PRTR Reporting for Scottish Industry
What does PRTR reporting mean for industrial sites in Scotland?
For an industrial site in Scotland, PRTR reporting means sending SEPA an annual return to the Scottish Pollutant Release Inventory (SPRI). The return covers the previous calendar year's releases of listed pollutants to air and water, plus off-site transfers of waste and waste water, and is due by 28 February each year. SPRI is Scotland's own PRTR, and it is wider than the UK PRTR: SEPA passes a subset of the SPRI data to Defra for the UK register.
Approach: I used the SEPA Scottish Pollutant Release Inventory data (2020-2024 workbooks), SEPA's SPRI and UK-PRTR web pages, SEPA's 2022 SPRI statistics report, and the gov.uk UK PRTR pages. I could not open the legislation.gov.uk text of the retained PRTR Regulation (EC) No 166/2006 or regulation 37 of the Environmental Authorisations (Scotland) Regulations 2018, so I have not quoted article wording from either.
Legal basis and who is caught
- Legal duty: SEPA's current page says sites served a "Regulation 37(1) Notice" under the Environmental Authorisations (Scotland) Regulations 2018 are legally required to complete a SPRI return every year (SEPA SPRI). SEPA's 2022 report instead names a Pollution Prevention and Control (PPC) Regulation 63(2) Notice or a notification letter. The two SEPA sources differ on which notice applies, and I could not open the regulation itself to settle it.
- Scope: sites carrying out 67 activities in 10 sectors above set capacity thresholds (SEPA 2022 report, pp. 48-49). These include:
- most Part A activities under the PPC (Scotland) Regulations 2012;
- municipal sewage works above 15,000 population equivalent;
- industrial waste-water plants treating at least 10,000 m³/day;
- all marine-caged fish farms, with no capacity limit;
- quarries and opencast mines of 25 hectares or more, and all underground mining;
- sites with a waste management licence that can accept at least 50 t/day of non-hazardous waste for disposal, or 10 t/day of hazardous waste for recovery or disposal;
- nuclear installations, including those being decommissioned.
- Sites with only a waste management licence: they report off-site waste transfers to SEPA quarterly, and SEPA uses that data to meet their SPRI obligation (p. 49).
- Idle sites: a site that did not operate must still file a return while it holds an active permit. Past reporters normally keep reporting every year.
What a return involves
- Format: SEPA emails each site a tailored form in January. The completed form goes back to SPRI.Administration@sepa.org.uk by 28 February.
- Release codes: every SPRI pollutant has a reporting threshold, and each one on the form gets a code:
- ART (above reporting threshold): you must give a value;
- BRT (below reporting threshold);
- NE (not emitted).
- Accidental releases: these count in the annual total.
- Methods: you can measure, calculate or estimate, using the best available method. Often this is the method set in your SEPA permit.
- Units and records: pollutants are reported in kg and waste in tonnes. Keep supporting records for five years in case of audit.
- Checks: SEPA rejects incomplete returns and cross-checks figures, for example CO₂ against Emissions Trading System data. The data remains the operator's legal responsibility. SEPA does not use SPRI data to judge compliance (SEPA 2022 report, pp. 49-52).
Examples of SPRI reporting thresholds (2024 data)
| Medium | Pollutant | SPRI threshold (kg/yr) | Example record |
|---|---|---|---|
| Air | Carbon dioxide | 10,000,000 | Granish landfill, BRT [1] |
| Air | Methane | 10,000 | Granish landfill, ART 38,900 kg [2] |
| Air | Nitrogen oxides (as NO₂) | 100,000 | [3] |
| Air | Ammonia | 1,000 | [4] |
| Air | Mercury | 1 | [5] |
| Water | Total nitrogen (as N) | 50,000 | [6] |
| Water | Total phosphorus (as P) | 5,000 | [7] |
| Water | Copper | 20 | [8] |
| Water | Zinc | 100 | St Molios fish farm (Arran), ART 188.66 kg [9] |
| Water | Emamectin benzoate | 0.001 | St Molios fish farm, ART 0.0531 kg [10] |
Waste transfers are recorded by type and route, for example 72,816.94 t of non-hazardous waste sent for disposal from Summerston landfill in Glasgow [11].
These are SPRI thresholds only. UK PRTR thresholds are in Annex II of the retained Regulation 166/2006, which I could not open, so I have not compared the two sets of values.
How SPRI relates to the UK PRTR
- Pollutants: SPRI covers 110 pollutants and the UK PRTR 91 (SEPA UK-PRTR page).
- Activities: SPRI uses lower thresholds for some pollutants and activities, such as sewage works and fish farms. It also adds things the UK PRTR does not cover, such as radioactive substances.
- UK PRTR trigger: a facility falls under the UK PRTR if it carries out an Annex I activity above its capacity threshold and goes over the Annex II pollutant thresholds. Off-site waste transfers count from 2 t/yr of hazardous waste or 2,000 t/yr of non-hazardous waste.
- Overlap: about half of SPRI sites go over the UK PRTR thresholds. The SPRI data passed to Defra is about 20% of reported rows but about 90% of total emissions (SEPA 2022 report, p. 52).
- Publication: the UK PRTR rests on SI 2018/1407 and implements the Kiev Protocol. Defra aims to publish each year's data about a year after it ends; 2025 data is likely by the end of 2026 (gov.uk UK PRTR).
- No separate UK filing: a Scottish operator does not file with Defra. The SPRI return to SEPA covers both registers.
Compliance in practice: in 2022, 1,287 sites were expected to report and 1,241 (96.4%) did. 213 of the returns had nothing reportable, but the sites still had to file (p. 4).
Sources:
Which sites must report to SEPA?
You must report to SEPA if your site carries out one of the 67 activities in 10 sectors on SEPA's Scottish Pollutant Release Inventory (SPRI) list above its capacity threshold, and SEPA has served you a notice. SEPA's current page says the legal duty falls on anyone who receives a "Regulation 37(1) Notice" under the Environmental Authorisations (Scotland) Regulations 2018. Once you are caught, you must file every year by 28 February for the previous calendar year.
Approach: I checked the 2024 SPRI returns to see which activities actually reported. I also read SEPA's current SPRI and activity-code pages and the scope section of SEPA's 2022 SPRI report.
What triggers the duty
- Notice: you need a Regulation 37(1) Notice (SEPA SPRI). The 2022 report instead says most reporters are notified by a PPC Regulation 63(2) Notice or a notification letter (SEPA 2022 report, p. 49). The current page is the newer of the two.
- Activity: you carry out a listed activity above its threshold. SEPA says the thresholds largely follow earlier EU reporting rules, but some are lower so that more Scottish sites are caught (p. 48).
- Idle sites: a site that has not operated and has no emissions must still file while it holds an active permit (p. 49). If you reported before, you will probably have to keep reporting every year.
- Closures: a site that closes during the year must still report for the months it operated. Your return should say whether the site was not operating or its permit was revoked.
- Sites with only a waste management licence: they report off-site waste transfers to SEPA every quarter, and SEPA uses that data to meet their SPRI obligation (p. 49).
SEPA's summary of who is in scope (2022 report, pp. 48-49)
- most Part A activities under the PPC (Scotland) Regulations 2012;
- municipal sewage works above 15,000 population equivalent;
- industrial waste-water plants that can treat at least 10,000 m³/day;
- all marine-caged fish farms, with no capacity limit;
- opencast mining and quarrying of 25 hectares or more, and all underground mining;
- sites with a waste management licence that can accept at least 50 t/day of non-hazardous waste for disposal, or 10 t/day of hazardous waste for recovery or disposal;
- all nuclear installations, including those being decommissioned, and all non-nuclear sites authorised for releases to air, water or waste water.
Activity codes and thresholds (from the SEPA activity-codes page), with an example site that reported in 2024 where one was found:
| Sector | Code: activity (threshold) | 2024 example reporter |
|---|---|---|
| Energy | 1(a) refineries (none) | Grangemouth Refinery [12] |
| 1(b) gasification/liquefaction (none) | Mersen Scotland [13] | |
| 1(c) combustion (50 MW heat input) | Peterhead Power Station [14] | |
| 1(d) coke ovens, 1(e) coal rolling mills (1 t/h), 1(f) coal products/smokeless fuel | none found | |
| Metals | 2(a) ore roasting/sintering; 2(b) pig iron/steel (2.5 t/h) | none found |
| 2(c).i hot-rolling (20 t/h) | Dalzell Steel Works [15] | |
| 2(c).ii smitheries (50 kJ per hammer; >20 MW) | Wyman Gordon, Livingston [16] | |
| 2(d) ferrous foundries (20 t/day) | Progress Rail Services [17] | |
| 2(e).i non-ferrous crude metals (none) | MAHLE Engine Systems [18] | |
| 2(e).ii non-ferrous smelting (4 t/day Pb/Cd; 20 t/day others) | Grangemouth Works [19] | |
| 2(f) surface treatment of metals/plastics (30 m³ vats) | Vector Aerospace, Almondbank [20] | |
| Minerals | 3(a) underground mining (none) | Cononish Gold & Silver Mine [21] |
| 3(b) opencast mining (25 ha) | Snabe Quarry [22] | |
| 3(c).i cement clinker (500 t/day) | Tarmac Dunbar [23] | |
| 3(e) glass (20 t/day) | Superglass, Stirling [24] | |
| 3(g) ceramics (75 t/day or 4 m³ kiln) | Blantyre Brick Plant [25] | |
| 3(c).ii-iii lime, 3(d) asbestos, 3(f) mineral fibres | none found | |
| Chemicals (industrial scale) | 4(a) organics | INEOS Grangemouth [26] |
| 4(b) inorganics | Shin-Etsu Handotai, Livingston [27] | |
| 4(d) plant health/biocides | Syngenta Grangemouth [28] | |
| 4(e) pharmaceuticals | GSK Montrose [29] | |
| 4(f) explosives | Chemring Energetics, Ardeer [30] | |
| 4(c) fertilisers | none found | |
| Waste and waste water | 5(a) hazardous waste (10 t/day) | Earls Road, Grangemouth [31] |
| 5(b) municipal incineration (3 t/h) | MVV Baldovie, Dundee [32] | |
| 5(c) non-hazardous disposal (50 t/day) | Goathill Quarry, Fife [33] | |
| 5(d) non-inert landfills (10 t/day or 25,000 t) | Bennadrove landfill, Lewis [34] | |
| 5(e) animal carcasses (10 t/day) | Dundas Chemical Co [35] | |
| 5(f).i sewage works, 15,000 to 100,000 p.e. | Forres STW [36] | |
| 5(f).ii sewage works, 100,000 p.e. | Peterhead STW [37] | |
| 5(g) independent industrial waste-water plants | Daldowie RDF Plant [38] | |
| 5(h) non-hazardous recovery (75 t/day; sub-codes i-v) | Ellon Brewery effluent plant, 5(h).v [39] | |
| Paper and wood | 6(b) paper/board/panels (20 t/day) | Chirnside Plant [40] |
| 6(c) wood preservation (50 m³/day) | Robertson Timber [41] | |
| 6(a) pulp | none found | |
| Livestock and aquaculture | 7(a).i poultry (40,000 places) | Millenium Farm, Peebles [42] |
| 7(a).ii pigs over 30 kg (2,000 places); 7(a).iii sows (750 places) | Townhead Pig Unit [43]; Penmanshiel Farm [44] | |
| 7(b).i fish farms not exceeding 1,000 t/yr | Castle Bay, Shuna [45] | |
| 7(b).ii fish farms of 1,000 t/yr | St Molios, Arran [46] | |
| Food and drink | 8(a) slaughterhouses (50 t carcass/day) | McIntosh Donald, Portlethen [47] |
| 8(b).i animal raw materials (75 t/day) | Biomar, Grangemouth [48] | |
| 8(b).ii vegetable raw materials (300 t/day) | Girvan Distillery [49] | |
| 8(c) milk (200 t/day) | The Creamery, Stranraer [50] | |
| Other | 9(a) textiles (10 t/day) | Halley Stevensons, Dundee [51] |
| 9(b) tanning (12 t/day) | Bridge of Weir Leather [52] | |
| 9(c) solvent surface treatment (150 kg/h or 200 t/yr) | Zhuorim TTR, Aberdeen [53] | |
| 9(e) shipbuilding/painting (100 m ships) | Rosyth Dockyard [54] | |
| 9(d) carbon/electrographite | none found | |
| Radioactive | 10(a) nuclear (none) | Dounreay [55] |
| 10(b) non-nuclear radioactive (none) | James Hutton Institute, Dundee [56] |
"None found" only means I found no 2024 return under that code. It does not mean the code is out of scope.
Points where SEPA's sources differ
- 5(g) industrial waste-water plants: the activity-codes page gives 10,000 m³/day with a lower 2,000 m³/day figure for Scotland. The 2022 report gives 10,000 m³/day.
- 5(f) sewage works: the activity-codes page swaps the 5(f).i and 5(f).ii labels compared with the 2024 data. In the data, 5(f).i is 15,000 to 100,000 population equivalent and 5(f).ii is 100,000 population equivalent.
- 5(h).v: the activity-codes page describes it as anaerobic digestion only, at 100 t/day. The 2024 data describes it as non-hazardous recovery above 75 t/day.
If you tell me your activity and capacity, I can match it to a code and pull that sector's past SPRI returns.
Sources:
How can I find a site's releases?
Look the site up by name in SEPA's Scottish Pollutant Release Inventory (SPRI). That gives you its NIC, SEPA's site number. Then search by the NIC to get every pollutant release and waste transfer the site reported, one row per pollutant per year, for 2020 to 2024. I can run this for any Scottish site. Here it is for St Molios fish farm on Arran.
Approach: I searched the SEPA SPRI annual data, which comes as one workbook per year, each with a Pollutants sheet and a Waste sheet.
How the lookup works
- Find the site and its NIC. Searching "St Molios" finds "St Molios MCFF, Lamlash Bay". It is NIC 989, run by Bakkafrost Scotland Limited, under activity code 7(b).ii, a fish farm producing 1,000 t/yr [46].
- Search by NIC, not name. Only the 2024 data in the results shows the site name. The 2020-2023 rows only had the NIC, so a search by name would have missed those years.
- Read each row. A row gives:
- the medium (air, water and so on);
- the pollutant;
- the total release in kg;
- the SPRI reporting threshold;
- the code: ART (above threshold), BRT (below threshold) or NE (not emitted);
- whether the figure was measured (M) or calculated (C).
- Check waste transfers separately. Off-site transfers are on the Waste sheet, recorded by waste type and route. St Molios has no Waste rows in any year, so all of its returns are releases to water.
Example: St Molios (NIC 989), releases to water, kg/yr
| Pollutant (threshold) | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|
| Total nitrogen as N (50,000) | 61,605 [57] | 47,562 [58] | 34,029 [59] | 29,174 BRT [60] | 66,818 ART [61] |
| Total phosphorus as P (5,000) | 8,507 [62] | 6,568 [63] | 4,699 [64] | 4,029 BRT [65] | 9,227 ART [66] |
| TOC or COD/3 (50,000) | 197,650 [67] | 152,594 [68] | 109,178 [69] | 93,600 ART [70] | 214,376 ART [71] |
| Zinc (100) | 173.94 [72] | 134.29 [73] | 96.08 [74] | 82.37 BRT [75] | 188.66 ART [9] |
| Copper (20) | 1,189.91 [76] | 6.42 [77] | 4.59 [78] | 3.94 BRT [79] | 9.02 BRT [80] |
| Emamectin benzoate (0.001) | 0.4533 [81] | 0.37 [82] | 0.19 [83] | 0.01 ART [84] | 0.0531 ART [10] |
| Deltamethrin (0.002) | not listed | not listed | no figure given [85] | 0, NE [86] | 0.005 ART [46] |
The site also reported three other fish-farm medicines: teflubenzuron, azamethiphos and cypermethrin.
Points to watch when reading the data
- Missing codes before 2023: the 2020-2022 rows give no ART/BRT/NE code. Compare the quantity with the threshold yourself. The 2020-2021 rows also give no unit.
- Blank quantity: a blank means the sheet records no figure for that row. It does not mean the release was zero.
- Narrowing a search: you can filter by year, by medium, by pollutant name, or by waste type and route.
If you give me a site name, operator or postcode, I can find its NIC and pull its full release and waste-transfer history.