Reporting thresholds are set out in clauses 10 to 12 of the NPI NEPM. Each NPI substance belongs to at least one category, and a facility must report a substance once it exceeds that substance’s threshold in the reporting period.
Key points
- Category 1: 10 tonnes or more of a substance used
- Category 1a: 25 tonnes of TVOC. Category 1b: 5 kilograms of mercury
- Category 2a: 400 tonnes of fuel or waste burnt, or 1 tonne in an hour
- Category 2b: 2,000 tonnes burnt, 60,000 MWh of electricity or a 20 MW rating
- Category 3: 15 tonnes of total nitrogen or 3 tonnes of total phosphorus
The six categories
| Category | What trips the threshold in the reporting period |
|---|---|
| 1 | Using 10 tonnes or more of the substance |
| 1a | Using 25 tonnes or more of total volatile organic compounds (TVOC) |
| 1b | Using 5 kilograms or more of mercury and compounds |
| 2a | Burning 400 tonnes or more of fuel or waste, or 1 tonne or more in any single hour |
| 2b | Burning 2,000 tonnes or more of fuel or waste, or consuming 60,000 megawatt hours or more of electricity, or having a maximum potential power consumption rated at 20 megawatts or more (electricity limbs exclude lighting and motive purposes) |
| 3 | Emitting to water, or transferring to a mandatory reporting transfer destination, 15 tonnes or more of total nitrogen or 3 tonnes or more of total phosphorus |
What “use” means
Use covers handling, manufacture, import, processing, coincidental production and any other use. A substance contained in an article in a way that does not lead to its emission is not counted. Substances in proprietary mixtures count where they are named on the safety data sheet, and DCCEEW advises using the midpoint where a sheet gives a range.
Points that are often missed
- If either the total nitrogen or the total phosphorus threshold is exceeded, both must be reported.
- Groundwater is excluded from the Category 3 calculation.
- Category 1 substances contained in mined ore, waste rock and overburden count towards the use threshold.
Why it matters
Thresholds are tested every reporting period. A change in production, fuel use or raw materials can bring a facility into reporting, or add new substances, even when nothing else about the site has changed. The TVOC threshold counts all volatile organic compounds together, including those not listed individually.
References & sources
Primary regulatory documents and authoritative references underpinning this answer.