Outline Corrective Action Summary

Transcription

1 Outline Corrective Action Summary Technical Note 20 October 2017

2 Quality information Prepared by Checked by Approved by Matteo Viganotti Senior Environmental Consultant David Mullan Associate Environmental Scientist David Mullan Associate Environmental Scientist Revision History Revision Revision date Details Authorized Name Position Issue 1 22/10/2017 Final 22/10/2017 Matteo Viganotti PM Prepared for:

3 Prepared for: Oldmilltown, Kill, Co. Kildare Prepared by: Matteo Viganotti Senior Environmental Consultant T: +353-(0) M: +353-(0) E: Ireland Limited 4th Floor Adelphi Plaza Georges Street Upper Co. Dublin Ireland T: aecom.com 2017 Ireland Limited. All Rights Reserved. This document has been prepared by Ireland Limited ( ) for sole use of our client (the Client ) in accordance with generally accepted consultancy principles, the budget for fees and the terms of reference agreed between and the Client. Any information provided by third parties and referred to herein has not been checked or verified by, unless otherwise expressly stated in the document. No third party may rely upon this document without the prior and express written agreement of. Prepared for:

4 Table of Contents 1. Introduction Background Scope Report Structure Licence Pt A Catchment Soil Contamination Hot-Spot (S1) Remedial Action Progress Sediment Contamination in Farmer s Pond (S2) Remedial Action Progress Stormwater Management Measures (S3 and S4) Progress Licence Pt E Catchment Soil Contamination Hot-Spot (S1) Remedial Action Progress Maintenance of the Exiting Drainage Pipework (S5) Remedial Action Progress Low Level Soil Contamination (S4 and S7) Remedial Action Progress Resurfacing of Critical Areas (P2 to P5) Remedial Action Progress Upgrading of Site Drainage Infrastructure (P2 to P8) Remedial Action Progress Upgrading of the Wastewater Treatment Plant (P2 to P8) Remedial Action Progress... 8 Appendix A Site Location Map... 9 Appendix B Licence Pt A Conceptual Site Model (CSM) Appendix C Licence Pt A Corrective Action Drawings Appendix D Licence Pt E Conceptual Site Model (CSM) Appendix E Licence Pt E Corrective Action Drawings Tables Table 1 Viable Source-Pathway-Receptor linkages Table 2 Viable Source-Pathway-Receptor linkages Prepared for:

5 1. Introduction Ireland Limited (hereafter referred to as ) is pleased to present Saint Gobain Building Distribution (ROI) Ltd., trading as PDM Limited (hereafter referred to as PDM ), with this Technical Note summarising the outline corrective action plan currently being implemented to address non-compliance issues at their site in Oldmilltown, Kill, Co. Kildare (the site). A location map of the site is provided in Appendix A. 1.1 Background PDM has operated under an Industrial Pollution Control Licence (Reg. No. P ), as issued by the Environmental Protection Agency (EPA), since A review of this licence was initiated by the EPA in 2011 for the purpose of fulfilling the requirements of the EC Environmental Objectives (Surface Waters) regulations PDM prepared and submitted a licence review application pack to the EPA in The rules surrounding this review process changed due to the transposition into Irish national law on 23rd April 2013 of the European Union (Industrial Emissions) Regulations 2013 (S.I. No. 138 of 2013). The EPA informed PDM in a notice issued on 12th November 2014 that their licence review application was subject to the EPA (Industrial Emission) (Licensing) Regulations The notice required PDM to furnish such information as is necessary for the application to comply with Regulation 13(2)(a) of the Regulations, and in particular to provide information as set out in the schedule attached to the notice. provided assistance to PDM in forming a response to the request for further information as set out in the notice, and this was submitted to the EPA on 1st May The EPA informed PDM in a notice issued on 24th June 2015 that further information pursuant to Section 90 of the EPA Acts was required in order to progress the licence review. A meeting was held between PDM and the EPA on 10th September 2015 during which the EPA requested that PDM complete relevant sections of the Industrial Emissions Activities Licence Application Form, in order to facilitate the provision of information to the EPA in order to progress the licence review. PDM completed the relevant sections of the Industrial Emissions Activities Licence Application Form and electronically submitted the information to the EPA on 20th November PDM are currently in the process of implementing environmental upgrade works across the site in response to Compliance Investigations CI000164, CI and CI It was agreed during a meeting between PDM, the EPA and in June 2016 that any further information requests would not be made until Quarter , once PDM had commissioned the infrastructural changes proposed for the site as part of the site environmental upgrade works. During a meeting at the PDM site on 24th May 2017 the EPA requested further information under Section 90 of the EPA Act as amended. This was submitted to the EPA on the 6 th September On the 29th September 2017, following the review of the documentation provided the EPA requested by the following additional information: 1. Details of the 2016 Outline Corrective Action Plans for emission point A and E and an update on the progress against same. 2. Monitoring results for emission point A and E for the last 6 months including a breakdown of the 16 PAHs and alkalinity readings. 1.2 Scope This Technical Note addresses Item 1 above and provides a summary of the 2016 Outline Corrective Action Plans 2,3 (CAP) prepared for the Licence Pt A and Licence Pt E catchment. These were developed to address exceedances recorded in discharges to surface water. Where relevant, amendments to the Outline Plans that occurred during detailed design development are also reported. Current progress in relation to the implementation of the corrective actions is also discussed. This document should be read in conjunction with the documents and information submitted to the EPA as discussed above. 1.3 Report Structure This report is organised in the following three (3) sections: 1 (2017), Response to EPA Request for Information dated 05/09/17 2 (2016), Outline Corrective Action Plan for Licence Pt A. Issue 1 3 (2016), Outline Corrective Action Plan for Licence Pt E. Issue 1 Prepared for: 1

6 1. Introduction; 2. Licence Pt A Catchment; 3. Licence Pt E Catchment. Sections 2 and Section 3 include a description of the identified viable Source-Pathway-Receptor (S-P-R) linkages. For each viable S-P-R linkage the proposed action to mitigate or eliminate impacts is outlined. A summary of current progress is provided for each action. 2. Licence Pt A Catchment Table 1 below summarises the viable S-P-R linkages considered to be present within the Licence Pt A catchment. These were determined on the basis of the Conceptual Site Model (CSM) developed for the site. A location map illustrating the viable S-P-R linkages is provided in Appendix B. Table 1 Viable Source-Pathway-Receptor linkages. Key Sources Potential Pathway Potential Receptors Hot spot soil contamination in the former reject pole storage area (S1) Contaminated sediment in Farmers Pond (S2). Low level contaminated soil across the subject area (including soil stockpiles) (S3). Treated product storage areas (S4). Contact with or ingestion of contaminated soil or dust (P1). Erosion and transport as an adsorbed phase on suspended particles or by dissolution into overland stormwater flow to Ditch 2 and emission at Licence Pt A (P2). Remobilisation of sediment during rainfall and transport as an adsorbed phase on suspended particles or by dissolution into stormwater flow to Ditch 2 and emission at Licence Pt A (P2). Erosion and transport as an adsorbed phase on suspended particles or by dissolution into the water column in overland stormwater flow to drainage ditches and emission at Licence Pt A (P2). Wind-blown contamination and incidental splashing into adjacent Ditch 2 and onward to Licence Pt A (P3). Workers on site (R1). Kill River, Killhill River and Painestown River (R2) The proposed outline strategy to address the S-P-R linkages identified above can be divided into two parts. 1. Source reduction measures associated with hot spot soil contamination giving rise to associated human health risk in the former Rejected Poles storage area (S1) and low level contaminated sediment in Farmers Pond (S2). 2. Stormwater management measures associated with low level soil contamination (PAHs) across the subject area (S3) and storage of treated timber adjacent to Ditch 2 (S4). Drawings detailing the proposed remedial actions for the Licence Pt A catchment are provided in Appendix C. 2.1 Soil Contamination Hot-Spot (S1) Remedial Action Two options were considered to address the hot spot soil contamination reported in the former Reject Poles storage area: 1. Excavation and disposal of contaminated soil; and 2. Containment / encapsulation of contaminated soil. Prepared for: 2

7 Of the two options considered, excavation and disposal scored the highest results in the remedial options assessment (83 compared to 80). Additionally, a high level of protection of surface water and a higher level of protection of groundwater would be provided by the excavation option in the general context of the site. The recommended remediation option was to excavate and dispose of an estimated area of 1,250m 2 in total, with contamination to a depth of 0.4m, representing a volume of 500m 3 of soil. The area was to be re-instated with clean materials for future use as storage area for untreated timber stock Progress These remediation works have been completed. 2.2 Sediment Contamination in Farmer s Pond (S2) Remedial Action Given the relatively small volume of sediment estimated in the pond, it was proposed to excavate and dispose of it appropriately offsite. The estimated volume of mildly contaminated material to be excavated was 25m 3. However, since the preparation of the Outline CAP further assessment of the mild sediment contamination was carried out 4. This indicated that negligible impacts on identified receptor would be expected and therefore no further action was recommended. It is noted that in the context of the drainage re-design outlined below it was proposed that the outfall from the Farmers Pond is diverted through a sealed pipe so that it no longer interacts with the storm water infrastructure of the site Progress The Farmer s Pond diversion works have been completed. 2.3 Stormwater Management Measures (S3 and S4) Stormwater management measures were proposed to address sources S3 (low level soil contamination across the subject area) and S4 (storage of treated timber adjacent to Ditch 2). It was proposed to install a management train of sustainable urban drainage systems (SuDS) elements. SuDS are proposed as they will use less energy and resources; will maximize the opportunities from storm water management; and will provide benefits for water quality (reduce contaminants), water quantity (reduce the amount of water discharged offsite), biodiversity and potentially an amenity. It was proposed that the SuDS treatment design will be in line with good practice, as set out in the CIRIA SuDS Manual The SuDS manual summarises good practice for SuDS treatment design as follows: Manage surface water runoff close to source. Treat surface water runoff on the surface. Treat surface water runoff to remove a range of contaminants. Minimise risk of sediment remobilisation. Minimise impacts from accidental spills. The outline objectives were as follows: Water quality reduce contaminants in stormwater at Licence Pt A to acceptable levels. Water quantity reduce peaks in discharge by containing events <5mm (similar to greenfield conditions) and attenuating, treating and controlling the discharge of larger events. Biodiversity provide localized improvement of biodiversity by creating more vegetated areas of grassland and/or trees. Amenity provide the potential for amenity use of vegetated areas for onsite workers. The proposed measures, their benefits and rationale for their implementation are presented below and illustrated in the design plans presented in Appendix C. The following elements form part of the proposed plan: Pervious Pavement 4 (2016) PDM Off-site Impacts Assessment dated 18/08/ CIRIA (2015) The SuDS Manual. Ref: CIRIA C753. London. Prepared for: 3

8 It was proposed to install pervious pavement (soil stabilisation) to cover all track access and raw timber storage bays in the subject area. The pervious pavement will reduce the risk of erosion of low level contaminated sediment reported across the subject area. The pervious pavement will intercept rainfall where it falls in the subject area and reduce the frequency and volume of runoff. It will also provide treatment benefits in terms of filtration, adsorption, biodegradation and sedimentation for any contaminants which pass through it. It is noted that to limit the generation of dust and sediment was proposed to construct two (2) asphalt road spurs to access the storage bays. Filter Drains It was proposed to install a system of filter drains in the subject area. Filter drains are shallow trenches filled with gravel that provide temporary subsurface storage, attenuation, conveyance and filtration of surface water. Filter drains also encourage adsorption and biodegradation processes. Swales It was proposed to replace existing Ditch 2 with a shallow swale and buffer zone between the swale and the treated timber storage area (S3). The buffer zone is discussed further below. The proposed swale is a shallow flat bottomed vegetated open channel which is designed to convey, treat and attenuate surface water runoff. Swales facilitate sedimentation, filtration through the root zone and soil matrix, evapotranspiration and infiltration. Additionally, where sediment is exposed to UV light photolysis and volatilisation can also breakdown PAHs. Vegetated Buffer Zone To mitigate against wind-blown contamination or incidental spills from the treated timber storage area (S4) it was proposed to infill the existing ditch (replaced by swale above) and to create a vegetated buffer zone between the treated timber storage area and the swale. The buffer zone will reduce the potential for contamination of runoff in the subject area; increase infiltration and evapotranspiration; provide treatment in terms of phytoremediation for any contaminants that fall on the area; and improve local biodiversity. It should also allow for the visible identification of any contaminants that fall on the surface. Wet Pond All water conveyed through the new swale and Ditch 3 will enter the proposed wet pond. The wet pond will provide for sedimentation, attenuation and treatment of runoff. The outflow will be controlled and water levels can increase following rainfall events. Vegetation in the pond will enhance treatment and biodiversity. It was proposed to line the pond due to the high perched water table anticipated beneath the subject area. Future proofing elements include the installation of ducting (power) and the provision of a pumping chamber to allow for water treatment prior to discharge should this be necessary (eg. following an accidental spill) Progress Construction of the stormwater management measures has been completed and the system is currently going through a commissioning phase. 3. Licence Pt E Catchment Table 2 below summarises the viable S-P-R linkages considered to be present within the Licence Pt A catchment. These were determined on the basis of the Conceptual Site Model (CSM) developed for the site. A location map illustrating the viable S-P-R linkages is provided in Appendix D. Table 2 Viable Source-Pathway-Receptor linkages. Key Sources Potential Pathway Potential Receptors Hot Spot of contaminated sediment in Drainage Ditch 4. (S1) Outdoor ingestion of soil and fugitive dust from contaminated shallow soil and outdoor dermal contact with soil. (P1) Workers at the site considering a continued commercial end use. (R1) Prepared for: 4

9 Key Sources Potential Pathway Potential Receptors Flow to surface water drainage network via gullies and separator. Emission at Licence Pt E via WWTP. (P2) Creosote Storage and Treatment Areas, Main Site Separator. (S2) Overland flow directly offsite bypassing surface water drains and surface water drainage network. (P3) Treated product storage areas. (S3). Exposed contaminated (low level) soil across the site (S4). Flow to surface water drainage network via gullies. Emission at Licence Pt E via WWTP. (P4) Overland flow directly offsite bypassing surface water drains and surface water drainage network. (P3) Overland flow or overflow (MH8) to drainage ditches leading to Ditch 1 during periods of high rainfall. Emission at Licence Pt E via WWTP. (P5) Overland flow to Drainage Ditches 1 and 4 during periods of high rainfall. Emission at Licence Pt E via WWTP. (P6) Overland flow to surface water drainage network via gullies. Emission at Licence Pt E via WWTP. (P7) Kill River, Killhill River and Painestown River. (R2) Hot Spot of contaminated sediment in Drainage Ditch 4 (S1) and contaminated sediment in the drainage network (S5). Overland flow directly offsite bypassing surface water drains and surface water drainage network. (P3) Flow through the surface water drainage network. Emission at Licence Pt E via WWTP. (P8) S5 Only - Overland flow or overflow (MH8) to drainage ditches leading to Ditch 1 during periods of high rainfall. Emission at Licence Pt E via WWTP. (P5) Kill River, Killhill River and Painestown River. (R2) The proposed outline strategy to address the S-P-R linkages identified above can be divided into three parts. 1. Source reduction measures, including maintenance and dredging works to remove contaminated sediment (S1 and S5); 2. Stormwater and Surface Water management and infrastructure improvement measures associated with treatment areas (S2 and P3) and areas dedicated to the storage of treated timber (S3 and P5) including landscaping and road/storage surface upgrade works to reduce erosion impacts from low level soil contamination (PAHs) across the subject area s exposed surfaces (S4 and P7); and Prepared for: 5

10 3. Upgrade of the WwTP to improve treatment and compliance at Licence Pt. E (P2 and P4 to P8). Drawings detailing the proposed remedial actions for the Licence Pt E catchment are provided in Appendix E. It is noted that the drawings are provided for illustration purposes only. It should be noted that unforeseen circumstances during construction might result in amendments to the plan presented herein. 3.1 Soil Contamination Hot-Spot (S1) Remedial Action Three options were considered to address the hot spot soil contamination reported in Drainage Ditch 4: Excavation and disposal of contaminated soil; Selective excavation and containment / encapsulation of residual contaminated soil; and Containment / encapsulation of contaminated soil. During optioneering, the highest score was obtained for the containment and selected excavation and disposal option (94), involving the removal of a nominal 36m 3 of soil and the installation of an impermeable hard standing and/or suitable lining design. The second highest score (90) was obtained for the excavation and disposal option. The works would involve the excavation and disposal to a licensed waste facility of a nominal 36m 3 of soil. Reinstatement would be completed using clean backfill available on site to the extent of infilling the full volume of the former drain. This was the recommended for the remedial works implemented in the context of upgrade works relating to the surface drainage infrastructure which include the full decommissioning of the drainage ditch Progress Works are currently being progressed on site as part of the site infrastructure upgrade works. At the time of writing, the remedial works have been completed but infilling of Drainage Ditch 4 is not expected to be completed until later in the project. The infrastructure upgrade works are expected to be completed by June Maintenance of the Exiting Drainage Pipework (S5) Remedial Action It was initially proposed to carry out cleaning and sediment removal from the existing drainage pipework to prevent mobilisation of potentially contaminated deposits that might have accumulated within 3. However, during design development and following further assessment the reuse of existing drainage infrastructure was considered unviable with few exceptions. Therefore most of the existing drainage will be decommissioned Progress Works are currently being progressed on site as part of the site infrastructure upgrade works. The infrastructure upgrade works are expected to be completed by June Low Level Soil Contamination (S4 and S7) Remedial Action To prevent or limit the migration of contaminants from exposed soils showing low levels of contamination, it is proposed to implement the following mitigation measures: Pervious pavements: it is proposed to install pervious pavement surfaces (soil stabilisation) in those areas impinged by site traffic and operations (such as the fabrication timber storage). The pervious pavement will reduce the risk of erosion of low level contaminated sediment reported across the subject area. The pervious pavement will intercept rainfall where it falls in the subject area and reduce the frequency and volume of runoff. It will also provide treatment benefits in terms of filtration, adsorption, biodegradation and sedimentation for any contaminants which pass through it. Vegetated areas: it is proposed to complete landscaping and greening works in those areas not impinged by operational activities. The vegetated areas will reduce the potential for contamination of runoff in the subject area; increase infiltration and evapotranspiration; provide treatment in terms of phytoremediation for Prepared for: 6

11 any contaminants that fall on the area; and improve local biodiversity. It should also allow for the visible identification of any contaminants that fall on the surface. Impermeable pavement: it is proposed to construct a number of roads and service areas (including refuelling and creosote delivery pads) that will be covered with impermeable surfaces. These will prevent run-off from coming in to contact with the soil. Run-off from these areas will be collected in to the drainage system Progress Works are currently being progressed on site as part of the site infrastructure upgrade works. The infrastructure upgrade works are expected to be completed by June Resurfacing of Critical Areas (P2 to P5) Remedial Action It is proposed to carry out resurfacing works at the creosote storage and timber treatment areas. While the consequent positive impacts would be mostly relating to possible groundwater infiltration, resurfacing of these areas (in conjunction with the drainage remedial works illustrated below) will limit the risk of uncontrolled, potentially contaminated discharges over ground. It is noted that the refurbishment plan for the Drag Out Area will include an upgrade to the sidings of the rails for Treatment Units 3 and 4. This will allow loading of a new charge of timber immediately after the previous charge is extracted from the vessel, which will have positive environmental effects by limiting the time that the vessel remains open. It will also limit the temperature loss in the vessel between charges providing energy efficiency advantages Progress Works are currently being progressed on site as part of the site infrastructure upgrade works. The infrastructure upgrade works are expected to be completed by June Upgrading of Site Drainage Infrastructure (P2 to P8) Remedial Action An extensive plan of works is proposed to upgrade the drainage infrastructure on the site. The works will reduce the risks of system overflow and consequent uncontrolled discharges (over ground, via Drainage Ditch 4 and via Drainage Ditch 1), as well as improving the control of flows and water quality reaching the WwTP. The proposed works will include: Upgrading of the site drainage infrastructure (interceptors, gullies, sumps, pipework etc.) to include: Separation of surface water and roof run-off collection systems; Zoning of the site drainage to control and limit accidental spill events. Upgrading of the current collector drains for the collection of flow of roof run-off and surface water from hard standing areas (concrete pads and surfaces, roads, etc.). Upgrading of the pumping and attenuation infrastructure controlling water flows from the collector drain to the WwTP. The objective of the proposed storm water attenuation and balancing plan is to provide attenuation and balancing storage for pass forward to either the existing WwTP for treatment or if shown to be sufficiently clean to discharge directly at a new storm water emissions Monitoring Point. Provisions for the potential separate discharge (untreated) of roof run-off are also included in the proposed design. It is noted that the overall capacity of the system will be substantially increased. The proposed new Pumping Station and Balance Tank will be instrumented and will provide online and manual controls to allow shut off and containment in the event of an incident on site (such as a fire or spillage) as well as automated controls in case of mechanical failures in the system Progress Works are currently being progressed on site as part of the site infrastructure upgrade works. The infrastructure upgrade works are expected to be completed by June Prepared for: 7

12 3.6 Upgrading of the Wastewater Treatment Plant (P2 to P8) Remedial Action It was initially proposed to refurbish and upgrade the existing Wastewater Treatment Plant (WwTP) 3. However, during detailed design development and inconsideration of the sustained compliance at Licence Pt E (since March 2016) it is now proposed to review the optioneering carried out for the WwTP. It is noted that the improved compliance is deemed to be associated with improved environmental and operational practices being implemented at the site Progress The review of the optioneering will be carried out following a pilot testing period to be completed after the construction works are complete. The pilot testing will aim to assess the performance of the existing infrastructure under the new loading conditions and influent characteristics. Future proofing is however included in the proposed design for the new Balance Tank to allow for the connection of additional treatment units for temporary and/or long term augmentation of the treatment train. It is noted that should the current system perform satisfactorily it would provide a low carbon and sustainable treatment solution for the site. Prepared for: 8

13 Appendix A Site Location Map Prepared for: 9

14 Appendix B Licence Pt A Conceptual Site Model (CSM) Prepared for: 10

15 Appendix C Licence Pt A Corrective Action Drawings Prepared for: 11

16 Appendix D Licence Pt E Conceptual Site Model (CSM) Prepared for: 12

17 Appendix E Licence Pt E Corrective Action Drawings NOTE: Drawings are provided for illustration purposes only. Unforeseen circumstances during construction might result in amendments to the plan presented here. Prepared for: 13

18 aecom.com Prepared for: 14