Glengad Landfall Intertidal Survey Report (Summer 2008)
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GLENGAD LANDFALL INTERTIDAL SURVEY REPORT (SUMMER 2008) For inspection purposes only. Consent of copyright owner required for any other use. SHELL E&P IRELAND LTD P40036 January 2009 (Rev 01) EPA Export 20-02-2014:23:29:24 RSK Environment Ltd Glengad Landfall Intertidal Survey Report RSK General Notes Project No: P40036 Title: Glengad Landfall Survey Report Client: Shell E&P Ireland Ltd. Issue Date: January 2009 Issuing Office: Helsby Authorised by: David Watson Project Manager Date: 23rd January 2009 Authorised by: Alec Moore Project QA Rep Date: 23rd January 2009 For inspection purposes only. Consent of copyright owner required for any other use. AM AB January E 01 Final 2009 AM DW January E 00 Draft 2009 AUTHOR CHECKED DATE ISSUED POST REV PURPOSE OF ISSUE ISSUED / ELECTRONIC RSK/H/P/P40036/Landfall survey June 2008_rev01 i January 2009 EPA Export 20-02-2014:23:29:24 RSK Environment Ltd Glengad Landfall Intertidal Survey Report CONTENTS 1. Introduction...............................................................................1 1.1 Background.................................................................................................1 1.2 2005 survey..................................................................................................1 1.3 2008 survey..................................................................................................1 2. Methods.....................................................................................2 2.1 General........................................................................................................2 2.2 Surface sediment physico-chemistry.......................................................2 2.3 Benthic infauna...........................................................................................2 3. Results ......................................................................................5 3.1 Surface sediment physico-chemistry.......................................................5 3.1.1 Particle size analysis................................................................................................................5 3.1.2 Total Organic Carbon ..............................................................................................................5 3.1.3 Comparison with 2005 data .....................................................................................................5 3.2 Benthic infauna...........................................................................................7 3.2.1 General ....................................................................................................................................7 3.2.2 Diversity ..................................................................................................................................7 3.2.3 Taxonomic composition ..........................................................................................................8 3.2.4 Abundance...............................................................................................................................8 3.2.5 Comparison with 2005 data .....................................................................................................8 3.2.6 June 2008 Station descriptions ................................................................................................9 4. References ..............................................................................13 For inspection purposes only. TABLES Consent of copyright owner required for any other use. Table 2.1: Co-ordinates of sampling stations referred to in the present report...............................2 Table 3.1: Particle size and organic carbon data for Glengad landfall sediments. ..........................6 Table 3.2: Summary diversity and abundance data for June 2008 survey, based on fauna retained on a 0.5mm sieve ......................................................................................................................7 Table 3.3: Benthic infauna species list for the 2008 and 2005 survey.............................................7 Table 3.4: Macrofauna retained on 1mm mesh sieve: comparison of data between 2005 and 2008 ...................................................................................................................................................9 FIGURES Figure 2.1: Location of sampling stations at Glengad landfall..........................................................3 Figure 3.1: Wind-blown sediment and strandline material at LCS1, upper shore............................9 Figure 3.2: Wet rippled sand with drift algae at LCS2 ....................................................................10 Figure 3.3: Rippled high-energy sand at ZX1; upper shore ...........................................................11 Figure 3.4: Damp rippled sand and core sampler at station ZX2, mid shore station .....................11 Figure 3.5: Flat freely draining sand amongst rock outcrop on upper shore at landfall transect, upper shore. ............................................................................................................................12 Figure 3.6: Uniform medium sand on mid shore, landfall transect.................................................12 RSK/H/P/P40036/Landfall survey June 2008_rev01 ii January 2009 EPA Export 20-02-2014:23:29:24 RSK Environment Ltd Glengad Landfall Intertidal Survey Report APPENDICES APPENDIX 1: RAW SEDIMENT DATA APPENDIX 2: RAW BENTHIC INVERTEBRATE DATA For inspection purposes only. Consent of copyright owner required for any other use. RSK/H/P/P40036/Landfall survey June 2008_rev01 iii January 2009 EPA Export 20-02-2014:23:29:24 RSK Environment Ltd Glengad Landfall Intertidal Survey Report 1. INTRODUCTION 1.1 Background Shell E&P Ireland Ltd. (Shell) have been granted consent to install a gas pipeline from the offshore Corrib field to a processing terminal at Bellanaboy Bridge in County Mayo (Republic of Ireland). This route requires a pipeline landfall at Glengad, on the coast of Broadhaven Bay. 1.2 2005 survey As part of the ecological monitoring programme for the development, pre-construction surveys of the intertidal environment have been commissioned by Shell. The first of these pre-construction surveys was undertaken by Ecological Consultancy Services Ltd (EcoServe) in June 2005 (EcoServe, 2005), in anticipation of works occurring later that year. However, works were postponed until summer 2008 and because of this delay it was agreed that an additional pre-construction survey would be carried out to provide updated baseline data. 1.3 2008 survey RSK Environment Ltd (RSK) were contracted by Shell to perform this pre-construction survey of the landfall, which was undertaken on the 11th and 12th June 2008. Several aspects of the 2005 survey were retained in order to provide comparable data. These included the position of the two transects (LS and LCS, each with three stations at upper, mid and lower shore) and the use of four 10.5cm diameter core replicates for macrofaunal sampling. However, some additional aspects were included in order to provide further information on the environment: an extra transect (ZX) was added between the two transects sampled in 2005. While 2005 samples were processed for macrofauna by sieving over a 1mm mesh only, samples in the 2008 survey were also sieved over a 0.5mm mesh in order to provide both comparable data to the 2005 survey and to provide further fine-scale detailed information. For inspection purposes only. Consent of copyright owner required for any other use. The pre-construction survey was intended to be the baseline against which further (post- construction) surveys were to be measured. These surveys were due to take place 1 month and 6 months post-construction and finally one year after the pre-construction survey. The one month and 6 month post-construction surveys were to have a reduced scope (only grain size and total organic carbon to be analysed). RSK/H/P/P40036/ Landfall survey June 2008_rev01 1 January 2009 EPA Export 20-02-2014:23:29:24 RSK Environment Ltd Glengad Landfall Intertidal Survey Report 2. METHODS 2.1 General The survey was conducted by two RSK Environment Ltd marine ecologists on the 11th and 12th of June 2008. Survey work was timed to coincide with low-water for maximum exposure of the intertidal; however, LS3 was covered at the time of survey and as such the nearest practical area was sampled. Stations were located using a hand-held GPS unit (Garmin GPS60, accurate to ~5m or less). Positions of the stations sampled are presented in Table 2.1 and on Figure 2.1. Table 2.1: Co-ordinates of sampling stations referred to in the present report. Station Latitude (North) Longitude (West) LS1 54.2834 9.821 LS2 54.2836 9.8219 LS3 54.2836 9.8223 LCS1 54.2862 9.8124 LCS2 54.2885 9.8176 LCS3 54.289 9.822 ZX1 54.2849 9.8161 ZX2 54.2856 9.8185 ZX3 54.286 9.8233 2.2 Surface sediment physico-chemistry For particle size analysis, a sample of approximately 500ml volume was taken using a trowel from the surface 5cm of exposed intertidal sediment. All PSA samples were stored in double-labelled plastic bags. Samples were then despatched to, and analysed by, the Environment Agency’s National Laboratory Service, U.K. Raw sediment data are presented in Appendix 1. For inspection purposes only. Consent of copyright owner required for any other use. Sediments are classified according to Folk (1954) based on their relative contents of gravel (>2mm), sand (>63µm to 2mm) and mud (<63µm);