Non Technical Summary

Transcription

1 ENVIRONMENTAL STATEMENT Llanelli Sand Dredging Ltd Licence Variation Application for Aggregate Production Licence Area 476 Nobel Banks: Non Technical Summary October 2009 Environmental Resources Management Norloch House, 36 King's Stables Road, Edinburgh EH1 2EU Telephone Facsimile

2 ENVIRONMENTAL STATEMENT Llanelli Sand Dredging Ltd Licence Variation Application for Aggregate Production Licence Area 476 Nobel Banks: Non Technical Summary 22 nd October 2009 Reference For and on behalf of Environmental Resources Management Approved by: Mark Irvine Signed: Position: Technical Director Date: 22 nd October 2009 This report has been prepared by Environmental Resources Management the trading name of Environmental Resources Management Limited, with all reasonable skill, care and diligence within the terms of the Contract with the client, incorporating our General Terms and Conditions of Business and taking account of the resources devoted to it by agreement with the client. We disclaim any responsibility to the client and others in respect of any matters outside the scope of the above. Environmental Resources Management Limited Incorporated in the United Kingdom with registration number Registered Office: 2 nd Floor, Exchequer Crt, 33 St Mary Axe, London, EC3A 8AA

3 CONTENTS 1 INTRODUCTION I 1.1 AGGREGATE PRODUCTION LICENCE APPLICATION I 1.2 THE CONSENT PROCEDURE I 1.3 AVAILABILITY OF THE ES II 2 THE PROPOSALS II 2.1 THE PRODUCTION LICENCE APPLICATION AREA II 2.2 EXTRACTION METHODS III 2.3 EXTRACTION PROGRAMME III 2.4 NEED FOR THE PROPOSALS III 2.5 AGREED KEY MITIGATION MEASURES IV 3 IMPACTS OF THE PROPOSALS VI 3.1 PHYSICAL PROCESSES VI 3.2 WATER QUALITY VII 3.3 THE NATURAL ENVIRONMENT VII 3.4 FISHING VIII 3.5 DREDGING AND DUMPING ACTIVITIES IX 3.6 SHIPPING AND NAVIGATION IX 3.7 INDUSTRIAL AND SUBMARINE MANMADE INSTALLATIONS IX 3.8 MARITIME ARCHAEOLOGY AND CULTURAL HERITAGE X 3.9 MILITARY INTERESTS X 3.10 LEISURE, RECREATION AND AMENITY X

4 LICENCE VARIATION APPLICATION FOR AGGREGATE PRODUCTION LICENCE AREA 476, NOBEL BANKS ENVIRONMENTAL STATEMENT NON TECHNICAL SUMMARY 1 INTRODUCTION 1.1 AGGREGATE PRODUCTION LICENCE APPLICATION In 2006, Llanelli Sand Dredging Limited (LSDL) received a 10 year Aggregate Production licence from the Crown Estate for Licence Area 476 (Nobel Banks) in the Bristol Channel. The licence conditions limited aggregate extraction to a maximum of 300,000 tonnes per annum, not to exceed a total maximum of 3 million tonnes over the 10 year licence period. LSDL commenced dredging Nobel Banks in 2006 and is now applying to the Welsh Assembly Government for an variation to that licence for the remaining 7 years of its validity to increase the maximum annual extraction to 500,000 tonnes, whilst retaining the existing total maximum over the 10 year licence term of 3 million tonnes. This would allow LSDL to periodically respond to market demand for additional aggregate. The licence area covers approximately 93km 2, lying approximately 10 km west of Worms Head on the Gower Peninsula in South Wales, as shown in Figure 1. LSDL is aware of the continued public concern regarding further dredging on the Helwick Bank (Area 373) and this application is linked to the handing back of the existing Helwick Bank Aggregates Production Licence granted in 2005 but which has not yet been activated. The Helwick Bank licence allows for up to 150,000 tonnes per annum to be dredged over seven years. If the application to vary the Nobel Banks licence conditions to allow the extraction of up to 500,000 tonnes per annum is accepted in full then LSDL would hand back the licence to dredge the Helwick Bank. This Non Technical Summary (NTS) is part of an Environmental Statement (ES) that has been prepared by Environmental Resources Management (ERM). The ES reports on the results of an assessment of the environmental impacts of the proposals, updating the original 2002 ES with new information where relevant. The NTS provides an overview of the proposals, and their potential effects upon the environment and the mitigation measures that will be taken to reduce adverse impacts. 1.2 THE CONSENT PROCEDURE This ES has been prepared by Environmental Resources Management (ERM) on behalf of LSDL and presents the findings of an environmental impact assessment (EIA) of the proposals. Its purpose is to provide information to be I

5 considered by the Assembly in making its decision on whether to issue a licence. This information includes: a description of the proposed amendment to the licence and the environment in which it is located, identifying any environmental sensitivities in the area; identification, description and evaluation of the impacts predicted to arise from the amended operations; and a description of the measures which are being taken and would continue to be taken to mitigate those impacts. 1.3 AVAILABILITY OF THE ES Copies of the ES and associated reports in PDF format may be downloaded from the LSDL website: Copies on CD are also available at a cost of 5 plus VAT from ERM (Tel: ). 2 THE PROPOSALS 2.1 THE PRODUCTION LICENCE APPLICATION AREA Area 476 is located to the south west of the Gower Peninsula offshore of Carmarthen Bay. The production licence application site covers an area of 93 km 2. The area has been named the Nobel Banks (North Outer Bristol Channel). The seabed in the Nobel Banks comprises numerous, approximately north to south orientated sand-waves, which merge in the north to become the southern margin of the relatively flat sandy plane of Carmarthen Bay. The target resources typically comprise medium grained sands. The commercially marketable sand resources of the Nobel Banks are located primarily on the sand-waves, and on parts of the coastal shelf to the north, towards Carmarthen Bay. The troughs between the sand-waves constitute a substantial proportion of the application area, the deeper parts of which contain unsuitable materials and are beyond the operating capability of the dredging plant likely to be available. For the foreseeable future, dredging would be limited to a maximum depth of approximately 32 m below Chart Datum (CD). The licence area has an exclusion zone 500 m either side of a telecommunications cable which runs through the licence application area. The licence area also excludes the adjacent Carmarthen Bay and Estuaries Special Area of Conservation (SAC), which lies to the north-east. These exclusions make an effective licence area of approximately 76 km 2. II

6 The resource is suitable for a wide range of end uses including the manufacture of concrete, general building and construction, beach nourishment, coastal defences and as fill for reclamation projects. 2.2 EXTRACTION METHODS Aggregate extraction would be carried out using a trailer-suction-hopperdredger. This type of dredger trails a suction pipe along the seabed while moving forward at speeds of 1 to 3 knots. The draghead creates shallow furrows 1-2m in width on the seabed. In sandy sediments the draghead removes approximately 0.2 to 0.3m of material each time it passes over the seabed. The sediment would be pumped directly from the seabed into a hopper on the dredger where it would be stored before being transported to shore. For construction aggregate, the material would be stockpiled onshore before sale. The high quality of the resource is such that no onshore treatment, washing or grading before sale would be required. 2.3 EXTRACTION PROGRAMME Recovery of 500,000 tonnes each year would typically equate to a total of approximately 670 hours of dredging (less than 8% of the year) within areas defined by the proposed licence. Using LSDL s dredger the Sospan Dau, the dredging would be confined to approximately two 2-hour dredging periods each day that dredging takes place. If a larger dredger was to be used, the dredging time on the application area would be less. Three active dredging zones would be operated at any one time, covering a total of no more than 6 km 2, to provide the required range of material sizes. 2.4 NEED FOR THE PROPOSALS Marine aggregates are expected to remain an important resource within the United Kingdom, and are likely to continue to provide a significant proportion of the aggregates used in South Wales. There is a lack of existing sustainable alternative sources of fine aggregates to supply the South Wales market and there would be substantial difficulties in developing new landbased fine aggregate resources. The Nobel Banks have been identified in an independent report commissioned by the Assembly as strategically important to the South Wales aggregates market. The Nobel Banks fall mainly within the Outer Bristol Channel Area 10 as identified in the Assembly s South Wales Marine Aggregate Dredging Policy Consultation Document. This is a Policy 1 area, favoured for marine aggregate exploitation, providing there are no overriding environmental constraints. III

7 2.5 AGREED KEY MITIGATION MEASURES A number of agreed mitigation measures have been built into the dredging programme as part of the existing licence. LSDL would continue to implement these mitigation measures to reduce the impact of the proposals. LSDL will continue to monitor the seabed of the area surrounding extraction zones to enable identification of any changes in seabed morphology. The EIA takes these measures into account. Dredging Area and Strategy Exclusion of dredging within 500 m either side of the SOLAS cable route. Exclusion of the area of the Carmarthen Bay and Estuaries SAC and buffer area where dredging is permitted only on the ebb tide. The maximum depth of dredging operations will be restricted to 32 m below CD the maximum volume of material removed will be 500,000 tonnes per year, up to a total maximum of 3 million tonnes over the licence term. Exclusion of Other Users and Notifications Restriction of the active dredging area to 6 km 2 at any one time, comprising designated dredging zones. Access by other vessels to the zone being dredged is restricted during the periods of dredging activity. At all other times, there is no restriction to activities throughout the whole of the licence area. 6 months notice (to the Assembly, DEFRA and Crown Estate) to change the active dredging areas. Dredging vessels to be used are fitted with a DGPS that allows accurate positioning of the vessel within 1m. This allows the resource to be targeted accurately and avoids interference with other seabed users and structures. Dredging vessels are also fitted with an EMS to ensure that dredging operations were kept within the agreed extraction zones. The EMS, which is monitored by the Crown Estate and Regulator, records the vessel s position every 30 seconds during dredging operations and whilst in transit to and from the licence area. Navigation notices will continue to be issued over the radio. SWWFC will continue to provide fishing liaison and will be regularly kept informed by LSDL of active dredge zones. IV

8 Avoidance of Vessel Collisions International Safety Management (ISM) procedures for dealing with potential collision and pollution scenarios that could result are already in place within LSDL and include Emergency Response Plans (ERPs). A record of accidents and near misses will be maintained by LSDL to allow procedures to be reviewed. Dredging vessels are equipped with the appropriate navigation and warning equipment (lights, fog warnings, radar and VHF radio) and comply with the requirements of the International Regulations for Preventing Collisions at Sea (1972). Automatic Identification System (AIS) transponders will be installed as per statutory requirements on any dredger operating in the area. This system identifies particular vessels operating in the area to other vessels in the area which have this system installed. This increases the likelihood of other vessels passing through the area knowing that a vessel is dredging and allow them to plan their route accordingly. Archaeological Finds and Wreck sites there would be full compliance with the regulations set out under the Protection of Wrecks Act 1973, and the Merchant Shipping Act 1894 regarding reporting and ownership of wreck and notification to the Receiver of Wreck; any archaeological finds would be reported to the regional archaeologists trust (GGAT) and to the RCAHMW for incorporation into database records; advice would be sought from GGAT and RCAHWM regarding any further surveys required in the event of finds; the Joint Nautical Archaeological Policy Committee (JNAPC) Code of Practice for Seabed Developers would be observed; and a 100 m exclusion zone would be observed by the dredging vessel around any identified sites of archaeological interest. Monitoring A programme of environmental monitoring is being carried out by LSDL. The scope of the monitoring has been agreed with WAG and DEFRA and is specified in the licence conditions. It includes bathymetric surveys, to ensure that extraction levels are within those specified in the licence conditions and to safeguard the integrity of other seabed structures such as cables, as well as benthic surveys and seabed composition surveys. V

9 3 IMPACTS OF THE PROPOSALS The effects of the proposals on the environment, including the physical, natural and human environment (ie people using the area for various activities) are summarised below. 3.1 PHYSICAL PROCESSES Nobel Banks is one of a number of sand-wave fields extending from south of the Gower Peninsula almost as far as Lundy Island. The seabed of the Nobel Banks area has a series of 2 to 5 km long north-south orientated sandy ridges, 500 to 2000 m apart and ranging from 8 to 16 m in height and 25 to 44 m in depth below CD. The bulk of the sand within each wave is relatively immobile but there is a layer of mobile sand at the surface. This may be the result of the sand-waves either being relict features formed thousands of years ago, or being active but changing so slowly that movement cannot be detected over a time scale of decades. In the Bristol Channel in general, tidal currents move seabed sediment towards the west, whereas storm waves move seabed sediment in an easterly direction. There is no proven link between the sediments within the proposed Nobel Banks dredging area and areas closer inshore, eg Helwick Bank and the Gower Peninsula. The Nobel Banks may act as a buffer to changes in sediment transport between adjacent areas. The assessment of the potential impacts that might result from the proposed dredging operations on the physical environment of the Nobel Banks has concluded the following. The Nobel Banks are not acting as a barrier to storm waves under current conditions because they are too deep. Further deepening would not affect the height of waves that approach the coast, and no impacts on the coast are predicted from the changes in height of the sand-waves. Tidal currents would be slightly altered in the immediate area of the depression created by the dredging due to the changes in bathymetry, but modelling predicts there would be no appreciable difference in currents outside the dredging area. There would be no rapid or significant change in the morphology of the Nobel Banks or surrounding area as a result of the proposed amended rate of extraction from above the 32 m depth contour. Although there may be temporary removal of mega-ripples and the crests of sand-waves, the net transport of at least 1,300 tonnes of sediment over the area in each spring tide means that the existing variations in water depth, seabed gradient and sediment distribution would remain as they are today for the remainder of the extraction licence. VI

10 It is predicted that the changes in wave propagation as a result of the assumed extraction would be roughly 25 times smaller than reported in the original 2002 ES due to the more modest quantities of sand dredging now licensed and proposed, and will be significantly below the level of change regarded as significant by CEFAS, resulting in negligible potential for changes in coastal erosion. No effects on the general sediment transport regime in the Bristol Channel, and particularly on coastal sediment transport, are anticipated, due to the comparatively small amount of sand that would be removed. Specifically, no beach draw-down is predicted as a result of the proposed operations and no cumulative impacts from the proposals and ongoing dredging at Helwick Bank are predicted. Monitoring of the Nobel Banks would identify offshore morphological changes at an early stage and appropriate measures would be taken as necessary to prevent any adverse effects. Cumulative impacts to coastal morphology as a result of dredging activities in Areas 476 and Application Area 486 located immediately to the south of Area 476 were assessed during the Coastal Impact Study for Area 486. The study concluded that there would be no cumulative impacts on coastal morphology for the total maximum extraction applied for at both sites. No impacts from the proposed licence variation are therefore predicted. 3.2 WATER QUALITY Sand would be temporarily released into the water during dredging activities, resulting in a temporary and slight increase in localised suspended sediments and turbidity. The coarser material would settle out rapidly affecting only a small area around the dredger path, but fine sediments (less than mm) would take longer to settle and would form a plume extending along the direction of the prevailing tidal current. There is only a small proportion of fine sediment in the seabed material of the Nobel Banks and the dredging strategy has been designed to target areas of clean sand (ie areas with high sand and low mud, fines or coarse material content). Also, there are no known areas of contaminated sediment within the Nobel Banks area. Suspended solids from dredging would be likely to add to background levels for a short period of time and distance from the dredge site prior to decreasing as a result of the sediment settling out of suspension and mixing with un-impacted waters. Impacts on water quality would therefore be limited in degree, extent and duration. 3.3 THE NATURAL ENVIRONMENT The results of the CIS for the original licence application indicated that there would be no significant impacts to coastal areas and therefore there would be no impacts on coastal sites designated for their geological or nature conservation interest. The review of the proposed licence variation agrees VII

11 with the findings of the original report that there will not be any impacts to coastal sites. The proposed licence area is considered not to be an important feeding area for birds and no impacts on birds or on sites designated for their bird interests are expected. Disturbance to seabirds, sea mammals and fish due to the presence of the dredging vessel would be of short duration and magnitude taking into account the scale and duration of the dredging operations and the existing levels of shipping traffic in the area. The dredging operations would have a direct impact on seabed habitats and the associated animal communities. The seabed habitats and the types and numbers of animals identified during a baseline survey carried out in 2006 and monitoring survey carried out in 2008 showed that the dredging areas are generally similar to the surrounding area and other sand banks in the coastal waters of the British Isles. The seabed communities and species are adapted to sediment disturbance, which would occur naturally on the Nobel Banks during storms. The main impacts would be in the areas directly affected by the dredger s suction device (the draghead), with a lesser impact extending to other areas in the vicinity of the dredging due to the deposition of suspended sediments. The affected areas would recover as they become re-colonised by animals from the surrounding areas. Re-colonisation by animals that are suited to living in disturbed sediments would likely be rapid, but it could take some time for seabed animal communities to become fully re-established. The removal of seabed animals in the dredged areas would result in a reduction in the available food resources. It is considered, however, that this reduction would be small in relation to the potentially available food resources from similar habitats in the area. Important species such as salmon, sea trout skates and rays are able to move away from unfavourable conditions, and impacts on potential migration routes are not expected, given the scale and duration of the dredging operations. The proposed changes to the dredging activities would not have a significant cumulative impact on the natural environment when combined with other activities ongoing in the area. 3.4 FISHING The exclusion of fishermen from the active dredging zones will continue to have a direct impact on fishermen who fish regularly within the licence application area. However no fishermen work exclusively in the area and since dredging operations only take place in a limited number of zones and VIII

12 periods each year, it is considered that the exclusion of fishermen from the area being dredged will not affect the commercial viability of any fishing activities. The main impact to fisheries is the loss of and damage to habitats and benthic (bottom dwelling) communities which are important for commercial species. A small area of seabed will affected and the impacts caused will be temporary. Significant secondary impacts on commercial fish species are not anticipated. The ongoing fishing activities within the proposed licence area already have an impact on fish, shellfish and the seabed habitats. The proposals would result in some further impacts but no significant cumulative impacts on the viability of fisheries are anticipated. There is little reported recreational fishing activity in the area and therefore no impacts are predicted. 3.5 DREDGING AND DUMPING ACTIVITIES There are currently a number of licence application areas under consideration within the Bristol Channel: Area 486 in the outer Bristol Channel immediately south of Nobel Banks, and four areas in the Inner Bristol Channel. Modelling studies have shown that there would be no impacts to ongoing or planned aggregate extraction projects. The dumping operation at Swansea Bay is sufficiently distant not to cause any impact on the quality of dredged material from Nobel Banks. 3.6 SHIPPING AND NAVIGATION Area 476 is close to a shipping lane and the approach channel for Swansea Dock. Vessels passing through this area mainly comprise cargo vessels travelling to and from the north-west and Milford Haven. Other vessels include the Roll-on Roll-off (ro-ro) ferry from Swansea to Cork, which operates 6 days per week in summer and 4 days per week in winter. Normal maritime navigation procedures would be observed and it is predicted that no routine impacts would occur on shipping and navigation in the area. 3.7 INDUSTRIAL AND SUBMARINE MANMADE INSTALLATIONS The only submarine structure within the boundary of Area 476 is the SOLAS Telecommunications cable which runs from Port-Eynon Bay to Kilmore Bay in Ireland. This cable is laid in a south west direction and intersects the eastern and western boundary of the proposed licence area. A 500 m exclusion zone either side of the cable exists and would be maintained during future dredging operations. Effects from sediment transport would not be anticipated from the dredging activities except in their immediate vicinity, and these would not affect the cable route. IX

13 3.8 MARITIME ARCHAEOLOGY AND CULTURAL HERITAGE No records of any wrecks or non-wreck sites (sunken archaeology formerly on dry land) of archaeological importance have been identified within the vicinity of the licence area. No adverse impact on coastal archaeology or historic sites is anticipated from the proposed dredging operations. Impacts on any unknown sites that might be of archaeological and historical importance would be reduced by adoption of the JNAPC Code of Practice in the event of discovery of items or sites. 3.9 MILITARY INTERESTS There are no sites of military interest within or surrounding the licence area and no impacts from the proposed changes to the dredging regime are predicted LEISURE, RECREATION AND AMENITY The Gower Peninsula is an important area for tourism which contributes significantly to the local economy. However, the licence area is approximately 10 km from the nearest point on the Gower coast. The proposed licence area is considered not to be particularly important for small leisure craft and other users such as divers, kayakers and wind surfers The amended dredging operations are predicted not to cause impacts on the physical environment which may have an influence on the tourist and amenity value of the coast eg beaches or water quality. Visual intrusion or noise nuisance from the dredging operations would also not affect tourist and amenity importance. X

14 4 45'0"W 4 30'0"W 4 15'0"W 4 0'0"W 51 30'0"N 51 30'0"N KEY: 4 45'0"W Licence Area SOLAS Telecommunications Cable 500m Exclusion Zone 4 30'0"W Kilometres 4 15'0"W CLIENT: SIZE: TITLE: 4 0'0"W LSDL A4 Figure 1 Area 476 Nobel Banks Licence Area ERM Norloch House 36 King's Stables Road Edinburgh, EH1 2EU Tel: Fax: SOURCE: UK Hydrographic Office and the Controller of Her Majesty's Stationary Office ( All rights reserved. PROJECTION: World Mercator DATE: 15/10/2009 CHECKED: PW DRAWN: JJH DRAWING: APPROVED:MSI PROJECT: SCALE: As Indicative Scale Bar Not For Navigation REV: LicenceArea_Mercator.mxd 0 File: DredgingGIS\Update\MAPS\ES\LicenceArea_Mercator.mxd