Permit (Application) Number: PPC/A/1003157

Applicant: MVV Environment Baldovie Ltd

MVV Environment Baldovie Ltd

Baldovie EFW CHP facility

Permit Variation

PPC/A/1003157-CP01/VN05 1 NON TECHNICAL SUMMARY OF DETERMINATION .................................................................2 2 EXTERNAL CONSULTATION AND SEPA’S RESPONSE ..........................................................5 3 ADMINISTRATIVE DETERMINATIONS .......................................................................................9 4 INTRODUCTION AND BACKGROUND .......................................................................................9 4.1 Historical Background to the activity and variation .................................................................9 4.2 Description of activity ............................................................................................................... 11 4.3 Outline details of the Variation applied for .............................................................................. 11 4.4 Guidance/directions issued to SEPA by the Scottish Ministers under Reg.60 or 61. .......... 13 4.5 Identification of important and sensitive receptors ................................................................ 13 5 KEY ENVIRONMENTAL ISSUES ............................................................................................... 16 5.1 Summary of significant environmental impacts ..................................................................... 16 5.2 Implications of the Variation on - Point Sources to Air .......................................................... 18 5.3 Implications of the Variation on - Point Source Emissions to Surface Water and Sewer .... 36 5.4 Implications of the Variation on - Point Source Emissions to Groundwater ........................ 40 5.5 Implications of the Variation on - Fugitive Emissions to Air .................................................. 40 5.6 Implications of the Variation on - Fugitive Emissions to Water ............................................. 42 5.7 Implications of the Variation on - Odour ................................................................................. 43 5.8 Implications of the Variation on - Management ...................................................................... 47 5.9 Implications of the Variation on - Raw Materials .................................................................... 49 5.10 Implications of the Variation on - Raw Materials Selection .................................................... 51 5.11 Implications of the Variation on - Waste Minimisation Requirements................................... 53 5.12 Implications of the Variation on - Water Use ........................................................................... 53 5.13 Implications of the Variation on - Waste Handling ................................................................. 54 5.14 Implications of the Variation on - Waste Recovery or Disposal ............................................ 60 5.15 Implications of the Variation on - Energy ................................................................................ 60 5.16 Implications of the Variation for - Accidents and their Consequences ................................. 64 5.17 Implications of the Variation for - Noise .................................................................................. 67 5.18 Implications of the Variation for - Monitoring ......................................................................... 70 5.19 Implications of the Variation for - Closure .............................................................................. 74 5.20 Implications of the Variation for - Site Condition Report (and baseline report) ................... 74 5.21 Implications of the Variation for - Consideration of BAT ....................................................... 76 6 OTHER LEGISLATION CONSIDERED ...................................................................................... 81 7 ENVIRONMENTAL IMPACT ASSESSMENT AND COMAH ...................................................... 82 8 DETAILS OF PERMIT ................................................................................................................ 83 9 EMISSION LIMIT VALUES OR EQUIVALENT TECHNICAL PARAMETERS/ MEASURES ...... 91 10 PEER REVIEW ........................................................................................................................... 94 11 FINAL DETERMINATION ........................................................................................................... 94 12 REFERENCES AND GUIDANCE ............................................................................................... 94

1 NON TECHNICAL SUMMARY OF DETERMINATION

PPC requires that where the draft determination of an application or a SEPA initiated variation is to be subject to public consultation (this is usually referred to as PPD consultation) the decision document will contain a non technical summary of the determination. There is no need to have a non technical summary if the application is no subject to PPD Will the draft variation determination be subject to public consultation? Yes

A Variation has been received from the current Operator of the incineration plant on Forties Road, in Dundee. The Operator is MVV Environment Baldovie Limited, known as MEB. The Variation application is made for a new Moving Grate Combined Heat & Power (CHP) Energy from Waste (EFW) plant to replace the existing Fluidised bed plant, (hereafter referred to as the ‘Existing EFW Plant) which is nearing its end of life. The replacement plant will be known as the Moving Grate EFW CHP Plant (hereafter referred to as the ‘New EFW CHP Plant’), and forms part of a region-wide residual waste contract with two local authorities, Dundee City Council (DCC) and Angus Council. The new EFW plant will be constructed on a brownfield site, adjacent to and south of the existing EFW plant, close to the Michelin Tyre factory. The New EFW CHP Plant will be capable of incinerating up to 153,216 tonnes per annum, at a maximum throughput of 21.07 tonnes per hour (Te/hr), based on a Lower Calorific Value LCV of 7.5 MJ/kg, however, the throughput will typically be around 110,000 Te/hr, based on waste with an average LCV of 10.5MJ/kg, and with an annual operational availability of 8,000 hours. Due to the variability of the incoming wastes, the plant must be able to burn wastes that have a high CV also, and in such circumstances, the tonnage throughput may reduce to as little as 9,576 Te/hr. The process operational systems are set to automatically alter the throughput to ensure a consistency in the heat input. The New EFW CHP Plant has been designed to comply with the stringent requirements and the Emission Limit Values (ELVs) for waste incineration plant, in Chapter 4 and Annex VI of the Industrial Emissions Directive (IED) 2010/75/EU, which is enacted in Scotland by the Pollution Prevention and Control (Scotland) Regulations 2012 (as amended) – referred to as PPC2012.. The new EFW CHP plant will treat residual non-hazardous Municipal Solid Waste (MSW) and Commercial and Industrial Waste (C&I) of a similar nature. The wastes for incineration will have been subject to kerbside sorting or segregation at the commercial premises as required by regulation. Wastes collected from household clearances will eventually be screened in the Existing Plant following the decommissioning, and components that can be recycled will be removed. (This activity currently takes place at a transfer station to the north of the Existing Plant). All waste that cannot be recycled will be transferred to the New EFW plant for incineration. Incoming waste for incineration is delivered to site, by contained vehicles, including Refuse Collection Vehicles (RCVs) and bulk containers, and weighed at the existing weighbridge on arrival at the site. It is currently delivered into the Existing EFW Plant tipping hall prior to incineration. Once the New EFW CHP Plant is operational, the waste will arrive across the existing weighbridge, prior to delivery into the waste reception hall of that plant, and delivered via chutes into the waste storage bunker. A crane will mix the waste in the tipping area of the bunker to ensure the waste is homogenous when fed to the incinerator. This is required to reduce disturbance during combustion. The crane either feeds the waste into the storage area of the bunker or directly into feed hopper from where it drops via a feed chute onto the inclined reciprocating moving grate (the “grate”) for primary combustion. The solid waste (which is the ‘fuel’) will be combusted on the grate using primary air injected via the grate bars. The gases generated from primary combustion will pass through a four-pass vertical tube boiler at temperatures of at least 850⁰C for a minimum residence time of 2 seconds, as required by the

IED for non-hazardous waste, to ensure that organic compounds such as dioxins and furans are

destroyed. The temperature and residence time was modelled using a site specific Computational Fluid Dynamics (CFD) model, submitted following a Further Information request. Two low sulphur light fuel-oil fired ancillary automatic burners will ensure that the temperature is maintained, and this will be verified during commissioning of the New EFW CHP incinerator, including under the most unfavourable conditions. The combustion is controlled by an automated combustion control system, and if the minimum temperature is not met, automatic interlocks will prevent waste being fed onto the grate. The secondary combustion (the oxidation and burnout of any unburned gases) takes place in the flame body above the grate, and secondary air is added at this point. The gases continue around the first two empty passes where they cool, then through super heaters in the third pass and the economiser heating surfaces in the final pass, where temperature of the flue gases will be reduced to the optimal temperature for flue gas treatment. The flue gases are injected with urea to reduce Nitrogen oxides (NOx), by this Selective Non-Catalytic Reduction (SNCR) treatment method. Flue Gas Recirculation (FGR) reduces NOx emissions further, by off-setting the intake combustion air with exhaust gas containing depleted Oxygen. Following cooling, the gases are further dosed with calcium hydroxide and powdered activated carbon to remove acid gases and other pollutants, including heavy metals. The gases then pass through filter bags and up through the 90m stack for release to atmosphere, whilst the Air Pollution Control residues (APCr) captured from the bag filter are conveyed into an enclosed silo prior to dispatch. The Emission Limits Values (ELVs) as set by the IED are modelled, and this demonstrates that the ELVs will be met during normal operation. When the waste is burned on the grate, the agitation causes the waste to pass along the grate so it is exposed to maximum oxidation to achieve a complete burnout. Any remaining ash known as Incinerator Bottom Ash (IBA) falls into a water bath or Quench, for cooling, prior to collection and storage in the ash bunker within the main building. The IBA will be removed from the bunker by a grab into a collection vehicle for removal off site. Heat, as steam, from the combustion process is recovered to drive a steam turbine, which in turn generates electricity, for self-use and export to the National Grid. Steam will also be extracted from the turbine and fed into a steam network linked to the Michelin Tyres factory for process and heating purposes for Michelin or a future potential industrial user at that site, and potentially also available for other future users through some form of heat network. Waste heat is removed via a finned tube, air cooled condenser. The heated water from the economizer also pre-heats the Boiler feedwater, increasing overall efficiency. Odours are controlled by storage of wastes inside an enclosed building, fitted with a fast acting roller shutter door. Whenever the new incinerator is operational, the air is drawn in from the reception hall, via the bunker into the combustion process. During periods where the incineration process is not operating, such as during planned maintenance, the air is treated via an activated carbon filter. Dispersion modelling for odour emissions from the carbon filter system was provided, and demonstrates that the threshold given in SEPA Guidance will be met at sensitive receptors. As required by the IED (Annex VI) continuous monitoring will be carried out of temperature, oxygen levels, flow rate and pollutant concentrations in emissions to air, together with periodic monitoring to check concentrations of heavy metals, dioxins and other species which cannot be monitored continuously, and to verify the Continuous Emissions Monitoring Systems (CEMS). The processes of testing, and systems used for monitoring are all designed to meet set European and British standards and criteria, and any independent analysis will be undertaken by accredited test houses. Annual audit monitoring of emissions to air will also be undertaken by accredited contractors employed by SEPA. An Air Quality Assessment (AQA) was undertaken, that took into account dispersion modelling (of pollutants) using ADMS5.1.2.0 model, local background baseline data (where available) and 5 years of meteorological data. Other background data, where no local baseline data was available, used worst

case data, making the modelling very conservative. The AQA assessed the predicted impact of emissions to air, on both human health and ecological receptors, and is based on a ‘worst case’ scenario, assuming that all pollutants are emitted at the level of the ELVs. Actual emissions would normally be much lower with good management control and abatement. The model also took into account the combination of emissions during commissioning of the new plant on diesel, whilst the Existing EFW Plant one was operating at maximum ELVs and the adjacent Michelin factory boiler was operating at the same time. SEPA is satisfied that the conclusions drawn in the assessments are supported by the results, and that there is no unacceptable risk to human health or the nearby ecological receptors. All solid and liquid fuels, lubricants and chemicals are stored to a high standard. The techniques used include silos with dust filtration to remove particulate matter (dust) from vented air during filling, and tanks with secondary containment and safety devices to prevent overfill. The majority of operations on the site will be undertaken inside buildings in order to contain odour and noise. Impermeable hardstanding will be used for all higher risk external areas and roadways to prevent potential groundwater and soil contamination. Water minimisation techniques have been used where possible, including dry scrubbing systems. Uncontaminated water will be captured from roofs for use in the toilet facilities, and much of the waste process water will be retained for use in the ash quench facility, where the ash is cooled to a low enough temperature to make is safe to handle. Excess process water, surface water from high-risk areas, such as the chemical or oil storage areas, and foul sewage will discharge to the public (Scottish Water) foul sewerage system where it goes for secondary treatment. Surface water from other areas will discharge via interceptors to the Scottish Water surface water sewer. A retention tank will be located on the site to prevent inundation of the system in times of high rainfall. The plant floor levels are designed to be above the 1:200 year flood level, although an area of the car park may be vulnerable to flooding from offsite sources beyond 1:50 year events. Boiler feedwater and return condensate from Michelin are treated on site. Noise levels will be minimised at current and future off-site receptors through the design and selection of equipment and techniques. These include acoustic enclosures, noise barriers, acoustic panelling, acoustic lagging, vibration damping, impact deadening, attenuators, steam and air diffusers, vibration isolation mounts, inertia bases (eg for mounting of the turbine), vibration monitoring of rotating machinery (eg fans) and noise reduction through component selection. A tank containing water is retained for fire-fighting purposes, and all areas of the plant have been designed to minimise fire spread, and capture contaminated water so that it cannot escape to the water environment. The Operator has an accredited Integrated Management System (IMS), and will apply for site specific accreditations over the first year of service delivery. The existing EFW plant is to be de-commissioned, however, parts of it will be retained, such as the weighbridge, the fire-water storage, water treatment, and the existing tipping hall, which will be retained for delivery and manual sorting of bulky wastes, by removing recyclates including metals, and items unsuitable for incineration. The non-recyclable waste will then be shredded and sent for incineration to the New EFW CHP Plant. The original permit has been subject to many variations and contains a number of obsolete conditions. It is proposed to rescind all conditions and replace them with the most up to date template conditions for a waste incineration permit, with a small number of bespoke conditions, some of which are designed to capture the changeover from one plant to another. It will also include a Condition that prevents both the old and the new plant incinerating waste simultaneously during commissioning, and prevents incineration at the Existing EFW plant once the new EFW CHP Plant has been commissioned.

Glossary of terms

APCr - Air Pollution Control Residues AQMA - Air Quality Management Area AQA - Air Quality Assessment BAT - Best Available Techniques CO - Coordinating Officer CHP - Combined Heat and Power CFD - Computational Fluid Dynamics C&I - Commercial and Industrial Waste CV - Calorific Value EFW - Energy from Waste ELV - Emission Limit Value EALs - Environmental Action Levels FGR - Flue Gas Recirculation HAPP - Heat and Power Plan IED - Directive 2012/75/EU on industrial emissions (integrated pollution prevention and

Control)(Recast) known as the Industrial Emissions Directive IBA - Incinerator Bottom Ash MSW - Municipal solid waste MEB - MVV Environment Baldovie Ltd MRF - Materials recycling facility IMS - Integrated Management System PPC 2012 - The Pollution Prevention and Control (Scotland) Regulations 2012 RCV - Refuse Collection Vehicles RDF - Refuse Derived Fuel RHS - Relevant Hazardous Substances SNCR - Selective Non-Catalytic Reduction SUDs - Sustainable Urban Drainage System SSSI - Site of Special Scientific Interest SAC - Special Areas of Conservation STR - Supporting Technical Report TTWG - SEPA Thermal Treatment of Waste Guidelines VOC - Volatile Organic Compounds

2 EXTERNAL CONSULTATION AND SEPA’S RESPONSE

Is Public Consultation Required - yes

Advertisements Check: Date Compliance with advertising requirements

Edinburgh Gazette 30/5/2018 to 03/6/2018 notices.

Page 1027. Complies with PPC advertising requirements.

Dundee Courier 30/5/2018 Complies.

No. of responses received: No responses were received.

Summary of responses and how they were taken into account during the determination: Not applicable – no responses received.

Is PPC Statutory Consultation Required – Yes

Food Standards Scotland: Yes – Letter sent out 14/5/2018. Letter of response dated 15 May received. FSS stated that ‘Based on the application and provided that the applicant complies with the relevant SEPA guidance and all other relevant PPC Guidance Notes and Regulation, Food Standards Scotland considers it unlikely that there will be any unacceptable effects on the human food chain from the emissions from this installation. This has been considered throughout the application determination and particularly in the overview of the Human Health Risk Assessment, and relevant Conditions in the Varied Permit relating to emissions will ensure that there are no unacceptable impacts on the human food chain.

Tayside Health Board: Yes – Letter sent out 14/5/2018.

Response dated 22 May received by email. NHS Tayside indicated that to make an assessment on human health, the emissions must be measured, and if SEPA is aware of emissions that may impact on human health, that the permit should not be granted. In addition, it was stated that emission standards are set at a level which ensures that the most vulnerable people are not harmed. This is dependent on the site operating in line with management plans, and it was noted that there were previous issues with management processes at the site. The existing installation is now in the hands of a different company, with more extensive experience of running incineration plants in Europe and in England, and have extensive technical competence. The new plant under construction, is a less complex moving grate technology, and will be operated by experienced and technically competent personnel. Management plans for similar plant have been provided, and more site specific procedures will be worked up now that final design is complete. It was noted by NHS Tayside that the Emissions Impact Assessment concluded no risk to human health, and that the risk of cancer had been considered at the older Baldovie incinerator at the time, and that health data on cancer was a crude measure of health, and did not include all cancers. The emissions of dioxins and furans on the original IPC Permit, issued in 1996 for the existing plant, was limited to 1.0 ng/m3. This was reduced from to 0.1 ng/m3 by the Waste Incineration Directive, (in 2000), which was a very significant reduction. The existing plant had not been designed to meet that reduction, but is generally operated effectively, and exceedences have been rare. The new plant will be designed to meet the lower limit from the outset. NHS Tayside queried if the 3 primary schools had been considered. These were all taken into account in the modelling at individual receptors, and in every case, the modelling indicated that the impact would be negligible. All 3 schools are located to the west of the site, and away from the prevailing wind direction. NHS Tayside also queried if the wind turbines at Michelin site will have any impact on grounding of emissions from the stack at the new EFW. Studies undertaken by CERC (2012) on the impact from turbines in modelling of emissions, indicate that the effect can increase the maximum concentrations, (usually only very slightly where it does happen) or even decrease the maximum concentrations of pollutants through better dispersion. The information on the turbines was included into the modelling for completeness, and SEPA are satisfied that this has no change to the outcome of the assessment.

NHS Tayside queried the impact from potential asbestos on nearby residences from one area of the proposed new area of the site. This would have been outwith SEPAs remit at the commencement of construction, as this was not part of the permitted area. The construction company would require specific risk assessments to be in place, and the subsequent removal of such waste would have to be documented. SEPA can subsequently view such documents and take action if the disposal is inconsistent with statutory requirements for hazardous wastes. This is not a permit issue. NHS Tayside noted that noise levels modelling only refers to daytime hours. Specific conditions were placed into the permit to limit operational times for receipt of waste will to specified daytime hours from 1/1/2020 (unlike now where they can actually bring in waste 24/7), until the Operator can demonstrate, with the use of further modelling, or actual measured results, that this will have no impact. A final question asked the relevance of the Trade Effluent discharge provided as part of the application for a similar site operated by the same group. Its relevance is just to provide a typical characterisation of the effluent. The effluent will be subject to Scottish Water control via a trade effluent licence. This is not a permit issue.

Dundee City Council: Yes

Planning: Letter sent out 14/5/2018. No response received.

Environmental Health/Contaminated Land: Letter sent out 14/5/2018. Response received by email. Noted a potential 50%increase in vehicle movement numbers which may impact amount of time large single door is open. This was subsequently advised that although the vehicles numbers for this part of the site would increase, there would be a reduction in vehicles going into the adjacent waste transfer station, so the nett increase was marginal Also noted that background metal concentrations used annual mean concentrations rather than the maximum annual mean concentration over previous years. This had already been addressed as part of the original (withdrawn) application, and the updated background data indicated that there would be no impact on air quality.

Scottish Water: Yes – Letter sent out 14/5/2018.

No response received. It is noted that the foul effluent will be subject to the existing Scottish Water Trade Effluent consent.

Health and Safety Executive: Not applicable as this is not a COMAH establishment.

Scottish Natural Heritage (PPC Regs consultation): Yes – Letter sent out 14/5/2018.

No response has been received to the substantial variation. However, a response to the initial application (that was subsequently withdrawn) had indicated the potential areas that may be impacted via the Water Environment and this was taken into consideration. The respondee indicated that the facility will contain and treat all process and surface waste water and discharge into foul water sewers and surface water sewers, and there would be no pathway to any designated wetland sites.

Harbour Authority: Not applicable as there is no discharge into the harbour.

Discretionary Consultation – Yes

Consultee: Whitfield development group – Letter sent out 14/5/2018. Justification: This group was listed on the Dundee city council website as being the nearest community group, and had been consulted on the initial new permit application, prior to its withdrawal and subsequent submission as a variation to the existing permit. Summary of response and actions taken: No response received.

Enhanced SEPA public consultation - Yes

Details of enhanced public consultation At the prior suggestion of SEPA, the Applicant placed a written copy of the Substantial variation application in the Douglas Community Centre, to coincide with the initial advertising and it has remained at the Centre since.

‘Off-site’ Consultation - No

Transboundary Consultation - No

Public Participation Consultation - Yes

STATEMENT ON THE PUBLIC PARTICIPATION PROCESS The Pollution Prevention and Control (Scotland) Regulations 2012 (schedule 4, para 22) requires that SEPA’s draft determination of this application be placed on SEPA’s website and public register and be subject to 28 days’ public consultation. The dates between which this consultation took place, the number of representations received and SEPA’s response to these are outlined below.

Date SEPA notified applicant of draft determination 24 January 2019

Date draft determination placed on SEPA’s Website 25 January 2019

Details of any other ‘appropriate means’ used to advertise the draft.

N/A

Date public consultation on draft permit opened 25 January 2019

Date public consultation on draft permit consultation closed

21 February 2019

Number of representations received to the consultation None received by 28 Feb 2019

Date final determination placed on the SEPA’s Website

Summary of responses and how they were taken into account during the determination: Not applicable.

3 ADMINISTRATIVE DETERMINATIONS

Determination of the Schedule 1 activity

As detailed in the application for this substantial variation, and clarified in the response to the Further Information Notice submitted on 30 August 2018. This is specified in the draft Permit Variation – Schedule 1 – Paragraph 1.1.3

Determination of the stationary technical unit to be permitted:

As detailed in the application, and described in the draft Permit – Schedule 1 – Paragraph 1.1.4

Determination of directly associated activities:

As detailed in the application, and described in the draft Permit – Schedule 1 – Paragraph 1.1.5

Determination of ‘site boundary’

As detailed in the application and inserted in Figure 1 in the draft Permit Schedule 1 paragraph 1.2. The boundary for the Permitted Installation is significantly extended.

4 INTRODUCTION AND BACKGROUND

4.1 Historical Background to the activity and variation

Dundee has had an incinerator for the disposal of municipal solid waste since 1979. The original plant was closed in 1995, and the existing Energy from Waste (EFW) plant, began operating in 1999. However, this plant is now nearing its end of life, and it is to be replaced with a new EFW CHP plant as part of the residual waste contract for Dundee City Council (DCC) and Angus Council. The new plant will be located next to the existing plant which will be decommissioned once the new plant is fully operational. (See Figure 1 for location). The proposed new plant, which has Planning Permission, will have a design operational throughput capacity of 110,000 Tonnes per annum of non-hazardous waste, based on an LCV of 10.5 MJ/kg (and a maximum operational throughput capacity of 153,000 Tonnes per annum as and LCV of 7.5MJ/kg. It will treat residual (non-recyclable) wastes from Municipal and similar commercial sources, following prior segregation in line with the Scottish Governments Zero Waste Policy.

The new EFW CHP Plant will be a moving grate type of incineration plant, and the air emissions treated via an abatement plant designed to minimise NOx, acid gases, organic compounds and particulates (including metals and dioxins/furans). The plant has a thermal input capacity of 39.9MWth and is designed to operate in Combined Heat & Power (CHP) mode, enabling the power and heat generated during the process to be provided to third parties, in keeping with current Scottish Governments Policy. These include power to the National Grid, and heat, as steam, to Michelin Tyres. This will reduce the local emissions to air as the heat provided will reduce the amount of time that Michelin will run their gas boilers during normal operations. In addition, the higher stack from the new EFW will increase dispersion, and reduce pollutant concentrations in the vicinity around the New EFW CHP Plant’s stack. The PPC Permit was issued on 24 November 2005, (replacing the original permit issued under the Integrated Pollution Control (IPC) Regulations due to a change in the primary legislation. The existing Permit has had numerous variations, prior to consolidating it in in 2012. Since then, it has had another 4 subsequent variations, and there are numerous conditions that are no longer relevant, including several time-bound actions which have been met. Both the Existing EFW plant, and the proposed New EFW CHP plant have to meet the same standard IED ELVs. The Operator is keen to have an up to date permit and has confirmed that they are satisfied with the proposal to replace all schedules with the latest permit template version, where relevant, along with the bespoke conditions required for the proposed New EFW CHP Plant, to cover aspects such as prior commissioning conditions. Several conditions were discussed further to ensure that they were suitable, including:

Interpretational queries over the commissioning, cessation, first operation, and impacts of timing on the Prior Operating requirements;

Minor changes to storage capacity details now that design is finalised;

the maximum throughput of waste as well as the design throughput and specific heat values or CV around which it is based (to ensure that the concentration of pollutants in the gas flow would not lead to any impact on the environment or on human health, and air quality standards would be met;

potential for heat (as steam) to go to other users due to potential for changes at the Michelin plant;

allowed extra time to develop the heat and power plan further, due to the potential changes at the adjacent Michelin Plant;

Discussions on the borehole construction during actual site construction of the EFW and methods to protect the boreholes;

A more detailed noise BAT assessment for individual noise sources, and taking into account tonal noise, receptors at height etc

opening times for waste deliveries were reduced to standard for waste facilities, but have subsequently been amended to reflect the Planning documentation and modelling;

correction to a typographical error regarding the ELV for odour;

capacities for the containment of contaminated water were confirmed;

minor corrections to detail, eg no baling will take place, there is no direct export of electricity to the Michelin plant, removal of pressured steam from raw materials, changes to several wastes to be included,

Details of changes made to template conditions following discussions with the Operator are available in section 8 on changes (see below). A further draft was sent out to the Operator. They could not accept the proposed hours, and noted the timescales for submission of several reports were unachievable, (as they would be due prior to the issue of the variation). The timescales for the reports were amended, and still allow enough

time for assessment by SEPA. The change to the hours for accepting waste will now take place only from 31 Dec 2019. This allows the Operator time to undertake additional noise monitoring and modelling and submit a variation to SEPA to extend the hours.

Figure 1 – Location of site The plant is situated within the Dundee City Air Quality Management Area (AQMA).

4.2 Description of activity

The activities applied for are:-

the incineration of non-hazardous waste under PPC Part A, section 5.1(b); and

the disposal of non-hazardous waste at an installation with a capacity exceeding 50t/day under PPC Part A, section 5.4(a)(iii) by means of pre-treatment for incineration.

4.3 Outline details of the Variation applied for

There is an existing incineration plant in Dundee, now operated by MEB. This existing plant is nearing the end of life. Dundee City Council who had majority shares in the existing plant until 2017, tendered for a joint waste solution with Angus Council, and selected a solution from MVV Environment Limited, who own MEB, that includes the replacement of the existing incineration plant.

The replacement plant is the subject of this substantial variation application, and the applicant MVV Environmental Baldovie, (MEB), has been awarded the contract to build and operate the new Energy from Waste/Combined Heat & Power (EFW CHP) plant. The new EFW CHP plant will incinerate the residual Municipal waste from the area covered by Dundee City Council and Angus Council. The plant is designed to have a throughput capacity of 110,000t/yr. Recyclable waste arising from the area will be sorted at the kerbside, to agreed targets to meet the requirements for household waste recycling. The energy generated will be used for both power and heat. The Operator will be handling all of the Municipal waste in the area under a new contract, and the incineration process is only a part of the overall Dundee City & Angus Residual Waste Project. Waste from the adjacent Transfer Station will be sorted, and the residual wastes sent for incineration. Bulky wastes, from eg household collections within the contract area, will be further sorted or treated in the tipping hall of the Existing EFW Plant prior to incineration. In addition residual waste from other third party commercial and industrial contracts will be accepted into the hall for screening and sorting as required. The proposed new EfW CHP plant will use an inclined reciprocal moving grate which agitates the

burning waste to ensure complete combustion during the process. The waste will be burnt at 850⁰C for a minimum of 2 seconds, as required by the Industrial Emissions Directive (IED), in a 4-pass vertical boiler. The first two passes are empty, to allow for cooling of the gases, whilst the third pass is a super heater, and the economizer makes up the fourth pass. After moving through all 4 passes, the gases are cooler and can pass to the abatement plant for treatment, prior to release from the 90m high stack. Continuous monitoring of the temperature, oxygen levels, and IED specified parameters (CO, NOx, TOCs, PM, HCl, HF and SO2) will take place, along with NH3 and N2O, with periodic sampling for heavy metals, Dioxins/Furans, and other organic compounds. In the abatement plant, air emissions will be treated, using automatic dosing, injected directly into the waste gases, to reduce contaminants. Urea in the Selective Non-Catalytic Reduction will reduce NOx, which will be further reduced by Flue Gas Recirculation (FGR), Calcium hydroxide will reduce the acid gases in a dry scrubbing process, and a powdered activated carbon plant will reduces dioxins/furans. The gases will then flow through bag filters where the particulates will be retained prior to transfer into a silo for subsequent removal. There will be suitable storage of all raw materials used for the abatement at the site. Municipal wastes and other non-hazardous commercial and industrial wastes will be delivered into the waste bunker, within the waste reception tipping hall, a contained building. The air within the tipping hall will be drawn via the waste bunker and extracted for use in the combustion activity. This will create a negative pressure to prevent odour and dust escape from the plant. During times when the combustion activity is off (eg for maintenance), an alternative method (carbon filter) will be utilised. A Heat & Power plan submitted was with the application confirming that the heat is to be used by the adjacent Michelin factory, reducing Michelins use of virgin fuels and emissions from their Boilers. Michelin have indicated they will be leaving and the plant may be taken over by another manufacturer or instead, supplied via a heat network to other users. Power will be supplied to the National Grid. Steam produced in the boiler will drive a steam turbine which will generate the electrical power for export to the grid, and self-power at the plant, and steam will be extracted from the turbine for supplying heat to Michelin and potentially other users. The plant will be a Combined Heat and Power (CHP) ready plant from the start. The design thermal input capacity of the plant is 39.9MWth, based on the plant operating for 8,000hours per year.

Waste water generated during the process will be utilised as far as possible for ash quenching. Any that cannot be utilised in this way, and the surface water from higher risk areas of the plant, will be discharged via the public foul sewage network, operated by Scottish Water, and subject to secondary biological treatment. Surface water from other (lower risk) areas will be drained via permeable paving, prior to discharge to the water environment (via SW surface sewer serving the industrial estate). This discharge will be throttled to reduce the risk of surcharging, and a large underground tank will enable the retention. A full class 1 retention interceptor unit will be used to retain any oil due to vehicle movements, parking etc. The oil storage tank will be integrally bunded, with level control and leak detection, and tertiary containment. The delivery apron will have a large full class 1 retention interceptor laid to a fall, capable of taking the full volume of the largest compartment of the delivery vehicle, should there be a failure of the vehicle storage. The residual wastes, (IBA, APCr) generated by the process will be captured, stored separately in silos or the ask bunker, (or skips for the Existing plant until it ceases to operate), and tested in accordance with the permit requirements. Full Planning permission for the new plant was given by DCC in March 2017.

4.4 Guidance/directions issued to SEPA by the Scottish Ministers under Reg.60 or 61.

Access to information direction on 17 April 2013 requires SEPA to publish decisions on its website, which is required for any PPD application, including this one.

4.5 Identification of important and sensitive receptors

To the north of the site, there is a waste transfer station, now operated by MEB also, beyond this is a disused factory, a main road and beyond that housing. To the east, there is the large Michelin Tyres factory, and another industrial estate beyond. To the south is a scrapyard, river then housing, and to the west is mostly open land out towards a school and various recreational areas. Key receptors are :-

a) Human health receptors, particularly within the Dundee Air Quality Management Area (AQMA).

b) Ecological areas, such as Special Protection Area’s (SPAs), Special Areas of Conservation (SACs), RAMSAR sites (protected wetlands) and Sites of Special Scientific Interest (SSSIs)

A comprehensive list of sensitive receptors has been considered for the air dispersion modelling, where human health and nearly ecological receptors are taken into account to ensure that there is no significant harm caused by the proposed operation. Sensitive receptors are also considered in the Noise and odour modelling. a) The nearest residential receptors are approximately 387m south, and 402m north of the new

plant. Other non residential receptors include the Police station on Balunie drive (354m to the south), Michelin Athletic club (461m to east), BMX track 289m west. The nearest school is Claypotts Castle primary school, 857m to the south. The receptors have been modelled at heights of 1.5m generally, which is representative of inhalation height for a human at ground level, and also at 7.5m for certain residences, representing a third floor level to allow for any higher elevated properties such as flats.

A full list of the receptors is provided in section 4.2 of the AQA document, submitted as part of the application as the Emissions and Impact Assessment. This document was also used for the Planning application, and a terrain map of the receptors showing their location relevant to the plant is copied below. The red line is the boundary of the operational areas, required for Planning and includes areas that will not be part of the Permit variation application, such as the lay down area to the west of Forties road.

The Dundee AQMA covers the city, and is designated due to high NOx and particulate levels, primarily from traffic. The full extent of the AQMA is shown in the terrain plan below as a gray overlay. The site boundary is shown in red – but again this area is greater than the Permitted Installation will cover.

b) Discrete designated ecological receptors up to 15km from the site were assessed, including

Special Protection Areas (SPAs), Sites of Special Scientific Interest (SSSIs), site designated under the RAMSAR convention, and Special Areas of Conservation (SACs). Other sites such as waterbodies, woodlands, local nature reserves (LNRs) have also been assessed. A full list of all sites (ecological receptors) is provided in section 4.2 of the AQA document submitted as part of the application Emissions and Impact Assessment, and the terrain map of these sites is copied below to indicate the scatter and direction of receptors considered. The Firth of Tay and Eden Estuary (No 43 on the plan below, is a designated SPA, RAMSAR, SSSI and SAC) and is considered to be an internationally important wetland site. It is located approximately 2.8km from the Permitted Installation. There are no designated sites within 2km. The impact of air emissions on ecological receptors is considered in more detail in section 5.2.6.

5 KEY ENVIRONMENTAL ISSUES

5.1 Summary of significant environmental impacts

The process is a standard moving grate incineration plant capable of burning a maximum of 153,216 tonnes of non-hazardous waste each year, but based on a throughput of 110,000 tonnes at a CV of 10.466 MJ/kg. The main significant impacts of the proposed facility are emissions to air and water, use of raw materials, generation and management of residues, odour and noise. These are discussed in more detail in Sections 5.2, 5.3, 5.13, 5.14, 5.7 and 5.17 below, together with details of the BAT techniques for their management to minimise the impact and polluting potential. A simplified process diagram is reproduced below from the application:

5.2 Implications of the Variation on - Point Sources to Air

The existing fluidised bed plant is permitted to burn up to 150,000t/pa but in the last few years has generally incinerated only around 90,000te/annum partly due to the type of furnace and its lack of availability. This can be due to less operational availability due to greater maintenance requirements, and blockages caused by clumping of waste, eg if damp, and partly because the maximum tonnage throughput can only be achieved by using a waste with a lower calorific value, when in reality, the waste is more mixed. The new moving grate CHP EFW plant will theoretically be able to incinerate up to 153,216te/annum due to less maintenance from the proven moving grate technology, which has far less moving parts, and does not rely on the waste being levelled to a specific depth like the fluidised bed plant, which has often lead to poor combustion conditions if there is any clumping in the waste. In reality, the waste throughput, which is designed at 110,000te/annum based on an average CV, is likely to be somewhere between the two figures. Short term concentrations of pollutants are unlikely to vary from the existing EFW emissions, however total annual emissions from the plant may appear to increase due to lower down time required for plant maintenance. Emissions from the New EFW CHP Plant will be from a higher stack, which will provide greater dispersion into the environment and a lower predicted maximum ground level concentration of pollutants. Emissions from the New EFW CHP Plant may also be offset by a reduction in emissions of certain gases from the Michelin Boilers, which will operate less frequently under the agreed contractual arrangements. Planning Condition 17 (16/00916/FULM, issued by DCC) requires that the existing EFW plant, and the new EFW CHP plant may not both burn waste at the same time, so during commissioning of the new EFW CHP plant where waste feed is taking place, the existing one will not feed waste into the incineration furnaces, although it may operate on diesel. The existing plant will however be retained and utilised until such time as the new EFW CHP plant is fully operational.

5.2.1 Air Quality Assessment (AQA), impact and emissions

A key issue associated with the proposed development is the extent and impact of emissions to air from the installation. The main emissions come from the incinerator unit, or ‘Boiler’, where combustion takes place, and include carbon monoxide, oxides of nitrogen (NOx), oxides of sulphur (SOx), hydrogen chloride, (HCl), heavy metals, particulate matter (PM) and volatile organic compounds (VOCs) which may include dioxins and furans in addition to carbon dioxide and water vapour. These substances when emitted from incineration appliances are subject to the requirements of the Industrial Emissions Directive (IED) which requires compliance with specific emission limit values (ELVs) as set out in IED Annex VI, and are treated to ensure that the ELVs are met.

The detailed impact of emissions from the proposed development and their impact on Air Quality Standards, Human Health and Habitats are contained in the following documents submitted with the application;

Emissions and Impact Assessment Report (28 March 2018) – Section 2 on Point Source emissions to air; Section 3 on Human Health, Appendix B – the Air Quality Assessment (AQA) Report (including Human Health) and Appendix C – the Habitat Regulation Assessment (HRA)

Addendum Report (29 March 2018) – Appendix D on emissions, and Appendix G on Human Health and Ecology,

In the UK, air quality standards and objectives for major pollutants are described in The Air Quality Strategy for England, Scotland, Wales and Northern Ireland 2007. In Scotland these air quality objectives are implemented via the Air Quality (Scotland) Regulations 2010. For any pollutants not described in this Regulation, Appendix D of the PPC horizontal guidance note H1 can be used. Between these documents, Environmental Action Levels (EALs) for short and long term protection of human health and the environment are provided. The Air Quality Assessment (AQA) contains the methodology and information on how the atmospheric dispersion modelling was set up and undertaken. The study used the latest air dispersion model ADMS5.1.2.0, assumes the worse case scenario – ie that the emission is at the level of the IED daily and 30 minutes ELVs, and occurs at this maximum constantly). The IED ELVs will be set into Schedule 6 of the Permit, and are the maximum concentration that can be emitted over a given specified time period. The model takes account of the effects of prevailing meteorological conditions from 5 years of data from Leuchars, a long term monitoring site in Fife, building downwash effects, local topography and local ambient air quality. The modelling approach and the details of model input and model set-up have been assessed by SEPA’s air dispersion modelling specialists and SEPA is satisfied that these are satisfactory. Outputs from the ADMS model are used in the assessments of impact on air quality, on habitats, and on human receptors. A sensitivity assessment was undertaken using the air dispersion model AERMOD to check the validity of the modelled outputs. (Section 4.2.18 of the AQA) This showed that for the main parameters of concern in the AQMA, that the ADMS derived impact predictions are higher than AERMOD predictions. This confirms that a more conservative model output was used, adding confidence to its validity. Various sensitivity analyses were undertaken to determine which modelling options should be included or not. This has taken into account the terrain, the effects from nearby turbines and buildings, coastal impacts, and the local meteorological data (Broughty Ferry and Dundee Mains Loan) against the long term data from Leuchars. The model used considers a gridded domain, and the output gives the likely impact for each discrete receptor.

5.2.2 Stack Height Screening Assessment

A stack height screening assessment was undertaken to determine the most appropriate discharge stack height. A sensitivity screen analysis was carried out using a range of possible stack heights between 70m and 110m. The results of the stack height screening assessment are provided in Appendix F of the AQA submitted with the variation application. The assessment used the ADMS dispersion modelling, (discussed above) taking into account meteorological data, terrain, surface roughness, wind turbine and building effects. The result indicated that 90m was the optimum stack height, whereby the most significant reductions had already occurred, and additional height would offer little additional benefit. 90m was therefore used for the main modelling assessment to predict the impact of emissions (see below). SEPA accepts this assessment of the data.

5.2.3 Predicted Environmental Impact of Emissions

Air quality limit values and objectives are quality standards for clean air, and may be long term (annual average) standards relating to pollutants which may have a chronic impact on health or on the environment, or short term standards, expressed as 15 minute, 1 hour or 24 hour averages where short exposure can lead to acute impacts. Some pollutants can have both long and short term standards. In Scotland, the following table indicates the limit values or objectives that are relevant for the emissions from the incineration of waste, and are used to assess the contribution from the proposed plant and its potential impact.

Where there are no direct Scottish quality objectives, the pollutants are assessed using Environmental Assessment Levels (EALs) provided in horizontal Environment Agency SEPA guidance or by the Health & Safety Executives (HSE) workplace exposure limits.

Details of the EALs used in this assessment are provided below.

Dioxins and furans, dioxin-like PCBs and some trace metals do not have specific air quality objectives limit values or EALs, and are assessed separately in a human health risk assessment. (See section 5.2.5 of this document). A comparison of the predicted maximum ground level Process Contribution (PC) with Air Quality Standards, based on emitting at the maximum IED ELVs, was provided in the AQA, to indicate the likely predicted long term and short term environmental concentration (PECs) during normal operations. In order to set the baseline for the model, the background concentrations of the pollutants needed to be established. The background data used initially in the AQA (April 2017) is shown below.

AQA – Background pollutant concentration data

Some of the background data provided the in the AQA was based on a long term rural monitoring site called Auchencorth Moss. SEPA queried the validity of using rural background information with the applicant during the planning stages of the project, and prior to the current PPC application to vary the Permit. Additional data was therefore provided in the addendum report, submitted with the application to vary the Permit, and is discussed further, below the results table. In 2013, the Dundee City Council area was declared an Air Quality Management Area (AQMA) due to exceedences of air quality objectives for the 1 hour and annual mean NO2 and the annual mean PM10. AQA predicted impact – normal operation - results and screening The first stage of the impact assessment (see summary results below) considers if the long-term Process Contribution (PC) result is >1% of the relevant long term standard, or the short term PC result is >10% of the short term standard. This is based on emissions from the plant being at the environmental limit value, as set by Part 3 of Annexe VI of the Industrial Emissions Directive (IED) for the maximum allowable period. A comparison is also made against the actual emissions from the existing plant.

(It is assumed that 100% of the Volatile Organic compounds (VOCs) emitted by the proposed EFW will be benzene, representing a worst case).

In the above results, which are the maximum point of impact on the grid, the majority of pollutants could be screened out at this first stage as being insignificant, ie below the relevant short or long term PC against the relevant environmental limit. However, long term NO2, VOCs (as Benzene), Benzo(a)pyrene, arsenic, cadmium and nickel did not screen out immediately at this first stage, and could potentially be significant. These go on to a second screening stage, comparing the long term PECs.

In this second stage, where the PEC is <70% of the relevant environmental limit (EAL), these pollutants can also be screened out as insignificant. NO2, VOCs (as Benzene), Benzo(a)pyrene, arsenic, cadmium and nickel are shown to be below this 70% threshold and were therefore also screened out as being insignificant. Due to the queries SEPA raised regarding the use of background data from a rural location and NO2 data, the addendum report (Appendix G – Air Quality, Human health and ecological receptors) provided further information on NO2, Heavy metals, TOC, HCl, PCBs and dioxins and furans. This information demonstrated that even taking into account the urban and local background concentrations for further modelling purposes, that there is no significant impact, however, these are discussed in more detail below. NO2 Dundee Mains Loan long term sampling location (DUN1), in the city centre, provided the NO2 background data, (background annual mean of 11.6ug/m3) used initially. However, SEPA queried how this compared to local sampling undertaken during the planning period in order to verify if this was representative. A local sampling location at the nearby Kellas Road, representative of nearby residential areas within an urban environment, gave a result of 12.0ug/m3. The predicted impact was re-assessed using this elevated background concentration for all nearby receptors, and the point of maximum impact on the grid. The PC as % of the EAL was marginally above 1% at 4 receptors (3 of which are residential) of the 111 checked, however, as a second screening stage, the PEC was well below 70% of the EAL for these receptors and the impact was therefore found to be insignificant. The EAL was met at all sites. For comparison, the Scottish Air Quality website provides modelled background data for 1km grids, and the estimated NO2 concentrations for the area around the proposed site were marginally lower, at 9.2 to 11.0ug/m3. In addition, the background data includes the existing incineration plant process contribution, which will no longer be operating, so the modelling is very conservative. Even though the existing plant is situated within the AQMA, the actual emissions have no significant impact on the NO2 pollutant concentrations, and the PEC is well below the EAL for both long term and short term standards, NO2 can be elevated in parts of the AQMA, especially around main transport routes, due primarily to vehicular emissions. The replacement of the existing EFW plant with the proposed EFW CHP is likely to marginally reduce the NO2 emissions marginally as shown in Table 33 even when using maximum ELVs to model this plant on. Heavy metals No local sampling for heavy metals is undertaken at Dundee for use as background concentrations, so the model used the worst case scenario based on the urban sampling location, Motherwell South.

The results in the AQA were based on the maximum annual mean results over 2011, 2012 and 2013, which were the most recent results available, to provide the PEC data. 2013 data was selected for use in the assessment, as it provided the highest average concentrations for all metals except Total Chromium, Chromium VI and Cobalt which were based on the average background concentrations across all three years, rather than the maximum across any single year. It was noted that the annual average concentrations for Total Chromium and Chromium VI for 2011 were greater, and for Cobalt, the annual average concentration was highest in 2012. Recalculated data was subsequently provided in the addendum report, (see below) for these three substances.

The recalculation, based on the maximum annual average of the three years of results, for these substances confirms that there would be virtually no impact on the PC or PEC results, and they would remain below the long term threshold, except for the Chromium VI PEC. This is because the Motherwell south background concentration already exceeds the annual mean EAL by around 60%, however, the actual PC is still only 0.5%, well below the 1% threshold at which further assessment would be required. There is no evidence that Dundee has similarly high background Chromium VI concentrations to the heavily industrial Motherwell area. The PC/EAL% results are unchanged, however, the recalculated PEC/EALs(%) are as follows:

Chromium II/III = 0.06;

Chromium VI = 230; and

Cobalt = 0.01 SEPA is satisfied that the modelling is conservative, and the impact from the proposed new EFW can be considered insignificant. Other Similarly, where no local monitoring data was available for other substances such as CO, SO2 and Particulate Matter, long term data was taken from Edinburgh St Leonards site, as this was considered to be comparable with the urban setting for the proposed Dundee site. No local or urban long term background data was offered in the AQA for TOC, HCl, Ammonia or Dioxin like PCBs, and the Operator was asked to look at more appropriate background data sets than Auchencorth Moss rural background monitoring site, or justify why it was considered suitable. (The data from Auchencorth was used initially as it is the only automatic monitoring undertaken in Scotland). In the Addendum report, for VOCs (benzene), the background results from 2 non-automated benzene monitoring sites at Glasgow and Grangemouth were provided. (See below). An assessment using these background concentrations, indicate that although the Long term PC would be above 1% of the EAL, the PEC would be much lower than 70%, and EALs would be met for both short and long term concentrations. The increase due to the proposed site is therefore considered insignificant.

Background HCl data from Edinburgh was reviewed against the Auchencorth data. As the EAL is a short term objective, the maximum 1 hour mean was reviewed. The maximum Auchencorth result for 2013-2014 was 3.4ug/m3, more than twice that at Edinburgh which was 0.7ug/m3, therefore the result using Auchencorth background data was valid. The impact was considered to be insignificant. Similarly, Ammonia at Auchencorth for 2013-14 was 1.2ug/m3 as an annual mean, and Edinburgh result was 1.1ug/m3. The use of the Auchencorth data was considered to be valid and the impact was insignificant. Auchencorth was the nearest monitoring site for Dioxin-like PCBs, but the urban site with the greatest number of measured concentrations was London. The predicted concentrations at the point of maximum impact were shown to be well below the thresholds of significance, and the EAL would be met. (Short term background was assumed to be twice the long term concentration).

Abnormal (short term) Operations An additional assessment was provided by the Applicant to show the potential short term impacts (where short term averaging standards are in use). The metals were each modelled, following EA guidance (Waste Incinerators: Guidance on impact assessment for group III metals – v4, 2016). This method involves up to 3 steps of screening. The initial screening is undertaken using a worst case, ie assuming each metal is emitted at 100% of the group ELV (ie 0.5mg/m3), to determine if at this artificially high concentration there would be an impact on the EAL. Where any PC exceeds 10% of the short term environmental standard, it could be potentially significant. In these circumstances, the PEC should be compared to the EAL, and if greater than 100%, step 2 would then be followed, where case specific emissions would be assessed. Of the metals, only Vanadium was above 10% of the short term standard, however, following the EA guidance methodology, the PEC was less than 100% of the EAL at just 25.5%, and therefore could be screened out without further assessment. NO2 was also above the 10% short term PC at 11.9%, and was taken to the second screening stage. At that point the concentration is considered insignificant if the short term PC (23.7ug/m3) is more than 20% of the difference between the long term background concentration (23.2ug/m3) and the relevant short term standard (200ug/m3). In this case it was 12.6%, and therefore could be screened out.

The method used throughout has been conservative. The results represent likely worst case and are based on the point of maximum impact, whereas beyond that point of maximum impact, the impact gradually reduces. The Company currently operate a similar plant in Plymouth, and data to confirm that they comply with the IED ELVs from that plant was supplied with the application. In addition to this, summary data of the continuous monitoring is publically available on a weekly basis, via their website.

5.2.4 Cumulative effects

For completeness, a cumulative impact assessment also considered 3 future scenarios:

The proposed EFW CHP operating on diesel during hot commissioning, whilst the old plant incinerated waste;

The proposed EFW CHP burning waste and the Michelin boiler plant operating together;

The proposed EFW CHP operating on diesel during hot commissioning, whilst the old plant incinerated waste, and the Michelin boiler plant operated all running together.

In the first of these scenarios, only pollutants that arise from the combustion of diesel (NO2, CO, PM10 and SO2) were assessed, as only these would have a cumulative impact with the waste incineration outputs. All concentrations were below 10% of the EAL and below the relevant air quality standard and were therefore not considered significant. (See Table 37 from the report below). Hot commissioning is anticipated to last for around 1.5 months, and only short term statistics have therefore been modelled.

In the second scenario, the 3 boilers at Michelin are operated with the first operating at 80% load, one on standby at 20% load, and one not-operating. This is a worst case, as the proposed EFW will be providing heat so the boilers at Michelin are unlikely to operate at these levels unless there is an issue with the steam extraction and delivery or during maintenance of these systems. As the Michelin boilers are gas fired, the only cumulative impact of significance is likely to be from NO2, as particulates would be insignificant. This impact was found to be beneficial compared to the existing situation (the existing EFW plus Michelin, compared to the new

one plus Michelin), with a reduction in the PECs of NO2, both in the short term and the long-term. (see Table 38 excerpt from the report below).

In the last scenario, a worst case of all, the proposed EFW facility is hot commissioning, whilst the old plant is operating on waste, and the Michelin boilers are also in use as per the previous scenario. This shows an increase in the overall PEC for NO2, to 40.6ug/m3 however, the PC is less than 10%, and the PEC is well below the air quality standard of 200ug/m3. Again this is insignificant.

No scenario has been presented for both the existing and the proposed new EFW incinerating waste at the same time as this is not an acceptable scenario. It is not clear that Michelin Tyres will continue to operate at this location following a much publicised closure announcement, due in 2020, however, Michelin is working closely with DCC and Scottish Enterprise to pursue new industrial or other uses at this site where the heat may be a contributing factor to attracting a developing industry, and other nearby sites which may also wish to use the heat via a heat network.

5.2.5 Human health

A Human Health Risk Assessment (HHRA) was undertaken, (This is discussed in Appendix B of the Emissions and Impact Assessment report, and the full HHRA is provided in Appendix E of the AQA) which considered the impact on human health arising from the potential worst case emissions from the proposed EFW CHP facility. The HHRA looks at Compounds of Potential Concern (COPCs) to health, which includes dioxins and furans, dioxin-like polychlorinated biphenyls (PCBs) and trace metals, and assesses the impact of an individual exposed for a lifetime, to the effects of the emissions and consuming mostly locally grown food as a worst case. It considers the proposed 30 year operational period of the plant, and has also taken into consideration the emissions from the existing plant. Concentrations of the COPCs are estimated at the point of exposure. The assessment, in section 3.3 of the report, is based on the Human Health Risk Assessment Protocol (HHRAP) methodology, using the Industrial Risk Assessment Programme (IRAP, version 4.5.6), which is a method approved by SEPA, and uses results from the atmospheric dispersion modelling used in the AQA. The two main pathways for exposure to humans are direct (inhalation) or indirect (ingestion of water, soil, vegetation, animal meat and products), however, other potential pathways include drinking water, skin contact and incidental ingestion. Some of the COPCs can have accumulative effects, becoming more concentrated higher up the food chain, so ingestion

of meat and milk is significant. The database of parameters is based on HHRAP default values. The model assesses the total dose of over 200 COPCs received over a lifetime by an individual through a combination of potential exposure routes, using a worst case scenario, by assessing each exposure as a worst case or maximum and adding these. It is very conservative. The model considers the receptor types ‘resident’, ‘farmer’ and ‘fisher’, and their likely diet, as well as whether they are adult or child receptors. For each identified land use area, the methodology is to select the locations that represent the maximum predicted concentrations or deposition rates and up to 9 receptor locations are selected per defined area. 10 areas of residential exposure were defined, and 2 farmer receptor areas, (both located beyond the residential areas, due to the nature of the site). (See locations below). At other locations not specifically considered, the predicted hazards are lower than the discrete receptors.

The following calculations were undertaken as part of the assessment, which considered the 13 residential receptors (eating limited locally produced food; assumes access to allotments – see Addendum report), and four farmers (eating proportionately more locally grown food than the residential receptors):

estimates of the combined carcinogenic risks and non-carcinogenic risks (Hazard Quotients, “HQs”) for all identified receptors to calculate the total Hazard Index (HI) of 1.0, which is the sum of the individual pathways HQs. (sections 3.3.1 and 3.3.2);

estimates of risk and hazards associated with the various pathways of exposure;

evaluation of infant exposure via breast milk to dioxins and furans with appropriate bio-transfer factors, (section 3.3.3); and

a comparison of the tolerable daily intake (“TDI”) of dioxins and furans with the UK’s Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment COT / TDI values, (section 3.3.3).

The contribution of the proposed new facility, with regard to exposure to dioxins, furans and dioxin-like PCBs, to the COT/TDI of 2pg I-TEQ kg-BW-1d-1 is less than 3% for the farmer receptors, and less than 0.3% for residential receptors. Breast milk intakes represent a short duration high intake, but when considered over the lifetime exposure, would be substantially below the COT/TDI. A cumulative assessment, considering both the existing plant and the proposed facility was also undertaken, and this showed the HIs for combined exposure were also well below 1.0 (Unity), indicating that highest exposure scenario of both plants would have no significant impact. The results from the HHRA indicate that the potential health risks for all nearby receptors are below the levels set for the protection of human health. Individuals are not subject to significant carcinogenic risk or non-carcinogenic risk arising from exposure either directly or indirectly to the COPC. The impact is therefore considered insignificant. SEPA has assessed the methodology selected and the way that this has been implemented, and considers that the conclusions of the risk model is satisfactory, and the risk to human health is not unacceptable. With good management and implementation of the flue gas abatement techniques as described, it is highly unlikely that the intake to any receptor will be close to the assumed worst case as modelled. Foods Standards Scotland and the Tayside University Hospitals NHS Trust (Health Protection Team) were both consulted on 14 May 2018. SEPA did not receive any comments from either organisation.

5.2.6 Habitats

For protection of ecosystems, the Habitats Directive (92/43/EEC), was transposed into Scottish law by the creation of the Conservation (Natural Habitats) Regulations 1994 (as amended). The emissions from the proposed incineration plant are required to have an assessment, to determine if the proposal is likely to give rise to a significant effect on European Sites. For undertaking the assessment, the air Dispersion model (ADMS) (referred to in the section on air quality above) was used to predict short and long term concentrations of pollutant across the grid and at specific receptors.

The short range deposition impacts on terrestrial sites are assessed, using Site Relevant Critical Loads, available from the UK Air Pollution Information System web database (APIS).

If the predicted Process Contribution (PC) of the proposed plant exceeds 1% of the Critical Level, the Predicted Environmental Concentration (PEC) is then reviewed, and if this is below 70% of the Critical Level, the installation is unlikely to have a significant impact on the habitat of interest. The Critical Levels are indicated are specific pollutant concentrations below which harmful effects are unlikely, and are given below (Table 4 excerpt from the AQA).

While a Process Contribution (PC) of <1% of the Critical Load is assumed to be a non-significant effect, exceedance of the 1% figure does not necessarily imply any significant impact. It is a value above which it is appropriate to undertake a more detailed assessment of effects. The significance of the exceedance depends on factors such as the duration of the impact, the proportional increase over current levels and the sensitivity of the habitats affected.

The Critical Load is used to assess the risk of impact on specific habitats, and is determined by the sensitivity of different designated features. The acid critical load is a measure of the degree of acidification, from acidifying compounds, above which acidification impacts may start to occur; the nutrient nitrogen critical load is the equivalent for the degree of eutrophication, from nutrient nitrogen deposition. (Exceedance of a Critical Load is not a quantitative estimate of damage to a particular habitat, but represents the potential for damage to occur).

The ecology aspects and results are discussed in the AQA, sections 2.4, 4.2.1, 4.2.22 and 4.2.25 and the detailed model results are presented in Appendix C of the AQA. The ecological sites considered are shown below:

All of the sites in the above terrain map were assessed however, there are just 4 designated European sites ie Natura 2000 sites that lie within the 15km PPC screening distance from the proposed plant. These are:

Firth of Tay and Eden Estuary SAC/SPA;

River Tay SAC;

Barry Links SAC; and

Tentsmuir NNR.

Investigation of the Critical Levels (CLevel) of the 4 designated sites identified above was undertaken using the APIS database. This database provides information on the most sensitive species in each designated area and this is used to estimate the worst case impact.

The background levels for both NOx and SO2 were well below the CLevel for each site and associated habitats. Modelling results show that the process contribution for atmospheric concentrations of both NOx and SO2 were below the 1% PC, with total atmospheric concentrations remaining well below the CLevel for each habitat.

The exception was annual mean NH3 when compared to the standard for lichens and bryophytes. This was higher due to background concentrations already being greater than the EAL. However, the maximum 24hr mean concentration was predicted to decrease with

the proposed EfW CHP facility emissions compared with the existing EFW facility emissions. The impact on ecological receptors from the proposed facility would therefore gradually decrease over time.

It is SEPA’s view that the proposal will not have a likely significant impact on the sensitive habitats considered, and is unlikely to exceed the relevant Critical Loads, or Critical Levels or have a detrimental effect on local sites of ecological interest.

5.2.7 Plume visibility

The potential visibility of the plume was discussed in section 6.3 of the AQA. Moisture in the warmer gases being emitted can condense to form a white coloured plume, and this cannot always be avoided, eg during low ambient temperatures. The ADMS calculates the likely occurrence and length of visible plumes based on the characteristics of the efflux parameters and the mixing ratio of the kg water : kg dry air in the plume. The modelling shows that there would be visible plumes of greater than 20m length during 45 hours per year, (or 0.5% of the time) compared with just 5 hours per year for the existing plant.

In accordance with SEPA’s H1 guidance, the impact of plume visibility would be classed as insignificant to low, as the plume length may exceed the average site boundary distance for less than 5% of daylight hours per year. Medium or lower impacts are considered acceptable, therefore it is SEPAs view that there is no significant potential impact from the plume.

5.2.8 Summary and Conclusion

The proposed replacement is unlikely to have any significant impact on the environment or human health, and air quality standards will be met. Modelling has been very conservative, and in reality, the emissions will be controlled through various techniques, and are likely to be significantly lower than the assume modelled maximums. The IED ELVs are the backstop limits that must be met, and will remain in the Permit, along with various other conditions set to meet specific IED requirements for EFW plant control. Continuous monitoring will be required to ensure that compliance is met at all times. The proposed EFW CHP plant is replacing an existing EFW facility, and there is a likely overall beneficial decrease in emissions within the locale, particularly taking into account heat use by Michelin and a reduction is their emissions.

5.3 Implications of the Variation on - Point Source Emissions to Surface Water and Sewer

Section 3.2 of the Supporting Technical Report (STR), dated 29 March 2018 and submitted with the variation application, discussed the abatement of point source emissions (discharges) to surface water and sewer), whilst Appendix B3 provided detail and drawings of the proposed design. The variation application was submitted prior to final design, and was an outline of the wastewater and surface water management proposals. As the commencement of construction was imminent, this required to be addressed in detail.

A Further Information Notice (FIN) was therefore served, requiring more detailed information and drawings of:

the surface water storage, and potential treatment, options for lower risk hardstanding areas;

the ultimate containment options and discharge points for the higher risk storage and delivery/uplift areas associated with the Flue Gas Treatment (FGT) and ash storage areas, chemicals and oil storage;

the fate of the process waste water, including how it is to be recirculated into the quench system and what happened to any excess;

how potentially contaminated fire-fighting water could be contained within the facility;

volumes and chemical use for treatment of the return condensate from Michelin (after supplying Michelin with heat) were also required, along with the effluent discharge route;

rainwater harvesting proposals. A new submission was received in response to the FIN which provided a lot more detail, relevant to each likely discharge, however it lacked drawings confirming the pipework, containment areas, and information on the type and size of interceptors, and the oil storage area was adjacent to the permeable paving. Following a meeting with the applicant in October 2018, a further final submission was agreed, (document 217012-MSJ-00-00-RP-D-4000-S2-P09 refers). The following is a summary description of the drainage to be implemented for the newer area of the installation:

Roof water is to be collected from the bunker house roof into a storage tank on the administration block roof, for flushing of toilets only, as it is unsuited for process water. The storage tank will have an overflow to the rainwater drainage;

Foul sewage from staff welfare facilities will discharge to the public foul sewer;

Surface water from lower risk areas within the additional installation area will have Sustainable Urban Drainage Scheme (SUDS) consisting of areas of permeable paving, discharging subsequently into a perimeter filter drain, which then will flow into a large attenuation tank of 610m3, prior to discharging to the Scottish Water surface water sewer. The discharge is subject to flow restrictions and throttled to a maximum 6.3 l/s, as a 1 in 30 year greenfield run off rate, although a rate of 3.1 l/s as the 2 year greenfield run off rate is the design level where no surcharging will occur. Additional protective measures such as silt traps, oil interceptors and emergency penstocks to prevent flow to the sewer will be included;

Surface water from ‘high risk’ areas will be contained, generally using bunds and kerbing. The surface waters from the FGT and APC lorry loading will be collected in a tank for neutralisation prior to pumping to the foul sewer. The integrally bunded oil tank will also have leak detection and tertiary containment due to its proximity to the permeable paved area, and the delivery area will have a class 1 full retention separator, enough to retain a tanker compartment load;

Fire-fighting water containment at the proposed plant will be retained within one of three designated areas. Door thresholds, and storage bunkers for the ash and waste can store contaminated water from sprinkler systems. Should any of these areas be overwhelmed, the surface water system could capture the contaminated water in the 610m3 retention tank, and the shut off valve to the site would be automatically activated;

The critical areas of the site (containing waste, chemicals etc) are all elevated which will reduce the risk from flooding. The car park area is the most vulnerable, and only

likely to flood in a 1:25 to 1:50 year event. The drainage system could potentially back up so a non-return valve is to be installed;

Process water (‘clean’) arising from boiler blowdown, condensate return and demineralised water treatment will be collected in the ‘clean water pit’ and pumped to the ash handling (quench) system for re-use, (except during the Boiler drain down when it is diverted to the cooling water basin storage area for treatment followed by discharge to foul sewer or subsequent re-use). If the pump fails, an overflow to the neutralisation basin, and on to the foul sewer, is provided;

Process water (dirty) arising from ash handling area (bunker, conveyors, loading and quench bath) will drain via the back of the bunker into the dirty water pit. Clean down water will also fall to this system. From the pit it is pumped back into the ash quench make up water system. If the pump fails, the dirty water diverts to the waste pit.

It should be noted that the proposed new EFW CHP plant has a small footprint, and there is limited scope for the installation of a more extensive SUDS due to the high groundwater levels and low permeability in the area. Water emissions from the process which may contain polluting matter will generally be re-used, or will discharge to sewer following any required neutralisation, and in compliance with the Scottish Water Consent. As the FGT uses a dry scrubbing method (detailed in the Addendum report – Appendix B1.2 – Acid Gas Abatement BAT assessment), the process does not generate the highly polluting water associated with wet scrubbing methods. Firewater containment area details are as follows:

Existing EFW Plant – 1,302m3 of containment provided in various area areas inside the buildings, including the former clinical waste pit in the Tipping hall, the screw conveyor pits in the RDF hall;

Tipping hall and waste bunkers – perimeter walls and high door thresholds with an internal storage capacity of 1,100m3;

Boiler house and turbine halls – water collects and directed to the dirty water pit and overflows only into the waste reception pit in the tipping hall;

Ash handling area – water collected here is directed to the dirty water it and overflows only to the waste reception pit in the tipping hall;

Flue Gas treatment area – perimeter wall with storage capacity of 68m3;

Surface water attenuation tank with shut off valve – capacity 610m3. Water that cannot be contained in a serious fire will be captured in this tank prior to testing an can be subsequently tankered away for suitable treatment at an off site location.

The older area of the site has existing separate drainage systems, and the run off from this area will discharge into the new surface water system, upstream of the final class 1 full retention separator and the hydro-brake. The risk will be reduced within this area once the chemicals and oil storage etc are removed during decommissioning. Foul water and drainage from higher risk areas is directed to the public sewer, and subsequently treated biologically at the sewage treatment plant at Hatton prior to discharge to the ocean. Potentially contaminated water from fire-fighting should be retained for testing prior to determining if it can be discharged to the public sewer or if it needs to be tinkered off site

The schematic details of the proposed drainage arrangements for the new area are shown in the plan below, along with the linked drainage from the existing installation. SEPA is satisfied that the arrangements for all surface-water and wastewater streams represent the best option for this site.

5.4 Implications of the Variation on - Point Source Emissions to Groundwater

There are no proposed point source emissions to groundwater. The design, operation, management and maintenance of the site will use Best Available Techniques to ensure that the risk from non point source discharges to groundwater are minimised. Standard conditions for the protection of soil and groundwater are contained in the permit that prohibit the discharge of pollutants to groundwater or soil, and also require records to be kept for the life of the permit if a spillage does occur as a result of an incident. All waste handling will be undertaken on surfaces which are impervious such as the waste reception hall floor and waste bunker, and include the bulky waste treatment that will take place in the existing plant following commissioning of the new EFW CHP Plant. Specific spillage and drainage plans already exist at the site relating to the current operation, as required by proposed Condition 7.2.2, and will be required to be updated by Condition 7.2.5 following any change to the system. Standard Condition 7.3.1 requires no emission of any pollutant to groundwater. Specific controls on the storage of liquids to current standards are contained in standard Conditions 7.2.8 and 7.2.9 to prevent fugitive emissions from any liquid with a potential polluting hazard to enter groundwaters. An isolation valve will be fitted upstream of the surface water sewer connection to allow the discharge to be stopped in case of any unforeseen incident that could affect the quality of water being discharged. This would allow the wastewater to be retained on site for treatment and/or disposal. Soil and groundwater sampling has been undertaken, prior to construction of the proposed plant to provide a site condition report to give information on the potential presence of relevant hazardous substances (RHS) prior to the operation of the new plant or any use, production or storage of any RHS. A groundwater and soil monitoring plan for the whole site must be submitted to SEPA (Conditions 2.8.6 and 7.3.7) 15 months prior to commissioning of the proposed plant, and the Boreholes constructed (Condition 2.8.7) to do this, and initial soil sampling undertaken (Condition 2.8.7) to set a specific baseline for ongoing monitoring of RHS during the lifetime of the installation across the whole installation. Monitoring will be set at a frequency based on the risk, and SEPA will review the results and assessments, and may change the frequency from time to time. See also sections 5.19 on closure and 5.20 on site condition and baseline below. SEPA is satisfied that the above arrangements will protect groundwaters.

5.5 Implications of the Variation on - Fugitive Emissions to Air

The main sources of fugitive emissions to air from the installation are, and will continue to be, dust and odour.

Odour is discussed further in section 5.7 below. Information submitted for the variation on dust control is contained in the Supporting Technical Report - sections 2.1.2 and 3.4.1. The main potential sources of dust are from the ash residues generated during the incineration process, the delivery of wastes and the delivery of raw materials (eg lime and PAC) used in the flue gas treatment processes. The combination of plant design and controls, along with good management practices will minimise the generation of dust. Bottom Ash will be quenched in waste water as it is discharged from the grate, then conveyed to the ash bunker, located internally. As it will be damp, it will not give rise to dust releases. The loading of collection vehicles will also take place within the building, further reducing any potential dust release. All powdered materials, including the PAC, calcium hydroxide and Air Pollution Control residues (APCr), will be transferred within the site using enclosed methods. The silos will have level indicators and alarms, with dust filtration and over-pressure protection. The reagents will be conveyed from the bulk tankers into the silos pneumatically via flexible hoses. The reagents will then be conveyed to the injection points pneumatically. The APCr will be conveyed pneumatically into the storage silo prior to transfer off site for final disposal by dry powder bulk tankers. The residues will discharge by a telescopic gravity discharge chute with integral vent filter units. All deliveries of reagents and removal of APCr will be supervised by site personnel in case of spillages or leaks. The Residue Management Plan required by Condition 8.1.1 of the permit variation will define ‘how each residue which is a dust, or has the potential to become a dust, shall be stored and handled in a manner designed to prevent dispersal into the environment’, as required by Condition 8.1.4.g). Dust arising from waste delivery will be minimised during delivery as all delivery vehicles will be covered and there will be a site specific speed limit to minimise suspension of dust. Dust arising during the tipping and handling, in the new EFW CHP plant tipping hall will be drawn into the combustion process through negative pressure. (See 4.3 above), and when the incineration process is not operating, will be treated in the alternative activated carbon and dust filtration system. In order to prevent odour and dust the building will be fully contained. The Tipping hall at the existing EFW plant will handle deliveries of bulky waste. Dust generation will be controlled by the containment within the building, and sweeping/cleaning as required. The existing EFW Plant stores the residues in silos, for cyclone and APC residues, and in enclosed skips for the bottom ash. This is on an impermeable surface, and was subject to BAT requirements at the time of the application. The application confirms that all areas of the facility will be hard-surfaced, both internally and externally, which reduces dust generation, and is more easily cleaned. Frequent visual

checks will be undertaken for potential dust leak, and spillages will be removed by vacuum and sweeping and water for dust suppression will be available during sweeping operations. Condition 3.5.1 requires that ‘All operations shall be carried out to prevent and minimise the potential escape of litter or dust’ ….’Litter shall be removed on a daily basis’ Good housekeeping and regular clean downs will be required, and the Operator is required to have a planned cleaning programme by way of a Hygiene Plan (Condition 4.5.6) and to record the cleaning. Different areas of the plant will require cleaning at different frequencies. The Hygiene Plan will be reviewed at inspections by SEPA to ensure that it is adequate.

5.6 Implications of the Variation on - Fugitive Emissions to Water

Section 3.5 of the Supporting Technical Report, and the updated Appendix B3, gives information on the control of fugitive emissions from the proposed new facility. The main activities of waste handling and incineration and bottom ash handling will be undertaken inside buildings and the design of the process buildings will prevent the escape of liquids from within. High volume chemical storage and oil storage will be in integrally bunded tanks, situated on hard-standing and within an area contained by a 250mm high perimeter wall with a storage capacity of 68m3. Accidental spillages will be prevented from running off the paved area, and instead by directed towards the neutralisation basin. It will be retained there prior to testing and then pumped to the foul sewer only if it is within acceptable limits. If it is not, this will have to be tankered away for treatment off site. Beyond this, should any contaminated or escaping liquid unexpectedly get onto the lower risk areas, such as the car park, where it could enter the site surface water drainage, there is a large attenuation tank and subsequent cut off valve to prevent any release to the Water Environment which could contain up to 613m3 assuming it is not already partially filled due to high rainfall. The shut off valve is connected automatically to the fire alarm system, but for other spills, will need to be operated manually. This is because the risk in this area is very low, and normally would only deal with rainfall that had drained via the SUDS permeable surfacing and perimeter drains. IBCs, drums and bags that will hold potentially polluting substances will be stored on site within appropriate containment, on impermeable surfacing, (generally within buildings) and nearby spill kits will be available. A maintenance system will require regular routine inspections of the key equipment, including the drainage, tanks and valves and the surfaces, to ensure that no leakage can impact the groundwater either directly or indirectly. The waste and IBA bunkers, and the surfaces below the residue silos and oil tank will be constructed to specific relevant British Standards to ensure their impermeability, through specific concrete quality and thickness checks. Several standard conditions within the draft permit, Schedule 7, cover the requirements to be met to protect soils and groundwater from any polluting substances. This includes the standards to be met for the structural equipment, and will require the operator to hold plans of the drainage systems, and include the inspection frequency and requirements within the maintenance system. The existing area of the site already has extensive areas of impermeable surfaces, and many of the standard requirements have been permit conditions for several years. The tipping hall at the Existing EFW Plant which will be used for the sorting of future bulky

wastes is fully enclosed, with 2 fast acting roller shutter doors (one in and one out) with a traffic light entry system. The design and techniques described in the application are consistent with the sector guidance/ BAT.

5.7 Implications of the Variation on - Odour

Information submitted for the variation on odour control is contained in the Supporting Technical Report - sections 2.1.3 and 3.6. An Odour Management plan is in place for the Existing EFW plant, but will need to be amended to take into account the additional activities and management arrangements for the proposed new EFW CHP plant. The odour abatement and containment systems and equipment will be regularly maintained as part of the planned preventative maintenance programme, and the Operator will be required to undertake at least a daily olfactory survey of the Installation, as well as procedures for investigating complaints and tracing sources of odour. Point sources of odour would be from the each EFWs incineration plant stack and the stack or vent from the odour abatement unit at each plant. The main sources of fugitive odour generation likely at the site are from the incoming wastes, and their subsequent handling and storage, and processing. The odour will arise from the tipping hall at the Existing EFW Plant, and from the tipping hall and waste bunker of the proposed new EFW CHP plant, primarily. Potential odour may also be generated at the existing EFW plant tipping hall after incineration ceases int hat plant and once waste operations to pre-treat bulky wastes start to take place there. The ashes and residues from the incineration processes at either EFW plant are unlikely to give rise to any significant odour.

5.7.1 Fugitive emissions

5.7.1.1 Proposed new EFW CHP Plant Tipping hall

Whilst recyclates and food wastes are separately collected throughout the Dundee and Angus area, it is likely that some organically contaminated waste will remain within the waste, and therefore generate some odour from the residual black bag waste that will be deposited into the waste bunker in the new EFW CHP Tipping hall. Bunker Management methods for waste mixing will be in place to prevent anaerobic conditions forming. Waste will arrive in enclosed or covered vehicles, which will minimise odour during transport. The tipping hall will be enclosed, with a single large door for ingress and egress. The door will be closed during periods when no deliveries area programmed, however, during peak periods it was anticipated that there may be periods when the deliveries are very frequent, and the door may remain open for periods beyond a single delivery.

Inlet louvres at the Tipping Hall will be provided with self-closing non-return flaps or manual closing devices, and these would be closed in the event of over-pressurisation due to wind ingress. A large single door, raised concerns at an early stage in discussions with the applicant, and further information was requested, and an advisory letter sent to them. In November 2017. A large single door would be open for longer periods, offering a larger portal and greater potential for odour to escape. Particularly a door facing south (prevailing wind is from the south-west) was a concern. To address this issue, Appendix A of the Addendum report submitted with the variation application contained additional information with regard to these concerns, and also explaining that the dimensions of the tipping hall and waste bunker were determined by the site footprint, delivery vehicle numbers and manoeuvring requirements, and the width of the perimeter road which restricts the turning space. As a result, the applicant is unable to have separate in and out doors. The Planning permission for the new plant is based on the current single large door facing south. The single door was indicated to be a fast acting door, and it was stated that “…during periods of intensive traffic movements, the doors would remain open. If a vehicle is not detected within a certain (unspecified) time, the door will close”. Odorous air arising during the waste delivery and handling activities in the Tipping Hall will be drawn from the hall, through the waste bunker, then extracted for use in the combustion process. It creates a negative pressure that will prevent the air escaping from the building and the use of air in this way is considered to be BAT. The air exchange rate will be around 2.29 x per hour from the waste storage bunker – which contains most waste and therefore the most potential for odour. This will be replaced with air from the tipping hall at up to 2.16 x per hour. These rates are set by the incineration plant design and the combustion process within it, and although lower than the SEPA Odour Guidance minimum recommendation of 3 x per hour, will still generate a negative pressure, and the odorous air will still be used. If the extraction draw off was increased, the oxygen levels in the combustion would be too high for the incineration process. A Further Information Notice (FIN) was served on the applicant, after assessing the application. This requested additional information on the controls for the louvres and doors, the storage of waste for longer periods than expected, (eg unplanned outages), an explanation of anticipated increase in vehicle movement, and an odour impact assessment with an odour contour model to demonstrate the extent of predicted odour. The response indicated that:

the louvres would be automated or interlocked with the entrance door, so door open = louvres closed;

If odour management is not effective during eg unplanned shut downs, waste will be required to be diverted away from the site, and if necessary, waste already on site will be removed;

Vehicle movements will be slightly higher than present as the availability of the incineration line is expected to be higher; Additional waste deliveries that would previously have gone to the WTS will increase deliveries to the installation, but not all will enter the new EFW CHP plant Tipping hall. The single large fast acting roller door will remain open in periods of intense traffic movements, subject to none being detected. The time will be set to ensure that the action of the doors does not create a hazard to vehicles entering or leaving due to impaired visibility or potential collision situations;

Odour dispersion modelling was undertaken to provide an odour impact assessment and contour plan of predicted odour concentrations, as required by SEPA Odour Guidance 2010. This indicated that the maximum odour concentration unit of 1.5OUE/m3 as a 98%ile of hourly averages, (for the more offensive odour types), would be met at all nearby sensitive receptors.

When the incineration process is not operating, such as during maintenance periods, the air within the bunker will be treated in the alternative off line odour abatement system which will provide an air exchange of around 2 x per hour via an activated carbon and dust filter. This in turn will continue to draw the odorous air in from the tipping hall. Again this is lower than the SEPA guidance of 3 x per hour, but will still provide a negative draw of air and the air will be treated prior to release. (See comments on Draft BAT22 below). The alternative activated carbon odour abatement system will be situated externally, on the waste bunker roof. The system is designed for short duration use during planned and unplanned outages only. The system is intended to be compact, simple to operate and maintain, energy efficient, and can be brought into use rapidly. The grade of carbon may vary as this will be determined for the types of odorous compounds present, however, the Operator has experience of using such systems at the plant in Plymouth and this will be used to inform the initial choice of carbon and final design components for the Dundee facility. It will be selected to last for a planned annual outage, plus a contingency allowance. The system comprises a centrifugal fan drawing air through a two-stage filtrations system consisting of fine filters then activated carbon cartridge type filters. The first stage removes particulates, and prevents clogging of the carbon. The filters are also kept clear by compressed air. As the organic load (VOCs) increases on the carbon filter, there will be a pressure drop, and differential pressure monitoring will be implemented so that when the carbon is saturated with VOCs, it will be removed, replaced with a new cartridge, and disposed of via the incineration process in line with sector guidance. In addition, a sample nozzle (to ‘sniff’ the outgoing air) will be provided from the outlet duct to enable daily odour checking for VOC breakout. Prior Operation Condition 3.2.9 requires the Operator to provide a written report on the methodology to be used for the monitoring of the odour at the emission point A5. A pre-commissioning condition (Condition 2.8.10) requires that smoke testing is also undertaken prior to accepting waste into the building to ensure that the air is captured from all areas of the tipping hall and bunker and pulled into both the combustion system and into the alternative odour abatement system, adequately to demonstrate the negative pressure that will prevent odour releases. Ongoing smoke testing will be required to demonstrate the efficacy of the waste storage areas by Condition 3.2.7.

The draft BAT conclusions (BAT1) require that an OMP is in place where there is expected or substantiated odour nuisance at sensitive receptors.

This already exists at the plant, but will need review to include the new EFW CHP plant. There have been sporadic complaints regarding odour in the last 6 years, usually, around 4-6 per year, and in 2018, just 3 were received by the Operator and passed on to SEPA, and all were unsubstantiated. Only 1 odour complaint has been substantiated in the last 5 years (2016), and an extensive action plan was quickly put in place to identify and address all possible sources that may have contributed to any fugitive emissions in the aging plant, and remedy them within given timescales.

Draft BAT22 required the use of Negative pressure and use of extracted air as combustion for incineration, both of which are being applied in the new EFW CHP plant. During shut-downs, the Operator will minimise waste storage and use alternative abatement.

For planned shutdowns, waste will be minimised prior to the shut down, and then will build up again over the 10 days or so prior to restart. This plant is contracted to continue to take waste, however, if the shut down runs on, the waste will be diverted away. The applicant accepted SEPAs comments with regard to possible over-pressurisation at the new EFW CHP plant Tipping hall, and has addressed these accordingly. Condition 3.2.6 requires all doors to be kept closed at all times other than during entry and exit of vehicles to contain the air.

5.7.1.2 The Fluidised bed EFW Plant.

This plant is currently used for incineration, and has an existing odour abatement plant, with an ELV of 6,000 OUE/m3.

Once incineration at this plant ceases, the Tipping hall will be used for delivery, storage and pre-treatment of bulky wastes from transfer stations, to remove recyclates and prepare the residual waste for incineration. This is unlikely to contain significant levels of wastes that could generate odour, and the activities will be contained within the building, and the doors closed. This activity is currently undertaken on the adjacent Waste Transfer Station, and in an environment that is not contained and this will improve the potential for any fugitive odour release. Fast acting in and out doors with traffic light entry on this facility will be retained and used for this storage and sorting activity, and the loading of the vehicles to take the waste into the incineration plant will also take place within this contained environment. The personnel doors have closing devices. It is unlikely that odour will be an issue from this part of operation, particularly with the fast acting roller doors closed, except during entry and exit of vehicles and personnel.

5.7.2 Point Source Emissions (Moving Grate EFW CHP Plant)

There will be a point source emission from the incineration process at the installation, which will be dispersed via a 90m main stack. During normal operation the air from the waste tipping hall and storage bunker in the new EFW CHP plant will be extracted to the combustion chamber of the incinerator. During the incineration process the odorous compounds will be destroyed and then discharged as treated flue gases to atmosphere through the stack. During such times when the incineration process is not operational (i.e. planned shut-down) the air from the waste tipping hall and waste storage bunker will be extracted via an alternative Activated Carbon Unit (ACU) which will be located on the roof of the of the bunker building with the exhaust vent around 8.3m above the roof, (and around 3.2m above the roof of the boiler house).

The emission from the ACU will have an ELV in place of 3,000 OUE/m3, that is 50% lower than that from the existing operation. A permit condition (3.2.8) will require a record of all times this unit operates, and a further condition (3.2.9) requires the submission of a method to be used to monitor the emission during use.

During periods where the process has closed due to unforeseen circumstances, the alternative ACU may also be used if it is likely that the unplanned closure may take days rather than hours to remedy.

5.8 Implications of the Variation on - Management

5.8.1 Management

Section 4 of the SRT provides information on the Integrated Management Systems (IMS) and Environmental Management System (EMS) to be used at the site to ensure effective management of the environmental impact from the Installation. The site currently has an IMS in place, introduced by the previous Operator, that includes extensive environmental elements. The current operator is looking to adapt and update this into their own systems, and achieve the relevant ISO accreditations, as implementation of accredited IMS and EMS will ensure that key pollution prevention and control procedures are in place. It gives a formal, structured approach to environmental management, and is considered BAT. The proposed new EFW CHP plant will be operated and maintained under the new systems from the outset and will include a Management of Maintenance procedure with the aim of achieving ‘world class performance in maintenance, reliability and environmental protection’. Their proposed Management of Maintenance procedures will include a preventative maintenance strategy, defining the maintenance schedule of all operating plant. This will be based on the Operation and Maintenance (O&M) Manual that will be provided by the technical suppliers of the incineration plant and the ancilliary plant and monitoring equipment. A copy of the IMS Manual from the Plymouth site, also operated as part of the MVV group, indicates the Maintenance objectives, and includes optimising the operation of the plant through short and long term planning, to improve plant availability, and to operate a policy of continual improvement using root cause analysis. The company uses the industry standard methods for identifying machinery, parts and other infrastructure for programming into the management systems for maintenance, inspections etc. The existing EFW plant already has a preventative maintenance strategy and programme in place, and this will remain unchanged for this plant by the Operator at this stage. The company hopes to gain the site specific ISO accreditation within the first year of operation, including ISO 9001:2008, ISO 14001:2004 and OHSAS18001:2007. ISO14001 includes criteria to be met that includes an effective environmental management system. OHSAS18001 is an occupational Health and Safety Series – a British Standard that enables the Operator to demonstrate that they have a system in place for occupational health and safety. These standards are currently met at the groups Plymouth and Ridham sites, and supporting documentation to demonstrate this was supplied as part of the application in Appendix C1.2 of the SRT. This indicates the Operators commitment to meeting high standards of environmental management and compliance throughout MVVs integrated management systems. The EMS will include procedures to ensure compliance, and confirm which post holder has specific responsibilities for environmental aspects such as monitoring. Monitoring results are already reported internally and to SEPA. There will be annual audits of the IMS, and the findings will be reported to SEPA. MEB has provided a copy of their Environmental Policy in the application (c1.1 of the SRT), and the management techniques discussed above indicate their commitment to continual improvement.

The approach to Management of the facility is consistent with the requirements of BAT

5.8.2 Training

Every position at the Permitted Installation will be covered by a specific job description that clarifies the required skills and competencies expected, as well as the responsibilities and reporting requirements. The training needs identified for all staff are already in place for the existing operations, as technical competence and staffing has had to be demonstrated already for the waste incineration activities already being carried out at this site. In addition, standard permit Conditions (section 2.12) will continue to ensure that this is met, and that the facility is adequately supervised by a competent person. Section 4.1 of the SRT gives further information on the development of the training matrix and how a gap analysis is carried out for any new member of staff so the training can be prioritised appropriately. Training information is retained on ‘Carval’, the HR system that forms part of the sites IMS. It is likely that many of the staff at the existing EFW plant will migrate over to the new facility. Key personnel will be determined nearer the time when the plant is closer to becoming operational. The Technically Competent person at the site, who is the current Site Manager, is likely to be able to continue to provide the supervisory Technical Competence during the transition. Additional staff will be recruited in advance, and trained for their roles to ensure they are familiar with the new plant in advance of start up. Contractors will have any required technical competencies considered during the assessment of control of contractors procedures on an ad hoc basis. This also takes into account environmental risks. The approach to training is consistent with BAT.

5.8.3 Fit & Proper Person

Operation of a ‘Specified Waste Management Activity’ requires that checks are made to ensure the facility will be operated by a ‘fit and proper person’. “Specified waste management activity” is defined in the PPC 2012 Regulations as meaning an activity comprising – “ … (b) the disposal of waste falling within Sections 5.3, 5.4 or 5.6 of the Part of that Schedule [Schedule 1] or (c) the disposal or recovery of waste in a waste incineration installation,”. The existing facility already includes the disposal of waste in a waste incineration Installation and is therefore already considered to be a Specified Waste Management Activity. The ‘fit and proper person’ test was applied previously during the transfer process and the first variation following the transfer to MEB. The elements of satisfying Regulation 18 in relation to fit and proper persons are: Reg18 (4) (a) – a person is not a fit and proper person if it appears to SEPA that – the person or a relevant person has been convicted of a relevant offence.

SEPA has already confirmed that neither MEB, nor any other relevant persons in terms of Regulation 18(4)(a) has a relevant conviction. A standard permit condition (2.12.15) requires that SEPA is notified should this change.

Reg18 (4) (c) – a person is not a fit and proper person if it appears to SEPA that – the person and all staff engaged in carrying out the activity will not be provided with adequate professional development and training.

SEPA has already determined that a system is in place at the existing EFW Installation which is delivering adequate training and professional development to personnel operating and supervising the activities. In addition, the programme will be further developed to incorporate the new plant. Standard permit condition 2.12.1 requires that any new staff will also have to be provided with adequate training prior to undertaking the role.

Reg18 (4) (c) – a person is not a fit and proper person if it appears to SEPA that – the management of such an activity will not be in the hands of a technically competent person

SEPA has already determined that the Installation is supervised by a Technically Competent person, and there is no change proposed.

The Installation is already operated by a fit and proper person, and there is no change likely in the foreseeable future. This meets BAT requirements.

5.8.4 Accidents

(See also section 5.16 below). An accident risk assessment has been provided in Appendix B5 of the STR, which identifies the likelihood and potential consequences of accidents, and also identifies what actions are to be taken to prevent and mitigate against these risks. An Operational Incident Management process is already in place, which defines the requirements for reporting incidents, identifying corrective action, recording and subsequent investigation and implementing and recording the corrective actions to prevent future similar accidents. The existing training also includes specific aspects relating to accidents such as spillage prevention, and various equipment is already located on the site relating to spillage prevention. The existing EFW plant already has an emergency preparedness response procedure in place, as well as corrective and preventative actions, and specific plans such as winterisation of the plant. These will be replaced or updated, or used to inform the new site specific documentation development as part of the Installations IMS/EMS. A site drainage plan for the site is kept at the gate house in case it is required for emergency decisions. This will need to be updated once the new EFW CHP plant construction is complete. This approach is consistent with BAT.

5.9 Implications of the Variation on - Raw Materials

The Raw Materials selection and substitution criteria for materials to be used at the new facility are discussed in the STR – Section 5.1, and also in the Site condition and Baseline report for assessment of the risk to groundwaters and soil, and by means of the BAT assessments for the Acid gas Abatement and the NOx abatement selection (see section 5.10).

Other than the waste feed from residual MSW and third party Commercial and Industrial waste (“C & I waste”) the main raw materials that will be processed at the Facility are summarised below together with details of the proposed storage and delivery arrangements: Low-sulphur gas oil for the auxiliary burners This is stored in an above-ground, double-walled, storage tank of 60m3capacity, and will be delivered to site in bulk tankers. The bund will have a capacity of 110% of the stored volume, and there will be additional tertiary containment. Approximately 108 tonnes/annum will be used. Urea solution (40%) This is for use in the SNCR (NOx reduction) system. It will be stored in an above-ground, integrally bunded, storage tank of 50m3 capacity, and will be delivered to site in bulk tankers. The tank will be bunded to the minimum required 110% of the volume of the solution and will be contained on an impermeable area with tertiary containment, with surface drainage diverted to the neutralisation facility and the foul sewer in the event that there is a spill or leakage. Expected use is around 400 tonnes/annum. Calcium hydroxide (ie Lime) This is one of a range of chemicals used for the dry scrubbing of acid gases. It will be delivered in bulk, offloaded by pneumatic lines and stored in an above ground 130m3 storage silo. The exhaust air generated during the filling operation will be filtered using fabric filters, located on the top of the silo. Expected use will be 1920 tonnes/annum. Powdered Activated Carbon (PAC) This is used to assist in the removal of volatile heavy metals and organic pollutants such as dioxins. It will also be delivered to site in bulk and stored in an above ground 50m3 silo, also with fabric filters for the venting during filling and additional monitoring to prevent over-pressurisation. Approximately 64 tonnes/annum will be used. All tanks and silos will have level monitors and alarms connected to the SCADA systems and alarms generated will sound in both the tank/silo location and also in the control room. The existing EFW has a fully bunded tank for the storage of the auxiliary fuel oil, and the chemicals used are contained in silos for dry chemicals, or bunded tanks for liquids. The PAC is currently stored in IBCs. The older silos at this EFW plant have had recent retrospective upgrades to filter displaced air due to over-pressurisation. The new systems at the new EFW CHP plant are designed to have this in place from the outset.

Demineralised water plant regeneration chemicals (35% hydrochloric acid (HCl) and 30% sodium hydroxide (NaOH)) are already used in the demineralisation plant that serves the existing EFW plant, and will serve the new EFW CHP, to regenerate the plant ion exchange resins. HCl usage is expected to be around 24 tonnes/annum and NaOH usage around 7 tonnes/annum. Both reagents are be delivered to the facility by road tanker, and both will be stored in bunded 20m3 storage tanks located internally within the demineralisation plant. The bunds have a capacity of 110% of the stored volume.

Boiler treatment chemicals such as corrosion inhibitors and oxygen scavengers, will be used to dose the boiler to prevent boiler tube corrosion. These will be stored in separate and suitably contained tanks within bunded areas inside the demineralisation plant. There is a blind ‘capture’ pit on the delivery apron at the demineralisation plant to prevent any escape of these chemicals during deliveries, which are expected to be annual.

Other lubricating oils will be stored in purpose built containment units throughout the relevant parts of the plant where they are required for use.

Calibration gases are held within their individual cylinders in storage cases, prior to transfer into the CEMS analyser unit at the existing EFW plant. It is proposed to utilise the same CEMS analyser type and a similar unit for the new EFW CHP plant. In terms of management, techniques and procedures, this will remain similar to before.

Waste will be contained in the impermeable waste bunker and residues will be stored in the ash bunker and APCr silos. See sections 5.13 and 5.14 below.

5.10 Implications of the Variation on - Raw Materials Selection

Raw materials selection are discussed in section 5.1 of the STR submitted with the application, and a list supplied. Procedures for the selection and review of the raw material will be incorporated into the IMS (see section on Management below), and will be reviewed against the sector guidance. The methods of containment are described in table 1 of section 5.2 of the STR, along with the proposed volumes and expected annual usage. Substitution criteria are listed in table 2 of the report. Support fuel will be natural gas. The main raw materials to be used for abatement are those considered to be BAT in the sector guidance (see below for details of specific raw materials used in abatement). PAC has been selected as the absorbent for dioxins/ heavy metal adsorption from flue gases and is accepted as this is a standard raw material used in the EfW Sector for this purpose. The applicant has confirmed that selection of other raw materials will take into consideration environmental aspects, such as any biocides and dispersants/surfactants will be selected to have high biodegradability; and low mercury NaOH will be used; Alkaline reagents and PAC will have low concentrations of persistent pollutants such as metals.

5.10.1 NOx abatement at the new Moving Grate EFW CHP plant

The BAT assessment for NOx abatement is detailed in detailed in Appendix B1.1 of the Addendum report submitted with the application. The assessment is summarised here, but discussed in more detail in section 5.21.2 of this Decision Document NOx can be reduced by good primary combustion control but requires additional secondary measures. The BAT assessment looked at these in more detail, and considered impacts on/from air quality; photo-chemical ozone creation potential (POCP); raw materials; global warming potential (GWP) based on energy consumption, the wastes arising from each process and the capital and ongoing costs. The following techniques were considered:

Primary NOx abatement only – which involves a well mixed turbulent primary combustion chamber and a secondary combustion chamber with secondary air injection and flue gas recirculation (FGR);

Selective Non-catalytic Reduction (“SNCR”) – a reagent, usually ammonia in solution or urea (either as dry prills or in solution) is injected into the combustion chamber to react with the NOx. It takes place at temperatures between 850ºC and 950ºC, and reduces NOx emissions by chemically reducing the NOx to nitrogen and water;

Selective Catalytic Reduction (“SCR”) - This technique involves the injection of ammonia or urea into the flue gases immediately upstream of a reactor vessel where the flue gas is then passed over a catalyst, usually some form of mesh at temperatures between 250ºC and 300ºC, and usually located at the end of the gas cleaning process.

Flue Gas Recirculation optimises reagent use, although it increases maintenance requirements, and is unlikely to meet the IED ELVs in isolation. However, it does reduce NOx by around 10-20% and will be combined with SNCR techniques. Urea is less hazardous than ammonia but the N2O emissions may be higher than those released using Ammonia. Urea in solution has been selected as overall, taking all environmental aspects into consideration, it represented BAT for this facility, although the differences between this and ammonia were marginal.

5.10.2 Acid gases abatement at the new Moving Grate EFW CHP plant

The BAT assessment for the Acid Gas Abatement is detailed in Appendix B1.2 of the Addendum report submitted with the application. The assessment is summarised here, but discussed in more detail in section 5.21.2 of this Decision Document. The assessment considered air quality; photo-chemical ozone creation potential (POCP); raw materials; global warming potential (GWP), and the wastes arising from the following techniques.

wet scrubbing;

semi-dry scrubbing;

dry scrubbing using hydrated lime; and

dry scrubbing using sodium bicarbonate. Wet scrubbing was discounted immediately due to the high volume of hazardous process water generated, and because it reduces the power efficiency of the plant, and similarly, semi-dry scrubbing was discounted early. Dry scrubbing using calcium hydroxide (ie Lime) was selected as it represented BAT and the hazardous residues can be disposed of within Scotland without requiring further treatment. Sodium bicarbonate, although less hazardous for handling and use, produces residues that would require export from Scotland for treatment and subsequent disposal.

5.10.3 Other

Standard Condition 2.6.1 of the proposed Permit Variation requires a systematic assessment of the raw material consumption and emissions associated with the Permitted Activities to be undertaken over a 4 year period, and data collected annually. The purpose of the assessment is to identify methods of reducing raw material consumption, waste and emissions. Projects will be identified and specified timescales to implement these are also part of the standard Condition. This is already contained in the current permit, however, as all schedules in the current permit will be deleted and replaced, this clarifies that the Operator is already working to this system. Routine review of raw materials selected for use is proposed in Section 5.1 of the STR submitted with the application, and SEPA is satisfied that BAT has been applied in the selection and ongoing use of raw materials for the proposed EFW CHP facility.

5.11 Implications of the Variation on - Waste Minimisation Requirements

Waste minimisation is discussed in section 5.3 of the STR submitted with the application. This indicates that waste minimisation audits will be undertaken in the first 12 months of operation and repeated at 2 yearly intervals. The standard permit conditions 2.6.1 already in the permit requires that this is reviewed and reported on a 4 yearly basis to SEPA. Minimisation techniques such as early leak detection through the pro-active maintenance and inspection of plant will be undertaken. The aim of the facility is to reduce waste going to landfill, with energy recovery, so waste reduction is more limited than with other industries and activities. Optimisation of the consumption of chemicals (urea, PAC, calcium hydroxide, etc) that will be utilised in the process will take place during the hot commissioning period, and subject to regular review. Reagent re-circulation is adopted in the FGR (see 5.10.1 above) and the APC residue return so that the consumption of fresh calcium hydroxide is minimised as far as possible. Residues from the process will also be required to be minimised, as required by standard conditions 8.1.1, 8.1.2 and 8.1.4c) and where possible, recycled or re-used. At present, the bottom ash is re-used under a Waste Management Licence exemption. The APRc goes off site for disposal. The Operator has been actively looking at other potential re-uses, and has been developing relationships with a number of operators looking to re-use the ashes. In Scotland this is a developing market, and the amount of these wastes will increase sharply with other new sites coming on line in 2019. SEPA has also been looking at allowing limited use of IBA in aggregate and this is a developing area.

5.12 Implications of the Variation on - Water Use

The water use at the facility will be for general site use, including wash-down and welfare, and supplying the demineralisation plant, which generates the boiler make-up water. This will primarily come from the mains potable water supply, with additional water taken from the Dichty Water under the abstraction licence (CAR/L/1004581) under the Controlled Activities Regulations. There will also be rainwater harvesting from the bunker house roof, to supply water for the toilet facilities inside the building. The mains water is already supplied to the site and metered by Scottish Water. Since the construction of the Existing EFW, the demineralisation plant was replaced with a more efficient one which has a larger throughput. The demineralisation plant provides up to 23m3/hr of treated water. Other water-efficient techniques to be used include closed loop systems, dry scrubbing techniques for acid gas emissions abatement, the reuse of wastewater from boiler blow-down, boiler water sampling and the demineralised treatment process as make up water for the quenching of the hot ashes, as per sector guidance BAT considerations. Additionally, some will be re-used for humidification of the FGR, which increase efficiency through reaction and reduces reagent use.

A water efficiency audit will be undertaken at the end of the first year of operation, and a review of proposals identified for further water savings will be incorporated into the water efficiency objectives and subsequent Improvement Plan. In addition, whilst this is not part of the PPC permitted activities, water saving techniques such as spray taps, duel flush toilets etc will be adopted through the new facilities, and rain water harvesting of roof water from the bunker house roof will be used to flush the administrative block toilets. The above approach is consistent with BAT.

5.13 Implications of the Variation on - Waste Handling

5.13.1 Waste inputs handling

The information on waste inputs handling is provided in Sections 2.1.1, 5.2 and 6.1 of the SRT, submitted with the variation application. The waste to be accepted at the new plant is generally of the same type as the existing plant, ie pre-sorted residual waste (usually pre-sorted and segregated) from the residential properties and residual wastes from third party commercial and industrial (C&I) contracts. Much of the C&I waste will be delivered to the adjacent council run Baldovie waste transfer station for prior sorting before bulk transfer to the Permitted Installation. The majority of waste is pre-authorised and the vehicles are permitted in an automated tab system already in use at the site. Pre-authorisation details will include the waste categories (including the European Waste Classification (EWC) code). Where a different vehicle is used, eg in the event of a breakdown, there are other special procedures in place. Pre-acceptance testing is not generally necessary for municipal waste, as it is covered by a Local Authority derogation from SEPA, which also covers companies acting on behalf of the Local Authority. The C&I contracts that are in place with a small number of third parties include pre-acceptance procedures, which have been verified with these third parties. The Operator has applied for additional non-hazardous waste types to be included in the variation request. Some of the original list could not be accepted, as they were either hazardous or liquid wastes, and the removal of these has been agreed with the Operator during a meeting about the draft permit. Traffic is controlled via automatic barriers, and the delivery vehicles must go via the weighbridges both on the way into the site, and on the way out. The IED requires the operator to collect information about the waste to verify compliance with the permitted categories of waste, including vehicle registrations, where the waste comes from, etc. Any unexpected waste deliveries arriving will be directed to wait for authorisation. If this cannot be obtained, the vehicle will be turned away. The acceptance procedures comply with the IED requirements. Power generation and heat energy will be recovered from the burning of these wastes in the new plant, which differs from the existing plant where only power generation took place. The proposed EFW CHP plant will be authorised to take the following wastes:

EWC index number (6 figure code)

Description

02 Wastes from Agriculture, Horticulture, Aquaculture, Forestry, Hunting

& Fishing, Food Preparation & Processing

02 01 Wastes from agriculture, horticulture, aquaculture, forestry, hunting & fishing

02 01 02 Animal-tissue waste

02 01 03 Plant-tissue waste

02 01 04 Waste plastics (except packaging)

02 01 07 Wastes from forestry

02 01 09 Agrochemical waste other than those mentioned in 02 01 08

02 01 99 Wastes not otherwise specified

02 02 Wastes from the preparation and processing of meat, fish & other foods of animal origin

02 02 02 Animal-tissue waste

02 02 03 Materials unsuitable for consumption or processing

02 02 99 Wastes not otherwise specified

02 03 Wastes from fruit, vegetables, cereals, edible oils, cocoa, coffee, tea and tobacco preparation & processing; conserve production; yeast & yeast extract production, molasses preparation & fermentation

02 03 04 Materials unsuitable for consumption or processing

02 03 99 Wastes not otherwise specified

02 05 Wastes from the dairy products industry

02 05 01 Materials unsuitable for consumption or processing

02 06 Wastes from the baking and confectionery industry

02 06 01 Materials unsuitable for consumption or processing

02 06 02 Wastes from preserving agents

02 07 Wastes from the production of alcoholic and non-alcoholic

beverages (except coffee, tea & cocoa)

02 07 01 Wastes from washing, cleaning and mechanical reduction of raw materials

02 07 02 Wastes from spirits distillation

02 07 04 Materials unsuitable for consumption or processing

03 Wastes from Wood Processing and the Production of Panels and Furniture, Pulp, Paper and Cardboard

03 01 Wastes from Wood Processing and the Production of Panels and Furniture

03 01 01 waste bark and cork

03 01 05 sawdust, shavings, cuttings, wood, particle board and veneer other than those mentioned in 03 01 04 03 01 99 Wastes not otherwise specified

03 03 Wastes from Pulp, Paper and Cardboard production and processing

03 03 01 waste bark and wood

03 03 07 mechanically separated rejects from pulping of waste paper and cardboard

03 03 08 wastes from sorting of paper and cardboard destined for recycling

03 03 10

Fibre rejects fibre-, filler- and coating-sludges from mechanical separation

03 03 99 Wastes not otherwise specified

04

Wastes from the Leather, Fur and Textile Industries

04 01 Wastes from the Leather and Fur Industry

04 01 08 Waste tanned leather (blue sheetings, shavings, cuttings, buffing dust) containing chromium

04 01 09 Wastes from dressing and finishing

04 01 99 Wastes not otherwise specified

04 02 Wastes from the Textile Industry

EWC index number (6 figure code)

Description

04 02 09 wastes from composite materials (impregnated textile, elastomer, plastomer)

04 02 10 organic matter from natural products (for example grease, wax)

04 02 21 Wastes from unprocessed textile fibres

04 02 22 Wastes from processed textile fibres

07

Wastes from Organic Chemical Processes

07 02

Wastes from the MFSU of plastics, synthetic rubber, and man-made fibres

07 02 13

13 Waste plastic

07 02 17 Wastes containing silicones other than those mentioned in 07 02 16

07 02 99 Wastes not otherwise specified

09

Wastes from the Photographic Industry

09 01 Wastes from the Photographic Industry

09 01 07 photographic film and paper containing silver or silver compounds

09 01 08 photographic film and paper free of silver or silver compounds

15

Waste Packaging; absorbents, wiping cloths, filter materials and protective clothing not otherwise specified.

15 01 Packaging (including separately collected municipal packaging waste only where not capable of being recycled)

15 01 01 Paper and cardboard packaging

15 01 02 Plastic packaging

15 01 03 Wooden packaging

15 01 04 Metallic packaging

15 01 05 Composite packaging

15 01 06 Mixed packaging

15 01 09 Textile packaging

15 02 Absorbents, wiping cloths, filter materials and protective clothing

15 02 03 Absorbents, filter materials, wiping cloths and protective clothing other than those mentioned in 15 02 02 16 Wastes not otherwise specified in the list

16 01 End of Life Vehicles from different means of transport (including off road machinery) and wastes from dismantling end-of-life vehicles and vehicle maintenance (except 13, 14, 16 06 and 16 08)

16 01 19 Plastic

17 Construction and Demolition Wastes (Including excavated soil from contaminated sites) 17 02 Wood Glass and Plastic

17 02 01

01 Wood

17 02 03 Plastic

17 09 Other Construction and Demolition Wastes

17 09 04

Mixed construction and demolition wastes other than those mentioned in 17 09 01, 17 09 02 and 17 09 03

19 Wastes from Waste Management Facilities, off-site Waste Water Treatment Plants & Preparation of Water intended for Human Consumption / Industrial Use

19 02 Wastes from physico/chemical treatments of waste (including dechromatation, decyanidation, neutralisation)

19 02 03 Premixed wastes composed only of non-hazardous wastes

19 02 10 Combustible wastes other than those mentioned in 19 02 08 and 19 02 09

19 02 99 Wastes not otherwise specified

19 05 Wastes from aerobic treatment of solid wastes

19 05 01 Non-composted fraction of municipal and similar wastes

EWC index number (6 figure code)

Description

19 05 02 Non-composted fraction of animal and vegetable waste

19 05 03 Off-specification compost

19 05 99 Wastes not otherwise specified

19 06 wastes from anaerobic treatment of waste

19 06 04 digestate from anaerobic treatment of municipal waste

19 06 06 digestate from anaerobic treatment of animal and vegetable waste

19 06 99 Wastes not otherwise specified

19 08 wastes from waste water treatment plants not otherwise specified

19 08 01 screenings

19 08 12 Sludges from biological treatment of industrial waste water other than those mentioned in 19 08 11 19 08 99 Wastes not otherwise specified

19 09 wastes from the preparation of water intended for human consumption or water for industrial use 19 09 04 Spent activated carbon

19 10 wastes from shredding of metal-containing wastes

19 10 04 fluff-light fraction and dust other than those mentioned in 19 10 03

19 10 06 other fractions other than those mentioned in 19 10 05

19 12 Wastes from the mechanical treatment of waste (for example sorting, crushing, compacting, pelletising) not otherwise specified

19 12 01 Paper and cardboard

19 12 04 Plastic and rubber

19 12 07 Wood other than that mentioned in 19 12 06

19 12 08 Textiles

19 12 09 Minerals (for example sand, stones)

19 12 10 Combustible waste (refuse derived fuel)

19 12 12 other wastes (including mixtures of materials) from mechanical treatment of wastes other than those mentioned in 19 12 11

20 Municipal Wastes (Household and Similar Commercial, Industrial and Institutional Wastes) including separately collected fractions

20 01

Separately Collected Fractions (only where not capable of being recycled)

20 01 01 Paper and cardboard

20 01 08 Biodegradable food waste

20 01 10 Clothes

20 01 11 Textiles

20 01 25 edible oil and fat

20 01 38 Wood other than that mentioned in 20 01 37

20 01 39 Plastics

20 01 99 Other fractions not otherwise specified

20 02 Garden and Park Wastes (including cemetery wastes)

20 02 01 Biodegradable waste

20 02 03 Other non-biodegradable waste

20 03 Other Municipal Wastes

20 03 01 Mixed municipal waste

20 03 02 Waste from markets

20 03 03 Street sweeping residues

20 03 04 Street cleaning residues

20 03 06 Waste from sewage cleaning

20 03 07 Bulky waste

20 03 99 Municipal wastes not otherwise specified

Wastes coming onto the site are delivered by road, in covered or enclosed vehicles such as rear end loaders, articulated bulk haulage vehicles, hook loaders etc. Every delivery vehicle will be directed to drive onto the first (IN) weighbridge initially, once the barrier is raised. At this point the weighbridge operator will enter the vehicle registration information to check it is a pre-authorised vehicle on the list (such as a regular Council delivery vehicle), then check for oral confirmation of the load. If the authorisation is confirmed, the weighbridge operator will record the load on the weighbridge database and direct the driver to the appropriate bay of the 4 bays in the new tipping hall. The exiting vehicles leave via a second weighbridge, where the lorry weight is also recorded. A load weight can then be calculated automatically. This checking and recording system is already in use at the site, although the current tipping hall reception activity differs. In some circumstances, drivers may be required to tip into a designated quarantine area for inspection of the waste, as some wastes will not be allowed such as: clinical wastes, PVC or metal doors/Window frames, liquid wastes, gas containers, animal carcasses, car parts, large waste electrical and electronic equipment (WEEE), large plastic or steel pipes, construction and demolition wastes (in excess of 5% by weight), baths, large ropes and cabling, etc. If the load contains non-conforming waste, that waste will be removed, and if appropriate shredded in the Tipping hall of the Fluidised bed EFW plant to prepare it for combustion. Otherwise, it will be weighed and secured, prior to export for off-site treatment or disposal. The waste is then picked up by an overhead grab crane and fed into the feed hopper. From there it drops onto the feed chute below, which leads onto the Moving grate. The feed chute is separated from the hopper by a flap gate, which can isolate feed during start up/shut down and any maintenance. This flap also prevents any risk from combustion gases escaping from the grate feed mechanism, and it is also triggered when waste levels become too low or too high. Any non-conforming or bulky waste tipped into the waste storage bunker, is monitored by the control room operatives, and they will be able to direct the crane operators to remove the items The waste bunker can holder around 5000m3, and this equates to approximately 2000-2500 tonnes of waste, or approximately 10 days storage of the contract waste from the two Councils. This is considered sufficient to accommodate a normal planned outage, however, if the outage is longer, the waste will be diverted to a contingency delivery point. No C&I waste is accepted during planned outages, and the third parties are notified in advance, but it will be stopped without notice if the outage is unplanned. Waste Duty of Care Records will be kept for all waste accepted onto and sent out from the site.

5.13.2 Waste Residues

The design of the proposed EFW CHP plant will segregate the handling and storage of IBA from APCr, and this is discussed in section 6 of the STR. Other wastes such as non-confirming wastes removed during the checks will be recorded and removed, and where practicable, separated prior to disposal.

Tests will be carried out, as required by Article 53 (1) of the IED to establish the physical and chemical characteristics and polluting potential to determine the appropriate disposal or recycling routes. This is required to demonstrate that the residues are minimised in their amount and harmfulness. The Operator proposes to use the sampling protocol Environmental Services Association (ESA) for the sampling and testing of IBA. Analysis will also be required to comply with the current WM3 Technical Guidance to demonstrate if the waste is hazardous or not. Hazardous waste will require to be consigned using Special Waste Consignment Notes and non-hazardous waste will be transferred using waste Duty of Care transfer notes. The current operation already has a similar system in place, and similar record keeping. The only difference is that the IBA may have slightly different characteristics to the existing Bottom Ash due to the different type of incineration technology used. The IBA will consist of approximately 24% by weight of the input wastes, equating to around 26,400 tonnes/annum. It will be made up of materials such as glass, ceramics, brick and some metals from composite waste materials. Following discharge from the end of the grate into the Quench bath, it will be transferred via conveyor to the concrete ash bunker where the water will drain off (although up to 20% by weight is retained in the ash). The bunker can hold around 9 days or 500m3 of waste. A grab crane will load it internally from the bunker into the collection vehicle for off-site removal. The building is ventilated to prevent gases building up. The IBA is to be tested, as per the ESA protocol, and then it will stored, at another site (William Tracey, a hazardous waste treatment site at Dunniflats, East Ayrshire) until it is confirmed whether it is hazardous or not, at least during the commissioning period, as the Operators site in Dundee is not large enough to store this volume of ash. Once it has been confirmed that the IBA is non-hazardous, it is proposed to send the IBA to DJ Laings in Petterden, Angus, for further processing to remove metals and re-use of the remaining materials for restoration and landscaping purposes under a Waste Management Licence or exemption, for at least 3 years, or to use it in line with the new Position Statement on Incinerator Bottom Ash Aggregate (IBAA). The current IBA already goes to DJ Laings. The Operator is currently investigating other re-use options with various companies. Boiler ash from the second and third passes of the incineration plant will be discharged into hoppers and conveyed to the Quench, along with the IBA. The Air Pollution Control (APC) residues which comprise fly-ash, the reaction products from the acid gas neutralisation process, and activated carbon with absorbed metals and organic compounds, are classified as absolute hazardous waste. They equate to around 3.5% of the waste inputs, or 3850 tonnes/annum. Some of the APCr is recirculated and reinjected into the flue gas to improve reagent reuse. The remainder will be transported from the bag filter hoppers of the flue gas treatment plant to the APCr storage silo, which has a maximum storage capacity of 250m3 or around 4 days of storage.

The silo is vented through particulate filters situated on the top of the silo and has level measurement within which reports to the control room. This area has contained drainage, where potential fugitive emissions can be retained and treated prior to discharge to the foul sewer. The APCr will be removed from site via enclosed discharge chutes into dry powder bulk tankers to a suitably permitted waste treatment or disposal site.

During the lorry filling operation, displaced air will vent back to the silo, so that any releases to atmosphere will pass through the silo particulate filters.

It is proposed to send the APCr, as a hazardous waste, to William Tracey in Ayrshire for neutralisation and subsequent disposal. This is the same arrangement as the residues from as the existing plant. The disposal site is currently looking at treatment options for this material to re-use some of the constituents.

All rejected feedstock will be extracted and sent off site for recycling, treatment or disposal at a more suitable site. MEB intend to undertake regular reviews and audits of the options available for waste recovery and disposal to ensure that the waste is dealt with in an appropriate manner, and that potential re-use or recovery is maximised. This approach to residue management is consistent with BAT.

5.14 Implications of the Variation on - Waste Recovery or Disposal

As the purpose of the plant is for waste incineration, there are less opportunities for beneficial re-use of products or raw materials than many other industries. The recovery aspects tend to be limited to energy recovery (See section 5.15 below), and some water re-use techniques (see section 5.12 above) and potential re-use of at least some of the residues produced by the process, (see sections 5.11 and 5.13 above).

5.15 Implications of the Variation on - Energy

Energy is discussed in Section 8 of the STR Appendix F of the Addendum Report, and a separate Heat and Power Plan (HPP) all submitted with the application documentation. There were contradictions between some of the figures provided between these documents, and following a FIN request, the whole STR section, including a new HPP, was revised and resubmitted in the FIN response, received on 31 July 2018, along with an explanation regarding the basis of the figures. Thermal Treatment of Waste Guidelines 2014 SEPA’s Thermal Treatment of Waste Guidelines (TTWG) issued in 2009, were updated in March 2014, and promote that waste treatment is in line with the waste management hierarchy to maximise the beneficial re-use, recycling and recovery or treatment of waste. Waste should be recycled as far as practicable, however, where the residual waste cannot be recycled, for example, if it is too contaminated etc, then best practice is recover the heat and electrical energy during incineration. Appendix 1 of the TTWG sets energy efficiency targets for the recovery of electrical and heat energy from the incineration (combustion) process. These are adopted from the Quality Assurance for Combined Heat and Power (CHPQA) standard, published by DEFRA in defining how energy recovery efficiencies are calculated. An energy efficiency target of 20% (gross calorific value basis) is required at start-up by the TTWG for all new waste thermal treatment plants treating more than 70,000 t/annum. An energy efficiency target of 20% (gross calorific value basis) is required at start-up by the TTWG for all new waste thermal treatment plants treating more than 70,000 t/annum. This is met (see table 5.15.1 below)

Heat & Power Plan (HPP) For this installation the waste will be incinerated (combusted), and the heat used to generate high pressure steam which will drive a steam turbine, to generate electricity for export to the National Grid from the incineration boiler system. It is also proposed to extract steam from the turbine and feed it to the adjacent Michelin factory** for use, as heat, in the tyre manufacturing process. The EFW CHP Plant will have the potential to extract more heat in future should a heat network distribution system be progressed or other nearby users be identified. SEPA usually sets an indicative time period of five to seven years from commencement of the activity following cessation of commissioning, until the heat plan is met. Several factors will influence the development of the heat plan, including potential users. SEPA require the proposed EFW CHP to meet the predicted efficiency target within 7 years from cessation of commissioning, as with the potential removal of Michelin the alternatives are likely to take time to set up. This may include supplying heat to a local energy supply company (ESCo), as Dundee Council has a Sustainability Heating Strategy to cover the next 10 years, that includes setting an ESCo up as a medium term objective. A number of potential heat users have already been looked at as part of the DCC strategy and the MEB plant could potentially also tap into this. The HPP plan will be subject to regular review and management through standard conditions in the permit. The existing EFW plant already provides power to the National Grid, however, it does not have the infrastructure to provide heat, and cannot meet the TTWG Efficiency targets without a very significant upgrade. It will be shut down after the new EFW CHP is commissioned, and there will be no parallel generation from both plants, (the capacity of the network connection to the National Grid is insufficient to accept power from both plants simultaneously). Information required by Annex 2 of TTWG 2014 on the facility technology, description of waste to be treated and its energy value, heat & Power plan (heat users and heat demand), and the diagram showing the CHQPA system boundary and the permit boundary, in accordance with Annex 3 of TTWG (see Appendix F1.1 of Addendum report), was provided. The response to the FIN (Appendix B of the 31 July 2018 submission) indicates that the proposed new EFW CHP will have an initial efficiency of 20.7% (based on gross calorific value) in power only mode, and the predicted efficiency and QI values from the report are replicated below taken from the initial application and showing a recent update in red. The predicted targets must be met within 7 years from the cessation of commissioning. __________ (**NB The contract between the proposed EFW CHP and Michelin is in place, and the infrastructure to transfer the steam has already been commissioned, however, a recent unexpected announcement indicates that Michelin will now not be operating at this location by mid-2020. The plant however, is still contracted to provide heat to the Michelin plant and this has not changed. The Michelin plant may yet attract other industry, particularly with the available heat for potential production etc, and at this stage the current plans are still progressing, so SEPA is required to proceed with the determination. MEB have confirmed in writing to SEPA that they are in discussions with DCC to progress possible District Heating plans or similar, and this is expected to produce a final plan in mid 2019).

Table 5.15.1: Energy Recovery Efficiency Targets from SEPA TTWG 2014

Description Target Predicted energy efficiency level once connected to National Grid

Predicted energy efficiency once connected to National Grid and Michelin

Predicted maximum potential energy efficiency level in full CHP mode

Initial operation at start-up on cessation of commissioning Note 1

20% (gross calorific value basis) equivalent energy recovery efficiency

20.7% 22.9% Note 2

Not required Not required

To be achieved within 7 years following cessation of commissioning

QI value OR Indicative Efficiency

93

Not applicable

84 88.7 Note 2

Not provided 90.7 Note 2

35% Not applicable

37.6% 37.2% gross

Note 2

59.6% 44.5% gross

Note 2 Notes

1. Cessation of Commissioning means that point when a plant has been commissioned and is thermally treating waste.

2. Figures as given in the application/FIN are in black and figures in red are a recent submission now that design and procurement are finalised

Whether the new EFW CHP plant supplies heat to the adjacent Michelin plant only, or ultimately to other users via a heat network, the Indicative efficiency will meet the TTWG target of 35%. (See above). The most recent figures indicate that there are some changes in the predictions due to a higher output power and a lower parasitic load in the calculations and a reduction in the maximum steam output giving a lower maximum potential efficiency level. Waste Framework Directive ‘Recovery’ Plants The Waste Framework Directive defines new incinerators which can recover energy efficiently as ‘Recovery’ operations (rather than disposal operations). To demonstrate this, incinerators must be capable of meeting an ‘R1’ energy efficiency benchmark of 0.65. Appendix B1 of the FIN provides the R1 calculations in CHP mode, and B2 provides them in power only mode. Calculations carried out indicate that during start-up with export of electricity only the R1 calculated energy efficiency will be 0.66 (or 0.74 following climate change correction). With the export of heat energy to Michelin, it is anticipated that this will increase to 0.78 or 0.87 following climate change correction, although this may now change if the heat is used elsewhere. Operation to meet the required QI values of the TTWG should also satisfy the target energy efficiency values for achieving status as an ‘R1’ recovery plant. Under the PPC 2012 regulations compliance with R1 values is not required but does indicate efficient energy recovery.

Other Energy Benchmarks Electrical energy – waste incineration guidance1 suggests that where electricity only is generated then for each 100,000 tonnes of MSW incinerated between 5 to 8MW of electricity should be generated. At start-up of the facility electricity only may be generated at 10.16MWe (for 110,000t MSW incinerated, equating to 9.6MWe per 100,000t MSW incinerated which is slightly above guideline expectations, however, if the electricity used by the plant is taken into account, this leave 8.70MWe as the net electrical output, or 7.9MW. The Specific Energy Production (SEP) was calculated as 0.47MWhe/t when the facility is in CHP mode, or 0.63 when it is in power only mode, and the Operator intends to review this annually. Additional reference to energy efficiency operations, maintenance, and techniques are made in the SRT, with the structure and plant being designed to be as energy efficient as possible and plant will be optimised during commissioning stages to stabilise the process which will maintain steady operation, helping to optimise energy recovery. Waste heat from the process that cannot be used for power/steam production directly, will be utilised for the pre-heating of boiler feed water and combustion air. Flue gas re-circulation (used for NOx reduction) will have the added benefit of increasing plant energy efficiency, Energy Efficiency Directive The Energy Efficiency Directive (EED) requires applicants of specific processes to carry out a Cost Benefit Assessment (CBA) as part of the application for a permit to determine whether waste heat can be utilised within a radius of 15km from the installation. SEPA consider that this requirement has been met through the HPP submission and that the accompanying SEPA duty to ensure that the proposed use of the heat will be realised is met through the inclusion of the HPP Standard Conditions into the Permit. In this case, the applicant already has an agreement with the adjacent site (Michelin, which may change – see notes above above) and a Permit condition requires that the heat will be utilised within 7 years of plant commissioning. SEPA is satisfied that the proposals meet the minimum targets and therefore meets BAT. It will significantly improve on recovery over the existing plant.

5.16 Implications of the Variation for - Accidents and their Consequences

Accidents are discussed in sections 4.2 and 9, and Appendix B5 of the STR, and additional information on Fire protection and Firewater Management is available in the Addendum report (Appendix C) submitted with the application, and the containment and drainage aspects in the Further Information Notice response received on 31 August. The Integrated Management Systems (IMS) has a specific Level 2 document (OS.HSE.02.01) on the Environmental aspects at the Plymouth site, and a site specific one is to be developed for the proposed new EFW CHP facility. An accident plan is in place for

1 Guidelines for the Incineration of waste and fuel manufactured from waste, Section 2.7.3 part 9

the existing plant, however, this will be replaced in time to reflect the current Operators systems and standards. The objective of the document is to outline the activities, products and services that may impact on the environment, and to ensure planning is undertaken so in the event that there is an occurrence that could have any environmental impact that relevant controls and mitigation are in place. This method considers specific criteria and how it will comply with legal requirements. This requires the generation of an accident risk assessment. An accident risk assessment has been provided as part of the application, identifying the likelihood and consequences of accidents that could impact on the environment or human health. Many of these are also safety issues, and will be considered further during detailed design stages. The plant will not have any substances above the thresholds identified in the Control of Major Accident Hazards (COMAH) Regulations, which would require regular inspection between the HSE and SEPA in addition to the normal PPC inspection regime. The risks are presented as potential events, and the pathways and receptors considered. An assessment is then undertaken to assign an overall hazard scoring, and controls and mitigation are identified to reduce the risk levels (scores) to the point where the residual risk is low. The main areas examined include:

Material delivery (raw materials and waste);

Waste storage;

Raw material storage;

EFW combustion process;

Steam system/power generation;

Abatement system;

Ash handling and disposal;

General site issues; and other potential hazards

A full HAZOP study will consider the planning, design, build and operational aspects and consider the accident and safety risks, taking into account issues such as:

The use of emergency shutdown systems and electrical trips;

Gas, fume, dust and liquid detection systems;

Firefighting systems;

Containment systems; and

Emergency escape.

Redundancy has been considered, and provision of eg duty and standby plant etc made available; critical spares will be kept on site, with other spares available on site as required or through call in contractual arrangements.

Standard conditions 2.5.7 and 2.5.8 of the draft variation require the preparation, implementation and maintenance of an Incident Prevention and Management Plan, with a 2 yearly review. This is required to be reviewed prior to commissioning of the proposed EFW CHP. There is an existing plant for the current EFW, and this has been inspected from time to time. The new one will be inspected once it is available. One of the most significant issues at any facility handling waste is uncontrolled fires, and the management and containment of any fire-fighting water, which may be contaminated. This is discussed further below

Water is provided for fire-fighting purposes, and information has been provided confirming the types and extent of the firefighting and detection equipment in use throughout the plant. This confirms that these meet current industry best practice (including the Insurance industry’s ACE Technical Risks Engineering Information Bulletin – Guidance document).

The existing firewater storage tank will be used for firefighting at either the existing EFW plant or the proposed new EFW CHP plant, and as these are separate buildings, the tank is adequately sized for dealing with a fire at either one of the buildings. Diesel pumps and electric pumps are both in place for transfer of the water, and a duty/standby system operates. The pumps are regularly tested, in line with insurance requirements. The facility has full emergency services access around the entire perimeter of the site. The design of the plant means that areas are compartmentalised, using perimeter bunding, suitable floor drainage falls, gulleys and sumps to ensure that any contaminated fire water is retained and directed into the waste pit. Each area has its own fire protection systems which operate independently, and therefore minimise the amount of water required for any potential fire-fighting. Containment by area is fully described, and plans provided for each area, along with the surface water drainage containment information for the whole site in the documentation. Calculations have been provided to confirm the minimum storage requirements have been met to contain the maximum predicted wastewater arisings from a fire. This meets the IED requirements in Article 46(5) to prevent the accidental release of substances into soil, surface waters and groundwaters. This is a requirement of standard Condition 7.3.1 in the variation. At least 1778m3 volume of contaminated water within the new plant must be able to be contained, as required by condition 7.2.1(d), in addition to the potential containment around the existing plant, calculated as 1302m3. The routing of the contained waters is described in Appendix B3 of the STR –updated report on the surface and foul water design, along with the plans. October 2018 version 9. Firewater containment summary: a) New EFW CHP Plant

the tipping hall and waste bunkers area – water will be directed into the waste reception pit with a capacity of 1100m3. This has been designed as an impermeable concrete vessel and will be capable of storing contaminated water even if some waste is already present.

the separate boiler house area directs water to fall to the dirty water pit, and it would then flow to the waste reception pit;

the ash handling area waters would also collect to the dirty water pit and onto the waste reception pit;

the flue gas treatment area has a perimeter wall, capable of retaining 68m3, and any discharge would flow into the neutralisation tank, which leads to the foul sewer ultimately. This can be prevented by shutting down the pump;

The surface water area has an underground attenuation tank that can be ‘sacrificed’ to capture up to 610m3 in the event that the other containment becomes inundated;

b) Existing EFW Plant

The existing plant also has perimeter wall upstanding and a drain across the door that leads to the foul sewer, preventing the potential entry of contaminated liquids to groundwaters. Up to 1302m3 can be contained within this plant. The existing external

areas all have tertiary kerbing and bunding to prevent run off. These will be retained until decommissioning of the existing plant, and all potential contaminants removed.

Excess waste will be diverted away from the site in the event that the incineration process is not available unexpectedly or for a longer period than anticipated. The fire-fighting foam or gel to be used has not yet been finalised for the new area but the Operator has confirmed that this will be selected based on relevant pollution prevention guidance. The above is considered to meet BAT guidance for the prevention of fire and the management of contaminated run-off from fires.

5.17 Implications of the Variation for - Noise

Section 10 of the SRT, Section 5 and Appendix D of the Emissions and Impact Assessment, and Appendix I of the Addendum report submitted with the application discuss noise. The Operator has indicated in the STR that the new EFW CHP Plant will be designed to minimise operational noise through selection of low noise plant items, noisy equipment will be mounted inside closed buildings, doors will only be opened for the transit of vehicles and staff (except the main tipping hall door which was the subject of further discussion and there is a condition in the draft (Condition 3.2.6) requiring all doors to be closed other than during access or egress. The STR also indicates larger openings on the façade such as ventilation openings will be avoided or suitably attenuated, and wall and roof cladding construction will be designed to minimise noise breakout from within the buildings. Vehicles will have to reverse into the tipping bays within the Tipping hall at the new EFW CHP plant and at the storage area for ash loading (located on the north of the building). Potential significant noise sources have been identified as: Internal sources: o Waste tipping hall and bunker area; o Boiler house; o Turbine hall; External sources: o ACC fans; o Chimney; ID fan; o Exhaust steam pipe; and HGV vehicle movements The STR indicates that equipment that may lead to vibration such as the turbine generator, compressors and fans will be mounted so as to minimise the transfer of vibration energy to the building structure. As part of their IMS, the Operator intends to provide a Noise and Vibration Management Plan – this is required by Condition 3.1.2 of the draft variation. The Operator has recognised that there are additional and necessary noise source activities during commissioning, such as steam blowing and testing of safety systems, and indicate that they will take steps such as using suitable temporary silencers during such activities, and give prior notification to SEPA and the local community. The current plant sits on an industrial estate, with other waste facilities to the west and several other small and medium businesses, a scrap yard to the south, and the Michelin factory to the east. A main road sits to the north between the estate and the housing to the north. To the south, the Dichty burn sits beyond the scrapyard, and beyond that is a street with mixed industry then beyond this, is an extensive residential area.

There have been just 2 isolated complaints about noise from the Installation over the last 3 years. The first was unsubstantiated; the investigation of the second concluded it was probably due to both boilers starting up at the same time, with steam bypassing the turbine, before pressure was sufficient to switch it to the turbine. This is a normal if infrequent operation. However, the new EFW CHP is a different operation with different noise sources and in different locations, and located nearer housing to the south. A noise study was carried out prior to the application to establish the impact from the existing EFW Plant (Report number M132032/03 by Muller-BBM). This study provided a baseline of noise monitoring emissions from the existing EFW plant at 7 noise sensitive receptors (known as Points of Interest or POIs) selected around the proposed EFW CHP plant to represent the residential receptors that would be most exposed to impacts from noise emissions. The receptors were located at: o Strathaven Terrace; o Britannia Drive; o Montpellier Gardens; o Hawick Drive; o (E,F,G) 3 locations on Balunie Drive. Using acoustic data based on the Plymouth EFW plant, (which is a similar design although much larger, and operated by the same group, and situated less than 100m from the nearest residential receptor), a model was developed to predict the likely noise at the POIs. The level of predicted noise emission from each main building/element were calculated, using various assumptions about building materials, facades, doors and other openings, as well as noise transmission losses, based on operational experience. The modelled predicted noise levels from the new EFW CHP plant and compared them to the measured background levels (90% values; LA90,T), which includes the noise from the current operation. The model results provided in the Emissions and Impact Assessment report, showed that the noise levels from the new EFW CHP plant would be below the measured background LA90, T values recorded during the survey both in the daytime and at night-time. It also showed that noise levels at all POIs from the proposed EFW CHP facility would be below the maximum acceptable background levels of 50dB for daytime (07:00 to 23:00 hours) and 45dB for night time, (23:00 to 07:00 hours) identified in the horizontal guidance IPPC H3. The information in the Application documents indicated the various equipment applications in use, and where they may be deployed. It was quite generic, so a Further Information Notice (FIN) was served that required additional information on how noise and or vibration would be designed out or minimised from each area of the plant where noise could be generated, taking into account energy, raw material use, and waste generation. It was requested to link the specific measures to a model and assess the options. It was also requested that tonal noise and low frequency noise and vibration was included, as well as noise associated with any steam venting. A further submission was provided as Appendix 6 of the response to the FIN Report number M139854/01 by Muller-BBM). Whilst this provided more specific modelled information and additional detail, it did not demonstrate options for minimising noise further by considering different combinations of equipment to see what gave the best result, taking into account energy use, etc. It re-confirmed earlier predictions that maximum acceptable background noise levels are unlikely to be exceeded.

The model did not considered the impact from the potential decommissioning and removal of parts of the existing EFW plant, and how this could increase noise levels particularly to the north of the plant. It looked at only the normal mode of operation, and had not considered start up and shut down when steam venting is likely to be occurring until the turbine is bypassed, or when the alternative odour abatement plant and associated fans are operating. The night time information did not take into account the 4m height (used to assess noise at bedroom levels and considered best practice). As a result of this, an additional prior operating condition (2.8.12) has been placed into the draft variation requiring a further BAT assessment to be provided (9 months before the planned burning of fuel or waste) to take into account operating under different conditions (other than normal operation), to assess the noise at bedroom levels, and to consider different options to minimise the noise from the individual sources and undertake a sensitivity analysis at the POIs. This is to try to ensure that options that may minimise noise further, without excessive cost and energy use etc are not discounted simply because the first option has indicated noise below the limits and below the measured levels. Standard conditions are contained within the draft permit variation. 3.1.1 requires a systematic assessment of impact on noise sensitive receptors to be undertaken at least every 4 years, or whenever there is a replacement, installation or relocation on equipment that could contribute to impact, however, this is changed to every 2 years following SEPA experience at other PPC sites including sites involved in combustion. Standard condition 3.1.2 requires a Noise and Vibration Monitoring plan, which will be reviewed at least every 4 years or whenever there is a change that could impact on noise emissions. New condition 3.1.4 requires that noise emissions from the Permitted Installation may not contain Audible Tonal Noise as defined in BS4142, at any residential receptor. This will give SEPA a means of measuring the noise if necessary and taking action should there be an unexpected issue. This condition is inserted following SEPA experience at other PPC sites including sites involved in combustion. New condition 3.1.5 requires that validation modelling will be undertaken within 3 months of the new EFW CHP plant becoming operational. Standard Condition 3.1.6 now limits the times that waste may be accepted. The existing permit has no time restrictions however, it was considered that given the location, there should be some restriction, as is common at many PPC and waste sites. The first draft variation proposed waste acceptance only between 0700 and 1900 Monday to Friday; 0700 to 1200 on Saturdays, and no deliveries on a Sunday. However, the Operator disagreed with this change although they do not generally operate over night, except during ‘emergencies’ (eg if the Local Authorities they have contacts with require an urgent pick up of fly-tipped waste to be deposited). Documentation submitted to Dundee City Council to obtain Planning permission by the applicant included an Environmental Statement which indicates they will be open between 0700 to 2000 hours daily. This was considered to be a reasonable alternative, to keep noise impact to a minimum, given that the large door at the large south-facing tipping hall door will potentially allow noise emissions when open and the new plant is situated closer to the southern residences. The sound power level (in dB) at the maximum load was used as the basis for the response to the FIN, and this indicates that the level at the Tipping hall has only been considered

against the hours of 07:00 to 20:00 hours as it is assumed that the main door to the tipping hall at the new EFW CHP plant is closed from 20:00 to 07:00. It is possible that numerous vehicles will be ‘lined up’ along the southern perimeter entry road to make deliveries. These deliveries have a higher noise output than those picking up the ash slag etc. It has been assumed that these operate between 07:00 and 23:00 hours. It did not seem reasonable to extend this into the hours accepted as “night-time”, without appropriate modelling based on noise surveys at this time of day/night. There is also the potential issue of the roller door itself – depending on the material it is made of and the motors used. The Operator has since indicated that this is also not acceptable and wishes to extend the hours to 0600 to 2200 hrs daily in order to service a proposed new contract with the Local Authority that includes extending the collection rounds to reduce vehicle numbers and costs. This was initially refused, for the reasons above. The Operator then indicated that the existing plant has the unrestricted hours at present, and they could service the new contract in this plant which although it has south facing doors, it will have the new building (already under construction) between it and the southern residences. It was verbally agreed to change the hours for accepting waste only from 31 December 2019. This allows the Operator time to undertake additional noise monitoring and modelling and submit a variation to SEPA to extend the hours beyond the hours in the draft variation and they will be able to service the new contract from 01 April 2019. During inspection the performance of the facility in terms of noise emissions and effectiveness of noise management techniques will be assessed against the Noise and Vibration Management Plan.

5.18 Implications of the Variation for - Monitoring

Monitoring is discussed in section 11 of the SRT submitted with the application.

5.18.1 Emissions to Air monitoring

Standard permit template condition 6.1.3 requires the Operator to implement the requirements of the IED in terms of the type of monitoring to be carried out the monitoring method or standard to be used, the parameters to be monitored, the frequency of such monitoring and the associated emission limits at the specified locations, along with the monitoring required for correction (see below). Continuous monitoring The Operator already monitors the emissions to air from the 2 flues in the existing plant to the relevant British Standard, using a Continuous Emissions Monitoring System (CEMS) equipment certificated to the Environment Agency’s (“EA’s”) Monitoring Certification (“MCERTS”) Scheme, and as required by the existing permit conditions. Routine automatic calibration is undertaken, and there is a standby unit available to take over if either of the 2 separate duty CEMS fail. For the proposed new EFW CHP, monitoring will also be undertaken in the stack using a CEMS, certificated to the EA’s MCERTS Scheme, with a duplicate CEMS system on a duty/standby basis so that the monitoring can continue almost seamlessly if the duty CEMS fails. The CEMS will be powered via a UPS so that in the event of any power failure to the

plant the emissions monitoring will continue during any safe-shut down operation, also fed by the UPS and the 400V AC emergency low-sulphur diesel motor-generator. Remote operation is also available (via the technology provider) even without the process operator interface, for safety purposes. The chimney monitoring facilities will be designed to meet the EA M1 guidance on sampling requirement for stack emissions monitoring and M2 guidance on the monitoring of stack emissions to air. Monitoring will be undertaken during hot commissioning, during any start-up and shut down, and during normal operation. The CEMS will interface with a digital process control system for the operation and monitoring of the plant from the central control room. As required by IED Annex VI, Part 6, the following parameters will be able to be monitored continuously via the CEMS: oxides of nitrogen (NOx), carbon monoxide, (CO) particulates, total organic carbon (VOCs) hydrogen chloride, (HCl) hydrogen fluoride (HF), and sulphur dioxide (SO2) In addition, ammonia and nitrous oxide will be required to be monitored by the permit, in advance of the BAT conclusions being published. HF is difficult to monitor continuously, and expensive, and HCl can be used as a substitution in line with the IED Annex VI – Part 6 paragraph 2.3, provided that periodic HF monitoring is undertaken. The monitoring of the exhaust gases is required by the permit for water vapour, gas temperature, oxygen content, pressure, velocity and flow is required by the permit to enable the correction of the raw emissions concentrations to standard conditions to compare with permitted emission limits. Continuous monitoring of key process parameters will be undertaken for temperature and oxygen will also take place to demonstrate that the temperature remains above 850oC in the secondary combustion chamber, and that there is sufficient oxygen available for oxidation. The proposed CEMs will meet the requirements of the quality standard BS EN 14181:2004, which requires that the following is met:

the QAL 1 uncertainty requirements (prior to installation);

the QAL 2 quality assurance requirements (after installation and at three-yearly intervals thereafter); and

the QAL 3 quality assurance requirements (zero and span checks during operation); and an annual surveillance test (“AST”) quality assurance requirements which is similar to a mini QAL2. .

Corrected ELV results will be fed to the control room, and triggers and alarms set for action by operational staff, or if above ELVs due to any disturbance of the flue gas abatement or monitoring, or below temperature, automatic interlocks will prevent waste feed. Periodic monitoring

This will be undertaken at stacks A1, A2 and once it is commissioning, stack A3, using extractive methods. The Operator will continue to use UKAS accredited independent test houses using equipment accredited to MCERTS standards. Table 6.2 of the permit states the substances, frequency of testing, reference period and monitoring standards/methods to be used. The same parameters will be monitored as for the continuous monitoring, and in addition, Heavy metals, nitrous oxide, dioxins and furans, dioxin-like polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs), will all require to be monitored. The number of runs specified for periodic monitoring in Table 6.2 other than dioxins and furans and dioxin-like PCBs, is three with the average over the three runs being the reported value for compliance purposes. This is consistent with the proposed frequency for testing in the draft Waste Incineration BREF (page 681).

In addition to the standard pollutants which are required to be monitored by IED, additional monitoring requirements have also been specified for the following pollutants:

Ammonia – due to potential for generation from the Selective Non-Catalytic Reduction using injection of urea, therefore continuous monitoring requirements have been specified in the Permit. These are consistent with the frequency specified in the S5.01 and the Draft WI BREF BATC 5 and is consistent with monitoring already carried out at other operating UK EfW sites.

Nitrous oxide – N2O emissions are known to increase when SNCR is used particularly when urea is used as the reagent rather than ammonia. The Draft WI BREF BATC 5 specified an annual frequency for monitoring [Ref. 15.8.1.1 Draft WI BREF D1 BATC for monitoring requirements and BAT-AELs], therefore monitoring requirements have been specified in the Permit. Monitoring has been specified to be quarterly for the first year of operation consistent with other periodic monitoring frequencies for the first year, and then annually.

Dioxin-like PCBs and PAHs – monitoring is a requirement of Regulation 29(2) of PPC 2012 which specifies that where dioxins and furans are referred to in IED for waste incineration plants, specifically in Chapter IV and Annex VI, this is to be read as if it is substituted with the words “dioxins, furans, dioxin-like polychlorinated PCBs and PAHs. Monitoring requirements for these pollutants are therefore specified in Table 6.2 of the draft permit.

Species to be monitored

Dioxin-like PCBs – The standard list already specified in Table 6.2 of the Sector Template IED-T-14 has been used in the Draft Permit. PAHs – The standard list for PAHs specified in footnote 2 to Table 6.2 in Schedule 6 of IED-T-14 is to be reviewed by the Waste Incineration Delivery Group/permitting team because the currently listed PAHs do not cover all 16 of the historically monitored PAHs. PPC Regulation 29(2) does not specify which PAHs require to be monitored and this is not detailed in either the Environment Agency Monitoring Technical Guidance Note M2, or the Draft Waste Incineration BREF D1 where the only PAH monitoring required is for benzo(a) pyrene on an annual basis. The list of 16 PAHs identified in Section 2.10.1 of the draft (Indicative BAT item 11) of the UK Incinerator Sector Guidance Note IPPC S5.01 Issue 1 [Ref. 5.18.1-2] has therefore been used instead to update the Table 6.2 footnote 2. This is consistent with the suite of 16 PAHs commonly monitored by Stack Monitoring Contractors for existing

operational Energy from Waste facilities in Scotland (Records checked for MEB, Dundee and RWE Markinch Biomass Plant, Glenrothes) and is commonly known as the DEFRA 16 list.

The frequency specified for monitoring dioxin-like PCBs and PAHs in Table 6.2 is the same

as for dioxins and furans, as recommended in Section 2.10.1 of S5.01 (Indicative BAT 10) and implied by PPC Regulation 29(2).

In Table 6.2 Footnote 2 has been changed to refer to the list of 16 PAHs recommended for monitoring in the Sector Guidance s5.01. An update to the WI template IED-T-14 will be progressed to make this change for all sites. The monitoring will be quarterly for the first full year of operation, and then every 6 months. Daily visual monitoring of the site will check for visible emissions including smoke from the stacks.

5.18.2 Monitoring to the water environment/Sewer

The most contaminated water from the process will be re-used in the ash quench facility, and as there is no wet scrubber system proposed, there will be no special monitoring requirements set by the Permit (which is similar to the existing situation). However, as the ‘clean’ waste water from the boiler blow down, condensate drains, feedwater pump drains and the boiler water sampling equipment that is sent to the neutralisation tank discharges to the public sewer, the controls set by Scottish Water must be achieved and there will be continuous measurement of pH, temperature and flow using equipment certified to MCERTS standards. These will be verified during inspection to ensure this is in line with the Scottish Water Licence.

5.18.3 Monitoring to the groundwaters/soils

This is not specified, by the Operator other than to confirm that when any other sampling and analysis is required, it will be undertaken by an independent testing organisations that is accredited to MCERTS. Prior operating Condition 2.8.6 requires submission of the soil and groundwater monitoring plan, as required by standard permit Condition 7.3.7. It must include the methodology and frequency, of sampling. Prior operating Condition 2.8.7 requires the construction of the boreholes, once locations have been agreed following assessment. Sampling must also be undertaken prior to burning fuel or waste as part of commissioning, and an assessment submitted under prior operating Condition 2.8.9

5.18.4 Monitoring of waste residues

This will be undertaken as described in section 5.13.2 above.

5.18.5 Other monitoring

Monitoring for dust, noise and odour will be undertaken in line with the specific monitoring plans, and recorded on the Shift logs. Abnormal emissions will be recorded and reported. No environmental monitoring beyond the boundary on the vegetation is proposed, as this is a site where there is an existing EFW and a prior EFW, and is quite industrial. It would be difficult to determine which of the plants have led to any pollutants that may be present on the local soils and vegetation, and as access to areas where third party permission is required can also be onerous and not always in the same place it is not considered that this would be beneficial at this time. SEPA is satisfied that BAT has been applied for the monitoring requirements of all emissions

5.19 Implications of the Variation for - Closure

The Existing EFW Plant has an over-arching de-commissioning plan in place, as required by the existing permit. Standard Conditions relating to the decommissioning plan, and a requirement to maintain it, review it and follow it are contained in Conditions 2.11.1 to 2.11.4 of the variation draft. Condition 2.11.4 requires that it is reviewed at least every 4 years, or whenever there is a substantial change, so this will require a review once the new EFW CHP plant reaches the cessation of commissioning. This review will also need to provide more detail on the decommissioning of the existing EFW plant activities. Site Closure is also discussed in section 12 of the SRT provided with the application, and details of containment are provided in the sections 5.4 and 5.6 above. The applicant has designed the proposed EFW CHP facility to adequately contain the substances that will be used to minimise fugitive emissions to prevent their escape. Any incidents that have, or could lead in future to fugitive emissions to the soil or groundwaters will be recorded, and standard permit Condition 7.3.2 requires that this is retained up to permit surrender.

5.20 Implications of the Variation for - Site Condition Report (and baseline report)

This is discussed in the site condition and baseline report dated 29 March 2018, and submitted with the application, and an Additional Risk Assessment Report (No 3362/01 Issue 6, by Terraconsult, submitted later, but forming part of the application documentation. The focus of the information was for the proposed ‘new’ area to be added to the current Installation boundary. It initially lacked some detail with regard to the Relevant Hazardous Substances (RHS) that could potentially be contained in the return condensate from Michelin, the wastes, process waste-water and the residues. In addition, as detailed drawings were not available at that time, further information was required on the containment features including joint construction. A clear statement of condition was not provided. Following a FIN request, the subsequent response, detailed in Appendix 7 of the ‘Response to SEPA’ document, received on 31 August, gave the required information, including a clear statement of condition.

The current incineration site was not subject to the same requirements as the proposed new area as it was constructed and commenced operation before the changes in the PPC2012 regulations that required such detailed investigation and the setting of Baseline information, however, some information was available to inform the overall site condition. The area for the proposed EFW CHP was previously used for storage of aggregate etc. and has previously not had any industrial activity directly on it, but reference is made to various nearby activities including the construction of the first incineration plant to the north, the Michelin tyre factory to the east, the scrapyard to the south, and the gradual build up of the industrial estate to the west and north. A full history of land use has been investigated as part of the Site Condition Report. The site required clearing and preparing, with soil removal and retention for later bunding work. A ground investigation was undertaken in 2016 to assist in assessing the risk associated with contaminants already present. The boreholes (new and existing) and trial pit locations used in the investigation are shown below.

The majority of the site will be covered by buildings and areas of impermeable hardstanding, which will prevent future ingress by any RHS to be used at the site. Substances already present have been assessed to ensure that there is no increase in their concentration in future. Standard Condition 7.3.6 contained in the draft permit requires ongoing regular monitoring of specific compounds in the soils and groundwater to confirm that there is no deterioration and that the use of any RHS at the site has not led to any emissions into the ground.

The frequency for monitoring and substances chosen, indicated in Tables 7.1 and 7.2, has been determined based on the findings of the Site Condition and Baseline Report, however, this will be reviewed after the first assessment, as construction, particularly within the new site is likely to have changed the potential contamination concentrations or removed areas of contamination. In order to undertake the required monitoring, additional new boreholes must be constructed before the new plant starts hot commissioning and before any chemicals and other substances brought onto the new area. New Conditions 2.8.5 and 2.8.6 requires that these are completed, construction logs submitted and the first assessment submitted to SEPA prior to the commissioning. Boreholes require time for settlement prior to undertaking actual samples – usually a few weeks, so leaving construction until the plant is ready for commissioning is not recommended.

5.21 Implications of the Variation for - Consideration of BAT

The incineration of waste in a new installation requires that the installation meets current and relevant technical guidance, which is based on the IPPC BAT reference document (BREF) on best available techniques for waste incineration, In the UK, the main technical guidance is contained in The waste incineration BREF and UK technical guidance note s5.01; guidance for the incineration of waste and fuel manufactured from or including waste. The key considerations for BAT are around the type of plant (furnace), choice of flue gas treatment, and meeting compliance with the requirements laid out under the IED, with particular regard to emissions.

5.21.1 Technology options appraisal

The options appraisal was submitted as part of the application, in the Addendum report as Appendix B1.3. This looked at three broad types of incineration, namely, incineration (combustion), pyrolysis and gasification. The latter two are considered to be Advanced Thermal Treatment (ATT) methods, as they use lower temperatures. However, these were both discounted early as unproven technologies in the UK. 5 such plants were identified in the UK in 2013, and all have so far been operationally unreliable at a commercial scale for treating residual MSW and most have since closed. The Operator has no direct experience of these technologies. Of the incineration technologies, the report considered 3 options, which were:-

Moving grate;

Oscillating Kiln; and

Fluidised bed.

A comparison of performance looked at proven success, general advantages and disadvantages, scale of operation, availability (including maintenance periods), emissions, energy efficiency and combustion efficiency. It also had to consider that operational availability is key to the provision of the heat for Michelin. Following this assessment, it was concluded that moving grate represented BAT for the replacement EFW for Dundee.

5.21.2 Flue gas abatement choice

The choices for the treatment of the flue gases are summarised in sections 5.10.1 and 5.10.2 above relating to the choice of techniques as it impacts on the raw materials. In addition the BAT assessment is more fully described below. NOx The BAT assessment for NOx abatement is detailed in detailed in Appendix B1.1 of the Addendum report submitted with the application. Although NOx can be reduced by good primary combustion control (well mixed air flows in a turbulent combustion chamber), it is not a suitable option on its own, and additional secondary measures are required. The BAT assessment looks at these in more detail. The NOx assessment considered air quality; photo-chemical ozone creation potential (POCP); raw materials; global warming potential (GWP) based on energy consumption, the wastes arising from each process and the capital and ongoing costs. The following three techniques were considered:

Selective Non-catalytic Reduction (“SNCR”) – with ammonia. This technique involves the injection of ammonia in an evaporating solution, or urea as either dry prills or in solution into the combustion chamber. It takes place at temperatures between 850ºC and 950ºC, and reduces NOx emissions by chemically reducing the NOx to nitrogen and water;

Selective Non-catalytic Reduction (“SNCR”) – with urea as either dry prills or in solution into the combustion chamber. It also takes place at temperatures between 850ºC and 950ºC, and reduces NOx emissions by chemically reducing the NOx to nitrogen and water; and

Selective Catalytic Reduction (“SCR”) - This technique involves the injection of ammonia or urea into the flue gases immediately upstream of a reactor vessel where the flue gas is passed over a catalyst, usually some form of mesh at temperatures between 250ºC and 300ºC, and usually located at the end of the gas cleaning process.

All options considered can meet ELVs and will not cause an impact on air quality. Flue Gas Recirculation reduces NOx by around 10-20% as it reduces the amount of oxygen (from the fresh air) in the secondary air injection at the combustion chamber. This increases boiler efficiency, and also reduces the amount of reagent required. FGR requires greater maintenance, and has a higher energy demand. This was not looked at separately, but will be used here to optimise reagent usage.

Whilst SCR can achieve greater NOx reduction compared to SNCR techniques, it has little reduction in the ground-level concentrations. Photochemical Ozone Creation Potential (POCP) is lower for SCR as it is directly proportional to NOx, but the SCRs higher abatement cost per unit of POCP does not justify the additional cost. Global Warming Potential (GWP) is lower for SNCR due to the high level of additional heating required by SCR to maintain the catalyst in optimum conditions, and SCR generates spent catalyst, which is hazardous waste and cannot be recovered. Application of these techniques is described in the Waste Incineration BREF (pg 350-356) as resulting in 24h average emissions of NOx of:

SCR - 15 to 100mg/Nm3 (sector guidance suggests emissions of below 70mg/Nm3 are achieved).

SNCR - 80 to 180mg/Nm3 SNCR with urea was selected as it represented BAT for this facility, although the differences between this and ammonia are marginal. The draft BAT conclusions document for Waste Incineration (which will update the existing sector guidance) suggests that for new plant, the BAT-AEL mg/Nm3 as a daily average for NOx should be around 50-120, and the lower end of this would only be likely to be achieved using SCR. For existing plant, which would include the proposed new EFW CHP plant, the BAT-AEL would be 50-150 mg/Nm3 but notes that the higher end of the BAT-AEL range is 180 mg/Nm3 where SCR is not applicable. The reduction to 180 mg/Nm3 is likely to be able to be met at the site by the use of additional reagent, however, if it is lower, further modification may be required. The draft document is likely to be finalised and published later in 2019. Acid Gases (SO2, HCl and HF) The BAT assessment for the Acid Gas Abatement for the proposed new plant is detailed in Appendix B1.2 of the Addendum report submitted with the application. The choice considered:

wet scrubbing;

semi-dry scrubbing;

dry scrubbing using hydrated lime; and

dry scrubbing using sodium bicarbonate. The Assessment considered air quality; photo-chemical ozone creation potential (POCP); raw materials; global warming potential (GWP), and the wastes arising from each process. Wet scrubbing was rejected early due to the generation of dense plumes, and also high volumes of effluent all requiring further treatment. There is no room for such additional on-site treatment. Options were then ranked and although all abatement option would enable the new plant to meet the mandatory ELVs, and not have an impact on air quality, the environmental performance and costs varied. Dry scrubbing using calcium hydroxide was selected as it represented BAT and the residues could be disposed of within Scotland.

The draft BAT conclusions document for Waste Incineration (which will update the existing sector guidance) suggests that for new plant, the BAT-AEL mg/Nm3 as a daily average for emissions of HCl, HF and SO2 should reduce to 2-6 mg/Nm3, <1 and 10-30 respectively, and for existing plant, 2-8 mg/Nm3, <1 and 10-40. This should be met at the higher end with the dry sorbent technique selected, although it may require additional reagent. In addition, low sulphur support fuels will be used which reduces acid gas formation. Dioxins and furans and heavy metals Dioxins and furans are discussed in sections 2.6.1 and 3.1.10 of the SRT submitted with the application. Primary measures for controlling emissions of these pollutants are generally through incinerator design in ensuring good combustion takes place and that the temperature in the combustion chamber reaches 850°C for a minimum of two seconds. In order to minimise dioxins, and prevent de-novo synthesis (a reformation of the pollutants at temperatures between 450 and 200oC) the gases are cooled quickly in the economiser, and following passage out of the economiser, are abated by injecting powdered activated carbon (PAC) into the flow. PAC is an adsorbent that attaches to volatile metals and organic micro-pollutants, in particular dioxins and furans. Measures will be employed to ensure that PAC dosing is effectively controlled. A bag filter is subsequently used to capture the bound particulate matter which contains the dioxins/furans and metals.

This is a standard technique used in waste incinerators for achieving IED Annex VI ELVs in and is therefore considered to be BAT for the proposed facility. The draft BAT conclusions document for Waste Incineration suggests that for new plant, the BAT-AEL ng/Nm3 as a daily average for new plant will reduce to <0.01-0.04 ng/Nm3 whilst existing plant must meet <0.01-0.06 ng/Nm3 from the current 0.1 ng/Nm3. In order to achieve this, optimisation of the process, good control of waste feed, on-line and off-line boiler cleaning along with dry sorbent injection including activated carbon and catalytic bag filters. The plant should reach these new limits without any significant changes, as current proposals included this. There will also be regular soot blowing of the boilers for cleaning on at least a daily basis.

Particulate Matter Abatement The treatment of acid gases, dioxins and metals, introduces additional reagents to the flue gas stream in addition to the already present ash. In order to remove these compounds, the particulates require to be captured. The multi-compartment bag filters remove particulate matter from the treated gas stream, including light dust fractions (ash) from the combustion process, unreacted calcium hydroxide and PAC, and compounds resulting from the reactions of calcium hydroxide with the acid gases and bound particulate matter. The products of reaction and fly ash collect onto the bag surfaces, forming a filter cake, and a significant amount of the reaction between the acid gases and the reagent occurs on or in this filter cake. When this cake becomes thicker, and the pressure drops, it will be

removed through compressed air pulses. Individual compartments can be isolated for maintenance without reducing the treatment and capture of particulates. Continuous emission monitoring will include particulates and will identify where emission limits may be exceeded. Periodic check monitoring of the gases will be undertaken to ensure that capture rates remain high. Wet methods were not considered as the Operator wanted to minimise water use. Ceramic filters tend to be used for high temperature incineration, and this plant does not incinerate at the high temperatures associated with eg hazardous waste. SEPA guidance recognises bag (fabric) filters as proven and reliable abatement of particulate matter to below 5mg/Nm3 and often well below this, and accept that this is BAT for the proposed EFW CHP. The draft BAT conclusions document for Waste Incineration (which will update the existing sector guidance) suggests that for new plant, the BAT-AEL mg/Nm3 as a daily average for dust will be 2-5mg/Nm3, which is achievable with good maintenance of the system selected, and this will also enable the dioxins and furans and heavy metals BAT AELs to be met.

5.21.3 Compliance with IED Requirements

Pre-acceptance of waste and raw materials are described in Section 2.1.1 of the STR. The waste types are generally MSW or similar, and can contain a wide variety of components. In general, wastes that are capable of recycling are sorted beforehand, and do not enter the incineration process.

Section 2.2 of the STR confirms that the design of the incineration plant will meet IED Article 50(4) requirements for incineration of non-hazardous waste in a combustion zone where the waste will be subject to a minimum temperature of 850oC for a minimum of 2 seconds, even under the most unfavourable operating conditions (eg minimum or maximum throughput, and low or high NCV etc). If this is not achieved, Section 2.2 of the STR confirms that the required interlocks to prevent waste feed will be operated at the facility. Section 2.3 of the STR confirms that two auxiliary burners, fired on low sulphur, light fuel oil will be fitted into into the combustion chamber to maintain the temperature if it falls, or during start up until the minimum temperature is achieved prior to waste loading as per IED Article 50(3). Once temperature is achieved, the auxiliary burners will shut down.

A Computational Fluid Dynamics (CFD) study has been submitted to demonstrate that this will be met for the design to be utilised at the proposed Dundee replacement EFW, and a commissioning plan was submitted discussing how the temperature and residence time will be verified. (Section 2.3.5 of the STR refers and a copy of the CFD was provided).

Article 50(4) of the IED requires an automatic system (ie interlocks) to be put in place to prevent waste feed if emission limit values are exceeded due to malfunction or failure of the flue gas treatment system. Section 2.2 of the STR confirms that the required interlocks will be operated at the facility

Standard permit condition 5.3.2 requires that the interlocks discussed above are present and tested.

Standard permit conditions 5.1.1(c) and (d) require that as a minimum the gases in the combustion chamber must reach a temperature of at least 850oC for a residence time of two seconds and that

should these conditions not be met that waste cannot be fed to the incinerator under Condition 5.1.1(f).

No dump stacks or bypass systems are proposed so all emissions from the incinerator will pass through flue gas treatment systems and be discharged via the 90m stack, and will be subject to continuous monitoring. Residence time on the grate is around 45-60 minutes. After waste fee stops, abatement will continue until burnout is complete.

Ash Composition Article 50 (1) of the IED .requires that bottom ashes must meet less than 3% total organic carbon or 5% loss on ignition. Sampling of the ashes will be carried out to confirm its composition meets this minimum requirements. Full characterisation of all of the ashes produced will be required during commissioning and also at regular periods once fully operational.

Permit condition 5.1.1(a) include the above controls for IBA residues, and the frequency of sampling and the parameters to be sampled for all residues are given in table 8.1 . Abnormal Emissions IED Article 46(6) sets a limit on the time of 4 hours, where incinerators may be allowed to operate when an ELV is exceeded due to eg breakdown, for specific parameters that demonstrate good combustion is still being achieved, namely PM, CO and VOCs. Standard permit condition 5.4.2 covers this requirement with a cumulative annual total of 60 hours. The 4, and 60, hours limits apply to any incineration plant with a common abatement plant. The specific ELVs for abnormal operation are contained in Condition 5.4.6. SEPA is satisfied that the standard controls contained within the draft permit will ensure that BAT and the requirements of the IED will be met for the proposed new plant. Monitoring The IED (Article 48) requires the automatic monitoring of emissions, to relevant standards as set out in Part 6 of Annex VI. Standard conditions requires this, and that the relevant monitoring standards will be met. Copies of the results must be supplied quarterly under another standard condition. This is met as discussed above in the section on Monitoring. The Operator has also confirmed that the results will be made publically available via their website, and this is already occurring for the Plymouth site operated by another member of the MVV group. SEPA is satisfied that this will meet BAT for the installation.

6 OTHER LEGISLATION CONSIDERED

Nature Conservation (Scotland) Act 2004 & Conservation (Natural Habitats &c.) Regulations 1994

Is there any possibility that the proposal will have any impact on site designated under the above legislation? Yes

Screening distance(s) used – 15km

Are there any SSSIs within the area screened? Yes – 4 sites: the Firth of Tay and Eden Estuary

SAC/SPA, the River Tay SAC, Barry Links SAC and Tentsmuir NNR. Has SNH been consulted under section 15(5) of the 2004 Act? Yes – by letter on 14 May 2018 See section 5.2 above on impact of air emissions, and below: SEPA Ecology reviewed the habitat assessment, and confirmed that an investigation of the Critical Levels across each of the designated sites identified above indicated that the background levels for both NOx and SO2 were well below the CLevel for each site and associated habitats.

Modelling results show that the process contribution for atmospheric concentrations of both NOx and SO2 were below the 1% PC. The exception was annual mean NH3 when compared to the standard for lichens and bryophytes. This was higher due to background concentrations already being greater than the EAL. However, the maximum 24hr mean concentration was predicted to decrease with EfW CHP facility operation compared with the existing EFW facility operation.

Where the process contribution (PC) > 1% and the predicted environmental concentration (PEC) > 100% of the relevant long-term benchmark (e.g. critical load) then a conclusion of likely significant effect is reached.

While a Process Contribution (PC) of <1% of the Critical Load is assumed to be a non-significant effect, exceedance of the 1% figure does not necessarily imply a significant impact, rather a value above which it is appropriate to undertake a more detailed assessment of effects. The significance of the exceedance depends on factors such as the duration of the impact, the proportional increase over current levels and the sensitivity of the habitats affected.

It is SEPA’s view that the proposal will not have a likely significant effect on the designated sites within the screening distance (listed above). No further assessment is required.

Other legislation?

None

7 ENVIRONMENTAL IMPACT ASSESSMENT AND COMAH

How has any relevant information obtained or conclusion arrived at pursuant to Articles 5, 6 and 7 of Council Directive 85/337/EEC on the assessment of the effects certain public and private projects on the environment been taken into account? An EIA was completed as a part of the planning process and the required mitigation effects have been included in the planning conditions.

How has any information contained within a safety report within the meaning of Regulation 7 (safety report) of the Control of Major Accident Hazards Regulations 1999 been taken into account? N/A

The site does not hold chemicals and substances in quantities that would be above the threshold for COMAH regulation.

8 DETAILS OF PERMIT

Do you propose placing any non standard conditions in the Permit? Yes

Condition number: 2.8.1 By 31 May 2019, the Operator shall provide SEPA with a detailed plan of the implementation programme from construction through to Commissioning (“the Construction and Commissioning Plan”) for the Moving Grate EFW CHP Plant. Said Plan should include the best estimates of the start date for each major stage of construction and Commissioning, and for the planned commencement of burning on oil and on waste.

Justification: This has been introduced to qualify the timescales in other Prior Operating conditions, and tie them into the hot commissioning phase at the Moving Grate EFW CHP Plant only. Wording is similar to that used in PPC/A/1157446

Condition number: 2.8.2 An update of progress against the Construction and Commissioning Plan programme required by 2.8.1 shall be provided to SEPA quarterly, within 10 days of the last day of March, June, September and December, each year, until the Report required by Condition 2.9.7 is submitted.

Justification: This has been introduced to keep a track on the commissioning phase and the likely key phases such as the start of burning of oil and of waste at the Moving Grate EFW CHP Plant only. Wording is similar to that used in PPC/A/1157446.

Condition number: 2.8.6 (Prior Commissioning & Prior Operating) No later than 9 months prior to the planned burning of any fuel or waste as part of Commissioning of the Moving Grate EFW CHP Plant, indicated in the Construction and Commissioning Plan required by Condition 2.8.1, the Operator shall submit to SEPA the Soil and Groundwater Monitoring Plan required by Condition 7.3.7, for agreement. Said Plan shall include locations, a construction timetable, and details of the design(s) for the groundwater monitoring boreholes, for the collection of groundwater samples across the whole Permitted Installation Justification: This has been pulled from the requirement in Standard condition 7.3.7 to ensure submission of the plan in advance of commissioning, as it is important that we agree the locations in advance in order to also meet the requirements of 2.8.7 and 2.8.9. It would have been beneficial to sort this out prior to the commencement of construction of the new EFW CHP plant, however, that has already started, so it is now important to get the locations agreed and construct the boreholes and undertake the baseline sampling before the abatement chemicals and fuels are brought onto the area for the new plant. Added the words ‘…across the whole Permitted Installation’ to the end of the condition as the monitoring applies across the whole site, not just around the new plant, whilst most of the prior operating and prior commissioning one apply only to the new EFW CHP plant. Details of the borehole design are also required to ensure they are suitable for the ground conditions into which they will be placed.

Condition number: 2.8.7 (Prior Commissioning & Prior Operating) No later than 6 months prior to the planned burning of any fuel or waste as part of Commissioning of the Moving Grate EFW CHP Plant, indicated in the Construction and Commissioning Plan required by Condition 2.8.1, and following SEPA’s written agreement to the Groundwater Monitoring Plan locations, required by Condition 2.8.6, the groundwater monitoring boreholes, referred to in Condition 2.8.6 shall be constructed as agreed. Additionally, soil samples shall be collected from all of the said boreholes during their construction, for subsequent analysis, as required by Condition 7.3.6.

Justification: This rewords template Conditions 2.8.5 and 2.8.6 which were based on conditions used in PPC/A/1150156, and tightens up on the design, ensures construction takes place prior to fuel or abatement chemicals or waste coming onto the area of the new EFW CHP plant and ensures that the soil samples, which can only be taken during the borehole construction, are taken.

Condition number: Condition 2.8.8 (Prior Commissioning & Prior Operating) A borehole construction report shall be submitted to SEPA within 1 month of completion of the boreholes required by Conditions 2.8.6 and 2.8.7. Said report shall include all borehole construction logs, as well as the depth of all groundwaters encountered, and details of the soil sampling depths during installation. All depths to be recorded in metres Above Ordnance Datum (mAOD). Justification: This is added because it is important, (including for future surrender of the permit) to have details of the boreholes, and layers of strata they go through and to understand where the groundwater sampling relates to and how any plumes on potential contamination could spread. Also it will give context to the samples of groundwater and of the soils that also must be sampled at the point of construction.

Condition number: Condition 2.8.9 (Prior Commissioning & Prior Operating) No later than 3 months prior to the planned burning of any fuel or waste as part of Commissioning of the Moving Grate EFW CHP Plant, indicated in the Construction and Commissioning Plan required by Condition 2.8.1, the first assessment from the monitoring of Relevant Hazardous Substances (RHS) in the groundwater, as required by Condition 7.3.5, and the soils, as required by condition 7.3.6, shall be submitted to SEPA Justification: The requirement for the groundwater and soils assessment is pulled out of the Standard Conditions 7.3.5 and 7.3.6 and this is actually required prior to burning of any waste as part of commissioning. The reason for this is that additional chemicals will be in use once ‘hot’ commissioning starts, so this will ensure that the sampling is representative of the ground prior to the additional activity at the new Moving Grate plant.

Condition number: Condition 2.8.10 (Prior Commissioning & Prior Operating) At least two months prior to the acceptance of any waste into the Moving Grate EFW CHP Plant, indicated in the Construction and Commissioning Plan required by Condition 2.8.1, the building integrity and the effectiveness of the air extraction system in minimising fugitive odour shall be assessed by smoke testing and a report submitted to SEPA within one month of the test. Justification: Due to the odorous nature of the waste, it is important to establish that the escape of odour air is unlikely before any waste is brought onto the site. This is adapted from Permits PPC/A/1110002 & PPC/A/1136072.

Condition number: Condition 2.8.11 (Prior Commissioning & Prior Operating)

At least one month prior to carrying out the first smoke test, required by Condition 2.8.8 the methodology for the smoke testing shall be submitted to SEPA for agreement. Justification: This is required to ensure that Condition 2.8.8 is done in such a way that it is demonstrated to SEPA that the air removal will be sufficient to the treatment system to prevent escape.

Condition number: Condition 2.8.12 (Prior Commissioning & Prior Operating) No later than 9 months prior to the planned burning of any fuel or waste as part of Commissioning of the Moving Grate EFW CHP Plant, indicated in the Construction and Commissioning Plan required by Condition 2.8.1, the Operator shall provide SEPA with a report detailing how BAT has been applied to prevent or reduce noise from individual noise sources identified in report Number M139854 by Muller-BBM, dated 29 August 2018. As a minimum the said report shall include the following:

a) an assessment of different options to determine which techniques and/or equipment achieve the lowest combined noise levels during normal operations;

b) an assessment of the potential differences in noise levels during abnormal, start-up, shut-down, and emergency operational conditions, and indicate additional measures to be utilised during each of these operational conditions;

c) a sensitivity analysis of any potential impact on noise receptors, particularly those identified at locations F&G, (Muller-BBM report M139854).

d) a sensitivity analysis of any impact on all noise receptors due to any planned removal of the Fluidised Bed Plant and any associated infrastructure or part thereof;

e) the assessments and analysis shall take into account the predicted 4m bedroom height level for night time modelling analysis, in addition to the 1.5m level used for daytime surveys indicated in the Muller-BBM report M139854 model.

Justification: A report based on only normal operations was submitted, which indicates that minimum criteria would be met for noise emissions, but does not demonstrate emissions during abnormal or other operational modes, and also does not account for the removal of the old plant, or night time noise levels at bedroom height, or consider different options for individual noise source containment. This Condition was peer reviewed by SEPA noise specialist.

Condition number: Condition 2.8.13 (Prior Commissioning & Prior Operating) At least 2 months, prior to the planned burning of any fuel or waste as part of Commissioning of the Moving Grate EFW CHP Plant, indicated in the Construction and Commissioning Plan, the Operator shall submit to SEPA a Plan to demonstrate how Condition 2.9.8 will be met

Justification: Condition 2.9.8 requires that there will be no burning of waste in both the existing and the new plant at the same time, even during Commissioning. This was part of a Planning Condition also. In order to ensure that this will be undertaken in a satisfactory manner, the Operator will need to explain their intentions, and how they will operate the supply of waste into each plant to ensure that the incineration plant is adequately fed to prevent issues with incomplete combustion.

Condition number: Condition 2.9.8 (Commissioning)

During Commissioning of the Moving Grate EFW CHP Plant, no waste shall be simultaneously incinerated in the Fluidized Bed Plant and the Moving Grate EFW CHP Plant. Justification: This was agreed at the pre-application and Planning stages with the Operator following submission of the Air Quality modelling and consideration of the location of the plant. The Condition has been peer reviewed.

Condition number: Condition 2.9.9 (Commissioning) Following First Operation of the Moving Grate EFW CHP Plant, waste shall cease to be incinerated in the Fluidized Bed Plant. Justification: This was agreed at the pre-application and Planning stages with the Operator following submission of the Air Quality modelling and consideration of the location of the plant. The old plant will not continue to operate, and will be decommissioned. The Condition has been peer reviewed.

Condition number: 3.1.4 (Noise & vibration) Noise emissions associated with the Permitted Activities shall not contain any Audible Tonal Noise (as defined in BS4142:2014 and assessed using narrow band analysis defined in Annex D of BS4142:2014) at night time (23:00 hrs to 07:00hrs) at any residential noise sensitive receptor. Justification: As the noise modelling has not considered the tonal noise under different conditions, this condition, based on and similar to one used in PPC/A/1157446, is appropriate to ensure we have a condition that is appropriate should tonal noise occur. Residential locations to the south of the site, will have a new operating plant situated slightly nearer than the existing one, and with different potential noise sources. The inclusion of this condition will limit the night-time tonal noise to these nearby sensitive receptors. In the event that complaints are received, this specifies what method of assessment would be expected, but without trying to define every potential individual receptors or limit it by basing it on only the 7 receptor locations used on the model. The standard conditions 3.1.1 and 3.1.2 requiring a systematic assessment and the submission of a noise and vibration management plan, should take the requirements of this condition into consideration.

Condition number: 3.1.5 (Noise & vibration) In order to validate the noise modelling provided in the Mueller-BBM Report M139854/01, and the report required by Condition 2.8.10, within three months of First Operation of the Moving Grate EFW CHP Plant, the operator shall carry out noise monitoring at the Site Boundary and receptors to determine the specific noise level for day-time and night-time) of the Permitted Installation. The monitoring shall be carried out during normal incineration operations in accordance with British Standard 4142:2014. The specific noise levels for day-time and night-time shall be used to validate the predicted operational noise levels. The results of the monitoring shall be recorded and submitted to SEPA with an assessment of the results, within one month of the monitoring being conducted. Justification: As this will be a new plant, with different noise sources, some of which are mounted higher up, and/or nearer to sensitive receptors, it is important to verify the modelling, but the modelling itself requires review in the Prior Commissioning Conditions, so this also has to be captured. This Condition has been peer reviewed by a SEPA noise specialist.

Condition number: 3.2.6

All doors and openings to any area where waste is stored shall be kept closed at all times, other than to allow entry and exit of vehicles and personnel.

Justification: This is a new Condition, based on PPC/A/1110002 and also used at PPC/A/1136072. The Operator opted for a single large door, and in order to ensure that the odorous air within the tipping hall is contained, the door should be closed when there is no access requirement. The use of air in the incineration process is designed to ensure a negative air flow (ie into the building), however, this site has close proximity to receptors, and it is felt that this would enable SEPA to regulate against a condition if odour is not adequately contained.

Condition number: 3.2.7 The integrity of the infrastructure, and the effectiveness of the air extraction system in minimising fugitive odours shall be assessed annually by smoke testing, of each area where waste is stored, by a methodology agreed by SEPA under Condition 2.8.11 and the outcomes from each assessment recorded and reported to SEPA within one month of the test.

Justification: This is a new Condition, to ensure regular assessment of the integrity of the infrastructure. The moist acidic conditions within such process buildings can lead to corrosion and this can lead to odour escape. Smoke testing should highlight if this is occurring, and will also enable SEPA to confirm that there is adequate draw. Demonstrating the draw could potentially be undertaken in advance of installing the carbon

Condition number: 3.2.8 During any period of planned or unplanned shutdown of the incineration line(s), whenever waste is present in the tipping hall, the odorous air shall be collected and treated in the associated Odour Abatement unit. A record of each occasion when the Odour Abatement System is required to be used shall be maintained. Justification: This is required as when the incineration is off-line, there would be no negative air-flow to retain the odorous air whenever the door is open. By requiring this, the Operator will be obligated to use the system that ensure the air is captured and treated.

Condition number: 3.2.9 Within 1 month of First Operation of the Moving Grate EFW CHP Plant, the Operator shall provide a written report to SEPA on the methodology to be used for monitoring of odour at emission point A5 when the incineration line is shut down. Said report shall include the frequency at which monitors should be carried out. Justification: to allow the Operator to determine the most suitable proposal for this monitoring, which should include consideration of the minimum duration of a shut down before monitoring will be undertaken. Monitoring is likely to require an assessment of the sample by an odour panel within a 24 hour period.

Condition number: 4.4.1 Subject to Condition 2.9.9, the unloading and sorting of bulky municipal solid waste, as pre-treatment of waste for incineration, may commence and shall take place only within the tipping hall of the Fluidised Bed Plant.

Justification: Once the existing plant closes, the tipping hall itself will be retained, and utilised for bulky waste sorting, which currently takes place at the adjacent Waste Transfer Station.

Do you propose making changes to existing or template text, tables or diagrams within the permit?

Yes – all existing conditions being replaced with current template version, subject to changes to those standard conditions as indicated below.

Outline of change: Interpretation of terms : First operation

Details including justification: In the current template, Interpretation of terms, “First Operation” means the first receipt of waste for incineration, after the Cessation of the Commissioning activities; This is amended to read ‘…the first burning of waste for incineration, after the Cessation of the Commissioning activities’. This is because first receipt of waste has already taken place at this installation, and will have taken place in the new EFW CHP Moving Grate plant because waste will be required to be used for the actual commissioning of the plant. The cessation of waste relates to the plant becoming operational, and therefore starting the activity of burning of the waste for beneficial production of heat and disposal of the waste by burning. The activity is not receiving of the waste.

Outline of change: Interpretation of terms : High Level of efficiency

Details including justification: This is amended to “High level of energy efficiency” in line with the wording in Condition 2.7.1

Outline of change: Interpretation of terms :

Details including justification: The following are removed as they are not included in the Variation wording: “AMS” “Chapter IV of IED” “Climate Change Agreement” “Co-incineration and Co-incineration Plant” “Start up Period” “Shut down Period” “Specified Waste Management Activity” “Waste Incineration Installation” “Waste Oil”

Outline of change: Condition 2.7.1 (Heat & Power)

Details including justification: added the words ‘of the Moving Grate EFW CHP Plant’ after Cessation of Commissioning, as it is only the new plant that will be required to meet the TTWG targets. The old plant, which will be decommissioned, only has to meet a ‘high level of efficiency’ until it closes

Outline of change: Condition 2.8.3 (Prior Commissioning & Prior Operating)

Details including justification: added the words ‘the planned burning of any fuel or waste as part of’ [Commissioning] …’of the moving grate EFW CHP Plant, indicated in the Construction and Commissioning Plan’ as the timeline relates only to the new Plant which is the Moving Grate EFW CHP Plant, and we do not need to know this prior to the early stages of Commissioning (ie planning and electrical connection.

Also paragraph e) has been divided so its clear that electricity will go to the National Grid, and heat will go to Michelin and/or other users. This situation will be clarified with the submission required in 2.7.1.

Outline of change: Condition 2.8.4 (Prior Commissioning & Prior Operating)

Details including justification: added the words ‘…the planned burning of any fuel or waste as part of’ [Commissioning] …’of the moving grate EFW CHP Plant, indicated in the Construction and Commissioning Plan’ and ‘…and/or another user(s)…’ This was added as we do not need to know this prior to the early stages of Commissioning (ie planning and electrical connection, and also, this clarifies that it relates only to the new Moving Grate plant. The words ‘Permitted Installation’ have also been replaced with the term ‘Moving Grate EFW CHP Plant’ as this condition only relates to the new plant.

Outline of change: Condition 2.8.5 (Prior Commissioning & Prior Operating)

Details including justification: : added the words ‘…the planned burning of any fuel or waste as part of’ [Commissioning] …’of the moving grate EFW CHP Plant, indicated in the Construction and Commissioning Plan’ This was added as we do not need to know this prior to the early stages of Commissioning (ie planning and electrical connection, and also, this clarifies that it relates only to the new Moving Grate plant.

Also added the words ‘…or other equivalent methodology or standard as agreed in writing with SEPA’ to the end as the Condition may use a German equivalent standard now which is more up to date. SEPA will determine this if suitable once the details are submitted, but this allows for the change without varying the permit again.

Outline of change: Condition 2.9.7

Details including justification: added the words ‘…of the Moving Grate EFW CHP Plant’ This was added as to clarify that it relates only to the new Moving Grate plant.

Outline of change: Condition 2.10.1 (Start up/Shut down)

Details including justification: The words ‘…burning waste as part of the…’ prior to Commissioning are added, as we do not need this information any earlier, with regard to the new plant, and it will be an amendment to the existing plan.

Outline of change: Condition 3.1.1

Details including justification: Changed the wording from every 4 years to every 2, and also ‘…whenever….’ to ‘….within one month of….’. The reason for this is to ensure that the assessments are carried out more frequently as we have seen an increase in noise complaints from similar plant, and to ensure the assessments are carried out within a short timescale. This is not apparent in the original wording.

Outline of change: Condition 3.2.3 Paragraph e)

Details including justification:

Added the word ‘identification of a material failure or reduced abatement efficiency from the Permitted Installation odour abatement systems. This has been added due to experience at other sites, and is based on wording from PPC/A/1110002.

Outline of change: Condition 4.2.2

Details including justification: This has been split to differentiate between the maximum load that can be treated in each of the two plants, as they have different design loading capacities, and also reworded to allow the flexibility of tonnage throughput, depending on the CV of the waste. The lower the CV, the more waste that can be put through the system. The 2 plants are not permitted to incinerate waste at the same time, under the requirements of Conditions 2.9.8/2.9.9.

Outline of change: Condition 4.5.3

Details including justification: Added the words ‘…of the operational incineration plant’. This is required to qualify that other unloading of vehicles for sorting purposes can take place in the plant that is not operational as an incinerator.

Outline of change: Condition 4.5.6

Details including justification: This has been amended to remove the set frequency cleaning requirement as each area has different requirements, and the bunker is not cleared out fully for normal operational purposes. The used of a planned cleaning regime in line with a Hygiene Plan is used in PPC/A/1150156 and PPC/A/1157446 and wording is similar to these.

Outline of change: Condition 5.1.1 b) was removed

Details including justification: The requirement for a minimum % oxygen concentration in the flue gases as it exits the secondary combustion zone was a requirement under the Hazardous Waste Incineration Directive which is now replaced. This is no longer a requirement in the current IED. Some operational variability is likely, and it was not in the Operators permit for the existing EFW plant. The requirement to monitor oxygen, and other relevant parameters such as waste feed etc are far more important, and 5.2.2 a) ensures that monitoring is undertaken, in line with the requirements of the IED. As a result of this, amendments to numbering were made within Conditions 2.8.5, 2.9.4b), 5.1.3, 5.2.4, 5.3.2, 5.3.2 a) and b), 5.3.3 c),

Outline of change: Condition 5.1.1 c) – this is 5.1.1.d) on template

Details including justification: After the words less than 2 seconds, added the words ‘…after the last injection of combustion air…’ which was requested by the Operator, and reflects the requirements of the IED legislation so SEPA accept this change.

Outline of change: Condition 6.3.9 g)

Details including justification: Added as it is an EC requirement for reporting periods of Abnormal Operation under IED.

Outline of change: Table 6.2

Details including justification: The reference period for periodic monitoring now refers to ‘Average value of three consecutive measurements of at least 30 minutes each’ which is in the draft BREF and is considered good practice.

Outline of change: Conditions 7.1.3 to 7.1.11 relating to ELVs, and sections 7.2, 7.3 and 7.4 of the template relating to Monitoring Standards and data handling. Table 7.2 (ELVs) and 7.3 (Two tier consents) of the template are also not required and have been left out.

Details including justification: These were removed as the process water is limited and discharges only to sewer. No limits are being set as the water should not be contaminated, but must comply with GBRs 10 and 11 for the low risk areas discharging to the water environment via the Surface Water sewer operated by Scottish Water. Table 7.1 is retained to provide details of the discharge points and the discharge source(s). Sampling of the intermittent Surface water discharges, to calculate mass concentrations, is not required. The trade effluent consent from Scottish Water sets the limits to foul sewer.

Outline of change: Condition 7.2.1

Details including justification: paragraph d wording has been amended to reflect the different containment capacities at each of the two incineration plant to capture contaminated water, as these are not constructed as a single site-wide system.

Outline of change: Conditions 7.3.5 & 7.3.6

Details including justification: Removed the words ‘The first assessment shall be completed by 9 months prior to Commencement of Commissioning of the Incineration Process. This is now required by the Prior Commissioning condition 2.8.7 (see above)

Outline of change: Table 8.1

Details including justification: Have added a column on Reporting requirements, to clarify the frequencies of reporting to SEPA. This will allow SEPA to confirm the status of the waste residues as hazardous or non-hazardous.

Outline of change: Schedule 9 removed

Details including justification: Schedule 9 requires Environmental monitoring beyond the site boundary – to determine baseline concentration is soil and vegetation. The Installation is within an industrial zone, and has had a previous incineration plant situated here, in addition to the current existing fluidized bed. The requirement for monitoring beyond the boundary relies on third party agreement, which cannot be guaranteed in future. This was considered to be excessive for a replacement installation, and all Schedule 9 Conditions have been removed.

9 EMISSION LIMIT VALUES OR EQUIVALENT TECHNICAL PARAMETERS/ MEASURES

Are you are dealing with either a permit application, or a permit variation which would involve a review of existing ELVs or equivalent technical parameters? Yes

Emission limit values: Air

Substance: Odour Relevant emission benchmarks: 1.0 OUE/m3 at the receptor ELV: as set out in permit Table 6.2 (6,0001.0 OUE/m3 at A4 and 3,0001.0 OUE/m3 at A5) Emission point: emission point A4 existing plant) and A5 New EFW CHP Plant) Rationale: To ensure that odour emissions from the Waste Reception Area are sufficiently controlled so that there is no emission of odour above the threshold of 1 OUE/m3 at nearby sensitive receptors as a 98th percentile of hourly averages. See Section 5.7 for further information.

Details of any equivalent technical parameters adopted to supplement or replace ELVs: ELVs are set to meet recommended maximum concentrations at the receptor as per modelling submitted during application process.

Details of any derogations from the ELVs set out in the BAT conclusions; None

Has an Annex been inserted to the permit containing reasons, assessment and justifications for setting the value: Not applicable

Details of any temporary derogation for the use of emerging techniques. NB Such temporary derogations do not require PPD consultation or the insertion of reasons etc. into the permit None applied

Substance: For continuously measured parameters monitored by the Continuous Emission Monitoring Systems (CEMS) and parameters which are monitored through periodic measurement such as dioxins and furans and hydrogen fluoride, the limits are taken directly from Annex VI of the IED and are mandatory and standard for waste incinerators. An additional ELV has been set for ammonia and itrous oxide for both continuous and periodic monitoring. Whilst none is specified in Annex VI of IED, this is considered necessary to control ammonia slip associated with the SNCR NOx abatement system. See Section 5.2.1 for further discussion. In the case of periodic measurements for parameters, emission limits have been set based on the the IED limits. Where additional confirmatory periodic monitoring of parameters measured continuously such as oxides of nitrogen has been required then limits are set based on the half hourly 100th percentile limit as this most closely approximates the conditions under periodic measurement where the sample times are around 30 minutes. Emissions of smoke are not anticipated from the technology and abatement selected but as a precaution a limit based on the Ringelmann scale has been incorporated into Table 6.2. Ringelmann shade 1 is the lightest shade limit in the scale (zero being no visible smoke impact) and is applied during start-up when smoke emission is most likely. Visible plume is anticipated from the facility incinerator discharges and limits have been incorporated to require that no persistent mist or fume be discharged. NB it is understood that under certain weather conditions there will be a continuously present but short condensation plume from the incinerator. This is inevitable for all combustion emissions. Relevant emission benchmarks: For incineration emissions - IED Annex VI, Part 3

ELV: : as set out in permit Table 6.2 Emission point: A1 Rationale: As above.

Details of any temporary derogation for the use of emerging techniques. NB Such temporary derogations do not require PPD consultation or the insertion of reasons etc. into the permit None.

Details of any derogations from the ELVs set out in the BAT conclusions; None

Has an Annex been inserted to the permit containing reasons, assessment and justifications for setting the value None - not applicable

Details of any temporary derogation for the use of emerging techniques. NB Such temporary derogations do not require PPD consultation or the insertion of reasons etc. into the permit None

Emission limit values Land NONE

Substance: N/A ELV: N/A Emission point: N/A Rationale: N/A

Details of any equivalent technical parameters adopted to supplement or replace ELVs: None

Details of any derogations from the ELVs set out in the BAT conclusions; None

Has an Annex been inserted to the permit containing reasons, assessment and justifications for setting the value None - not applicable

Details of any temporary derogation for the use of emerging techniques. NB Such temporary derogations do not require PPD consultation or the insertion of reasons etc. into the permit None - not applicable

Emission limit values Noise and Vibration

Substance: Noise ELV: None specified, but tonal noise not permitted. Emission point: beyond site installation boundary/at nearest sensitive receptors Rationale: See discussion in Section 5.17 and time limited waste deliveries 0700-2000hrs Systematic assessment required following a change – so once commissioned, a new assessment must be undertaken.

Details of any equivalent technical parameters adopted to supplement or replace ELVs: n/a

Details of any derogations from the ELVs set out in the BAT conclusions; n/a

Has an Annex been inserted to the permit containing reasons, assessment and justifications for setting the value No

Details of any temporary derogation for the use of emerging techniques. NB Such temporary derogations do not require PPD consultation or the insertion of reasons etc. into the permit None

10 PEER REVIEW

Has the determination and draft permit been Peer Reviewed? Yes

11 FINAL DETERMINATION

Issue a Permit Variation– Based on the information available at the time of the determination SEPA is satisfied that

The applicant will be the person who will have control over the operation of the installation/mobile plant,

The applicant will ensure that the installation/mobile plant is operated so as to comply with the conditions of the Permit,

The applicant is a fit and proper person (specified waste management activities only),

Planning permission for the activity is in force (specified waste management activities only),

That the operator is in a position to use all appropriate preventative measures against pollution, in particular through the application of best available techniques.

That no significant pollution should be caused.

12 REFERENCES AND GUIDANCE

The Pollution Prevention and Control (Scotland) Regulations 2012, known as ‘PPC2012’. SEPA’s Thermal Treatment of Waste Guidelines 2009 and 2014. SEPA Odour Guidance, Version 1, January 2010. UK technical Guidance note s5.01, Guidance for the incineration of Waste and Fuel Manufactured from or Including Waste, known as ‘UK Technical Incineration Guidance’. UK Technical horizontal guidance note H1 Environmental Assessment and Appraisal of BAT, known as ‘UK guidance note H1’ IPPC BAT reference document (BREF) on Best Available Techniques for Waste Incineration, known as ‘The Waste Incineration BREF’ Best Available Techniques (BAT) Reference document on Waste Incineration (Draft 1 – May 2017) JRC Science for policy report

Technical Guidance Note (TGN) M1 Sampling requirements for stack emission monitoring. Environment Agency, Aug 2017 v8. Technical Guidance Note (TGN) M2 Monitoring of stack emissions to Air. Environment Agency, Aug 2017 v12. ‘Releases from municipal waste incinerators - Guidance to applicants on impact assessment for group 3 metals’ – Environment Agency (version 4). CERC ‘ADMS User Group Meeting’ presentation – 2012 Permit documents Original permit from 24/11/2005 and subsequent variations and consolidations; Responses to Schedule 7 Further Information Notice issued 26 June 2018 - received in July and August 2018 Response to clarification request received 04 December 2018