THE RESOURCE MANAGEMENT & PLANNING APPEAL TRIBUNAL; Ex parte NORTH WEST RENDERING PTY LTD

Administrative Law - Judicial review - Grounds of review - Uncertain exercise of power - Orders not capable of enforcement - Whether invalid orders could be severed - Power to give directions as to constitution of decision-making body.

Environmental Management and Pollution Control Act 1994 (Tas), s48.

Resource Management and Planning Appeal Tribunal Act 1993 (Tas), s23(6).

Winn v Director-General of National Parks & Wildlife & Ors [2001] NSWCA 17; King Gee Clothing Co Pty Ltd v The Commonwealth [1945] HCA 23; (1945) 71 CLR 184, referred to.

Administrative Law - Judicial review - Grounds of review - Failure to observe statutory procedure -Amendments made when functus officio.

Resource Management and Planning Appeal Tribunal Act 1993 (Tas), s23(6).

Jayasinghe v Minister for Immigration and Ethnic Affairs [1997] FCA 551; (1997) 145 ALR 532; R v Moodie; Ex parte Mithen (1977) 17 ALR 219 at 225; Sloane v Minister for Immigration, Local Government and Ethnic Affairs [1992] FCA 414; (1992) 37 FCR 429, referred to.

Judgment Number: [2005] TASSC 8

THE QUEEN v THE RESOURCE MANAGEMENT & PLANNING APPEAL TRIBUNAL; EX PARTE NORTH WEST RENDERING PTY LTD

1 North West Rendering Pty Ltd ("North West") conducts an abattoir by-products rendering works at Quoiba, a suburb of Devonport. The operation of the works has been the subject of a number of hearings before the Resource Management and Planning Appeal Tribunal ("the Tribunal"). Three decisions of the Tribunal are the subject of these proceedings. Decision J168/2000 dated 27 October 2000 ("the first decision") relates to an application made by the Quoiba Progress Association Inc ("the Association") for an order that North West cease operating the rendering works and related orders. In support of its application, the Association relied on numerous alleged contraventions of applicable requirements by North West. Many of the alleged contraventions related to the release of offensive odours from the works. In its first decision, the Tribunal found that: there had been frequent, on average several times a week, emissions of an offensive odour from the works up to the time of the hearing before the Tribunal; the principal cause of the escape of offensive odours from the works to the nearby area was a poorly operating biofilter; and other sources of odour emissions were escape points in the works building including holes, unsealed areas and open doors. The Tribunal accepted that North West had carried out a number of substantial projects to improve the environmental performance of the works and that over the years there had been a reduction in the frequency of odour escapes and the intensity of the odour. Nevertheless, the Tribunal found that the emission of odours from the works was continuing at an unacceptably high and frequent level.

2 During the course of the hearing before the Tribunal which concluded with the first decision, North West underwent an environmental audit and obtained advice on the reduction of the emission of odours from the works. Consistent with the recommendations made, North West commenced the construction and operation of a replacement biofilter and implemented work practice changes. In its first decision, the Tribunal concluded that there was a reasonable prospect that the installation of the new biofilter, coupled with the new work practices, would reduce odour emissions from the works to an acceptable level. The Tribunal found that various aspects of North West's conduct contravened the provisions of the Environmental Management and Pollution Control Act 1994 ("EMPCA"), ss51(2) and 53(2). No challenge has been made to the appropriateness of these findings. The Tribunal noted that in consequence of these contraventions, it had jurisdiction to make orders under EMPCA, s48, which relevantly provides:

(a) a person has engaged, is engaging or is proposing to engage in conduct in contravention of this Act; or

(c) a person has caused environmental harm by contravention of this Act, any other Act or the repealed Act -

the Director, a council or a person who has, in the opinion of the Appeal Tribunal, a proper interest in the subject matter may apply to the Appeal Tribunal for an order under this section.

(2) The application may be made ex parte and, if the Appeal Tribunal is satisfied that there are sufficient grounds, it must issue a summons requiring the respondent to appear before the Appeal Tribunal to show cause why an order should not be made under this section.

(b) any other person who has, in the opinion of the Appeal Tribunal, a proper interest in the subject matter of the proceedings and desires to be heard in the proceedings -

the Appeal Tribunal may, if it considers it appropriate to do so, by order do any of the things specified in subsection (5).

(5) The Appeal Tribunal may do all or any of the following:

(a) require the respondent to refrain, either temporarily or permanently, from the act or course of action that constitutes the contravention of, the potential contravention of, or the failure to comply with, this Act;

(b) preclude, for a period specified by the Appeal Tribunal, the respondent from carrying out any use or development in relation to the land in respect of which the contravention relates;

(c) require the respondent to make good the contravention or default in a manner, and within a period, specified by the Appeal Tribunal;

(d) require compliance with any environmental agreement, environmental improvement programme or environment protection notice;

(6) If in proceedings under this section the Appeal Tribunal is satisfied that, in order to preserve the rights or interests of parties to the proceedings or for any other reason, it is desirable to make a temporary order under this section, the Appeal Tribunal may at any time during those proceedings make such an order.

(a) may be made on an ex parte application before a summons has been issued under subsection (2); and

(b) may be made subject to such conditions as the Appeal Tribunal thinks fit; and

(c) is not to operate after the proceedings in which it is made are finally determined.

(8) A person must not contravene an order or a temporary order under this section.

(9) Where the Appeal Tribunal makes an order under subsection (5)(c) and the respondent fails to comply with the order within the period specified by the Appeal Tribunal, the Director may, by leave of the Appeal Tribunal, cause any work contemplated by the order to be carried out, and may recover the costs of that work, as a debt, from the respondent.

(10) The Appeal Tribunal may, if it thinks fit, adjourn proceedings under this section in order to permit the respondent to make an application for a permit that should have been but was not made, or to remedy any other default.

(12) For the purposes of the Resource Management and Planning Appeal Tribunal Act 1993, an application under this section is deemed to be an appeal.

3 With reference to the orders it went on to make against North West, referred to in the first decision as the respondent, the Tribunal said:

"53 The evidence satisfies the Tribunal that the nature frequency and extent of the odours from the rendering works, are an unreasonable impost upon the local residents. In reaching that conclusion the Tribunal has regard, inter alia, to the character of the area including the conjunction of industrial and residential uses; the planning zoning of the area which includes residential areas in close proximity to industrial areas, and the evidence as to the nature and extent of the impact.

54 The question of whether any and if so what orders are appropriate must have regard not only to the reasonableness of the impact as it affects the residents, but also to the position of the respondent. ... "

4 The Tribunal found that in addition to the rendering works, North West owned and operated the Devonport City Abattoir and other operations, all of which were financially inter-connected and that if the rendering works were forced to close, then so might the other operations conducted by North West. The Tribunal continued:

"55 ... If the rendering plant was forced to close the consequences would include not only the employees of the rendering plant being dismissed, but also uneconomic operation and potential closure of other corporate entities operated by the respondent.

56 Further, in that context the investment of approximately $500,00.00 to date, in an endeavour to attain compliance with the required environmental standards, is a significant investment sum. The respondent does have the capacity, by borrowing or otherwise, to raise the sum necessary to carry out the recommendations made by the environmental audit consultants. ...

57 While on the one hand the respondent has made the expenditure stated above in order to attain compliance with required emission levels, the respondent has also on the evidence of the residents and Departmental officers failed to comply with environment protection notices, on occasion been less than forthcoming with information required by Departmental officers, and so doing has caused substantial impairment of the enjoyment of life by many if not most of the local residents. The Tribunal considers that the most important matters are on the one hand the protection of the residents and the environment, and on the other hand the continuance of an operation which is performing a useful function and also employing a substantial number of persons. ...

58 The Environmental Audit made a number of recommendations, in order to achieve satisfactory emission levels. Principal amongst those measures were the construction of a new biofilter, and extension of the plant building to contain some processers. There were numerous others, both for construction works or operating practices and supervision. Not all of the recommendations were regarded as practicable by the operators and/or by the Departmental officers, and some required modification. Insufficient evidence was provided to the Tribunal to enable each step required to be stated with certainty and precision. In those circumstances it is inappropriate to make specific prescriptions as to actual works or methods, including operating hours or types of machinery. These matters are best left flexible, to be the subject of consultation by the operators with, and controlled by, the Departmental officers. The Tribunal considers that it is more appropriate to state the end result which must be achieved for satisfactory operation. That is, emissions of odour must not exceed 2 odour units at the boundary of any nearby residence.

59 The Tribunal considers that the present situation cannot be allowed to continue. The respondent should however have the opportunity to achieve a level of emissions which does not unreasonably impact upon the residential areas. The period of time which the respondent sought was 3 years. In the Tribunal's view that period is on the balance of all factors, excessive, and a reasonable period is 1 year. If the rendering plant cannot achieve acceptable emission levels by the end of 1 year, then it cannot be allowed to continue.

60 Upon application A 30/00 [this is a typographical error and the reference should be A 30/99] the order of the Tribunal is that the respondent permanently cease operating the rendering plant, at the end of 18 months from the date of this decision, unless during the 13th and 14th months after this decision the emissions from the rendering works, as tested at the nearest residential boundary on 7 separate occasions, each at a different hour and on a different day of the week, while the plant is operating, do not exceed 2 odour units.

61 The testing is to be paid for by the respondent and carried out by EML Air Pty Ltd or failing that body, an equivalent body approved by the Director of Environmental Management, the testing is to be on occasions which are not made known to the respondent in advance of any test.

62 The Tribunal will entertain any application for an order for costs in application A 30/99 if made to the Tribunal in writing with supporting submissions within the next fourteen days. If requested the Tribunal will reconvene to hear any evidence in respect of any matter bearing on an order for costs of application A 30/99.

64 In the absence of any such application for an order for costs the order of the Tribunal is that each party bear its own costs."

5 The validity of the order of the Tribunal contained in pars60 and 61 of the first decision is challenged in these proceedings. However, these proceedings were not instituted until 26 August 2003 and prior to that date, there had been further proceedings before the Tribunal referable to the first decision.

6 Pursuant to par61 of the first decision, EML Air Pty Ltd ("EML") was to carry out the tests detailed in par60 of that decision. By letter dated 2 November 2000, North West's then solicitor wrote to Mr Harry Braun of EML in the following terms:

"I refer to my telephone conversation with Mr Braun on 1/11/2000 and enclose a copy of the RMAPA Tribunal decision in this matter dated 27/10/2000. I draw your attention to paragraphs 58, 59, 60 and 61 on pages 15 and 16 of the enclosed decision.

Accordingly, I would appreciate your advice as to the following:

1 Given the terms of my said telephone conversation with you whether it is possible to literally comply with the Tribunal's Order. That is to measure 2 odour units at the nearest residential boundary or whether it is only possible to measure the odour at the source and then to projections.

2 If the latter is the only feasible means of measuring odour, whether it would give effect to the intention of the Tribunal's Order.

3 Any other comments you have given the enclosed Decision and the above requests.

If it is sought to vary the Tribunal's Order, then I will tender a copy of your response, in support of that application."

7 The response from EML dated 21 November 2000 included the following:

"We advise that the odour testing procedure is not able to measure odour levels below 10 odour units so that the requirements of the determination are thus not strictly possible.

The restriction of two odour units at the nearest residential boundary can be determined instead by measurement of odour at the source (the biofilters) and then modelled using the Ausplume dispersion model to determine the predicted ground level at any location beyond the source including all possible residential receptors.

The Ausplume modelling accounts for all possible meteorological conditions and not just for the particular conditions of the day.

As the testing is to be performed on a random basis on just seven occasions these occasions may in fact occur on days of favourable dispersion characteristics. Modelling takes into account all weather conditions including the worst for dispersion."

8 By letter dated 23 November 2000, North West's then solicitor wrote to the Tribunal enclosing the abovementioned correspondence, saying:

"As can be seen from the enclosed correspondence one of two things is necessary:

(a) That the Tribunal agree that the measurements as set out in the enclosed letter from EML Air satisfy the original Order of the Tribunal in that ...

'The restriction of two odour units at the nearest residential boundary can be determined instead by measurement of odour at the source (the biofilters) and then modelled using the Ausplume dispersion model to determine the predicted ground level at any location beyond the source including all possible residential receptors.'

This was obviously the method used by EML to obtain the original odour assessments annexed to Mr Taylor's report.

(b) That the Tribunal reconvene for the purpose of hearing submissions as to the above."

9 Following a failed attempt by North West and the Association to agree on a revised form for pars60 and 61 of the first decision, the Tribunal heard North West's application to amend these paragraphs in April 2001 ("the amendment hearing"). At the outset of the hearing, North West's then counsel, in substance, said that his client accepted that the Tribunal had correctly identified the emission of odour as the nub of the problem that required attention, but that difficulties had arisen in relation to the wording of pars60 and 61 of the decision. In the course of the hearing, a number of ambiguities were canvassed in relation to those paragraphs, one ambiguity being the means by which odours emitted from the works were to be tested. It is apparent from the transcript of the amended hearing that in the course of the first hearing, the Tribunal had received a considerable quantity of evidence in relation to odours and the means of measuring the same. That evidence included the following extract taken from an environmental audit that was put into evidence:

8.1.1 The detection of an odour is an olfactory response or sensation ie neurons responding to an external stimuli (18). As odour is a sensation, variation occurs between people in not only the detection of odours but the perception of pleasantness/unpleasantness as well.

8.1.2 The measurement of odour is difficult due to the variation of responses between people. Exact scientific measurement is difficult. Odours are measured objectively using a panel of people. People who are selected for panels are chosen for their ability to detect odours but those who have sensitive noses are not included.

8.1.3 The measurement of odours is achieved through a process called 'dynamic olfactometry': In a laboratory, air samples are diluted to known levels and are presented to the panel. The panel members are in separate cubicles and the mixture is delivered via inert tubing to an outlet in the cubicle.

8.1.4 Panel members smell the mixture and indicate whether they can detect the odour. The odour threshold is determined by the level at which 50% of the panel can detect the presence of an odour. The number of dilutions required to reach the threshold is expressed in odour units (ou or OU). Therefore, one odour unit is the lowest level at which an odour can be detected by 50% of the population. Dynamic olfactometry has been developed to the stage where results are repeatable, with little variation between panels.

8.1.5 Individual odour perception is influenced by:

* Adaptation: fatigue from continued exposure to an odour in [sic] known as adaptation and is a function of the duration and intensity of the odour.

* Anosmia is the inability to detect some groups of odours.

* Age: as people age, their ability to identify odours is reduced. Persons of 18 years have been found to have 200% better sensitivity to odour than a 40 year old, and a 40 year has a 200% better perception than a 62 year old (16).

* Other factors including smoking, health, cultural and educational background etc.

8.2.1 When odour is emitted from a source, odour will be dispersed by the meteorological conditions. Windy conditions disperse and dilute the odour. This results in odour being less likely to be detected away from the source, except for periodic detection downwind. In certain other conditions, such as cold, still nights, odour is not diluted and is likely to be detectable down wind.

8.2.2 Ausplume is an air dispersion model that predicts downwind odour concentrations. The odour modelling conducted for the audit used odour emission data that was collected onsite at Quoiba, and a meteorological file representative of Quoiba (ie measurements are from a nearby site).

8.2.3 The model predicted odour levels at nearby (residences) in two situations:

2 Improved conditions resulting from the recommendations of this report.

8.2.4 The odour modelling report by EML Air Pty Ltd indicates an odour level between 2 ou and 5 ou at the nearest residences under current practices, and between 1 ou and 2 ou with the recommended changes.

8.2.5 Most people find odours offensive above 4 ou. This study predicted levels of odour that would justify complaint for residents close to the rendering plant. High numbers of complaints have been received from some complainants where the model predicts little or no odour incidents. This is most notable around Formby Grove Rd and Merseyside St and along portions of Devonport Road."

10 In the course of the amendment hearing, a person selected for a panel as canvassed in the above extract was variously described as a "registered nose", an "experienced nose" or an "independent nose". Counsel for North West before the Tribunal began the amendment hearing by contending that in the first hearing the Tribunal had proceeded on the basis that a method of modelling, described as stack modelling, was appropriate for the purposes of odour testing. However, counsel submitted that in the light of further expert evidence, a method of modelling, described as area modelling, should be adopted. Counsel later resiled from pressing for any form of modelling to be specified in the order and moved to the position that what was required was testing at the boundary by an experienced nose. In the end, counsel submitted that all that needed to be done to pars60 and 61 to make them enforceable and understandable was to clarify the meaning of "nearest residential boundary".

11 With reference to difficulties in relation to the term "nearest residential boundary", counsel for North West informed the Tribunal that there were a number of houses around the works and the two closest, in Turners Lane, were well back from their boundaries. He told the Tribunal that the blocks on which these houses were situated were much larger than a normal residential block and that there was a trotting track on one of them. As to a property at 14 Turners Lane occupied by T J and D R O'Halloran, counsel said that the nearest point of the house on that property to the works boundary was 87 metres, but that the boundary of that property was 15 metres from the works boundary. Counsel submitted that the nearest residential boundary of that property should be interpreted as being the boundary of that portion of the property specifically set aside for a residence.

12 At the conclusion of the amendment hearing, it was unclear what changes counsel for North West was advocating should be made to the Tribunal's order. The hearing finished on the basis that North West would give notice of the amendment it proposed to those who might be affected by it. Subsequent to the hearing the solicitor for North West wrote to the Tribunal advising that Mr and Mrs T J and D R O'Halloran and Mr M C Poke (the occupier of the other residence in Turners Lane that had been mentioned) did not oppose the amendment of par60, which should be varied to read:

"Upon Application A30/00 the Order of the Tribunal is that the Respondent permanently cease operating the rendering plant, at the end of 18 months from the date of this decision, unless during the 13th and 14th month after this decision the emissions from the rendering works, as tested:

(a) At the nearest residential boundary of properties zoned residential or semi residential; and

(b) At a distance of 50 metres, towards the plant, from T J & D R O'Hallorans' house at 14 Turners Lane, Quoiba,

on seven separate occasions, each at a different hour and on a different day of the week, while the plant is operating, do not exceed 2 odour units"

13 After receiving the above letter, on 1 June 2001 the Tribunal re-published decision 168/2000 incorporating the above requested amendment in substitution for par60 and adding par65, as follows:

"65 The Tribunal adjourns to a date to be fixed the determination of any issue arising as to the adequacy and results of testing referred to in paragraphs 60 and 61."

The re-published decision ("the amended decision") was endorsed:

Amended by the Tribunal pursuant to Section 22 of the Resource Management and Planning Appeal Tribunal

14 In November and December 2001, EML carried out tests pursuant to par61 of the amended decision for the purposes of establishing whether North West had complied with par60. North West and the Association disputed whether the test results showed that North West had satisfied par60 and the Tribunal conducted a hearing with a view to resolving this dispute. At the same time, the Tribunal heard an application by North West against an Environmental Protection Notice that restricted its hours of operation. In the course of its decision on the latter appeal, J62/2002, the Tribunal found that North West had not satisfied the requirements of par60 of the amended decision.

15 Following the above finding, the Association advised North West that if it did not cease operating the works, proceedings would be taken to oblige it to do so. That advice prompted North West to bring the proceedings that are now before this Court in which:

(a) Paragraphs 60 and 61 in the first decision are challenged on the basis that:

"· The Tribunal did not have jurisdiction under s48(5) of the Environmental Management & Pollution Control Act 1994 ('EMPCA') to make a prospective order in the form that it purported to make.

* The purported order is incapable of enforcement due to its uncertain and ambiguous terms."

(b) The amended decision is challenged on the basis that:

"· The Tribunal was functus officio and therefore had no power to amend its decision of 27 October 2000.

* In the alternative, against the event that the Tribunal had power to amend its order, the Tribunal did not have jurisdiction under s48(5) of EMPCA to make a prospective order in the form that it purported to make.

* Further, and in the alternative if the Tribunal had power to make the prospective order the order is incapable of enforcement due to its uncertain and ambiguous terms."

(c) The finding in J62/2002 that North West was operating in contravention of pars60 and 61 of the amended decision is challenged on the basis that the finding can have no standing as those paragraphs are beyond power.

16 Bearing in mind the role played by North West in bringing about the amendments made to the first decision, it must be said that it is incongruous for North West to now dispute their validity. Notwithstanding the apparent duplicity of North West's position, this has no bearing on the Tribunal's jurisdiction. The scope of the Tribunal's jurisdiction is circumscribed by the legislative provisions that confer it. A party's consent or acquiescence cannot enlarge the jurisdiction of a statutory tribunal.

17 Counsel for North West before this Court contends that the Tribunal had no power to amend its first decision as it was functus officio. The term "functus officio" describes a consequence of the performance of a function by an authorised entity having regard to the statutory power or obligation to perform that function. The consequence is that once the statutory function is performed, there is no further function or act for the entity authorised under the statute to carry out: Jayasinghe v Minister for Immigration and Ethnic Affairs [1997] FCA 551; (1997) 145 ALR 532 at 542, R v Moodie; Ex parte Mithen (1977) 17 ALR 219 at 225; Sloane v Minister for Immigration, Local Government and Ethnic Affairs [1992] FCA 414; (1992) 37 FCR 429. As this consequence is well settled, legislation conferring a power to act or make decisions commonly contains provisions that modify or reduce the impact of the consequence. In this instance, the applicable legislation contains some provisions that have that effect.

18 By reason of EMPCA, s48(12), the Associations's application against North West is deemed to be an appeal for the purposes of the Resource Management and Planning Appeal Tribunal Act 1993 ("RMPAT"). Pursuant to that Act: the Tribunal was required to make a decision on the application in writing and notify each party of the decision as soon as practical after making it, s23(2) and (3); the decision came into effect at the expiration of 10 days after the day on which it was made, s23(4); a party could appeal to the Supreme Court against the decision within 28 days of it being made, s25(1) and (2); and unless otherwise ordered by the Supreme Court, an appeal would not affect the operation of the decision, s26(1) and (2).

19 The only conclusion that can be drawn from the applicable provisions is that the Tribunal having published its written decision in unqualified terms save as to costs, its decision came into effect 10 days thereafter and from that time the Tribunal had no further functions in relation to the matter, save as to costs or as otherwise empowered. RMPAT, s23(5) and (6), give the Tribunal limited powers in relation to the correction and amendment of a decision. Those provisions are as follows:

"(5) The Appeal Tribunal may correct a clerical mistake or an error arising from any accidental slip or omission or an evident material miscalculation of figures or an evident material mistake in the description of any person, thing or property referred to in its decision.

(6) The Appeal Tribunal may amend its decision on an appeal if it is satisfied that the amendment -

(a) does not change the effect of any condition required by the Appeal Tribunal; and

(b) will not cause an increase in detriment to any person."

The inclusion of these provisions in RMPAT is recognition that without them the Tribunal would have no power to correct or amend a decision.

20 The endorsement on the amended decision records that it is amended pursuant to RMPAT, s22. That endorsement is consistent with comments that were made in the course of the amendment hearing to the effect that a mistake in a decision could be amended under that section. The section provides as follows:

"(1) For the purpose of an appeal, the Appeal Tribunal may do all things necessary or convenient to be done for or in connection with the hearing and determination of the appeal.

(2) Where a person appeals, or purports to appeal, to the Appeal Tribunal and it appears to the Appeal Tribunal that -

(a) a failure to comply with a requirement of this Act or of another Act or law affects the appeal or purported appeal, or decision or purported decision, against which the appeal or purported appeal has been brought; and

(b) it would not be unjust or inequitable to exercise the powers conferred by this subsection -

the Appeal Tribunal may excuse the failure by ordering that, subject to such conditions as may be determined by the Appeal Tribunal, the requirement be dispensed with to the necessary extent.

(3) Where a person appeals to the Appeal Tribunal and it appears to the Appeal Tribunal that -

(a) the appeal relates to an application made by one party to the appeal to another party to the appeal; and

(b) the appeal could be resolved in a manner that is fair to all parties if certain modifications to the application were made; and

(c) it would be conducive to the expeditious administration of justice if the powers conferred by this subsection were exercised -

the Appeal Tribunal may, by order, amend the application accordingly.

(4) Subsection (2), as amended by the Resource Management and Planning Appeal Tribunal Amendment Act 2000, is taken to extend to the exercise, or purported exercise, of any power under that subsection by the Appeal Tribunal before the commencement of that Act.

(5) Subsection (4) does not disturb the effect of a decision of the Supreme Court made before the commencement of the Resource Management and Planning Appeal Tribunal Amendment Act 2000."

As nothing in this section provides any basis for the Tribunal to amend a decision, it seems that the reference to s22 as the basis for amending the first decision, was an error and the Tribunal had in mind s23. Be that as it may, I am unpersuaded that the amendments made were the correction of a clerical mistake or an error arising out of the circumstances covered by s23(5). I am also unpersuaded that the amendments are authorised by s23(6). Paragraph 60 of the first decision specified that the tests be conducted "at the nearest residential boundary". Paragraph 60 of the amended decision specified that the tests be carried out:

(a) at the nearest residential boundary of properties zoned residential or semi-residential; and

(b) at a distance of 50 metres, towards the plant, from T J and D R O'Halloran's house at 14 Turners Lane, Quoiba.

The amendments fail to satisfy the first limb of s23(6) as they change the effect of the condition by making the closure of the works dependent upon tests taken from two sites rather than one site. The second limb of s23(6) is also not satisfied as there is no basis for concluding that the changes made in relation to the site where the tests are to be taken would not cause an increase in detriment to North West.

21 I conclude that the amendments made to the first decision are beyond the Tribunal's power. This means that par60, as amended, is invalid and it follows that the Tribunal's finding in decision J62/2002 that North West had not complied with par60 as amended cannot stand. It also follows that the validity of par60 in its unamended form must be considered.

22 Counsel for North West submits that the Tribunal does not have the power to make a prospective order of the nature of that imposed, that is, a suspended or conditional order. EMPCA, s48(3) and (5) are set out in par2 of these reasons. To my mind, pars(a) and (c) of s48(5), when read together, plainly envisage that the Tribunal is empowered to make an order to the effect that if contravening conduct has not ceased within a specified period, a respondent shall permanently refrain from that conduct. A necessary incident of this power is the power to specify the means of assessing whether contravening conduct has ceased. The power to make such an order is inherent in the provisions referred to and is consistent with the role EMPCA gives the Tribunal in relation to the management of the environment and the control of pollution. I reject the contention that the Tribunal does not have the power to make what may be characterised as a suspended or conditional order.

23 A further challenge is made to pars60 and 61 in the first decision on the basis that the order thereby made is incapable of enforcement due to its uncertain and ambiguous nature. The common law has not developed a general principle that the exercise of a statutory power must be certain. An issue as to certainty must be resolved in the light of the construction of the statute under consideration and the application of that construction to the circumstances of the particular case, Winn v Director-General of National Parks & Wildlife & Ors [2001] NSWCA 17, par12. What is required is a consideration of the power that purports to have been exercised and ultimately an assessment of whether the purported exercise is beyond that power, King Gee Clothing Co Pty Ltd v The Commonwealth [1945] HCA 23; (1945) 71 CLR 184 at 195 - 196.

24 EMPCA, s48(8), provides that a person must not contravene an order made under the section and specifies a penalty for such a contravention of not exceeding 500 penalty units, that is, $50,000. Besides proceedings seeking a penalty for the contravention of an order, it may be necessary to take proceedings for an injunction against further contraventions of an order. Plainly, in these circumstances, a requirement inherent in the grant of the power to make orders that a respondent refrain from conduct is that the order must be sufficiently certain to enable the determination of whether it has been breached, Television Corporation Ltd v The Commonwealth [1963] HCA 30; (1963) 109 CLR 59 at 71.

25 It is clear from what was said in the course of the hearing that preceded the Tribunal's purported amendment of par60 that it was recognised that the order contained in pars60 and 61 of the first decision failed the test of certainty in a number of ways. However, in considering the validity of the order, I should confine my attention to the record of the Tribunal in relation to the first decision, Craig v The State of South Australia (1994 - [1995] HCA 58; 1995) 184 CLR 163. The proceedings before me are the return of a general order to show cause why a writ of certiorari or further or other relief should not be granted. Whilst, since 1 December 2001, prerogative writs including certiorari are no longer to be issued, Judicial Review Act 2000, s43, this Court still has power to grant relief of the nature of certiorati, and this power includes a power to order that a determination or order be quashed, Tasman Quest Pty Ltd v Evans; Tasman Quest Pty Ltd v Knowland [2003] TASSC 110. What transpired before the Tribunal subsequent to its first decision does not form part of its record for the purposes of this aspect of the matter before me. I will confine my attention to the first decision, and more particularly the requirement in par60 that the tests be carried out "at the nearest residential boundary". There is no indication in the decision of the point along the length of that boundary where the tests were to be undertaken and, more particularly, the paragraph does not specify what that residential boundary must be nearest to. The emissions in question come from various parts of the works on the property occupied by North West. One source given particular attention in the decision is a biofilter. It cannot be discerned from the decision whether the residential boundary referred to is a boundary nearest to: the biofilter; the boundary of the land occupied by the works; the perimeter of the works structure; or a particular structure on the works. As it is not possible to identify the residential boundary referred to or, if it could be identified, to establish where along the length of that boundary the tests were to be undertaken, it is not possible to determine whether the order contained in pars60 and 61 of the first decision has been breached. In consequence, due to uncertainty, those paragraphs are ultra vires. I note that a similar problem was dealt with in R v Fenny Stratford Justices, ex parte Watney Mann (Midlands) Ltd [1976] 2 All ER 888. In that case, the applicant brewer sought an order of certiorari to quash the portion of an order that specified that the level of noise from a brewery should not exceed 70 decibels. The court held that because the order in question did not specify where the noise level was to be recorded it was so imprecise as to be void for uncertainty.

26 The first order I make arising from these findings is that the Tribunal's amended decision J168/2000 dated 10 June 2001 be quashed and I declare that its finding in decision J62/2002 that pars60 and 61 of the amended decision have not been satisfied by North West is of no effect. With reference to the Tribunal's first decision, J168/2000 dated 27 October 2000, I have no hesitation in concluding that pars60 and 61 are a distinct and severable portion of the decision and that the balance of it, which has not been the subject of any challenge in these proceedings, should stand. Counsel for North West submits that the entire first decision should be quashed but advanced no reasons for advocating such an unwarranted outcome. It is beyond question that in proceedings of the nature of certiorari where partial invalidity is established, it is open to quash only the invalid portion of the decision or order, provided it is severable: R v Marshall & Ors; Ex parte Baranor Nominees Pty Ltd [1986] VicRp 2; [1986] VR 19; R v Hannan; Ex parte Abbott [1986] NTSC 22; (1986) 41 NTR 37; R v Fenny Stratford Justices, ex parte Watney Mann (Midlands) Ltd (supra); R v Elliott; ex parte Elliott (1974) 8 SASR 329; and Cheatley v R (1971 - [1972] HCA 63; 1972) 127 CLR 291 at 308. The situation before me is similar to that which arises in disciplinary proceedings, where a jurisdictional error in relation to penalty does not ordinarily affect the validity of an underpinning finding of misconduct, Malone v Marr (1981) 2 NSWLR 894 at 908 - 910. More generally as to severability, see Public Service Board of New South Wales v Etherton (1985) 1 NSWLR 430 and Foxtel Management Pty Ltd v Australian Competition and Consumer Commission [2000] FCA 589; (2000) 173 ALR 362. I order that pars60 and 61 of the Tribunal's first decision, J168/2000 dated 27 October 2000, be quashed and I declare that this order does not affect the validity of the balance of that decision.

27 Counsel for North West submits that I should not remit the matter to the Tribunal to conduct a hearing as to the orders, if any, that the Tribunal considers should be made in lieu of the quashed pars60 and 61. He contends that as the primary remedy sought in the general order to show cause is certiorari, the Court has no power to make such an order. I note that such an order is not necessary. When an invalid decision is quashed in whole or in part, the normal expectation is that the decision-maker will decide the matter afresh in the light of the principles of law determined in the proceedings that resulted in the quashing: R v Industrial Appeals Court; Ex parte Henry Berry & Co (Australasia) Ltd [1955] VicLawRp 29; [1955] VLR 156 at 165; Ex parte Currie; re Demsey & Ors (1970) 72 SR (NSW) 429 at 434; and Attorney-General for New South Wales v Dawes & Anor [1976] 1 NSWLR 242 at 248. In any event, the Court has the power to make the order in question. Such an order is within the scope of Supreme Court Rules 2000, r627(1) and (2), the effect of which is that upon the return of a general order, the Court may grant any form of relief that might be granted by way of a prerogative writ and may order the decision-maker to perform some lawful duty. I am also of the view that an order that the Tribunal that deals with the matter be as constituted when the first decision was made would be within the scope of the Court's power. R v Willee; Ex parte Chandler [2001] TASSC 85 is a case in which the Court exercised its power to make orders such as those under consideration. In that case, the Court had before it the return of a general order directed to a magistrate to show cause why a writ of certiorari should not be granted to quash his decision. Cox CJ found that some of the orders made by the magistrate were beyond power, quashed those orders and referred the matter back to the same magistrate with a direction that he perform such lawful duties as are necessary to make enforceable orders.

28 Whilst the cases where it is appropriate in the interests of justice to order that particular people or a particular person should constitute the entity to which a matter is referred back are small in number, Minister for Immigration and Multicultural Affairs v Wang (2003) 77 ALJR 786 [41], this is such a case. What is required of the Tribunal is the valid formulation of the orders it considers appropriate, if any, pursuant to EMPCA, s48(5), arising from its findings that North West's conduct contravened EMPCA, ss51(2) and 53(2). The situation would be otherwise if those findings had been quashed. In such a situation, for the same members to rehear the issue of whether there had been contraventions uncontaminated by their earlier conclusions on this matter would be an impossible task; Seablest Pty Ltd v Smith & Ors [1997] TASSC 36; (1997) 6 Tas R 350 at 361 and R v Resource Planning & Development Commission; ex parte Dorney & Anor (No 3) [2003] TASSC 84; (2003) 12 Tas R 147 [18]. The Tribunal's findings as to North West's contraventions have not been the subject of any challenge. There is no suggestion that the findings are contaminated by any erroneous view that the Tribunal formed on the applicable legal questions or that more findings as to the contraventions needed to be made. If this was so, the Tribunal may have needed to be differently constituted; Minister for Immigration and Multicultural Affairs v Wang (supra) [73 - 76].

29 I am informed that the Tribunal, as constituted when the first decision was made, is available to deal with the matter. Notwithstanding that I am firmly of the view that it is appropriate that the Tribunal so constituted deal with the matter, I will refrain from making an order to that effect as it is conceivable that a change of circumstances could make it inappropriate or impossible for this to occur. Having recorded my views as to this, I will simply order that the matter be remitted to the Tribunal to conduct the necessary hearing.

(1) That the Tribunal's amended decision J168/2000 dated 10 June 2001 be quashed and it is declared that its finding in decision J62/2002 that pars60 and 61 of the amended decision have not been satisfied by North West is of no effect.

(2) That pars60 and 61 of the Tribunal's first decision, J168/2000 dated 27 October 2000 be quashed and it is declared that this order does not affect the validity of the balance of that decision.

(3) That the first decision be remitted to the Tribunal to conduct a hearing as to the orders, if any, the Tribunal considers should be made in lieu of the quashed pars60 and 61.