Works approvals
It depends on whether any part of the operation is a prescribed premises, and that is a question about categories and thresholds rather than about scale or intent. Schedule 1 of the Environmental Protection Regulations 1987 lists the categories, each with a production or design capacity at which the premises becomes prescribed. Ore processing and mine dewatering are both on that list, and both are set at 50 000 tonnes or more per year. Where a category applies, Part V of the Environmental Protection Act 1986 requires a works approval before the works are carried out, and a licence before an emission or discharge is caused. Those are two instruments answering two questions. The works approval asks what is being built. The licence asks what comes out of it once it runs. The first is the one that asks for drawings.
A works approval is a construction approval, and the Act frames it as an offence provision
Section 52 of the Environmental Protection Act 1986 is short and it is worth reading in the order it is written. An occupier of premises who carries out any work on or in relation to the premises which causes the premises to become, or to become capable of being, prescribed premises commits an offence unless the work is done in accordance with a works approval.
Two things follow from that construction. The obligation attaches to carrying out the work, not to operating afterwards — so the relevant date is the day earthmoving starts, not the day the plant is commissioned. And the phrase is or to become capable of being. Premises can be caught by building the capacity, without ever running at it.
Section 53 covers the parallel case for premises that are already prescribed: altering the method of operation, constructing or altering equipment for the handling or treatment of waste prior to discharge, or altering the materials used, where doing so may cause an emission or alter the nature or volume of what is emitted. An expansion on an operating site is a Part V question for the same reason a greenfield build is.
Whether it applies turns on a schedule, not on a judgement call
Regulation 5 does the work in one line: the premises specified in Schedule 1 are prescribed premises for the purposes of Part V of the Act. There is no discretion in that sentence and no significance test. A site either falls inside a category and its threshold or it does not.
Two categories catch most mining operations. Category 5 is processing or beneficiation of metallic or non-metallic ore, defined as premises on which ore is crushed, ground, milled or otherwise processed, or on which tailings are reprocessed, or on which tailings or residue are discharged into a containment cell or dam. Category 6 is mine dewatering, defined as premises on which water is extracted and discharged into the environment to allow mining of ore. Both carry a production or design capacity of 50 000 tonnes or more per year.
That number is lower than most people assume, and the reason the assumption runs high is that published licences quote the capacity of the particular premises rather than the threshold of the category. A licence granted for two million tonnes a year sits in the same category as one granted for sixty thousand. The threshold is what the category is triggered at, not what any given operation was approved for.
Categories 7 and 8 sit lower again — vat or in situ leaching of metal, and mineral sands mining or processing, at 5 000 tonnes or more per year. And the categories are cumulative rather than exclusive: an operation that processes ore, dewaters a pit and runs a landfill is not choosing between three descriptions. It triggers each one it meets.
The works approval and the licence are asking different questions
Section 56 is the operating offence. The occupier of prescribed premises who causes or increases an emission, or alters the nature of what is emitted, commits an offence unless they hold a licence in respect of those premises and act in accordance with its conditions. Section 57 governs how a licence is applied for.
The two instruments are joined by one subsection that explains the whole sequence. Section 56 does not apply where the emission is caused, increased or altered as a result of anything done in accordance with a works approval, and while that works approval is in force. The works approval is what carries a site legally through construction and initial operation; the licence is what carries it afterwards. A site that has built its infrastructure and let its works approval lapse before a licence issues has fallen into the gap between them.
Premises listed in Part 2 of Schedule 1 can be registered instead of licensed, and registration displaces the section 56 offence for those premises. The mining categories are not there. For an operation caught by category 5 or category 6, the destination is a licence.
The Act asks for plans and specifications, and it means both words
Section 54 sets out what an application for a works approval has to be. Made in the form and manner approved by the CEO, accompanied by the prescribed fee, and supported by such plans, specifications and other documents and information as the CEO requires.
That third limb is the substantive difference between this application and the environmental case that preceded it. A Part IV referral is assessed on predicted outcomes against environmental factors. A works approval is assessed against a described object — dimensions, levels, capacities, materials. The question is not whether the impact is acceptable in principle. It is whether the thing on the drawing does what the applicant says it does.
It follows that a design which exists only as a volume, a footprint area or a stated intention is not yet an application. It is an input to one.
Containment infrastructure is gated separately, and more tightly
The Department of Water and Environmental Regulation names three reports that a works approval may require before a site can move on, and which ones apply is set in the conditions of the works approval itself. An Environmental Compliance Report is required on all works approvals. A Critical Containment Infrastructure Report may be required where the premises include containment infrastructure. An Environmental Commissioning Report is required at the end of environmental commissioning where commissioning is permitted.
The department is explicit that an Environmental Compliance Report is not a test of the performance of the installed works or of any emissions — it is documented confirmation that what has been installed is authorised by the works approval. The Critical Containment Infrastructure Report does something different: it exists so the department can confirm that the environmental controls on containment infrastructure are properly constructed before materials are deposited in the containment cell. The stated reasoning is the practical inability to easily rectify issues once the containment infrastructure is in use.
Both reports may require a declaration from a professional with suitable qualifications or experience, confirming that each item or component has been constructed with no material defects and that the relevant conditions have been complied with. Where that is required, it is detailed in the conditions of the works approval rather than fixed in advance. And the assessment of a Critical Containment Infrastructure Report takes time that is itself a condition — generally between 10 and 45 business days, during which no environmental commissioning or operation of that infrastructure can occur.
Commissioning tests the prediction, not the intention
Environmental commissioning is defined by the department as testing undertaken to validate actual environmental performance relative to predicted performance, as assessed by the department under the works approval. It is distinguished expressly from commissioning done for production, or to check that contractors have finished the works.
That definition is the reason the modelling matters after the approval is granted rather than only before. The predicted performance being tested is whatever was put in the application. Where the prediction was a conceptual water balance carried forward from the referral, commissioning is the point at which the concept meets a rain gauge.
Which half of a works approval is surface water work
A works approval package for mine water infrastructure spans two engineering disciplines, and it is worth being clear about where the line falls. Fill and compaction specification, liner selection and batter stability geometry are geotechnical and civil questions. Storage sizing, design storm inflow, evaporation, freeboard, spillway capacity and invert setting, diversion channel capacity, flood routing and sediment basin sizing are water questions.
This is the same division the Inland Waters factor already forces between hydrology and hydrogeology, and it has the same failure mode. The parts are individually competent and the interface is where the time is lost — because the volume is usually settled at referral stage by one party, and the geometry a year later by another, with the cleared footprint fixed in between.
The unglamorous version of getting this right is not complicated. Resolve the water numbers to a footprint before the area is drawn on a referral figure, and the works approval is a drafting exercise rather than a re-approval.