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HomeMy WebLinkAbout2560416 - F.I. Received Doc. - Ordour Impact Assessment ODOUR IMPACT ASSESSMENT & AIR DISPERSION MODELLING REPORT FOR MULLANARRY ENVIRONMENTAL T/A JC ENVIRONMENTAL AT MULLANARRY CARRICKMACROSS CO. MONAGHAN Prepared for Mullanarry Environmental T/A JC Environmental Prepared by Traynor Environmental Ltd Reference Number 25.574 TE Date of Issue 16th September 2026 Belturbet Business Park, Creeny, Belturbet, Co Cavan T: + 353 49 9522236 E: nevin@traynorenv.com www.traynorenvironmental.ie REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 2 This document is an Odour Impact Assessment and Air Dispersion Modelling Report for the construction of a proposed development for Mullanarry Environmental trading as JC Environmental Issue Date Details Prepared by Checked/Approved by 1 16th September 2026 Final Angela Kelly Environmental Consultant Nevin Traynor Environmental Scientist Project Title: Odour Impact Assessment and Air Dispersion Modelling Rpeort Client: Mullanarry Environmental trading as JC Environmental Office Reference: 25.574 TE Status: Final Date: 16th September 2026 Technical Reviewer Signature Nevin Traynor BSc Environmental Scientist Date: 16th September 2026 Traynor Environmental Belturbet Business Park Creeny Belturbet Co. Cavan H14AY94 Tel: 049 9522236 Email: nevin@traynorenv.ie © This Report is the copyright of Traynor Environmental Ltd. Any unauthorised reproduction or usage by any person other than the addressee is strictly prohibited. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 3 1.0 INTRODUCTION 4 1.1 Commission and Purpose 4 1.2 Planning Further Information 4 1.3 Scope and Status of Assessment 4 2.0 SITE AND PROPOSED OPERATIONS 6 2.1 Site Location 6 2.2 Receiving Environment 7 2.3 Proposed Waste-Processing Activity 7 3.0 ODOUR CONTROL SYSTEM 10 3.1 Proposed Abatement Arrangement 10 3.2 Monashell Technology 10 3.3 OCU Design and Emission Parameters 10 3.4 Ventilation Design Basis 11 3.5 OCU Performance and Air Dispersion Assessment Basis 12 4.0 ASSESSMENT CRITERIA 13 4.1 Odour Criterion 13 4.2 Background and Cumulative Odour 13 5.0 SENSITIVE RECEPTORS 15 5.1 Receptor Context 15 5.2 Receptor Distance Assessment 15 6.0 Dispersion Modelling Methodology 17 6.1 EPA AG4 Assessment Framework 17 6.2 Meteorological Dataset Review 17 6.3 Gaussian Dispersion Screening Model 18 6.4 Source Term 19 6.5 Model Scenarios 20 6.6 Building Effects and Stack Height 21 7.0 SCREENING RESULTS 21 7.1 Concentration with Distance 22 7.2 Residential Receptor Results 23 7.3 Design-Target Screening Envelope 23 7.4 Reduced-Performance Sensitivity Envelope 8.0 MITIGATION AND OPERATIONAL CONTROLS 24 9.0 CONCLUSIONS 26 Appendix A OCU process schematic 29 B Met Éireann Ballyhaise station 31 C Odour Sensitive receptors and site boundary monitoring locations 33 REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 4 1.0 INTRODUCTION 1.1 Commission and Purpose Traynor Environmental Ltd. was commissioned to undertake an Odour Impact Assessment and Air Dispersion Assessment in respect of the proposed waste-processing development at Mullanarry, Carrickmacross, Co. Monaghan. The purpose of this assessment is to evaluate the potential for odour emissions associated with the proposed development, characterise the proposed odour-control system and controlled atmospheric emission source, assess potential impacts at nearby sensitive receptors and demonstrate the effectiveness of the proposed odour-abatement measures. The assessment considers the proposed operational activities, enclosure and extraction arrangements, proposed odour-control unit, treated odour emission characteristics, local meteorological conditions, nearby residential receptors and existing background odour sources within the surrounding environment. The air dispersion assessment has been undertaken using a conservative Gaussian dispersion screening methodology, taking account of the relevant principles and assessment requirements of EPA Guidance Note AG4. Sensitivity testing has also been undertaken across a range of odour-control-unit outlet concentrations in order to assess the consequences of reduced treatment performance. 1.2 Planning Further Information Monaghan County Council, under Planning Reference 25/60416, requested Further Information in relation to potential noise, odour and air-quality impacts associated with the proposed development. In particular, Item 1 requested:  an odour assessment taking account of EPA Air Guidance Note AG5;  an air dispersion model taking account of EPA Guidance Note AG4; and  consideration of background odour conditions and nearby sensitive receptors. The Planning Authority also noted that the previously submitted Odour Management Plan described the surrounding environment as predominantly agricultural and that the referenced boundary odour-monitoring locations had not been included. This assessment has therefore been prepared to address the odour and air-dispersion elements of Item 1. The receiving environment has been reassessed having regard to the presence of nearby residential development, commercial uses, agricultural lands and existing livestock-related odour sources. The assessment also considers the location and sensitivity of nearby residential receptors and the presence of three operational piggeries in the surrounding area, which represent identifiable pre-existing potential sources of livestock/manure odour. 1.3 Scope and Status of Assessment This report provides an assessment of the potential odour impacts associated with the proposed development and includes:  a description of the proposed waste-processing activities;  identification of potential odour-generating activities;  details of the proposed enclosure, extraction and odour-abatement system;  characterisation of the proposed controlled atmospheric emission source;  identification of an appropriate odour assessment criterion; REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 5  consideration of the surrounding receiving environment and existing background odour sources;  identification and assessment of nearby sensitive residential receptors;  review of representative meteorological conditions;  air dispersion assessment of the proposed controlled OCU discharge;  sensitivity testing across a range of treated odour concentrations;  consideration of reduced OCU performance and abnormal operating conditions; and  identification of operational and mitigation measures required to minimise the potential for off-site odour impacts. The assessment has been prepared having regard to the supplied planning documentation, EPA Guidance Notes AG4 and AG5, the proposed Anua odour-control-unit information and available supplier performance data. The dispersion assessment is based on the proposed controlled discharge from the odour-control system and adopts conservative assumptions in assessing potential ground-level odour concentrations at surrounding sensitive receptors. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 6 2.0 SITE AND PROPOSED OPERATIONS 2.1 Site Location The application site is located at Mullanarry, Carrickmacross, Co. Monaghan, on the outskirts of the Carrickmacross urban area. The submitted site-location drawing identifies an application area of approximately 0.581 ha. The approximate centre of the application site is located at ITM E 683900, N 803370, corresponding approximately to 53.9728° N, 6.7211° W. The site comprises an established commercial/industrial premises containing existing buildings, hardstanding, access arrangements and associated infrastructure. The proposed development relates principally to the use of part of the existing premises for waste-processing activities together with the provision of associated odour-control infrastructure. The specifically identified controlled atmospheric discharge associated with the proposed odour-control unit is designated A1 and is located at ITM E 683929, N 803346. Figure 1.0 - Site location plan submitted with the planning application REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 7 2.2 Receiving Environment The receiving environment surrounding the application site is of a mixed character. Agricultural lands occur principally to the west and south-west of the site; however, established residential properties and residential estates are also present within the surrounding area, together with commercial premises and the urban edge of Carrickmacross. Accordingly, the surrounding environment is not characterised as predominantly agricultural for the purposes of this assessment. Particular regard has been given to the presence of nearby residential properties, which are treated as high-sensitivity receptors in the assessment of potential odour impacts. Three operational piggeries have also been identified within the surrounding area, with approximate pig populations of 1,500, 250 and 250 animals respectively, representing an approximate combined population of 2,000 pigs. These facilities constitute separate and established potential sources of livestock- and manure-related odour within the existing receiving environment. The presence of these existing odour sources is relevant to the assessment of background odour conditions and to the interpretation of any odour observations or complaints within the wider area. Potential odour associated with the proposed development must therefore be considered in the context of the existing mixed receiving environment and the presence of other identifiable odour sources. 2.3 Proposed Waste-Processing Activity The proposed development provides for the receipt and processing of waste associated principally with drainage and wastewater-related services. The waste streams identified within the planning documentation include:  19 08 01 – screenings;  20 03 03 – street-cleaning residues; and  20 03 06 – waste from sewage cleaning. Waste received at the site will be inspected and accepted in accordance with the applicable waste acceptance procedures prior to unloading or decanting within the designated processing area. Material will then be screened or separated, where required, with resulting solid and liquid fractions temporarily contained pending removal from the site. Solid material arising from the screening/separation process will be transferred to an appropriately authorised recovery or disposal facility, while liquid material will be transferred off site to an authorised wastewater treatment facility. The proposed maximum annual waste intake is 2,000 tonnes per annum. The revised Further Information layout identifies the principal operational building as the Debris Reception Building, with an approximate floor area of 192 m². Waste reception, unloading/decanting, debris handling and screening/separation activities will be undertaken within this enclosed building rather than as open-yard processing. The principal activities with the potential to generate odour include:  opening and unloading of vehicles or trailers within the Debris Reception Building;  tanker connection and disconnection;  waste decanting;  debris handling and screening/separation;  temporary handling and storage of screened solids;  storage-tank headspace emissions; REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 8  washdown and drainage activities;  opening of roller-shutter doors for essential vehicle access; and  abnormal events such as spills, equipment malfunction or interruption of the extraction system. During normal operation, the potentially odorous activities will be undertaken within the enclosed Debris Reception Building and subject to controlled mechanical extraction. Extracted foul air from the process area and associated controlled sources will be routed to the proposed odour-control unit for treatment prior to discharge to atmosphere through the designated controlled emission point A1. Accordingly, A1 is assessed as the principal controlled atmospheric emission source during normal operation. Potential short-duration fugitive emissions associated with essential door opening, vehicle movements or abnormal loss of containment are not treated as continuous normal-operating emission sources. These potential emissions will instead be controlled through building enclosure, maintenance of negative pressure during odorous operations, closed-door management, waste-handling procedures, spill controls and the measures specified within the Odour Management Plan. Figure 1.0 (A). Revised Further Information site layout showing the Debris Reception Building area, odour scrubber system, covered tanks and proposed new biofilter unit. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 9 Figure 1 (B) - Debris Reception Building - proposed plan, elevations and section; floor area approximately 192 m2. Figure 1 (C) - Proposed new biofilter unit showing the modular treatment unit, associated fan/ductwork and two 1.5 m3 sumps. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 10 3.0 ODOUR CONTROL SYSTEM 3.1 Proposed Abatement Arrangement The proposed odour-control strategy is based on the containment, capture and treatment of potentially odorous air arising from the proposed waste-processing activities. Waste reception, unloading/decanting, debris handling, screening/separation and associated temporary handling activities will be undertaken within the enclosed Debris Reception Building. The building will be provided with controlled mechanical extraction to capture potentially odorous air and maintain the process area under negative pressure during odorous operations. Foul air extracted from the Debris Reception Building, together with controlled air arising from associated tank/storage sources, will be routed to the proposed Anua Clean Air Dual-Pass Monashell Odour Control Unit (OCU), or equivalent approved system, for treatment prior to discharge to atmosphere. The revised site layout identifies the proposed odour scrubber/biofilter arrangement. The reference OCU configuration comprises two treatment stages, duty/standby extraction fans and a vertical final discharge to atmosphere. For the purposes of the air dispersion assessment, the treated vertical OCU exhaust is designated Emission Point A1 and represents the principal controlled atmospheric emission source associated with normal operation of the proposed development. 3.2 Monashell Technology Monashell is an enhanced biofiltration technology developed for the treatment of odorous air arising from wastewater treatment, sludge handling, municipal waste, composting and other industrial processes. The technology uses biologically active filtration media to remove odorous compounds from extracted air prior to discharge. Supplier information identifies the system as being suitable for the treatment of compounds including reduced sulphur compounds, other odorous organic compounds and volatile organic compounds. The proposed arrangement incorporates a dual-stage treatment configuration, providing sequential treatment of the extracted foul-air stream prior to final discharge through A1.The final OCU will be operated and maintained in accordance with the manufacturer's requirements to ensure that the treated outlet concentration remains within the performance envelope adopted within this assessment. 3.3 OCU Design and Emission Parameters Table 3.1 OCU Design and Emission Parameters Parameter Adopted / Reference Value Basis OCU type Dual-Pass Monashell / equivalent dual-stage OCU Anua reference configuration Total foul-air flow 4,000 m3/hr (1.111 m3/s) Building ventilation assessment Approximate building volume 950 m³ 192 m² floor area × approx. 4.95 m average height Approximate air- change rate 4.2 ACH 4,000 m³/hr ÷ 950 m³ REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 11 Parameter Adopted / Reference Value Basis Fan arrangement Duty/standby Reference OCU arrangement Vent stack height 7.45m Proposed OCU arrangement* Terminal outlet diameter 0.240 m Proposed/reference arrangement Calculated exit velocity 24.6 m/s Calculated from 1.111 m3/s and 0.240 m outlet Outlet temperature Ambient Conservative assessment assumption Controlled emission point A1 - Biofilter/OCU exhaust discharge Proposed development A1 coordinates (ITM) E 683929, N 803346 Confirmed source location A1 coordinates (Irish Grid) E 283986, N 303328 Confirmed source location A1 coordinates (WGS84) 53.972581 N, -6.720686 W Confirmed source location The controlled atmospheric discharge assessed within this report is therefore Emission Point A1 at ITM E 683929, N 803346. 3.4 Ventilation Design Basis The Debris Reception Building has an approximate floor area of 192 m². Based on the revised building elevations, an indicative average enclosed height of approximately 4.95 m has been adopted, providing an estimated internal volume of approximately 950 m³. The Northern Ireland Water Wastewater Non-Infrastructure Asset Standard – Volume 13: Odour Management has been used as a technical design benchmark for ventilation of enclosed potentially odorous processes. The guidance recommends a minimum ventilation rate of approximately four air changes per hour (ACH) for buildings containing potentially odorous activities and the maintenance of negative pressure to minimise uncontrolled escape of odorous air. For an estimated building volume of approximately 950 m³, four air changes per hour corresponds to an extraction requirement of approximately: 950 m³ × 4 ACH = 3,800 m³/hr A nominal design extraction rate of 4,000 m³/hr, equivalent to approximately 4.2 air changes per hour, has therefore been adopted for this assessment. This provides a margin above the minimum whole-building ventilation benchmark. The NI Water standard is used as a technical design benchmark rather than as a statutory requirement applicable to the Monaghan site. The extraction system will be configured to maintain the Debris Reception Building under negative pressure during potentially odorous operations, including tanker connection and decanting, unloading, debris handling, screening/separation and temporary handling of screened material. Where local extraction or process capture requires an airflow greater than the nominal whole-building ventilation rate, the greater extraction duty shall govern.The OCU and extraction system will be commissioned following installation to verify airflow, system balance, negative-pressure performance and treated outlet performance. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 12 3.5 OCU Performance and Air Dispersion Assessment Basis The air dispersion assessment requires a defined treated odour concentration and corresponding odour emission rate for the proposed controlled OCU discharge. As a comparative design precedent, the AWN Consulting odour-modelling assessment undertaken for McBreen Environmental, Co. Cavan considered biofilter performance information indicating typical odour-removal efficiencies of approximately 90–98% for inlet concentrations in the range of approximately 5,000– 20,000 OUE/m³. The McBreen assessment adopted a post-treatment outlet concentration of 500 OUE/m³ for dispersion modelling purposes. Although the McBreen assessment adopted 500 OUE/m³ as a post-treatment modelling value, a lower maximum normal- operating design target of 400 OUE/m³ is adopted for the proposed JC Environmental OCU. This lower target provides an additional compliance margin at the closest residential receptors under the conservative Gaussian screening methodology. The McBreen value of 500 OUE/m³ is retained as a sensitivity case rather than as the normal operating design target. Unlike a passive surface biofilter, the proposed JC Environmental arrangement comprises a mechanically extracted air stream discharged through a defined outlet. The odour emission rate can therefore be calculated directly from the treated outlet concentration and the design airflow. At a design airflow of 4,000 m³/hr, equivalent to 1.111 m³/s, an outlet concentration of 400 OUE/m³ gives an odour emission rate of approximately: 400 OUE/m³ × 1.111 m³/s = 444 OUE/s Supplier information for the Anua Dual-Stage Monashell system provides an additional performance reference. Cavan Town WWTP installation involved dual-stage Monashell OCUs treating approximately 6,700 m³/hr with a reported inlet concentration of approximately 50,000 OUE/m³ and approximately 98% odour removal. A 98% reduction from an inlet concentration of 50,000 OUE/m³ corresponds to an indicative treated outlet concentration of approximately 1,000 OUE/m³. This supplier information is retained as a reduced-performance sensitivity benchmark; it does not represent the proposed normal operating condition for JC Environmental. The assessment therefore adopts 400 OUE/m³ as the maximum normal-operating design target, with 500 OUE/m³, 1,000 OUE/m³ and 2,000 OUE/m³ assessed as progressively deteriorated-performance sensitivity cases. A no-abatement case is retained solely as an abnormal failure sensitivity. Table No 3.2. OCU Design and Odour Emission Scenarios Model case Outlet concentration OCU flow Odour emission rate S1 - Design target 400 OUE/m3 1.111 m3/s 444 OUE/s S2 - Sensitivity case 500 OUE/m3 1.111 m3/s 556 OUE/s S3 - Reduced performance 1,000 OUE/m3 1.111 m3/s 1,111 OUE/s S4 - Severe reduced performance 2,000 OUE/m3 1.111 m3/s 2,222 OUE/s S5 - No-abatement sensitivity 50,000 OUE/m3 1.111 m3/s 55,556 OUE/s REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 13 4.0 ASSESSMENT CRITERIA 4.1 Odour Criterion EPA Guidance Note AG4, Appendix H, provides indicative odour assessment criteria having regard to the relative offensiveness of different odour sources. Processes involving septic effluent or sludge, together with waste-related activities including waste transfer operations, fall within the more offensive odour category. For such activities, an indicative assessment criterion of: 1.5 OUE/m³ as the 98th percentile of hourly average concentrations is identified for assessment at sensitive receptors. A criterion of 1.5 OUE/m³ as the 98th percentile of hourly averages has therefore been adopted for the present assessment. The criterion is considered appropriately conservative having regard to the nature of the waste streams proposed to be handled and the presence of nearby residential receptors. The assessment therefore examines whether predicted odour concentrations associated with the controlled OCU discharge remain below 1.5 OUE/m³ at sensitive receptor locations during normal operation. 4.2 Background and Cumulative Odour The assessment of odour differs from that applied to conventional pollutants where a numerical ambient background concentration may be added directly to a modelled process contribution. EPA AG4 notes that the direct addition of a measured ambient odour concentration to a predicted modelled odour concentration is not generally an appropriate method of assessing cumulative odour effects. Background odour conditions are therefore considered through identification of existing odour sources, field observations, source characterisation, complaint information and consideration of the circumstances under which different odour sources may affect the same receiving environment. Three operational piggeries have been identified within the immediate surrounding area of the JC Environmental site. The approximate populations provided are:  B1 – approximately 1,500 pigs;  B2 – approximately 250 pigs; and  B3 – approximately 250 pigs. This represents an approximate combined population of 2,000 pigs. These livestock facilities constitute identifiable and pre-existing potential sources of livestock- and manure-related odour within the local receiving environment. They operate independently of the proposed JC Environmental activity and are therefore relevant to the characterisation of existing background odour conditions. The three livestock facilities are considered as identified background and cumulative odour sources and are taken into account when interpreting existing ambient odour conditions, field observations and any odour complaints arising within the surrounding area. The meteorological review for the selected Ballyhaise dataset identifies a predominantly south-westerly wind sector during the assessment period and a south-westerly prevailing wind for each of the five years. Accordingly, the occurrence of odour within the surrounding area should not automatically be attributed to a single source. Where odour observations or complaints arise, source attribution should have regard to:  wind direction and prevailing meteorological conditions;  the location of the receptor relative to identified potential sources;  odour character; REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 14  odour intensity;  persistence and frequency;  the operating status of the JC Environmental facility at the time; and  the presence and operation of other identifiable odour sources. Tabel No 3.3. Identified Background Odour Sources and Assessment Treatment ID Background source Approx. pig population Treatment within assessment B1 Piggery 1 1,500 Identified as a separate existing livestock/manure odour source; B2 Piggery 2 250 Identified as a separate existing livestock/manure odour source; B3 Piggery 3 250 Identified as a separate existing livestock/manure odour source; Total Three piggeries 2,000 Considered as material existing background/cumulative odour sources REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 15 5.0 SENSITIVE RECEPTORS 5.1 Receptor Context Residential properties occur in a number of directions around the application site and are treated as high-sensitivity receptors for the purposes of the odour assessment. The controlled OCU discharge point, designated A1, is located at ITM E 683929, N 803346. The receptor assessment has been undertaken relative to this defined emission point. The closest identified residential receptors occur to the north, east and south-east of A1. These properties represent the locations at which potential off-site odour impacts associated with the proposed development require particular consideration. The three nearby piggeries identified as B1, B2 and B3 are existing background odour sources rather than sensitive receptors. Their approximate pig populations are 1,500, 250 and 250 animals respectively and they are considered separately within Section 4.2 in the assessment of background and cumulative odour conditions. The residential receptors adopted for the assessment are summarised in Table 5.1. Table 5.1 – Odour-Sensitive Residential Receptors ID Receptor Irish Grid Coordinates Approx. Distance from A1 Direction from A1 Sensitivity R1 Nearest dwelling south- east E 283941, N 303264 84 m South-east High – Residential R2 Row of dwellings east E 284057, N 303352 67 m East High – Residential R3 Nearest dwelling north E 283955, N 303419 90 m North High – Residential R4 Dwellings north E 284003, N 303400 64 m North High – Residential The closest identified receptor is therefore R4 at approximately 64 m from A1, followed by R2 at approximately 67 m, R1 at approximately 84 m and R3 at approximately 90 m. Figure 2 – Sensitive receptor context showing controlled OCU discharge point A1 and identified residential receptors R1– R4. 5.2 Receptor Distance Assessment The separation distances between the controlled OCU discharge point A1 and the identified residential receptors have been determined from the adopted receptor coordinates. The receptor locations have been selected to represent the closest residential properties surrounding the application site and therefore provide a conservative basis for assessing potential odour impacts associated with the proposed controlled atmospheric discharge. The assessment focuses particularly on the nearest receptors within approximately 100 m of A1, as these locations represent the greatest potential for ground-level odour impacts from the controlled discharge. The following receptor distances are adopted within the air dispersion assessment:  R4 – 64 m;  R2 – 67 m;  R1 – 84 m; and  R3 – 90 m. The predicted odour concentrations presented in Section 7 are assessed against the adopted 1.5 OUE/m³ criterion at these sensitive receptor locations. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 16 Figure 2 - Illustrative sensitive receptor context with confirmed A1 OCU discharge location (ITM E 683929, N 803346). Assessment distances are based on the adopted receptor coordinates in Table 5.1. Figure 3.0 - Indicative distance bands from confirmed A1 OCU discharge (ITM E 683929, N 803346). REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 17 6.0 Dispersion Modelling Methodology 6.1 EPA AG4 Assessment Framework EPA Guidance Note AG4 provides the technical framework for the assessment of atmospheric emissions from industrial installations, including consideration of emission-source characteristics, meteorological conditions, sensitive receptors and appropriate assessment criteria. The present assessment has been prepared taking account of the relevant principles of AG4 applicable to the proposed controlled odour emission source. In particular, the assessment considers:  the location and physical characteristics of the controlled emission point;  the proposed treated odour concentration and corresponding emission rate;  discharge height, outlet diameter and vertical discharge velocity;  the character of the surrounding receiving environment;  nearby sensitive residential receptors;  representative meteorological conditions; and  the applicable odour assessment criterion. A conservative Gaussian dispersion screening methodology has been applied to assess potential ground-level odour concentrations arising from the proposed controlled OCU discharge, designated A1. The screening assessment evaluates a range of atmospheric stability and wind-speed conditions and adopts the highest calculated ground-level concentration at each receptor distance. The purpose of this approach is to provide a conservative assessment of the potential for off-site odour impacts under a range of dispersion conditions. Sensitivity testing has additionally been undertaken across a range of treated OCU outlet concentrations to demonstrate the influence of OCU performance on predicted ground-level concentrations. 6.2 Meteorological Dataset Review Meteorological conditions influence the transport and dispersion of atmospheric emissions and have therefore been considered as part of the assessment. Hourly meteorological records for Met Éireann Ballyhaise Station 675, located approximately 39 km west-north-west of the application site, were reviewed for the five complete calendar years 2021–2025. Year Hourly records Missing hours Mean wind speed Max wind speed Calm hours <0.3 m/s Prevailing sector 2021 8,760 0 2.88 m/s 11.83 m/s 4 SW 2022 8,760 0 3.10 m/s 10.29 m/s 6 SW 2023 8,760 0 3.00 m/s 9.77 m/s 2 SW 2024 8,784 0 3.03 m/s 14.40 m/s 2 SW 2025 8,760 0 3.02 m/s 16.46 m/s 2 SW The Ballyhaise dataset comprises 43,824 hourly records over the five-year period and contains no missing hourly wind- speed or wind-direction records. Mean annual wind speeds range from approximately 2.88 to 3.10 m/s, while the prevailing wind sector is south-westerly in each of the five years reviewed. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 18 The meteorological review indicates a relatively consistent wind regime across the assessment period. The south-westerly prevailing sector has also been considered in the interpretation of potential odour transport between the application site, surrounding residential receptors and existing background odour sources. Figure 4. Combined Ballyhaise wind rose for the selected 2021-2025 meteorological period. 6.3 Gaussian Dispersion Screening Model A Gaussian plume screening model has been applied to assess the potential ground-level odour concentrations associated with the proposed controlled OCU discharge. The model assesses the principal controlled atmospheric emission source, A1, and evaluates rural Pasquill-Gifford atmospheric stability classes A to F across wind speeds ranging from 1 to 10 m/s. For each receptor distance, the highest calculated centreline ground-level concentration arising from the tested combinations of stability class and wind speed is adopted for assessment purposes. This approach intentionally examines a broad range of potential dispersion conditions rather than relying on a single assumed meteorological condition. The proposed waste reception, unloading/decanting, debris handling and screening/separation activities will be undertaken within the enclosed Debris Reception Building under controlled extraction. Accordingly, the treated OCU exhaust at A1 is assessed as the principal continuous controlled atmospheric emission source during normal operation. Potential short-duration fugitive emissions associated with essential door opening, vehicle access or abnormal events are controlled through enclosure, maintenance of negative pressure, closed-door management and the operational measures specified within the Odour Management Plan and are not represented as separate continuous emission sources. The Gaussian screening equation applied is: C = [Q / (π × u × σy × σz)] × exp[-H² / (2σz²)] where:  C = predicted ground-level odour concentration; REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 19  Q = odour emission rate, OUE/s;  u = wind speed, m/s;  σy = horizontal dispersion coefficient;  σz = vertical dispersion coefficient; and  H = physical release height. For the proposed development, the principal assessment parameters are:  Emission source: A1;  Stack height: 7.45 m;  Outlet diameter: 0.240 m;  Design airflow: 4,000 m³/hr (1.111 m³/s);  Calculated vertical exit velocity: 24.6 m/s; and  Primary treated outlet concentration: 400 OUE/m³, corresponding to approximately 444 OUE/s. The screening calculation adopts the 7.45 m physical stack height. No additional numerical credit is taken within the Gaussian screening calculation for plume rise associated with the relatively high vertical discharge velocity. This provides a conservative treatment of the release within the limitations of the screening methodology. The assessment considers the identified residential receptors at approximately 64 m, 67 m, 84 m and 90 m from A1, as set out in Section 5. The calculated concentrations are compared with the adopted 1.5 OUE/m³ assessment criterion. As the screening model identifies conservative maximum ground-level concentrations rather than generating a site-specific hourly percentile distribution, the results are used as a conservative screening comparison against the 1.5 OUE/m³ benchmark. 6.4 Source Term The controlled emission source assessed within the dispersion model is A1, located at ITM E 683929, N 803346. The adopted whole-building extraction rate is 4,000 m³/hr, equivalent to 1.111 m³/s. This extraction duty is based on the ventilation requirements of the enclosed Debris Reception Building and represents approximately 4.2 air changes per hour for the estimated building volume. The primary assessment scenario adopts a treated OCU outlet concentration of 400 OUE/m³. The corresponding odour emission rate is calculated directly from the treated outlet concentration and volumetric airflow:  Odour emission rate = outlet concentration × airflow  400 OUE/m³ × 1.111 m³/s = approximately 444 OUE/s A 500 OUE/m³ outlet concentration is assessed as a sensitivity case and corresponds to an odour emission rate of approximately 556 OUE/s. Additional reduced-performance scenarios have been assessed at treated outlet concentrations of 1,000 OUE/m³ and 2,000 OUE/m³, together with an abnormal no-abatement sensitivity case of 50,000 OUE/m³. The adopted source terms are therefore:  400 OUE/m³ = 444 OUE/s;  500 OUE/m³ = 556 OUE/s;  1,000 OUE/m³ = 1,111 OUE/s;  2,000 OUE/m³ = 2,222 OUE/s; and REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 20  50,000 OUE/m³ = 55,556 OUE/s. These source terms are calculated directly using the adopted 4,000 m³/hr extraction rate. The 400 OUE/m³ design target corresponds to the maximum normal-operating treated outlet concentration used in the compliance screening assessment. The physical release parameters adopted within the assessment comprise a 7.45 m high vertical discharge stack, a terminal outlet diameter of 0.240 m and a calculated exit velocity of approximately 24.6 m/s. The model represents normal operation on the basis that potentially odorous activities are undertaken within the enclosed Debris Reception Building under controlled extraction, with extracted foul air routed through the OCU prior to discharge through A1. The three nearby piggeries identified as B1–B3 are recognised separately as existing background odour sources in accordance with Section 4.2. No arbitrary numerical emission rate has been assigned to those sources. 6.5 Model Scenarios A series of operating and sensitivity scenarios has been assessed to determine the relationship between OCU treatment performance and potential ground-level odour concentrations at surrounding sensitive receptors. The assessment scenarios are summarised in Table 6.1. Table 6.1.Assessment scenarios Scenario Purpose Source term S1 - Design target 400 OUE/m3 maximum normal-operating design target 444 OUE/s S2 - Sensitivity case 500 OUE/m3 deterioration sensitivity 556 OUE/s S3 - Reduced-Performance Sensitivity 1,000 OUE/m3 reduced-performance sensitivity 1,111 OUE/s S4 - Severe Reduced- Performance Sensitivity 2,000 OUE/m3 severe deterioration sensitivity 2,222 OUE/s  Scenario S1 represents the proposed maximum normal-operating design case for the odour-control system.  Scenario S2 is retained as a sensitivity case to demonstrate the consequence of deterioration above the 400 OUE/m³ design target.  Scenario S3 represents reduced OCU performance and is included to assess the sensitivity of predicted concentrations to a more substantial deterioration in treatment efficiency.  Scenario S4 represents severe deterioration in treatment performance and is included solely as a sensitivity test. It is not regarded as an acceptable normal operating condition. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 21 6.6 Building Effects and Stack Height The proposed OCU treated-air discharge is via a 7.45 m high vertical stack located at Emission Point A1. The revised stack arrangement provides a substantially elevated discharge relative to the previously considered lower-level configuration and is intended to promote effective dispersion of the treated exhaust above the immediate process area. The proposed stack has a terminal outlet diameter of 0.240 m. At the adopted extraction airflow of 4,000 m³/hr (1.111 m³/s), the calculated vertical discharge velocity is approximately 24.6 m/s. This discharge velocity exceeds the 15 m/s efflux-velocity benchmark referenced within the NI Water Odour Management technical standard used as a design benchmark for this assessment. The combination of:  a 7.45 m vertical discharge height;  a 0.240 m terminal outlet;  an exit velocity of approximately 24.6 m/s; and  vertical discharge of the treated air stream provides improved initial dispersion and reduces the potential for immediate recirculation of treated exhaust in the vicinity of the OCU and Debris Reception Building. The Gaussian screening assessment adopts the 7.45 m physical release height for A1. No additional numerical credit is taken for plume rise associated with the high vertical exit velocity. The screening methodology does not explicitly calculate building-wake effects using a detailed building-downwash model. The revised elevated vertical discharge configuration has therefore been selected as a practical design measure to minimise the potential influence of the adjacent building on dispersion of the treated exhaust. 7.0 Screening Results The Gaussian dispersion screening model described in Section 6 has been applied using the revised physical and emission characteristics of Emission Point A1, including the 7.45 m stack height, 0.240 m outlet diameter, 4,000 m³/hr extraction airflow and the source terms identified in Section 6.4. Concentrations have been assessed for the 400 OUE/m³ design target, 500 OUE/m³ sensitivity case, 1,000 OUE/m³ reduced-performance sensitivity case and 2,000 OUE/m³ severe reduced-performance sensitivity case. The predicted ground-level concentrations are compared with the adopted 1.5 OUE/m³ odour benchmark. Table 7.1 Predicted Ground-Level Odour Concentrations for Design and Reduced-Performance Scenarios Distance Design 400 Sensitivity 500 Reduced 1,000 Severe 2,000 Criterion 60 m 1.33 1.66 3.32 6.64 1.50 75 m 1.32 1.65 3.30 6.60 1.50 100 m 1.31 1.64 3.28 6.56 1.50 125 m 1.15 1.44 2.88 5.76 1.50 150 m 0.96 1.20 2.40 4.80 1.50 200 m 0.89 1.11 2.22 4.44 1.50 250 m 0.78 0.97 1.94 3.88 1.50 300 m 0.65 0.81 1.62 3.24 1.50 400 m 0.67 0.84 1.68 3.36 1.50 500 m 0.58 0.73 1.46 2.92 1.50 600 m 0.49 0.61 1.22 2.44 1.50 REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 22 7.1 Concentration with Distance Figure 5. Gaussian screening concentration versus distance from confirmed A1 OCU discharge for the 7.45 m stack configuration. The 400 OUE/m³ design target remains below the adopted 1.5 OUE/m³ screening benchmark throughout the assessed distance range from 60 m to 600 m. At 60 m, the predicted design-case concentration is approximately 1.33 OUE/m³, reducing generally with distance. The 500 OUE/m³ sensitivity case exceeds the screening benchmark at the nearest assessed distances but falls below it by approximately 125 m. The 1,000 OUE/m³ and 2,000 OUE/m³ cases represent reduced-performance sensitivities and demonstrate the importance of maintaining the OCU at or below the 400 OUE/m³ normal-operating design target. 7.2 Residential Receptor Results Table 7.2 Residential Receptor Results Receptor Distance 400 OUE/m³ Design Case Criterion Result R4 64 m 1.36 1.50 Below R2 67 m 1.36 1.50 Below R1 84 m 1.30 1.50 Below R3 90 m 1.32 1.50 Below Receptor concentrations are expressed as OUE/m³. Emission Point A1 is fixed at ITM E 683929, N 803346 and the adopted receptor distances are those set out in Table 5.1: R4 at 64 m, R2 at 67 m, R1 at 84 m and R3 at 90 m. Under the 400 OUE/m³ design case, all four identified residential receptors remain below the adopted 1.5 OUE/m³ screening benchmark. Predicted concentrations are approximately 1.36 OUE/m³ at R4 and R2, 1.30 OUE/m³ at R1 and 1.32 OUE/m³ at R3. By comparison, the 500 OUE/m³ sensitivity case would be above the benchmark at the nearest receptors, confirming that 400 OUE/m³ should be treated as the maximum normal-operating outlet concentration for the proposed OCU. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 23 7.3 Design-Target Screening Envelope Figure 6.0 - 400 OUE/m³ design-target radial screening envelope centred on confirmed A1 discharge (illustrative screening output). 7.4 Reduced-Performance Sensitivity Envelope Figure 7.0 - 2,000 OUE/m³ severe reduced-performance sensitivity envelope centred on confirmed A1 discharge (illustrative screening output). REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 24 7.5 Interpretation The screening assessment demonstrates that predicted ground-level odour concentrations are strongly influenced by both OCU treatment performance and receptor proximity. The proposed development incorporates a controlled odour-management strategy based on enclosure of potentially odorous activities within the Debris Reception Building, maintenance of negative pressure, mechanical extraction of foul air and treatment through the proposed OCU prior to vertical discharge through Emission Point A1. The assessment adopts a 7.45 m high vertical discharge stack, an extraction airflow of 4,000 m³/hr, a terminal outlet diameter of 0.240 m and a calculated vertical exit velocity of approximately 24.6 m/s. The conservative Gaussian screening methodology evaluates a broad range of atmospheric stability classes and wind speeds and adopts the highest calculated ground-level concentration at each receptor distance. No additional numerical credit is taken for plume rise associated with the relatively high vertical discharge velocity. The results therefore represent a deliberately conservative screening assessment of the proposed controlled source. The assessment identifies the nearest residential receptors, located approximately 64–90 m from A1, as the controlling receptor locations. Under the 400 OUE/m³ design-target scenario, the conservative screening assessment predicts concentrations below the adopted 1.5 OUE/m³ screening benchmark at all four identified residential receptors. The nearest receptors are predicted at approximately 1.30-1.36 OUE/m³, providing a measurable margin below the screening benchmark. The 500 OUE/m³ sensitivity case demonstrates that deterioration above the proposed design target could result in exceedance of the screening benchmark at the nearest receptors. The OCU shall therefore be selected, commissioned, operated and maintained to achieve a treated outlet concentration of 400 OUE/m³ or lower during normal operation. Overall, the assessment confirms that the effectiveness of the proposed odour-control strategy is dependent upon:  effective enclosure of potentially odorous activities;  maintenance of negative pressure within the Debris Reception Building;  reliable operation of the proposed OCU;  maintenance of a treated outlet concentration at or below the design performance target;  use of the proposed 7.45 m vertical discharge stack; and  implementation of the operational controls set out in Section 8. 8.0 Mitigation and Operational Controls The following mitigation and operational controls shall be incorporated into the detailed design, commissioning and operation of the proposed development and into the site Odour Management Plan.  All waste reception, unloading, decanting, debris handling, screening/separation and temporary waste-holding activities with the potential to generate odour shall be undertaken within the enclosed Debris Reception Building.  The Debris Reception Building shall be maintained under negative pressure during potentially odorous operations to minimise uncontrolled fugitive emissions from doors and other openings.  A minimum nominal whole-building extraction duty of 4,000 m³/hr, equivalent to approximately 4.2 air changes per hour, shall be provided, subject to verification during detailed OCU design and commissioning.  Foul air from the Debris Reception Building and relevant tank/storage headspace sources shall be captured and routed through the proposed odour-control unit prior to discharge to atmosphere.  The treated exhaust shall be discharged vertically through the proposed 7.45 m high stack at Emission Point A1.  The OCU shall be designed and operated to achieve a treated outlet odour concentration of 400 OUE/m³ or lower during normal operation. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 25  The OCU supplier shall provide appropriate performance information demonstrating that the selected system is capable of achieving the specified treated outlet performance under the anticipated loading conditions.  Duty/standby extraction fans shall be provided, together with appropriate fault indication and automatic changeover where practicable, to minimise interruption to foul-air extraction.  Waste reception, unloading, decanting and screening activities shall be suspended where the extraction or OCU system is unavailable and effective odour containment cannot be maintained.  Roller-shutter and personnel doors shall remain closed during potentially odorous operations except where opening is necessary for vehicle or personnel access.  Vehicle entry and exit procedures shall be managed to minimise the duration for which roller-shutter doors remain open.  Waste-retention periods shall be minimised, and screened solids and other potentially odorous materials shall be removed from the site as soon as reasonably practicable.  Tanks containing potentially odorous liquids shall remain covered, and waste-transfer connections shall be maintained as closed or vapour-tight systems insofar as practicable.  Routine housekeeping shall include prompt removal of residues, regular washdown of relevant process areas, cleaning of drainage channels and immediate clean-up of spills.  The OCU, extraction system and associated ductwork shall be subject to a planned preventative maintenance programme.  Prior to routine operation, the extraction and odour-control system shall be commissioned to confirm airflow, system balance, negative-pressure performance and treated outlet performance.  Commissioning shall verify that the actual extraction airflow is consistent with the 4,000 m³/hr design basis and that OCU performance is consistent with the treated outlet concentration adopted within this assessment.  Following commissioning, periodic performance checks shall be undertaken in accordance with the manufacturer's recommendations and the site's Odour Management Plan.  A site odour complaints register shall be maintained. Complaints shall be recorded together with the date, time, prevailing meteorological conditions, operational status of the facility and, where possible, the character and likely source of the reported odour.  Routine boundary odour assessments shall be undertaken at defined monitoring locations during representative operating conditions.  Field odour assessments shall have regard to the principles of EPA AG5, including odour character, intensity, persistence, frequency and likely source.  Particular attention shall be given to distinguishing, insofar as reasonably practicable, livestock/manure-related odour from B1–B3 from wastewater/septic/debris-type odour potentially associated with JC Environmental.  Where a substantiated odour issue associated with the site is identified, corrective action shall be undertaken promptly. Corrective measures may include review of OCU performance, increased extraction, maintenance or replacement of treatment media, amendment of operating procedures or temporary suspension of the relevant odour-generating activity. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 26 9.0 Conclusions The following conclusions are drawn from the Odour Impact Assessment and Air Dispersion Assessment undertaken for the proposed development at Mullanarry, Carrickmacross, Co. Monaghan:  The application site is located within a mixed receiving environment comprising agricultural lands, residential properties and estates, commercial development and the urban edge of Carrickmacross. The surrounding environment is therefore not characterised as predominantly agricultural for the purposes of this assessment.  Nearby residential properties have been treated as high-sensitivity receptors. The closest identified residential receptors are located approximately 64–90 m from the controlled OCU discharge point A1.  The proposed waste reception, unloading/decanting, debris handling, screening/separation and associated temporary handling activities will be undertaken within the enclosed Debris Reception Building, which has an approximate floor area of 192 m².  The proposed odour-control strategy is based on enclosure of potentially odorous operations, maintenance of the Debris Reception Building under negative pressure, controlled mechanical extraction of foul air and treatment through the proposed OCU prior to discharge to atmosphere through Emission Point A1.  Three operational piggeries have been identified within the surrounding area, with approximate populations of 1,500, 250 and 250 pigs respectively, representing an approximate combined population of 2,000 pigs. These facilities constitute identifiable pre-existing sources of livestock/manure-related odour and are relevant to the interpretation of existing ambient odour conditions and complaints.  An odour assessment benchmark of 1.5 OUE/m³ has been adopted having regard to the indicative EPA AG4 Appendix H criterion applicable to relatively offensive odour sources. The Gaussian screening concentrations are compared against this value as a conservative screening benchmark.  The proposed OCU design basis comprises a nominal extraction airflow of 4,000 m³/hr (1.111 m³/s), equivalent to approximately 4.2 air changes per hour for the estimated 950 m³ enclosed building volume.  The proposed controlled discharge at A1 comprises a 7.45 m high vertical stack with a terminal outlet diameter of 0.240 m. At the adopted airflow of 4,000 m³/hr, the calculated vertical discharge velocity is approximately 24.6 m/s.  The primary OCU design target adopted for assessment is a treated outlet concentration of 400 OUE/m³, corresponding to an odour emission rate of approximately 444 OUE/s. A 500 OUE/m³ sensitivity case, corresponding to approximately 556 OUE/s, has also been assessed together with reduced-performance sensitivity scenarios.  The air dispersion assessment has been undertaken using a conservative Gaussian screening methodology, taking account of the relevant principles of EPA AG4. The model considers a range of atmospheric stability conditions and wind speeds and adopts the highest calculated ground-level concentration at each assessed distance.  The results demonstrate that the nearest residential receptors represent the controlling locations for assessment. Under the 400 OUE/m³ design-target scenario, predicted concentrations at all four identified residential receptors remain below the adopted 1.5 OUE/m³ benchmark, with predicted values ranging from approximately 1.30 to 1.36 OUE/m³.  The assessment therefore demonstrates the importance of maintaining the OCU at a consistently high level of treatment performance. The 400 OUE/m³ treated outlet concentration is adopted as the maximum normal- operating design target, and the installed OCU shall be selected, commissioned and maintained to achieve 400 OUE/m³ or lower during normal operation. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 27  Five complete years of hourly meteorological data for 2021–2025 from Met Éireann Ballyhaise Station have been reviewed. The records indicate mean annual wind speeds of approximately 2.88–3.10 m/s and a predominantly south-westerly wind sector in each of the five years.  The proposed development incorporates a range of operational controls including negative-pressure operation of the Debris Reception Building, closed-door management, controlled foul-air extraction, duty/standby extraction arrangements, minimisation of waste-retention periods, covered tanks, spill controls, preventative maintenance and routine odour monitoring.  Waste reception and processing operations shall be suspended where the extraction or OCU system is unavailable and effective odour containment cannot be maintained.  The proposed extraction and OCU system shall be commissioned prior to routine operation to verify extraction airflow, system balance, negative-pressure performance and treated outlet odour performance against the design basis adopted within this assessment.  Routine boundary odour assessments and complaint-response investigations shall be undertaken having regard to EPA AG5 principles. Odour character, intensity, persistence, meteorological conditions and the presence of other potential sources shall be considered when determining the likely source of any reported odour.  Subject to implementation of the proposed enclosure, extraction, treatment, commissioning, maintenance and operational controls, the proposed OCU arrangement provides an appropriate engineering basis for the management and control of odour associated with the proposed waste-processing activities. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 28 REFERENCES Monaghan County Council (10 December 2025), Further Information Request, Planning Ref. 25/60416. Traynor Environmental Ltd. (16 October 2025), Odour Management Plan – Mullanarry Environmental T/A JC Environmental. CMD Architects (3 October 2025), Site Location Plan, Drawing 21-146 0-01. Environmental Protection Agency (2019), Air Dispersion Modelling from Industrial Installations Guidance Note AG4, including Appendix H – Odour Modelling. Environmental Protection Agency, Air Guidance Note AG5 – Odour Impact Assessment Guidance for EPA Licensed Sites. Anua Clean Air International, JOB-24479 – Glanua, Kenmare WWTP – OCU3 – Monashell OCU 7 × 2 × 2 Dual Stage / Monashell OCU Drawings, reference design supplied. Anua Clean Air International, Monashell Generic Presentation, including Cavan Town WWTP case study. Traynor Environmental Ltd. (13 October 2025), Site Operation and Proposed Works – Mullanarry Environmental T/A JC Environmental. Anua Clean Air UK Ltd. (25 February 2025), QT-256105 – Lac Patrick Limited OCU Media & Unit Upgrade, Strabane Waste Water Treatment Plant. AWN Consulting Ltd. (28 July 2015), Odour Modelling Assessment for McBreen Environmental, County Cavan, Ref. SMcM/15/8415AR01. Met Éireann, Ballyhaise Station 675, hourly meteorological datasets for calendar years 2020–2025; 2021–2025 reviewed for the present assessment. Client-supplied information (14 September 2026) confirming three operational piggeries in the vicinity of JC Environmental, with approximate pig populations of 1,500, 250 and 250 respectively. Client-supplied coordinate confirmation for A1 OCU discharge, dated 12 September 2026: ITM E 683929, N 803346; Irish Grid E 283986, N 303328; WGS84 53.972581° N, -6.720686° W. CMD Architects, revised Further Information Site Layout Plan, Job 21-146, Drawing 3.2FI_002.00, showing proposed odour- control system and biofilter/OCU unit, revised 20 August 2026. CMD Architects, Proposed Bio Filter Unit, Job 21-146, Additional Information drawing, supplied September 2026. CMD Architects, Debris Reception Building – Proposed Plan, Elevations and Section A-A, Job 21/146, Drawing 3.2FI_104.00, dated 14 September 2026. Northern Ireland Water (4 July 2016), Wastewater Non-Infrastructure Asset Standards, Volume 13: Odour Management, Version 1.1. Used as a technical ventilation and odour-control design benchmark. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 29 Appendix A - OCU Process Schematic REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 30 The following supplier drawing illustrates the reference dual-stage Monashell OCU configuration, including the treatment stages, associated ductwork, duty/standby extraction-fan arrangement and vertical treated-air discharge. The supplier drawing is included to illustrate the proposed odour-control technology and general process arrangement. For the purposes of the present assessment, the proposed Debris Reception Building has been assessed on the basis of a nominal whole-building extraction duty of 4,000 m³/hr, equivalent to approximately 4.2 air changes per hour, together with a controlled vertical discharge through Emission Point A1. The proposed assessment configuration comprises a 7.45 m high vertical discharge stack, a terminal outlet diameter of 0.240 m and a calculated discharge velocity of approximately 24.6 m/s at the adopted 4,000 m³/hr airflow. The supplier drawing should therefore be regarded as a reference illustration of the proposed OCU technology and treatment arrangement, while the site-specific design parameters adopted for the JC Environmental assessment are those specified within Sections 3 and 6 of this report. REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 31 APPENDIX B - MET ÉIREANN BALLYHAISE STATION REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 32 The meteorological review period is 2021-2025 using Met Éireann Ballyhaise Station 675. Annual and combined wind roses are included to characterise prevailing wind conditions and support interpretation of the Gaussian dispersion screening assessment. The plots are based on the supplied hourly wind-speed and wind-direction data. The hourly meteorological series is not input directly into the screening calculation; the screening model instead evaluates Pasquill-Gifford stability classes A-F and wind speeds from 1 to 10 m/s as described in Section 6.3. [4][11] Figure C1. Ballyhaise 2021 Figure C2. Ballyhaise 2022 Figure C3. Ballyhaise 2023 Figure C4. Ballyhaise 2024 Figure C5. Ballyhaise 2025 Figure C6. Ballyhaise 2021-2025 combined REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 33 Appendix C - Odour Sensitive Receptors and Site Boundary Monitoring Locations REC E I V E D : 1 6 / 0 9 / 2 0 2 6 Odour Impact Assessment &Air Dispersion Modelling 34 ID Receptor Irish Grid Coordinates (E, N) Approx. Distance from OCU Exhaust (A1) Direction from OCU Exhaust (A1) Sensitivity Notes R1 Nearest dwelling Southeast 283941, 303264 84m Southeast High Residential R2 Row of Dwellings East 284057, 303352 67m East High Residential R3 Nearest dwelling North 283955, 303419 90m North High Residential R4 Dwellings North 284003, 303400 64m North High Residential Figure A1: Odour-Sensitive Receptor Locations REC E I V E D : 1 6 / 0 9 / 2 0 2 6