Habitat reinstatement, restoration and creation on the Corrib Gas Onshore Pipeline in Co Mayo, Ireland - challenges and solutions

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1 Habitat reinstatement, restoration and creation on the Corrib Gas Onshore Pipeline in Co Mayo, Ireland - challenges and solutions Jenny Neff CEcol CEnv FCIEEM EACS - Ecological Advisory and Consultancy Services

2 Location and project elements A t l a n t i c O c e a n 10 W Corrib Field 200 Broadhaven Bay Erris Head Atlantic Ocean Northern Ireland Eagle Island Ireland EACS - Ecological Advisory and Consultancy Services 2

3 Onshore pipeline Total Length: 9.2km from landfall at Glengad to the gas terminal at Bellanaboy 4.9 km tunnel (4.5m diameter) made by a manned TBM under Sruwaddacon Bay - part of Blacksod Bay/Broadhaven SPA and Glenamoy Bog Complex SAC (mitigation by design). Habitat reinstatement except for the Landfall Valve Installation (LVI) at Glengad, in accordance with requirements and commitments made - as enshrined in statutory consents; approved EMP and R&A Plan; Project BAP and LMP etc. Opportunities for restoration and biodiversity enhancement NNL/NPI Pilot Study 2011 / predicted outcome EACS - Ecological Advisory and Consultancy Services 3

4 Landfall Valve Facility Glengad Pipeline Route Aughoose Leenamore Gas Terminal EACS - Ecological Advisory and Consultancy Services 4

5 Project commitment to reinstate to the benefit of wildlife and habitat the aims Landfall reinstatement of semi-improved grassland Allow the site to re-vegetate naturally. Leenamore inlet (Annex I Habitats) Salt marsh protection: excavate and store in the intertidal zone but with protection, avoid prolonged storage of salt marsh vegetation before reinstatement. Intertidal: lift epiphyte - covered cobbles and 300mm benthic layer store separately Atlantic Blanket bog habitats Using stone road concept peat stone matrix at the base and regulation layer and peat turves/peat vegetation on top Retain hydrological function of the peatland (avoid vertical/horizontal drainage paths) Underlying requirements in order to achieve successful reinstatement. Forested wayleave Plant native deciduous woodland along the sides of the wayleave and create wetland habitat. EACS - Ecological Advisory and Consultancy Services 5

6 Timelines for reinstatement LOCATION ROUTE SECTION INDICATIVE TIMELINE FOR REINSTATEMENT Glengad Installation of the surface water outfall pipe at the LVI From the LVI to approximately 50m west of the Tunnel Reception shaft SC2 compound and eastern section Cliff reinstatement : completed Q Remedial repairs completed Q Aughoose Compound (SC3) Leenamore Inlet crossing Completed Q Fields on either side of the Leenamore The 190m section, recovering blanket bog Completed Q Completed Q m to Terminal Forested Area 190m to RDX1 completed Q RDX1 to DL6 completed Q DL6 to Terminal Q EACS - Ecological Advisory and Consultancy Services 6

7 EACS - Ecological Advisory and Consultancy Services 7

8 Leenamore inlet habitats Annex I Atlantic salt meadows (Glauco- Puccinellietalia maritimae) (1330) Upper Salt marsh dominated by the Juncus maritimus; Lower Salt Marsh with low grassy sward dominated by Puccinellia maritima, with Glaux and Armeria. Annex I estuarine habitat Mudflats and sand flats not covered by sea water at low tide (1140) Epiphytic flora and epifauna attached to cobbles on the surface. Brown fucoid seaweeds being dominant. Benthic species occur in the shallow top layer (300mm) of sediments. EACS - Ecological Advisory and Consultancy Services 8

9 Leenamore - challenges Successful reinstatement dependent upon: The necessary habitat mitigation measures being correctly implemented during construction, including: Management of temporary translocation and- of salt marsh, cobbles and the top benthic layer (300mm) of intertidal sediments. Storage of the habitats at the correct height in the intertidal zone for as short a period as possible Challenges: Client and contractor buy-in: consultation, education and guidance Construction - imposed constraints including duration and extent How to maintain the correct salt marsh zones Salt marsh substrate EACS - Ecological Advisory and Consultancy Services 9

10 Solutions Contractor buy-in : explanation, education (preconstruction workshops and tool box talks), ecological support and guidance throughout Duration ensured design included suitable storage of habitat elements Salt marsh, cobbles with epiphytes, and benthic layer all stored separately in the intertidal zone during construction Salt marsh substrate: Vital that salt marsh was reinstated at the correct elevation to ensure the correct vegetation type was maintained Re-worked peat would not have supported the salt marsh turves and Ecologists, geotechnical engineers and contractor agreed to use a peat stone mix to support the reinstated salt marsh and a semi-permeable Geotextile to control sediment seepage post-construction - held in place by cobbles. In time the cobbles will provide additional niche habitats for crustaceans etc. and one year on the cobbles are being colonised by epiphytes. EACS - Ecological Advisory and Consultancy Services 10

11 Salt marsh - GIS referencing Original position Temporary storage area EACS - Ecological Advisory and Consultancy Services 11

12 Salt marsh translocation and storage Dammed inlet floods after Exceptional high spring tide Depth of peat = up to 2m under upper salt marsh Geo-referencing and labelling turves prior to lifting Salt marsh storage area after 10 days note colour of vegetation EACS - Ecological Advisory and Consultancy Services 12

13 Leenamore inlet - pipelay EACS - Ecological Advisory and Consultancy Services 13

14 Leenamore inlet: reinstatement Spreading the base peat/ stone layer EACS - Ecological Advisory and Consultancy Services 14

15 Salt marsh reinstatement EACS - Ecological Advisory and Consultancy Services 15

16 Leenamore inlet Before construction 9 months post reinstatement EACS - Ecological Advisory and Consultancy Services 16

17 Leenamore - landscape overview Before construction One year post reinstatement EACS - Ecological Advisory and Consultancy Services 17

18 The big reinstatement challenge for 2015 The aim of reinstatement of the Aughoose compound is to establish a functioning peat-based habitat with created wetlands interspersed in an area which, prior to construction, comprised modified Atlantic blanket bog habitats. EACS - Ecological Advisory and Consultancy Services 18

19 EACS - Ecological Advisory and Consultancy Services 19

20 Aughoose stored surface vegetation Peat storage area A May 2014: Eriophorum angustifolium and E. vaginatum EACS - Ecological Advisory and Consultancy Services 20

21 Aughoose compound - reinstatement plan EACS - Ecological Advisory and Consultancy Services 21

22 Main challenge: Aughoose reinstatement Stored surface vegetation equates to approximately one-third of the area to be reinstated Planned solutions: Areas of bare peat: Native ericaceous seed (collected autumn 2014) Plant plugs E. angustifolium and Carex panicea (collected locally ) Sphagnum moss beads BeadaMoss Wetland habitat creation Populate re-created drains with Sphagnum taken from an old cutover at Aughoose in 2011 prior to construction and temporarily stored locally and grown on in drains at a commercial cut away. EACS - Ecological Advisory and Consultancy Services 22

23 Collection of Sphagnum moss at Aughoose in 2011 for BeadaMoss production in UK for use in reinstatement 2015/2016 BeadaMoss trial on 190m EACS - Ecological Advisory and Consultancy Services 23

24 Ongoing challenges invasive species EACS - Ecological Advisory and Consultancy Services 24

25 TO SUMMARISE Specialists worked closely across disciplines with client management, design and construction engineers; and assisted in developing methodologies to address ecological requirements in order to achieve mitigation by design. Solving problems together on the ground - as they arise. Exploring and exploiting opportunities for biodiversity enhancement and habitat creation using native species and novel methods. Opportunity to restore previously overgrazed areas of blanket bog unaffected by construction (now in the ownership of the project) to Annex I quality. Development of project Biodiversity Action Plan (Client buy in essential and global group support helps too!). BAP commitment for Land Management Plan which enshrines best practice stewardship of habitats and species; and monitoring into the future (Landfall to, and including, the terminal site of 160ha). Predicted to have Net Positive Impact /Gain (NPI/NPG) by 2020 (The Biodiversity Consultancy, report 2011) currently on target! EACS - Ecological Advisory and Consultancy Services 25

26 Further reading and information Links to Corrib: BAP: The Corrib project - environment: The Corrib project - general: EACS - Ecological Advisory and Consultancy Services 26

27 EACS - Ecological Advisory and Consultancy Services 27

28 ADDITIONAL SLIDES EACS - Ecological Advisory and Consultancy Services 28

29 Glengad landfall The landfall area at Glengad is in the buffer zone of Glenamoy Bog Complex SAC on the southern edge of dune complex. Construction areas comprise semi- improved grassland Aim: Reinstate semi-improved grassland by allowing the site to re-vegetate naturally. Challenges: No imported seed permitted relying on natural regeneration of vegetation from seed and by vegetative means Repeated top soil stripping (2002, 2005, 2008, 2009, 2012) Duration of soil stock piling (currently since 2012 in parts) Steepness of Landfall Valve Installation (LVI) side slopes Outcomes to date: Despite this the reinstatements to date have been successful see next slide and 2009 where some of the soil had been stockpiled since LVI side slopes 2014 with good vegetation cover within weeks of top soil spreading Precaution (belt and braces): this year have collected seed from the adjacent semi-improved and fixed dune grassland to have in hand in case needed. EACS - Ecological Advisory and Consultancy Services 29

30 Glengad landfall and tunnel reception Offshore works 2009 Reinstated landfall site September 2009 Reinstated landfall site in June /2014 EACS - Ecological Advisory and Consultancy Services 30

31 Glengad LVI side slopes Top soil spreading on LVI side slopes (19 June 2014) Vegetation regeneration on side slopes (18 September 2014) EACS - Ecological Advisory and Consultancy Services 31

32 The 190m blanket bog recovering from previous overgrazing EACS - Ecological Advisory and Consultancy Services 32

33 190m Atlantic Blanket bog habitat recovering to Annex I status (not yet Active*) Aims and methods Using stone road concept peat stone matrix at the base and regulation layer and peat turves/peat vegetation on top Retain hydrological function of the peatland (avoid vertical/horizontal drainage paths) Underlying requirements in order to achieve successful reinstatement. EACS - Ecological Advisory and Consultancy Services 33

34 190m construction and challenges Nesting Skylark caused 3 week delay in lifting blanket bog turves in the exclusion zone and construction programme to be prolonged. Bog mats placed ready to receive blanket bog turves Blanket bog turves stored on bog mats with central bog mat road for access by bowser for watering in dry weather EACS - Ecological Advisory and Consultancy Services 34

35 Stone Road Construction / Mitigation hydrology and ecology Peat plugs Regulation layer Peat turves placed on top EACS - Ecological Advisory and Consultancy Services 35

36 The 190m during reinstatement EACS - Ecological Advisory and Consultancy Services 36

37 190m post reinstatement Reinstated turves Overview of 190m (2014) EACS - Ecological Advisory and Consultancy Services 37

38 Forested wayleave : construction, habitat creation and biodiversity enhancement (north of RDX1) Planted deciduous native species Wetland number 3 EACS - Ecological Advisory and Consultancy Services 38

39 Forested wayleave (south of RDX1) Wetland number 6 EACS - Ecological Advisory and Consultancy Services 39