customs Service of its application for a diesel fuel rebate for the diesel fuel used in 'sand beneficiation at Clayton Road, Clayton South in the State of Victoria'. Its operation involved the production of sand for use as a fine aggregate in concrete production. To be suitable for concrete production the sand needed to be made up of 90% silica, to be free of lignite and other debris found at the site and to have a maximal surface area and particle density. A secondary or by-product of the operation was bedding sand, for use in the bedding of water pipes. 27 The raw material was extracted from the site using a dredge. It was then passed through a treatment plant, where it was screened and sorted for size and composition and impurities such as lignite were removed. After the treatment plant, the fine sand aggregate was stockpiled and tested daily to isolate the sand falling within the grading envelope specified by the relevant Australian Standard. The fine aggregate, which Neumann Sands ultimately produced, was composed of 90.2% silicon dioxide in the form of quartz and smaller amounts of rutile, zircon, magnetics and non-magnetics. 28 The question before the Tribunal was whether these activities could be characterised as 'mining operations', or in other words constituted 'mining for minerals' within the meaning of s 164(7) of the Act. Customs had conceded that if Neumann Sands' operations were 'mining for minerals' then the screening and sorting process was 'beneficiation of the minerals mined' and the diesel fuel used by the company in that process would be eligible for the rebate. The Tribunal found that (at [45], [47]): 'a dredging operation of the type operated at Clayton South may be described as mining… we find that the purpose of the operation was to win sand for a particular use i.e. for use as fine aggregate. In view of the procedure that Neumann Sands carried out to isolate particular material, to use some material for the purpose of bedding sand and to discard other material altogether, we find that Neumann Sands were not content to win just any sand. It had to be particular sand with particular qualities. The qualities related to things as its durability, density, chemical inertness and hardness as well as to its size. The qualities other than its size are related to its chemical composition… Without the qualities of its chemical content, there was no point for Neumann Sands purposes in its winning the sand. It chemical content was directly related to its comprising a high silica content, some 90.2%, and other inert and durable material. The dimensions of the grains of sand were also important, but although vital, size was not in itself determinative in Neumann Sands' decision to extract the sand. Both its size and intrinsic qualities were essential for Neumann Sand's purpose and one would not do without the other for use as fine aggregate for the manufacture of concrete. The sand was clearly won for industrial purposes. As its primary content was silica, which is an industrial mineral, and as it was won by methods which may be described as mining and Neumann Sands' purpose in winning the sand was primarily to win it for its quartz content, we find that its operations at Clayton South were mining for minerals within the meaning of sub-section 164(7) of the Customs Act.' 29 The Tribunal therefore set aside the decision refusing the diesel fuel rebate and substituted a decision that a rebate of duty was payable. 30 To my mind, the fact that the amendment to the definition of 'minerals' was prompted by this decision points almost irresistibly to the conclusion that the words 'except sand, sandstone, soil, slate, clay (other than bentonite or kaolin), basalt, granite, gravel, limestone or water' were intended to exclude operations such as those undertaken by Neumann Sands and similar operations for the recovery of limestone and the other materials listed in the exception. 31 The essential feature of the operation in Neumann Sands was that although the material was sought for its particular mineral content, the valuable minerals were not extracted from the dredged material. To use the language of the report of the Senate Committee, the material in the Neumann Sands case was extracted for use as a whole, in its 'own value', rather than as material from which other minerals were to be extracted. 32 Adelaide Brighton's activities, although relating to limestone rather than sand were relevantly very similar to those undertaken by Neumann Sands. Before beginning its mining operations, Neumann Sands carried out extensive tests to ensure that the sand at Clayton South could be processed to produce fine aggregate for concrete production that satisfied the Australian Standard. Although no specific mineral composition was specified by the Australian Standard, quartz was recognised as a mineral that had the requisite physical properties to meet that standard and therefore sand high in quartz content was more likely to be suitable for concrete production. Adelaide Brighton also tested the limestone deposit at Klein Point before beginning its mining operations, to ascertain its mineral composition and to determine whether the deposit was suitable for the production of cement. Its aim was to produce 'cement grade limestone' or limestone made up of 85% calcite, 10.5% silica, 1.5% alumina, 1.2% haematite and no more than 1.2% of magnesium and 0.36% of potassium and sodium. 33 As previously noted, the sand at Clayton South was dredged and run through a treatment plant, which screened and sorted the material for size and chemical composition and removed impurities. The resulting fine aggregate was then tested to ensure that it met the relevant Australian Standard. Similarly, to produce 'cement grade limestone', Adelaide Brighton first removed and disposed of the topsoil and the hardened top layer of limestone called 'kunkar' and then quarried and crushed the remaining limestone. The mineral composition of the limestone varied across the deposit and crushed limestone from different locations in the deposit was mixed together in a stockpile to obtain the required mineral composition. The stockpile was regularly tested to ensure the requisite composition of minerals was obtained. 34 The final product produced by Neumann Sands was found to be 90.59% mineral, the majority of which was quartz with the remainder comprising rutile, zircon and ilmenite. The composition of Adelaide Brighton's 'cement grade limestone' was 98.2% mineral, principally calcite, but also silica, alumina and haematite. 35 Thus in the operations of Adelaide Brighton, as in the operations of Neumann Sands, material was extracted for use as a whole, in its own value. In each case, the raw material was sought because its mineral content, and the associated physical characteristic of the minerals, made the material useful for its intended purpose. In each case, however, the material mined retained its physical character; in one case as limestone and in the other as sand. 36 It is worth noting that in Neumann Sands Customs had argued unsuccessfully that the purposive test applied to determine whether an activity constitute mining for minerals had been taken too far in Boral Bricks (Qld) Limited v Australian Customs Service (1988) 18 ALD 456, a Tribunal decision in which Deputy President Breen held (at 456): 'Whilst the definition imposes a purposive test, the legislation does not by its combined effect mean that rebate is payable only to persons or companies whose operations are designed to win material from which will be extracted raw materials. The rebate is also payable where the mining operations result in the winning of a product, the end use of which is dependent upon, inter alia, perhaps, its mineral content. That the operator does not in advance, by chemical testing or otherwise, place himself in a position of being able to give a specific and detailed identity to that content, does not mean that his operations are outside the scope of the legislation.' (see at [42]-[43] of the Tribunal's decision: Neumann Sands Victoria Pty Ltd v Australian Customs Service (Q93/764)). 37 This provides some basis for an inference that it was Parliament's intention in amending the Act after the failure of this argument before the Tribunal, to exclude from the definition of minerals all those materials as to which it was felt the purposive test was capable of overreach as a result of Tribunal decisions. 38 As the extrinsic materials point to the intention of the amending legislation being to reverse the result in Neumann Sands and to deny eligibility for the diesel fuel rebate in such cases, on ordinary principles the exception to the definition of 'minerals' should be interpreted as having that effect unless there is something in the language or structure of the Act that requires otherwise. As I shall endeavour to show, no such requirement emerges; to the contrary, the structure of the Act confirms that this was the intention.

Statutory Interpretation implications from the structure of the definitions in s 164(7) of the Act

The 'construction' exception to 'mining operations' 39 It is a principle of statutory interpretation that all the words in a statute should, if possible, be given meaning and effect. In Minister for Resources v Dover Fisheries Pty Ltd (1993) 43 FCR 565 at 574, Gummow J, following Lord Reid in AMP Inc v Utilux Pty Ltd [1972] RPC 103 at 109, observed that it is 'improbable that the framers of the legislation could have intended to insert a provision which has virtually no practical effect' and that 'one should look to see whether any other meaning produces a more reasonable result'. As Pearce and Geddes note in Statutory Interpretation in Australia (5th ed. 2001) at [2.22]: 'this principle is more compelling if the word in question has been added by amendment' (see Transport Accident Commission v Treloar [1992] 1 VR 447 at 462 per Brooking J). 40 As I have mentioned, Adelaide Brighton submitted that the 'limestone exception' applied only to 'mining operations' for the recovery of 'limestone as such' and not to limestone recovered for its mineral content. It relied upon the decision of the Full Court in Goliath, which it submitted was authority (albeit obiter) that the exception only applied to 'limestone as such' (at 18 [29]) and the Court's decision in David Mitchell which, it contended, applied Goliath (at 257-258 [28] - [29]). 41 The problem with this submission is the prior existence of another exception to the definition of 'mining operations'. Between 1986 and 1997, the last paragraph in the definition of 'mining operations' provided: '"mining operations" means: … but does not include quarrying operations carried on solely for the purpose of obtaining stone for building, road making or similar purposes.' After the amendments introduced by the CELA Act 1997, the definition of 'mining operations provided: '"mining operations" means: … but does not include: (x) quarrying or dredging operations to the extent that the purpose of the operations is to obtain materials for use in building, road making, landscaping, construction or similar purposes;…' 42 If the 'limestone exception' in par (b) of the definition of 'minerals' were limited to exclude only 'limestone as such', in the sense in which Adelaide Brighton has sought to employ the term, it would appear that for most practical purposes the narrowing of the definition of 'minerals' extended no further than the pre-existing exception. It may be that some scope for its operation could be found, but the pre-existing exclusion would seem to have covered most, if not all, practical uses of 'limestone as such'. If Adelaide Brighton's contention were accepted, therefore, the 'limestone exception' would have little, if any, practical effect. It, therefore, becomes necessary to consider whether any other meaning produces a more reasonable result (see Minister for Resources v Dover Fisheries Pty Ltd (1993) 43 FCR 565 at 574). 43 Limestone can be put to numerous uses, but it would seem that, except for its use as rock or crushed rock for use in construction (uses excluded by the 'construction' exception to the definition of 'mining operations'), the chemical or mineral composition of the limestone is relevant to its use. Its composition must surely be relevant in such well-known applications of limestone as the manufacture of lime, cement and soda ash, and in the use of limestone as a flux in the production of glass and the smelting of iron ore. The use of crushed limestone to neutralise acid soils must also surely depend upon the fact that limestone contains alkaline minerals. 44 The circumstance that the chemical or mineral composition of limestone is the basis for many of its well-known applications, and the fact that confining the exception to 'limestone as such' would deprive the exception of much, if not all, of its practical effect, points powerfully to the conclusion that the 'limestone exception' was intended to extend to operations where the limestone, although mined for its mineral or chemical content, has not had any of its constituent minerals extracted from it. There would seem, therefore, to be no basis for concluding that a more reasonable result would be produced by the construction contended for by Adelaide Brighton.

The 'agricultural use limestone' exception to 'mining' 45 The principle that all words of a provision should be given meaning and effect is also relevant in the context of an exception to the exception in the definition of 'minerals'. The amendment to the definition of 'minerals' in the CELA Act 1995 was retrospectively amended by the CELA Act 1996 to remove from the 'limestone exception' what the Act termed 'agricultural use limestone', which is limestone for use in the de-acidification of soil. The explanatory memorandum to the Bill, which became the CELA Act 1996, explained (at 6, 8): 'The combined effect of [the insertion of a definition of agricultural use limestone and the removal of agricultural use limestone from the exception to the definition of 'minerals'] is that Diesel Fuel Rebate eligibility is to be restored, post 1 July 1995, for the extraction of limestone, where that limestone is for use in the de-acidification of soil in agriculture… The purpose of the amendment is to effect the limited restoration of Diesel Fuel Rebate eligibility for diesel fuel used in extracting limestone. As explained in item 9 of this Bill, limestone which is extracted for use in the de-acidification of soil in agriculture is to be restored to eligibility from 1 July 1995, the date of effect of the changed definition.' 46 Plainly enough, limestone is used for the de-acidification of soil because, as a result of its mineral content, it is alkaline. Limestone mined for the de-acidification of soil in agriculture is, thus, not mined for its use as 'limestone as such' (as that term is used by Adelaide Brighton in its submissions) but is mined because its mineral content makes it suitable for that purpose. Although counsel for Adelaide Brighton contended to the contrary, a construction limiting the application of the limestone exception to 'limestone as such' would not, therefore, extend to 'agricultural use limestone'. This would mean that the removal of 'agricultural use limestone' from the exclusion to the definition of 'minerals' by the CELA Act 1996 was unnecessary and of no effect. 47 As in the case of the 'construction' exception, for this provision to have any effect, the term limestone in the 'limestone exception' needs to be construed so as to extend beyond 'limestone as such' to limestone mined for its mineral or chemical content, without the extraction of those minerals. 48 The implications to be drawn from the removal of 'agricultural use limestone' from the 'limestone exception' were discussed by Heerey J in Chief Executive Officer of Customs v Goliath Portland Cement Co Ltd (1999) 29 AAR 182 (the first instance decision appealed from in Goliath). At 186, 187 (omitting the passage holding that the 'limestone exception' necessarily entails the exclusion of calcite, which the Full Court in Goliath found to be incorrect), Heerey J said: 'Goliath's argument requires treating the exclusion as if it read "(other than agricultural limestone or limestone where what is sought is not the limestone as such, but a mineral that is found in the limestone)". To quote the well-known passage from the speech of Lord Mersey in Thompson v Goold & Co [1910] AC 09 at 420: "It is a strong thing to read into an Act of Parliament words which are not there, and in the absence of clear necessity it is a wrong thing to do." This conclusion is confirmed by the restoration of the rebate for limestone but limited to agricultural use limestone… The extrinsic materials relied on cannot alter the meaning of the unambiguous words of the statute: Re Bolton; Ex parte Beane (1987) 162 CLR 514 at 518. Cement manufacture is a well-known use of limestone. It would be an odd reading of the statute to treat limestone as excluded from the exclusion not only where it is sought for the use explicitly mentioned (agriculture) but also for other, and necessarily unspecified, uses. Such other uses would include not only cement manufacture but glass manufacture and medicinal purposes amongst others. A reading which treats limestone as excluded from "minerals" if, but only if, it is for agricultural use, is not absurd, extraordinary, capricious, irrational or obscure: Cooper Brooks (Wollongong) Pty Ltd v Commissioner of Taxation (Cth) (1981) 147 CLR 297 at 304-305 per Gibbs CJ, 319-321 per Mason and Wilson JJ. Nor is there good reason for thinking that this literal reading does not conform to the legislative intent as ascertained from the provisions of the statute, including the policy which may be discerned from these provisions: Cooper Brooks at 321. The present context is a revenue statute which implements policies that some forms of commercial and industrial activity should be treated more favourably than others. Of necessity fine lines have to be drawn… Historical, political and economic factors are at work. The provisions of the statute (as distinct from the extrinsic materials which at the most can only be an aid to the construction of those provisions) do not indicate any policy, other than the obvious one that limestone is only to be treated as a "mineral" when it is for agriculture use.'

Existing Authorities on the 'limestone exception' 49 It is now necessary to consider the two decisions of the Full Court in which the limestone exception has been considered: Goliath and David Mitchell. As I have noted, Customs submits that Goliath should be followed and that David Mitchell should either be distinguished or not followed, whereas Adelaide Brighton submits that there is no conflict and that both cases support a narrow interpretation of the 'limestone exception' to 'limestone as such'. 50 In Goliath, Customs rejected claims for the diesel fuel rebate for fuel used in extracting limestone and clay and in heating the kiln in which the calcite in the limestone was transformed into lime. The Tribunal overturned this decision, holding that the 'limestone exception' did not apply where limestone was being extracted for its mineral content. 51 An appeal to the Federal Court was allowed in part and an order made for the remittal of the matter to the Tribunal for reconsideration. Goliath then appealed to the Full Court, which dismissed Goliath's appeal and upheld the cross-appeal by Customs. It doing so the Full Court said (at 18): '28. In our view it could not be said that in this case lime was a "mineral" which was "recovered". Limestone is certainly recovered and the process which follows may be described as one of beneficiation of the limestone but only as part of a continuous process in the manufacture of cement. At the point of stockpiling of the blend prior to use, it was not suggested that a relevant mineral could be regarded as recovered and in a form to be saleable. The whole process undertaken is one which goes well beyond the removal of impurities to recover any mineral. Whilst the nature of the process applied in recovery will not always be conclusive of the question whether a mineral has been recovered, what is required is that the mineral be present when the material in which it is contained was taken from the earth…' 29. On the view we have taken of the matter it is unnecessary to deal with the question whether the exclusion of "limestone" from the definition of "minerals" carries with it the exclusion of its constituents. Calcite is not the mineral mined or recovered. If that were the case we are however respectfully unable to agree with His Honour the primary judge (with whom Ryan J agreed in David Mitchell) that any more was intended by the exclusion than a reference to limestone as such. An exclusion from beneficial legislation should not, in our view, be read widely unless it is clear that it was intended to incorporate more than is conveyed, namely the stated material. Calcite cannot as a matter of language, be regarded as a derivative of the word limestone (as to which see Pearce and Geddes, Statutory Interpretation in Australia, (4th ed, 1996), par [6.41]). The reference in the exclusion allowing for two constituents of clay should not be regarded as concluding the question whether the constituents of each of the materials there referred to were also to be taken as excluded, unless they were in turn excepted from it. At the most it creates an uncertainty. The extrinsic materials to which regard might then be had to resolve the question show that it was not intended to refuse rebate where a mineral within the stated minerals was sought to be recovered.' 52 The Full Court then expressed the view that it was appropriate to frame orders finally disposing of the matter, rather than remitting it for reconsideration by the Tribunal, 'since it turned upon a question of construction'. 53 Before considering the competing contentions of the parties about the meaning and effect of the judgment in Goliath,it will be helpful to set out the crucial findings of the Tribunal, which the Full Court in Goliath had to consider after it had rejected the primary judge's construction of the 'limestone exception'. 54 The Tribunal's decision in Re Goliath Portland Cement Co and Anor v Chief Executive Officer of Customs (1998) 53 ALD 659 had two limbs. The Tribunal held (at 669, 682): 'We reject the submission that the extraction operations relate to limestone, which has been excluded from the definition of "minerals" since 1 July 1995, on the basis that Goliath mines for calcite, a mineral that is found in the limestone… The tribunal finds that lime is recovered (that is obtained) by separation, in the calcining process and that, therefore, the calcining of calcite contained in limestone constitutes beneficiation of minerals as an integral part of operations for their recovery.' 55 The Full Court, at [28] of its decision in Goliath clearly rejected the Tribunal's reasoning on the second limb. It is less clear, however, how the Full Court addressed the Tribunal's reasoning on the critical first limb and it is in respect of this aspect of the decision that the parties put forward differing interpretations. Customs submitted that the sentence at [29] 'calcite is not the mineral mined or recovered' was a finding of law based on the Court's earlier discussion of the notion of recovery as separation at [24]-[25] and the Court's statement at [27] that 'limestone is certainly recovered'. Adelaide Brighton on the other hand submits that the phrase 'calcite is not the mineral mined or recovered' is simply part of an obiter statement and was unnecessary for the determination of the appeal. 56 What is clear, in my view, is that the Full Court in Goliath proceeded on the basis that the question 'what was Goliath mining for' turned on the construction of the legislation and hence involved a question of law. Had it not proceeded on that basis, it would not have been appropriate for the Court to 'frame orders finally disposing of the matter rather than to remit it for further consideration by the Tribunal' when it had reached a conclusion about calcite that was expressly contrary to the Tribunal's conclusion that: 'Goliath mines for calcite'. 57 The reasoning supporting the Full Court's finding that 'calcite is not the mineral mined or recovered' is not set out in any detail but, it seems to me that nothing in the judgment is inconsistent with the construction of the exception to the definition of 'minerals' that I favour. 58 For these reasons, I must disagree with the learned primary judge's analysis of Goliath. His Honour's reasons seem to me to proceed on the basis that the Full Court in Goliath was only called upon to consider the claim that lime was the 'mineral' recovered. In circumstances, however, where the Tribunal had made an express finding in relation to calcite and the Court determined not to remit the matter for further consideration, but rather to overturn the Tribunal's decision and deny the diesel fuel rebate, the Full Court was obliged to consider and form a view about all of the Tribunal's findings which supported eligibility for the rebate. 59 Another point in the Full Court's judgment in Goliath, which is said to be of importance, is the obiter statement following the finding that 'calcite is not the mineral mined or recovered'. In that passage, the Full Court disagreed with Heerey J's finding that: 'If "limestone" has been expressly excluded from the statutory definition of "minerals" it seems to me to follow inexorably that the essential and defining component of limestone, namely calcite, must also be excluded.'

(see Chief Executive Officer of Customs v Goliath Portland Cement Co Ltd (1999) 29 AAR 182 at 186.)

60 In disagreeing, the Full Court said (at 18 [29]): '…we are however respectfully unable to agree with His Honour the primary judge…that any more was intended by the exclusion than a reference to limestone as such.' 61 As discussed, Adelaide Brighton has sought to argue that the 'limestone exception' is limited to 'limestone as such' and that the phrase 'limestone as such' refers to limestone used for its physical rather than its mineral properties. The Company seeks support for this interpretation from the passage just cited from Goliath. 62 In my view, however, the use of the words 'limestone as such' in this passage cannot bear the meaning contended for by Adelaide Brighton when regard is had to the context in which the words were used. I take the Full Court to have used the expression to differentiate mining operations in which calcite was the material present at their conclusion, from mining operations in which limestone was the material present at their conclusion, irrespective of whether the limestone was mined for its physical properties or mineral content. 63 On this view, the Full Court was doing no more than saying that where calcite was separated from the limestone, it did not fall within the 'limestone exception', contrary to the conclusion that Heerey J had reached. I do not understand the Full Court to have been purporting to resolve the issue in the present case. If it were, then on the facts as found (i.e. Goliath extracted limestone to obtain calcite and subsequently transform it into lime), and applying the limitation on the use of the words 'limestone as such' contended for by Adelaide Brighton, the Court could not have come to the conclusion that 'calcite is not the mineral mined or recovered' (my emphasis), because it was clear that the limestone was in fact mined for its mineral content. 64 The Full Court's decision in Goliath was considered a year later by another Full Court in David Mitchell. David Mitchell's operations were slightly different to those of Goliath in that its extraction of limestone was with a view to producing lime as a final product, rather than as an input for the manufacture of cement. The operations were otherwise very similar. 65 David Mitchell claimed the rebate for diesel fuel used in the extraction of limestone and its further processing into lime. Customs determined that the activities were not 'mining operations' and that David Mitchell was not entitled to the rebate. The Tribunal set aside the decision, decided that the diesel fuel rebate was payable and directed Customs to assess the payments owed. At first instance, an application by way of appeal from the Tribunal's decision succeeded; the primary judge concluding that David Mitchell's operations were within the 'limestone exception'. 66 David Mitchell then appealed to the Full Court, where Spender J (Gyles J agreeing) held (at 257-258): 'The Tribunal found that the purpose of the extraction process was to obtain the mineral calcite and the "extraction process…constitutes 'mining operations". In my opinion, this is a finding of fact that there was mining for the mineral calcite. This finding was open to the Tribunal… The statement in that passage of the [Goliath] Full Court's reasons that "calcite is not the mineral mined or recovered" is a statement inconsistent with the finding of the Tribunal in the present matter. However, the conclusion of the Full Court is that if calcite was the mineral mined or recovered, it is not excluded from being mining operations by the exclusion of limestone from the definition of minerals. It follows that there was no legal error by the Tribunal in its holding that the extraction process at Lilydale and Loongana for the mineral calcite constitutes mining operations with the consequence that those operations attract an entitlement to the diesel fuel rebate.' 67 Spender J, thus, applied the obiter statement of the Full Court in Goliath. His Honour did so on the basis that the question as to what David Mitchell was mining 'for' was one of fact and that the answer that it was mining for calcite was open to the Tribunal. This, however, seems to be inconsistent with the necessary assumption on which the Full Court in Goliath based its judgment, discussed at [56] above. That necessary assumption was that a question of law - in the form of a question of construction - was involved. An answer to that question of construction must necessarily precede the application of the definitions of 'minerals' and 'mining operations' to the facts found by the Tribunal. So it is that the judgment in David Mitchell did not address the question whether or not the Tribunal applied the correct interpretation of s 164(7) of the Act. 68 I should note that it appears that Spender J did not have it drawn to his attention that the statement that 'calcite was not the mineral mined or recovered' was not only inconsistent with the finding of the Tribunal in David Mitchell (as his Honour rightly observed) but that it was also inconsistent with the finding made by the Tribunal in Goliath. Had this been brought to his Honour's attention, it may well have shed a different light on the Full Court's decision in Goliath by revealing that the Full Court in that case must have concluded that a question of law was involved. 69 In my view, the necessary assumption in Goliath that the inquiry as to what a person is mining 'for' involves a question of statutory construction - and hence a question of law - at least where the exception to the definition of 'minerals' may apply is correct. To the extent that this view was departed from in David Mitchell, that departure should not be followed.

Conclusion 70 This analysis of the legal and historical context of the exception to the definition of 'minerals', as well a consideration of its place within the scheme of the relevant parts of the Act, leads me to the conclusion that the Tribunal and the learned primary judge erred in law. To my mind, the history, context and language of the exception point unequivocally to its application to operations such as those conducted by Adelaide Brighton at Klein Point where limestone is extracted, blended and stockpiled for cement manufacture without there being any extraction from the limestone of its constituent minerals. 71 Critically, the Tribunal found (at [50] and [53]), and the parties do not contest, that the mining operations concluded at the point at which the excavated material was stockpiled. The findings of the Tribunal also involved an acceptance that the material in the stockpile was generally known by both Adelaide Brighton and others in the industry as limestone (see at [45]). In my view, the exception to the definition of 'minerals' extends to all situations in which an excepted material is present at the conclusion of the mining operations, whether that material has been extracted for its physical, chemical or mineral properties. 72 The appeal should therefore be allowed. 73 Because the facts are undisputed, and the sole question before the Court concerns the scope of the exception to the definition of 'minerals' and whether the facts as found fall within that scope (a question of law, see Hayes v Federal Commissioner of Taxation (1956) 96 CLR 47 at 51), it is appropriate for this Court to resolve the question and it is unnecessary to remit the matter to the Tribunal for further consideration. 74 I would therefore order that the order of the primary judge made on 5 August 2003 be set aside. In its place, I would order that the appeal from the decision of the Tribunal be allowed, that the decision of the Tribunal given on 14 August 2002 be set aside, and that the decision of the delegate of the Chief Executive Officer of Customs made on 2 April 1996 and the five further decisions made in respect of diesel fuel rebate eligibility for Adelaide Brighton's operations at Klein Point be affirmed. I would also order that Adelaide Brighton pay Customs' costs of the appeal to the primary judge and of this appeal. 75 One other matter should be mentioned. The view I have taken involves an inconsistency between the treatment of limestone and marble (which is accepted to be metamorphosed limestone) in that marble mined for cement manufacture may attract the diesel fuel rebate, whereas limestone mined for the same purpose does not. However, as the primary judge said in Chief Executive Officer of Customs v David Mitchell Ltd (1999) 43 ATR 191 (at 202): 'That anomaly, if it be one, results from the intractable language of the definition of "minerals" and the express exception therefrom of "limestone". If policy considerations mandate the removal of this suggested anomaly, they will be for Parliament, and not the court, to implement.'

76 This difference in treatment prompts me to venture the suggestion that problems of this nature could be resolved by amending the legislation to effect the desired exclusions by specifying activities rather than materials, and by excluding those activities directly from the definition of 'mining operations'. This might lead to greater clarity and understanding of the precise policy objectives of any further amendments to the legislation.

I certify that the preceding seventy-six (76) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Chief Justice Black.

ON APPEAL FROM A JUDGE OF THE FEDERAL COURT OF AUSTRALIA

JUDGES: BLACK CJ, TAMBERLIN, SACKVILLE, FINN & SELWAY JJ

the appeal 77 In this appeal the question is whether the open cut removal and handling of what the primary Judge referred to neutrally as 'limestone material' from the respondent's mine at Klein Point in South Australia qualifies for a diesel fuel rebate. This depends on whether the respondent ('Adelaide Brighton') purchased diesel fuel for use in 'mining operations' as defined in s 164(7) of the Customs Act 1901 (Cth) ('the Act'). 78 The dispute between the parties relates to Adelaide Brighton's applications for diesel fuel rebates during the period from July 1995 until an unspecified date in 2001. The definition of 'mining operations' in s 164(7) of the Act was amended from 1 August 1997. However, at all material times it has included 'mining for minerals'. The definition of 'minerals' includes minerals in any form except, inter alia, 'limestone (other than agricultural use limestone)'. 79 The primary Judge dismissed an appeal on a question of law under the Administrative Appeals Tribunal Act 1975 (Cth) ('AAT Act') to a decision of the Administrative Appeals Tribunal ('AAT'). The AAT upheld the entitlement of Adelaide Brighton to a diesel fuel rebate for its operations 'up to and including its stockpiling the recovered material at Klein Point'. The critical finding by the AAT was that Adelaide Brighton was not mining the limestone material 'for its being limestone', but for the four specific compounds the particular limestone contains, namely calcite, silica, alumina and haematite. His Honour considered that this finding was open to the AAT. He held that the AAT was not obliged to conclude, simply because the four minerals happened to be found in limestone, that Adelaide Brighton was mining for limestone. Accordingly, the exception to the definition of 'minerals' did not apply and the AAT's decision was not affected by any error of law. 80 According to the appellant, two decisions of the Full Court dealing with the definitions of 'mining operations' and 'minerals' are in conflict. The appellant argued that the decision in Goliath Portland Cement v Chief Executive Officer of Customs (2000) 101 FCR 11, precluded the AAT from making the finding that it did. Mr Robertson SC, who appeared with Mr Williams SC and Dr Gelbart for the appellant, contended that to the extent that the later decision of the Full Court in David Mitchell Ltd v Chief Executive Officer of Customs (2001) 107 FCR 252, is inconsistent with Goliath, it should not be followed. Accordingly, so he argued, the primary Judge was in error in failing to follow Goliath. 81 Although the argument in this case ranged widely, the point is a short one. The appellant's position is that where a miner recovers limestone, but none of the compounds constituting the limestone is ever separated from the limestone, the exclusion from the definition of 'minerals' applies and consequently the miner is not engaged in 'mining operations' for the purposes of the Act. Mr Robertson accepted that if the miner takes measures to separate some or all of the mineral compounds comprising the limestone in order to recover those compounds, it cannot be said that the operations are for the recovery of limestone. But since Adelaide Brighton did not separate out any of the four mineral compounds, its operations, as a matter of law, could only be characterised as being for the recovery of limestone. 82 Adelaide Brighton's position is that the legislation, having regard to its history, should be interpreted as distinguishing between limestone extracted for use as such and limestone extracted for its mineral properties. The former is caught by the exclusion in the definition of 'minerals'; the latter is not. Since Adelaide Brighton did not seek to use the limestone as such, the AAT was entitled to make the finding it did. The finding was simply one of fact that cannot be challenged in proceedings under the AAT Act.

the legislation 83 Section 164(1)(a) of the Act provides that a diesel fuel rebate is, subject to certain immaterial conditions, payable to a person who purchases diesel fuel for use by him (or her) 'in mining operations'. Where a person purchases diesel fuel for use in this manner, but in fact uses the fuel in a different manner, any rebate paid in respect of the fuel is to be refunded: s 164(2). 84 For the period from 1 July 1995 to 31 July 1997 'mining operations'was defined in s 164(7) of the Act to mean: '(a) exploration, prospecting, or mining for minerals, or the removal of overburden and other activities undertaken in the preparation of a site to enable mining for minerals to commence; or (b) the dressing or beneficiation of minerals, or ores bearing minerals, as an integral part of operations for their recovery;… … but does not include quarrying operations carried on solely for the purpose of obtaining stone for building, road making or similar purposes.' From 1 August 1997, the definition was amended by the Customs and Excise Legislation Amendment Act (No 1) 1997 (Cth) to read, so far as relevant: '(a) exploration or prospecting for minerals, or the removal of overburden and other activities undertaken in the preparation of a site to enable mining for minerals to commence; or (b) operations for the recovery of minerals, being: (i) mining for those minerals including the recovery of salts by evaporation; or (ii) the beneficiation of those minerals, or of ores bearing those minerals; … but does not include: (x) quarrying or dredging operations to the extent that the purpose of the operations is obtain materials for use in building, road making, landscaping, construction or similar purposes…' 85 The definition of 'minerals' in s 164(7) of the Act has been in the same form since 1 July 1995, when it was amended by the Customs and Excise Legislation Amendment Act 1995 (Cth). The definition is as follows: 'minerals means minerals in any form, whether solid, liquid or gaseous and whether organic or inorganic, except: (a) sand, sandstone, soil, slate, clay (other than bentonite or kaolin), basalt, granite, gravel or water; or (b) limestone (other than agricultural use limestone).' 86 Initially, all limestone was excluded from the definition of 'minerals', but the words in parentheses '(other than agricultural use limestone)'were inserted by the Customs and Excise Legislation Amendment Act (No 1) 1996 (Cth), which took effect retrospectively from 1 July 1995. The term 'agricultural use limestone' is relevantly defined to mean 'limestone for use in the de-acidification of soil in any agricultural activity'.

factual findings 87 The following account of the facts is based on the findings of the AAT. 88 Klein Point is located on South Australia's Yorke Peninsula. It lies on an extensive, flat-lying tabular limestone deposit of marine origin. Adelaide Brighton has been conducting operations in the Klein Point area since 1917. At the relevant times, Adelaide Brighton operated Mining Lease 5881 which permitted it to conduct mining operations for the recovery of limestone. The Klein Point site is commonly referred to as a quarry. 89 Limestone is a sedimentary rock containing more than 50% of calcium carbonate. Generally, but not always, the calcium carbonate is present in the form of the crystalline mineral calcite. 90 Adelaide Brighton requires particular compounds in specified proportions for the manufacture of cement at its plant at Birkenhead, 40 kilometres from Klein Point across the Gulf of St Vincent. The compounds it requires include calcium carbonate (commonly known as calcite) (CaCO3), silicon dioxide (commonly known as silica) (SiO2), aluminium oxide (commonly known as alumina) (A12O3) and ferric oxide (commonly known as haematite) (Fe2O3). Each of these compounds is a mineral. 91 Adelaide Brighton seeks to produce material from its operations at Klein Point in the following proportions: calcite (85%), silica (10.5%), alumina (1.5%) and haematite (1.2%). Other compounds are contained within the limestone excavated at Klein Point and Adelaide Brighton Cement seeks to limit the amounts of those compounds that it regards as deleterious to its cement production. Those compounds and their upper limits are magnesium (1.2%) and potassium and sodium (combined limited of 0.36%). In some areas of the quarry, the material excavated comprises up to 3.0% magnesium and up to 1.2% of potassium and sodium. 92 The material obtained by Adelaide Brighton from Klein Point is known generally in the industry as limestone. However, it is only limestone with particular qualities that suits Adelaide Brighton's needs. Such limestone is known as 'cement grade limestone'. 93 The raw material used in the manufacture of cement generally includes limestone, since it contains not only calcite but, usually, some of or all the other three required compounds. However, other sources for the compounds may be used. For example, calcite can be obtained from shell sands, such as those recovered from Cockburn Sound in Western Australia by Adelaide Brighton for its cement works at that location, and from marble, which Adelaide Brighton purchases for its cement works at Angaston in the Barossa Valley. 94 The first step in recovering material from the quarry at Klein Point is to remove topsoil from the site. Some two to three meters of hard rocky limestone known as 'kunkar' is located beneath the topsoil. It is drilled and blasted and then discarded. 95 The excavated limestone is stacked in two pre-crusher stockpiles. The material is crushed at a hammer mill and then loaded for transportation by ship to Birkenhead. None of the locations at the quarry contains material comprising the proportions sought by Adelaide Brighton for its cement production at Birkenhead. It achieves the balance it seeks by planning for the construction of the pre-crusher stockpile, and monitoring the grade of the stockpiles on a daily basis by X-ray fluorescence analysis ('XRF analysis'). 96 At Birkenhead, the material is transported by conveyors to the pre-blend building, where it is stockpiled. Shale, sand and iron oxide are added by means of an automatically controlled proportionary system. The resulting mixture undergoes a series of processes to produce cement. 97 The AAT was satisfied that Adelaide Brighton 'does not separate all or any of the four minerals from each other. It does not need to separate them for the purposes for which it uses them i.e. in the production of cement. All that it requires is that the four minerals be present in the materials in the specified proportions and within the specified maximum levels of impurities so that they may undergo certain chemical reactions with other compounds and lead ultimately to the production of clinker. Further physical processes lead to the production of cement. I am satisfied, therefore, that the ultimate purpose of Adelaide Brighton Cement in mining the limestone is for use in its cement works at Birkenhead for the production of cement. It is not for the recovery of calcium carbonate, silica, alumina and haematite'. 98 It was also satisfied that in extracting the material at Klein Point, Adelaide Brighton was mining for minerals, those minerals being calcite, silica, alumina and haematite. It was not mining that material for limestone. If Adelaide Brighton were doing that, it would have no need to discard the kunkar or to test the remaining limestone to ensure that it meets the required standards.

reasoning of the aat 99 The AAT identified two issues for resolution. The first was whether Adelaide Brighton's operations at Klein Point constituted 'mining for minerals' so that they were 'mining operations' as that term is defined in s 164(7) of the Act. If this question was answered affirmatively, the second issue arose. This was whether the material for which Adelaide Brighton mined at Klein Point was limestone and so excluded from the definition of 'minerals' in the Act. The AAT therefore considered it necessary to ascertain the minerals for which Adelaide Brighton was mining. 100 The AAT observed that the concept of the recovery of minerals is the 'central point of reference' for the definition of 'mining operations': State Rail Authority (NSW) v Collector of Customs (1991) 33 FCR 211, at 215, per curiam. 101 There was no dispute before the AAT that quarrying is encompassed within the word 'mining'. On the factual findings it had made, the AAT took the view that Adelaide Brighton was mining for the four specific compounds contained in the limestone. Leaving aside the exclusion of limestone from the definition of 'minerals', it followed that Adelaide Brighton was entitled to be paid the rebate on all activities, but only up to the point of stockpiling. Since the processes undertaken after stockpiling were directed to the use of the minerals in the manufacture of cement and not to improving the properties of the minerals, Adelaide Brighton was not entitled to the rebate for any fuel used in processes after that point. 102 The AAT dealt with the exclusion of limestone as follows: 'But for the exclusion of limestone from the definition of minerals, it would follow that [Adelaide Brighton] is entitled to a diesel fuel rebate up to and including its stockpiling the material at Klein Point. Does the exclusion of limestone disentitle it? In view of the findings that I have already made, I do not consider that it does. I have found that [Adelaide Brighton's] object in mining is not limestone. Indeed, it discards some of the limestone as suitable only for land re-examination [sic - reclamation]. Its operations I have found are for the recovery of calcite, alumina, silica and haematite. They are not for the recovery of limestone. The fact that limestone does or may contain those four minerals does not detract from this finding. The section focuses on [Adelaide Brighton's] operations and on what those operations are for. It does not focus on whether the minerals sought by [Adelaide Brighton] are found in limestone and disentitle the company to a diesel fuel claim on that basis.'

THE SUBMISSIONS 103 The appellant accepted that the recovery of minerals is the central concept in the definition of 'mining operations'. According to Mr Robertson, operations for the recovery of minerals are complete when no further processes are undertaken to separate the mineral from that in which it is embedded or intermixed. Accordingly, the appellant did not challenge the AAT's finding that the recovery process in the present case ceased when the excavated limestone was stockpiled. 104 However, in the light of these principles, so Mr Robertson argued, the exclusion of limestone from the definition of 'minerals' operates in a straightforward way. The application of the exclusion should be considered at the stage when any process of separation, that is recovery, of the minerals is complete. If limestone is extracted from the soil, the exclusion of 'limestone (other than agricultural limestone)' from the definition of 'minerals' must apply unless:

• the limestone is 'agricultural use limestone'; or
• a mineral or minerals is subsequently separated from the limestone, so that minerals are recovered in a form other than limestone. 105 Having correctly found that the recovery process concluded at the point of stockpiling, the AAT should simply have asked itself whether the recovered material in the stockpile was 'limestone (other than agricultural use limestone)'. If the answer was yes, as it clearly was, the limestone exclusion applied. 106 The appellant submitted that the AAT had erred in law because it applied the wrong test. It 'was not helpful' for the AAT first to ask itself whether the operations were 'mining for minerals' and then whether the excavated material was limestone. 107 Adelaide Brighton submitted that it did not seek to obtain limestone as such from its Klein Point operations. Rather, it sought the four minerals contained in the limestone. It would not matter, for Adelaide Brighton's purposes, if those minerals were obtained from other sources such as marble, which is a source of calcite. 108 According to Mr De Wijn QC, who appeared with Ms Harris for Adelaide Brighton, the AAT was bound to ask itself what Adelaide Brighton was mining for and then to ask whether that material satisfied the definition of 'minerals' in s 164(7) of the Act. The exclusion of 'limestone' from the definition was said to be intended to exclude only limestone 'as such'. Mr De Wijn relied on the unchallenged factual finding of the AAT that Adelaide Brighton was mining for calcite, silica, alumina and haematite. He submitted that it necessarily followed from this finding that the exclusion did not apply.

the separation issue 109 As Adelaide Brighton pointed out, the AAT made a critical finding that in carrying on its operations at Klein Point, Adelaide Brighton was mining for four minerals, namely calcite, silica, alumina and haematite. The AAT also found that although the material excavated at Klein Point is known generally as limestone, Adelaide Brighton did not mine that material for limestone. These findings formed the basis for the AAT's conclusion that Adelaide Brighton's operations were 'mining operations' as defined in s 164(7) of the Act. In particular, they formed the basis for the AAT's conclusion that Adelaide Brighton was not mining for limestone at Klein Point and therefore the exclusion in par (b) of the definition of 'minerals' in s 164(7) of the Act did not apply. 110 Unless the AAT has committed an error of law (which can include asking itself the wrong question), there is no ground for overturning the primary Judge's dismissal of the application under s 44 of the AAT Act. The only ground that was suggested on behalf of the appellant was that the AAT had failed to recognise that s 164(7) of the Act compelled the conclusion that when Adelaide Brighton extracted limestone it was 'mining' for limestone, unless it separated the compounds comprising the limestone no later than the point of stockpiling. 111 The Act does not state that operations cannot be for the recovery of minerals unless those minerals are separated from the soil or from other minerals, whether at the point of stockpiling or at any other time. Section 164(1)(a) provides that the diesel fuel rebate is payable to a person who has purchased diesel fuel for use in 'mining operations'. The current definition of 'mining operations' requires the decision-maker to consider, in a case such as the present, whether the person has engaged in 'operations for the recovery of minerals being…mining for those minerals'. In view of the exclusions from the definition of 'minerals', the decision-maker must also consider whether the mining has been 'for' any of the excluded minerals, one of which is limestone. 112 The appellant's reliance on the notion of 'separation' of minerals appears to derive from authorities that have incorporated references to the separation of minerals in their reasoning. For example, in Federal Commissioner of Taxation v Broken Hill Proprietary Co Ltd (1969) 120 CLR 240, cited by the appellant, Barwick CJ, McTiernan and Menzies JJ said this (at 273): 'We do not doubt that to separate what it is sought to obtain by mining from that which is mined with it, e.g., the separation of gold from quartz by crushing etc, or the separation of tin from dirt by sluicing, is part of a 'mining operation' but we would not extend the conception to what is merely the treatment of the mineral recovered for the purpose of the better utilization of that mineral.' 113 In the BHP Case, the Court was concerned with the undefined expression 'mining operations' in s 122(1) of the Income Tax and Social Services Contribution Assessment Act 1936 (Cth). Their Honours were not suggesting that the separation of minerals from other minerals is a necessary part of mining operations, let alone that the separation of minerals is an essential element of 'mining…for minerals' as that expression is used in the Act. They were simply giving an illustration of work done by an operator after the excavation of material from the soil that is embraced by the expression 'mining operations'. Their Honours wished to distinguish between processes involving the separation of minerals (like gold from quartz), which are part of mining operations, and processes such as crushing bluestone for road making, which take place after mining operations have ceased. As was said by Ryan and Cooper JJ in Abbott Point Bulk Coal v Collector of Customs (1992) 35 FCR 371, a case concerned with s 164(7) of the Act (at 379): 'Once the process of separation or refining has been completed, to subject the mineral product to a process or procedure designed purely to facilitate its better use as so separated or refined or to render it more readily or advantageously marketable is not in our view part of the recovery process.' That is a different proposition from the one advanced by the appellant, namely that there can be no recovery of a particular mineral without that mineral being physically separated from others that may be excavated at the same time. 114 An operator may excavate limestone with a view to stockpiling and using or marketing the product so excavated, for example for building purposes. The operator may have little or no concern about the precise mineral content of the limestone. In these circumstances, there can be little doubt that the operations should be characterised as mining for limestone. This is so notwithstanding that the particular limestone comprises a number of identifiable mineral compounds. The operations would therefore be caught by the exclusion in par (b) of the definition of 'minerals' in s 164(7) of the Act and the diesel fuel rebate would not be payable. 115 An operator may, however, excavate limestone with a view to recovering and using the particular mineral compounds found in the limestone. Sometimes it may be quite clear that the operations are for the recovery of one or more of the particular compounds. Other cases, for example when the operator claims to excavate limestone in order to utilise the particular mineral compounds found in the ore body, as distinct from the limestone as such, may present much more difficult questions of characterisation. It may be that the evidence in a particular case is such that a decision-maker could reasonably reach either conclusion.

a factual determination 116 In the present case, the AAT, having found that Adelaide Brighton was mining for minerals, sought to identify the minerals for which Adelaide Brighton was mining. This was the correct question for it to address. In answering that question the AAT took into account a number of matters, including the following:

• Adelaide Brighton did not seek to recover limestone as such from its Klein Point quarry, as demonstrated by the fact that it discarded the kunkar;
• Adelaide Brighton required the four mineral compounds contained in the limestone it retained, namely calcite, silica, alumina and haematite, in particular proportions in order to supply its cement operations;
• Adelaide Brighton planned its quarrying operations so as to produce stockpiles of the required grade and continually analysed the composition of the pre-crusher stockpiles to ensure that they met the requirements, making adjustments when required;
• limestone is not the only source of calcite and indeed Adelaide Brighton obtains supplies of calcite from other sources, such as shell sands and marble;
• the other mineral compounds found in Klein Point limestone are generally but not always found in limestone, and are found otherwise than in limestone (for example, silica is found in clay);
• limestone need not contain alumina, silica or haematite;
• expert evidence, for example from Mr Hunter, an experienced mining engineer, that the minerals sought at Klein Point are calcite, silica, alumina and haematite and that considerable time and effort are devoted to ensuring that they are present in the correct proportions and that other minerals found in the limestone are diluted by blending; and
• the concession by Mr Loomes, an expert witness called by the appellant, that limestone by itself is 'very, very rarely ever suitable for cement manufacture'. 117 The AAT had to weigh these matters against other considerations, such as the absence of a process designed to separate any of the four minerals and the fact that Adelaide Brighton described its operations as mining for limestone. None of these considerations was, however, decisive. In our view, it was open to the AAT to conclude that Adelaide Brighton's operations involved mining for the four particular mineral compounds rather than limestone. 118 As a Full Court of this Court has recently observed, the 'differences between questions of law, fact and mixed fact and law can be difficult to rationalise': Cakmak v Minister for Immigration & Multicultural & Indigenous Affairs (2003) 75 ALD 478, at [51]; see too, Collector of Customs v Agfa Gevaert Ltd (1996) 186 CLR 389, at 395-396, per curiam. The question whether facts as found answer a statutory description or satisfy statutory criteria is generally a question of law: Vetter v Lake Macquarie City Council (2001) 202 CLR 439, at 450, per Gleeson, Gummow and Callinan JJ. A question of law will also arise when competing constructions of a statutory expression are put forward, only one of which can be correct: see, for example, Industry Research and Development Board v Bridgestone Australia Ltd (2001) 109 FCR 564, at 576-579, per Lindgren J (with whom Branson and Mansfield JJ agreed). But when a statute uses words according to their ordinary meaning and it is reasonably open to the decision-maker to find that the facts of the case fall within those words, the question whether they do or not is one of fact: Hope v Bathurst City Council (1980) 144 CLR 1, at 8, per Mason J, citing NSW Associated Blue-Metal Quarries Ltd v Federal Commission of Taxation (1956) 94 CLR 509, at 512, per Kitto J; Collector of Customs v Agfa Gevaert Ltd (1996) 186 CLR 389, at 395, per curiam. 119 There was no suggestion that the words in s 164(7) of the Act, including the word 'limestone', were used otherwise than in their ordinary sense. Once it is accepted that, contrary to the appellant's submissions, the AAT did not misconstrue the language of s 164(7) and asked itself the correct question, it was reasonably open to it to conclude that Adelaide Brighton was mining for the four minerals it required rather than for limestone. While not every decision-maker may have reached that conclusion, it was a finding of fact open to the AAT. 120 The conclusion that the AAT committed no error of law does not necessarily mean that every operation involving the mining of limestone for use in the production of cement is to be regarded as mining for minerals other than limestone. Each case must depend on the evidence and its own circumstances. In particular, other cases may not have the features that persuaded the AAT in the present case to make the critical factual findings in Adelaide Brighton's favour.

extrinsic materials 121 Section 15AB(1) of the Acts Interpretation Act 1901 (Cth) permits consideration to be given to the relevant explanatory memorandum or second reading speech if the provision is ambiguous or to 'confirm that the meaning of the provision is the ordinary meaning conveyed by the text of the provision taking into account its context in the Act and the purpose or object underlying the Act'. Although the conclusion we have reached on the question of construction raised by the appellant does not depend on any extrinsic materials, it receives support from the second reading speech and explanatory memorandum. 122 The exclusion of limestone (among other minerals) from the definition of 'minerals' in s 164(7) of the Act was brought about by the Customs and Excise Legislation Amendment Act 1995 (Cth). The second reading speech of the Minister identified four principal changes effected by the legislation, one of which was as follows: 'the narrowing of the definition of "minerals" in the Customs Act 1901 so as to exclude from rebate eligibility diesel fuel used in the mining for minerals, where those operations simply involve the extraction of sand, sandstone, soil, clay, granite, water and the like, from 1 August 1986…' (Emphasis added.) The Minister subsequently expanded on the reasons for the amendment: 'Until recently, the Administrative Appeals Tribunal and the Federal Court have held the view that the term "mining for minerals" in the [A]ct's definition of "mining operations" introduced a purposive test requiring a rebate claimant to demonstrate that the purpose of the claimant's operations was to obtain a mineral or minerals embedded in the material that was extracted. For instance, there was a clear distinction between the extraction of sand per se and the extraction of sand with a view to obtaining from it minerals such as rutile, zircon or almandite. The meaning of "mining operations" was therefore considered to be reasonably well settled until a recent decision of the Administrative Appeals Tribunal on the issue of extracting sand for use in the making of concrete or for use as bedding sand in the construction industry. The Tribunal decided that the extraction of such sand was eligible for rebate. Claims have also been received for rebate on diesel fuel used in the pumping of ground water to be supplied as drinking water to towns. These are, in the Government's view, uses well beyond the intent of the Scheme, which was and is to deliver an assistance measure to mainstream mining pursuits. Accordingly, in item 7 of Schedule 1 to the bill, the Government has proposed to amend the definition of "minerals" to exclude sand, sandstone, earth, soil, slate, clay (other than bentonite or kaolin), basalt, granite, gravel, limestone or water. The exclusion is consistent with the principal mining legislation of the States and would bring about a transparent distinction between mining for minerals and operations that cannot, in the ordinary sense, be regarded as mining. Where these materials are extracted for the purpose of recovering a mineral, the extraction will remain eligible for rebate.' 123 The explanatory memorandum identified the purpose of the amendment to the definition of 'minerals' as follows: '[The] purpose of the amendment proposed in this item is to exclude from eligibility for the payment of rebate diesel fuel for use in extracting certain materials from the ground because they are valuable as extracted, rather than for the purpose of recovering their inherent mineral qualities. For example the use of diesel fuel in the mining of sand for its use in concreting, rather than for the purpose of extracting the minerals contained in the sand, is to be excluded from eligibility for rebate.' (Emphasis added.) 124 These extrinsic materials suggest that the amendment was intended to exclude operations for the recovery of certain minerals, including limestone, that are valuable in the form in which they are extracted from the ground. Thus if limestone were extracted and used for building materials in road works, the intention was that the fuel rebate would not be payable in connection with the mining operations. However, it was not intended to exclude from the rebate operations to extract limestone which was sought for its 'inherent mineral qualities'. While this distinction is not precise, it suggests an intention that the rebate should be payable in connection with mining operations designed to produce a blend of particular mineral compounds that are found in a particular limestone, but not necessarily in the proportions required by the operator.

THE AUTHORITIES 125 There is in our view nothing in Goliath v Customs inconsistent with the conclusion we have reached. The issue presented on the appeal in Goliath was whether the primary Judge erred in construing the statutory exclusion of limestone from the definition of 'minerals' to extend to lime. The lime was produced from a blend of limestone and clay by a process known as 'calcining'. By this process, the blend was heated and the calcium carbonate (calcite) was 'disassociate[d] into calcium oxide (lime)'. The Full Court (at 18) held that the lime could not be regarded as a 'mineral' which was 'recovered' by the operations. Their Honours considered it essential that the mineral be present when the material in which it is contained is taken from the earth. The ratio of the case is not germane to the issue raised in the present case. 126 The Full Court in Goliath stated that it was unnecessary to deal with the question of whether the exclusion of 'limestone' from the definition of 'minerals' carried with it the exclusion of its constituents. Their Honours went on to say this (at 18): 'Calcite is not the mineral mined or recovered. If that were the case we are however respectfully unable to agree with his Honour the primary judge (with whom Ryan J agreed in David Mitchell) that any more was intended by the exclusion than a reference to limestone as such. An exclusion from beneficial legislation should not, in our view, be read widely unless it is clear that it was intended to incorporate more than is conveyed, namely the stated material.' 127 The latter part of this passage is entirely consistent with the approach we have taken in the present case. With respect, it is not entirely clear what their Honours intended to convey by the statement that 'calcite is not the mineral mined or recovered'. If it was intended to be a factual finding, it appears to have been inconsistent with a finding made by the AAT in that case: Re Goliath Portland Cement Co v Chief Executive Officer of Customs (1998) 53 ALD 659, at 669. Be that as it may, we do not read the observation as a holding on any question of law. The Full Court in David Mitchell v Customs considered that the observation in Goliath presented no obstacle to a holding that it was open to the AAT in that case to find that the purpose of extracting limestone was to obtain the mineral calcite (at 257).

conclusion 128 The appeal must be dismissed. The appellant must pay Adelaide Brighton's costs. I certify that the preceding fifty-two (52) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justices Tamberlin, Sackville and Finn.

ON APPEAL FROM A JUDGE OF THE FEDERAL COURT OF AUSTRALIA

JUDGES: BLACK CJ, TAMBERLIN, SACKVILLE, FINN & SELWAY JJ

REASONS FOR JUDGMENT SELWAY J 129 The appellant appeals from the decision of the primary Judge (Chief Executive Officer of Customs v Adelaide Brighton Cement (2003) 75 ALD 478). The primary Judge dismissed an 'appeal' from the Administrative Appeals Tribunal ('the AAT'). The AAT had held that the respondent was entitled to a rebate of the diesel fuel excise because it was carrying on 'mining operations' in quarrying limestone material for use in cement production. The question in issue before the AAT was whether, for the purpose of the relevant statutory definitions, the respondent was mining for minerals other than limestone. The AAT decided that the respondent was mining for the various component minerals within the limestone material that the respondent mined at its quarry. The primary Judge agreed. For the reasons given below I am of the view that the AAT came to the wrong conclusion because it made an error of law. For that reason I would allow the appeal and remit the matter back to the AAT for further consideration. 130 The facts upon which this appeal is brought are not in dispute. For my purposes they can be summarised shortly. The appellant manufactures cement. For this purpose it requires 4 minerals: calcite, silica, alumina and haematite. These minerals, particularly calcite, are contained in limestone. They may be found elsewhere. Calcite, for example, is also contained in marble and shell sands and the appellant has also obtained calcite from these sources. Nevertheless, in order to obtain calcite and the other minerals referred to above for the purpose of manufacturing cement the appellant extracts limestone material from a quarry it operates at Klein Point. The mining operations are open cut operations. The top soil and the hard limestone immediately below it (called 'kunkar') is extracted and discarded. The limestone immediately below that is tested for appropriate levels of the 4 required minerals. It appears that the limestone is mixed with other limestone from elsewhere in the quarry to ensure that the resulting mixture is consistent for the respondent's purposes. Assuming that the limestone meets the required specifications ('cement-grade limestone') the limestone is stored and used in cement production. Any limestone that does not meet those standards is discarded. At no stage are any of the four minerals physically separated from the remainder of the ore that is generally described as 'limestone' or, more particularly, 'cement grade limestone'. 131 The legal issue arising from those facts is whether the appellant is entitled to a diesel fuel rebate. In carrying out its quarrying activities at Klein Point, and in its subsequent use of cement grade limestone, the appellant used diesel fuel. It paid excise tax in relation to the purchase of that fuel. However, it is accepted by the parties that the appellant is entitled to a rebate of the duty it has paid if the diesel fuel was used 'in mining operations': see s 164(1)(a) of the Customs Act 1901 (Cth) (the Act). Hence, its eligibility for the diesel fuel rebate claimed depends on the respondent having used the diesel fuel in 'mining operations'. That term is defined in s 164(7) of the Act. 132 The definition changed with effect from 31 July 1997, but the parties are agreed that the changes are of no particular significance to the issues before the Court. It is sufficient to set out the current definition: 'mining operations means: (a) exploration or prospecting for minerals, or the removal of overburden and other activities undertaken in the preparation of a site to enable mining for minerals to commence; or (b) operations for the recovery of minerals, being: (i) mining for those minerals including the recovery of salts by evaporation; or (ii) the beneficiation of those minerals, or ores bearing those minerals; …' 133 As might be expected the term 'mining operations' is defined in relation to the extraction of 'minerals'. That word is also defined in s 164(7) of the Act. The definition is a broad one encompassing, for example, liquid and gaseous substances. At all relevant times the definition was: 'minerals means minerals in any form, whether solid, liquid or gaseous and whether organic or inorganic, except: (a) sand, sandstone, soil, slate, clay (other than bentonite or kaolin), basalt, granite, gravel or water; or (b) limestone (other than agricultural use limestone).' 134 The dispute between the parties is limited to the effect of par (b) of this definition. The appellant accepts that, but for that par, the respondent was carrying on 'mining operations' in quarrying for limestone at Klein Point. In particular the appellant accepts that 'limestone' used in cement production would be a 'mineral' for the purpose of the relevant definition if the exception to the definition of 'minerals' did not include par (b) (contrast North Australian Cement Limited v Federal Commissioner of Taxation (1969) 119 CLR 353 ('North Australian Cement No 1')with North Australian Cement Limited v Federal Commissioner of Taxation (1989) 89 ATC 4765 ('North Australian Cement No 2')). Given the breadth of the current definition, and the specific exclusion of 'limestone', that concession is properly made, whatever might be the position in other contexts. 135 However, the appellant says that the mining operations were to extract limestone within the terms of par (b) and that consequently the operations were not 'mining operations' as defined and the diesel fuel rebate is not applicable. The respondent, on the other hand, says that it was not seeking to extract 'limestone' but rather the 4 minerals comprised within it. The respondent says that it was carrying out mining operations and is entitled to the rebate. 136 The dispute was ultimately considered by the AAT. It identified the question that it had to resolve as being 'the identification of the minerals for which Adelaide Brighton Cement was mining'. In a careful and detailed decision the AAT reached the view that the separation of the kunkar from the rest of the limestone showed that the respondent was not seeking to extract mere limestone, but was seeking to extract the 4 minerals as it claimed. Consequently, the AAT held that the respondent was entitled to a diesel fuel rebate in relation to diesel used in the 'mining operation'. There was also an issue before the AAT as to the extent of that mining operation, but that aspect of its decision has not been subject to any review and need not concern this Court. 137 The appellant 'appealed' to this Court from the decision of the Tribunal: see s 44 Administrative Appeals Tribunal Act 1975 (Cth) ('the AAT Act'). In relation to such an 'appeal' the jurisdiction of this Court is limited to the correction of errors of law. The 'appeal' was dismissed at first instance. The primary Judge held that there had been no error of law by the AAT. The appellant appeals to this court from that decision. In essence the appellant repeats the argument it put to the primary Judge - on the facts as found it was an error of law to conclude that the respondent was entitled to a diesel fuel rebate. 138 Both the AAT and the primary Judge relied upon two previous decisions of this Court: Goliath Portland Cement v Chief Executive Officer of Customs (2000) 101 FCR 11 ('Goliath')and David Mitchell Ltd v Chief Executive Officer of Customs (2001) 107 FCR 252 'David Mitchell'). The primary Judge carefully considered both decisions in his reasons. The appellant has argued before this Court that these two decisions are inconsistent and that David Mitchell should not be followed. The practice in this Court, even when sitting as a Full bench of 5 Justices, is that previous Full Court decisions should be followed unless those decisions are 'plainly wrong' or unless there are inconsistent Full Court decisions: see Transurban City Link Ltd v Allan (1999) 95 FCR 553. Consequently the question of whether the previous decisions are inconsistent is important in determining what answer should be given on this appeal. It will be necessary to return to this issue below. 139 I remind myself that the identification of the correct meaning of a statute (and of the words and phrases within it) is a question of law. On the other hand where the correct meaning of a particular word is its usual or ordinary meaning then the question whether particular facts fall within that meaning is usually a question of fact. See generally Hope v Bathurst City Council (1980) 144 CLR 1 at 7-8; Collector of Customs v Agfa-Gevaert Ltd (1996) 186 CLR 389 ('Agfa-Gevaert') at 394-396. Of course a determination that particular facts fall within the 'usual meaning' of a word or phrase may disclose that the decision maker has not properly interpreted the statute in which case a decision which might otherwise be characterised as one of fact nevertheless involves an error of law. 140 I turn then to the correct legal interpretation of the relevant statutory provisions. The first thing to note about the correct meaning of the provisions is that the availability of the rebate is dependent upon the identification of the subjective purpose of the purchaser. Under s 164(1) of the Act the rebate is payable to a person who purchases diesel fuel 'for use by him in mining operations'. (Although, if ultimately used for a different purpose, the rebate is repayable: see s 164(2).) Plainly enough the purpose in s 164(1) of the Act is the subjective purpose of the purchaser. 141 Similarly, the use of the word 'mining' in the term 'mining operations' as defined in s 164(7) of the Act suggests strongly that the relevant operations are purposive - the relevant operations are for the purpose of digging in the earth to extract minerals. The definition of 'mining operations' is consistent with this purposive approach. This is shown by the use of the word 'for' throughout the definition. Similarly, the activities referred to are not limited to the extraction or recovery of minerals, but to activities directed to the relevant purpose - exploration, prospecting, removal of overburden and so on. These activities may be preparatory to the creation of a mine, but are directed to the relevant purpose. 142 The relevant purpose is a subjective purpose. Subject to the comments below, the determination of subjective purpose is a determination of a fact. The relevant fact would normally be proven by establishing what is actually done, on the basis that the best evidence of a person's purpose is usually what the person actually does. However, the real possibility exists, particularly at a stage preparatory to actual mining, that a person's purpose might be to mine for a mineral or minerals even if no particular minerals are ultimately recovered, or indeed, if quite different minerals are ultimately recovered. At the stage of exploration, for example, the explorer's subjective purpose may be to explore for limestone even though ultimately the person discovers gold, not limestone. Clearly enough evidence of what is recovered will usually be relevant to the question of purpose, but it is not determinative of it. 143 Similarly, the fact that something is actually extracted does not mean that its extraction was the relevant subjective purpose. For example, if nuggets of gold were contained in a body of limestone and the limestone was extracted to get at the gold then, if it were necessary to determine whether the purpose of the mining operations was mining for gold or mining for limestone, it might well be concluded that the relevant subjective purpose was the extraction of gold, not limestone. The extraction of the limestone might well be characterised as either a waste product or a by-product of the gold mining operation. Such an example is sufficiently obvious as to suggest that the correct legal characterisation of the relevant purpose is a simple question of fact. This is because the apparent obviousness of the result may mislead as to the process of legal characterisation involved. 144 As already remarked, the identification of the relevant subjective purpose is a question of fact to be determined in this case by the AAT. However, that statement is subject to the AAT having correctly determined the meaning of 'mining operations' and 'minerals' in the Act so as to enable it to ascertain what the relevant subjective purpose is for the purpose of the Act. The determination by the AAT was not simply one of fact - it also included the correct legal interpretation of the relevant words of the Act. Put that way it is clear that the issue before the AAT was not simply one of fact, but also one of law. 145 Some of the words used in the definition of 'mining operations' may be used in a technical or specialised sense. The word 'beneficiation' is an example: see Abbott Point Bulk Coal v Collector of Customs (1992) 35 FCR 371 at 374. However, both parties agreed that the word 'limestone' in par (b) of the definition of 'minerals' is used in its usual and normal meaning. I agree. Although some more precise definitions were attempted in the evidence given before the AAT, the usual and normal dictionary meaning of the word 'limestone' is 'a rock consisting wholly or chiefly of calcium carbonate'. There is no doubt that what was being extracted from the quarry at Point Klein was properly described as 'limestone'. 146 The Tribunal nevertheless found that the respondent was mining for minerals other than limestone, namely the four minerals, including calcite, contained within the limestone. In my view that finding by the AAT was based upon its assumption that each mineral is mutually exclusive of all other minerals with the consequence that the factual identification of the relevant mineral being sought by the respondent as 'calcite' (or the other three minerals) necessarily meant that it was not 'limestone'. This can be seen in two paragraphs of its reasoning: 'Having regard to all of the material, I find that the material that Adelaide Brighton Cement obtains from Klein Point is generally known both by it and by others in the industry as limestone. It is not, however, mining it for its being limestone. If it were doing that, it would have no need to discard the kunkar or to test the remaining limestone to ensure that it meets certain prescribed standards. I am satisfied that it is mining it for four specific compounds that the limestone contains: calcite, silica, alumina and haematite. …But for the exclusion of limestone from the definition of minerals, it would follow that Adelaide Brighton Cement is entitled to a diesel fuel rebate up to and including its stockpiling the material at Klein Point. Does the exclusion of limestone disentitle it? In view of the findings that I have already made, I do not consider that it does. I have found that Adelaide Brighton Cement's object in mining is not limestone. Indeed, it discards some of the limestone as suitable only for land re-examination [sic - reclamation]. Its operations I have found are for the recovery of calcite, alumina, silica and haematite. They are not for the recovery of limestone. The fact that limestone does or may contain those four minerals does not detract from this finding. The section focuses on Adelaide Brighton Cement's operations and on what those operations are for. It does not focus on whether the minerals sought by Adelaide Brighton Cement are found in limestone and disentitle the company to a diesel fuel claim on that basis.' 147 It seems to me to be plain from that process of reasoning of the Tribunal that the Tribunal was of the view that its conclusion that what the respondent was seeking to use in its cement processing, was the calcite, silica, alumina and haematite contained within the limestone material necessarily meant that the respondent was not mining for 'limestone'. 148 It is not surprising that the AAT reached this conclusion. There is at least dicta of this Court in Goliath at 18-19 which would seem to support this approach. It was so understood by a subsequent Full Court in David Mitchell at 257. The primary Judge also seemed to understand Goliath in this way (see at pars [46]-[53]). Nevertheless, I think that the Chief Justice is correct in his analysis of Goliath in his reasons in this case. Notwithstanding the comments in Goliath at 18-19, the actual decision in that case was that where limestone was mined in circumstances similar to those in this case then, as a matter of legal construction, the relevant mineral was 'limestone'. On this basis it seems to me that there is an inconsistency between the actual decision of the Full Court in Goliath and the decision of the Full Court in David Mitchell, notwithstanding that the Court in David Mitchell plainly thought it was applying Goliath. Given that inconsistency this Full Court, comprised as it is of 5 Judges, is free to consider the matter afresh and from first principles. 149 In that context it seems to me that the assumption made by the Tribunal that each mineral is mutually exclusive is erroneous and that the error, relating as it does to the meaning of the statute, is one of law. The assumption involves an error in interpretation that because a thing has a particular name it must be different from something with a different name. The identification of an appropriate name is thus viewed as a conclusion as to its nature and character. 150 There is no doubt that the respondent was mining limestone, or more accurately, this particular limestone, because of its inherent qualities. It was mining this limestone because it contained the four minerals that the respondent needed to make cement. The most significant of these minerals was 'calcite'. 'Calcite' in its ordinary dictionary meaning refers to 'one of the commonest minerals, calcium carbonate, occurring in a great variety of crystalline forms; calspar, limestone, marble and chalk consist largely of calcite'. Not all limestone contains calcite. Not all calcite comes from limestone. Nevertheless, some limestone is limestone only because it is a rock of a particular form which contains calcite. Given the definitions of 'limestone' and 'calcite' it is clear enough that they overlap. 151 The respondent says that there is no such overlap - there is a factual finding that the purpose was to mine calcite and that is the end of it. But that would only be true if the assumption made by the AAT was true - that calcite and limestone are mutually exclusive categories of minerals. The respondent says that whenever the product the miner seeks to recover is not limestone 'as such' (meaning unadulterated limestone used in its raw state for that purpose), but rather its constituent elements (such as calcite) then it is not 'limestone'. The only example given where such unadulterated limestone might be used was in road making or where the limestone is used directly as a building material (in South Australia, for example, limestone known as 'Mount Gambier stone' has been used in building houses). The consequence of treating calcite and limestone as mutually inconsistent categories is that the exclusion of 'limestone' from the definition of minerals effectively has no, or at least very limited content. 152 In my view 'calcite' and 'limestone' are not mutually exclusive minerals. The same thing may properly be described as both calcite and limestone. This is the issue that was raised and considered by Heerey J in Chief Executive Officer of Customs v Goliath Portland Cement Co Ltd (1999) 29 AAR 182 ('Goliath 2') at 186: 'If "limestone" has been expressly excluded from the statutory definition of "minerals" it seems to me to follow inexorably that the essential and defining component of limestone, namely calcite, must also be excluded. One cannot mine for calcite without mining for limestone, and vice versa. Goliath´s argument requires treating the exclusion as if it read "(other than agricultural use limestone or limestone where what is sought is not the limestone as such, but a mineral that is found in the limestone)".' 153 In that case His Honour concluded that calcite and limestone were invariably the same thing. I do not think that that approach is correct either. However, it is not necessary to accept the correctness of his Honour's approach in order to acknowledge that Heerey J has identified a real issue requiring an answer. 154 The respondent refers to some extrinsic material which, the respondent says, supports the interpretation for which it contends, namely that calcite is to be treated as separate from 'limestone'. As the reasons of the Chief Justice show, if the extrinsic material is to be relied upon it may suggest a different result from that contended for by the respondent. However, for my part I think that the mischief is clear enough. I do not think that the word 'limestone' is ambiguous, notwithstanding the difficulties there may be in a particular case in determining whether a particular mineral should be characterised as 'limestone' or not. Nor did the parties allege that the word was ambiguous - they agreed that it bore its usual and normal meaning. 155 However, the fact is that the AAT did not read the word 'limestone' in its usual and normal meaning. Instead it read the word 'limestone' as meaning 'limestone other than limestone where the purpose of its extraction is the constituent minerals contained within it'. This is what the respondent means when it says that the word 'limestone' means 'limestone as such'. This interpretation of the word 'limestone' is necessarily inconsistent with the approach that the word 'limestone' is to be understood in its usual and ordinary meaning. 156 Furthermore, the interpretation proposed by the respondent causes a number of logical difficulties with other aspects of the definition of 'minerals'. First, the definition expressly refers to 'agricultural limestone'. It would appear that this refers to limestone applied to the soil so as to react with it for the improvement of soil quality. If so it is the calcium carbonate within the limestone, rather than the limestone 'as such', which is the active ingredient. When that calcium carbonate is in the form of calcite then, on the approach put forward by the respondent, the agricultural limestone would be characterised as 'calcite'. Mr De Wijn QC, who appeared for the respondent, accepted that the interpretation he proposed meant that the qualification for 'agricultural limestone' was unnecessary because the relevant product recovered was not limestone. As Heerey J pointed out in Goliath 2 at 186 the same issue arises in relation to the exclusion of bentonite and kaolin from the exclusion of clay in par (a) of the definition of 'mineral' (contrast Goliath at 18-19). On the other hand, if the word 'limestone' used in the definition is interpreted in its normal and ordinary meaning then 'agricultural limestone' remains limestone (or at least it may do so) even if the active part of it that is intended to be used is calcite. 157 On the other hand, the appellant argues that if the relevant minerals (in this case calcite and the other three minerals) are not separated from the mineral containing it (in this case limestone) then, as a matter of law, it is the mineral containing it which is being mined, not those which are contained within it. It proposes what is in effect a mechanical test based upon whether or not there has been a physical separation of the relevant minerals from that mineral in which they were derived. The problem with this test is that it ignores the significance of the subjective purpose of the miner which has been referred to above. Of course, the separation of the mineral may provide factual evidence of what that relevant subjective purpose is. For example, if iron was smelted from haematite, this would provide evidence that at least subsequent to the smelting operation the subjective purpose was to obtain iron, not haematite. But this does not necessarily determine the question of what the relevant subjective purpose was prior to the smelting, or even what it was if the smelting had never occurred. 158 The haematite example seems to me to be useful in suggesting what the correct approach to characterisation must be. If haematite were excluded from 'minerals' in the same way that 'limestone' currently is, would it be an answer for a miner to say that it was not mining haematite 'as such' but was mining haematite for the purpose of extracting iron with the consequence that the qualification did not apply? It seems to me that the answer would almost certainly be 'no'. It would usually be implicit in the purpose of mining for haematite that the ultimate purpose was to extract iron. The exclusion of haematite would be rendered entirely ineffective by attempting to distinguish between haematite and iron, even if haematite, in its 'raw' state did have some separate uses. The answer, its seems to me, is to be found in the identification already made that the relevant words should bear their usual and normal meaning. Once that is accepted then the relevant question to be asked is whether on the facts as fully found in the particular case the subjective purpose of the claimant is characterised in ordinary language as the extraction of 'haematite' or some other mineral. Where the haematite was being mined for the purpose of smelting iron then the answer would be yes. Where it is being mined for the purpose of extracting (say) diamonds that were thought to be within it (or where that is a purpose of sufficient significance) the answer would probably be 'no'. 159 Similarly, in this case, the question the AAT was required to determine was whether on the facts as fully found the subjective purpose of the respondent should be characterised in ordinary parlance as the extraction of 'limestone' or some other mineral. In this case there is no doubt what the respondent's subjective purpose was. It was to carry out the mining operation already described to extract the product derived from that operation so as to use that product in the manufacture of cement. The issue in this case is not what the purpose was, but how 'the product' should be characterised for the purpose of the statutory definition of 'mining operations'. More particularly, the question in this case was whether the material in the stockpile, being the material that the respondent intended to produce, was properly described in ordinary language as 'limestone' or as some other mineral or minerals or as including some other mineral or minerals. In my view the AAT did not ask itself this question. Its failure to do so was an error of law. 160 Although the error made by the AAT was an error of law, the correct answer to the question that the AAT was required to determine also involved the determination of a question of fact: see Agfa-Gevaert at 394-396 contrast Goliath at 19 [30]. 161 If the only specific mineral within the stockpiled material that was required by the respondent was calcite then the answer to the factual inquiry that the AAT was required to undertake would seem to be obvious, even though it is a question of fact for the AAT. The answer would seem to be that which the respondent itself gave. It described the product of its mining operations as 'limestone'. It described the process of cement making as involving the use of 'limestone'. What evidence there was suggested that everyone else did the same. This is not surprising. The ultimate product was cement. The Macquarie Dictionary relevantly defines cement as a material 'commonly made by burning a mixture of clay and limestone'. That is the common understanding. It is reflected in the discussions and reasoning in cases such as North Australian Cement (No 1) and North Australian Cement (No 2). It is specifically discussed by Heerey J in Goliath 2 at 187 in a manner which seems to me to be both correct and unanswerable. The common and usual understanding is that 'limestone' is the mineral used in cement production - this is entirely consistent with the evidence before the AAT as to what the respondent called the product it produced. The fact that it was the calcite comprised in limestone that was the 'real' mineral used in making cement is not an answer - that mineral when in this particular form is normally and usually described as 'limestone' and falls within par (b) of the definition of 'mineral' in the Act. 162 That factual inquiry may be more difficult where, as here, the respondent makes use of four minerals that are contained within the particular 'limestone' and not just calcite. As a matter of fact it may be that all of the four minerals identified in the AAT reasons, in the form in which they were stockpiled, would also ordinarily or usually be described as 'limestone'. 'Limestone' is not solely comprised of calcium carbonate. It might well comprise other substances, including other minerals. Obviously it did in this case. The respondent described the product produced and stockpiled by it as 'limestone' even though it comprised not just calcite, but also the other three minerals. On the view which I have taken of the meaning of the relevant provisions of the Act, the question for the AAT remains the same: was the product extracted by the respondent 'limestone' as usually and ordinarily understood or was it limestone plus some other minerals. In my view the answer to that question is not necessarily answered merely by identifying minerals other than calcite which are used by the respondent in making cement. The product containing those other minerals could still be described as 'limestone'. 163 On the other hand, it is at least possible that the respondent's subjective purpose in using the three minerals other than calcite may have the factual result that the product in the stockpile was not only limestone as normally and usually understood, but instead or in addition one or other of the other minerals that were important to cement production. Factors such as the relative value of the mineral, its ready availability, its relative importance, whether it is usually found in limestone and so on, may well prove important in the factual inquiry of whether the product in the stockpile is only 'cement grade limestone' or that plus some other mineral. 164 Given the error in interpretation referred to above, in my view this factual issue was not explored before or by the AAT. As the AAT has still to make the relevant factual determinations based upon the understanding of the Act as discussed above, it is necessary for the case to be remitted to the AAT for further consideration of whether the material in the stockpile would be described in ordinary and usual language as 'limestone' or as 'limestone' plus one or more other minerals. 165 In my view the appeal should be allowed. I would order that the decisions of the primary Judge given on 5 August 2003 and of the AAT given on 14 August, 2002 should be set aside and that the matter be remitted to the AAT for further consideration. I would also order that the respondent pay the appellant's costs of the proceedings in this Court. I certify that the preceding thirty-seven (37) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Selway.

Associate: Dated: 7 July 2004 Counsel for the Appellant: A Robertson SC with NJ Williams SC and A Gelbart

Solicitor for the Appellant: Australian Government Solicitor

Counsel for the Respondent: J De Wijn QC with W Harris

Solicitor for the Respondent: Johnson Winter & Slattery