Environmental Statement - EIB

National Grid Felindre to Tirley pipelineNon-technical summaryProject descriptionMilford Haven GasConnection ProjectsIs there a ‘Do Nothing’option?In addition to the Milford Haven connectingpipeline and the Felindre to Tirley reinforcementpipeline, a number of other projects are required tomeet the gas transmission capacity requirementsarising from the two new terminals. The scheme isshown in the diagram entitled ‘The Milford HavenGas Connection Projects’. These other projects willbe designed and constructed under separateconsent and planning applications.To ‘Do Nothing’ would restrict gas output from thenew gas terminals and place National Grid in breachof its licence as a gas transporter. Both theconnecting pipeline from Milford Haven, which isalready under construction, and the Felindre toTirley reinforcement pipeline are essentialrequirements in order to comply with theseobligations.What type of pipeline?South Wales Reinforcement StrategySouth Wales Reinforcement StrategyThe Felindre to Tirley pipeline will be constructed withhigh grade welded steel and will be buried at least1.2m (4ft) below the reinstated ground surface.National Grid selected the option of a buried crosscountry pipeline as it provides the safest, most secureand practical method of transporting gas, withminimum, medium or long-term physical orenvironmental impacts. National Grid does not favourabove-ground cross-country pipelines because of theirvisual impact, need for frequent maintenance and thefact that they sterilise the land, preventing its use foragriculture or other purposes. A marine or sub-seapipeline solution was also considered, but this wouldhave involved a greater overall length of newpipeline, both on-shore and off-shore, significantenvironmental effects, substantially higher risks andhigher cost.LegislationWho gives permission for the pipeline?National Grid is required to make an application toconstruct the pipeline to the Secretary of State forTrade & Industry under the Public Gas TransporterPipe-line Works (Environmental Impact Assessment)Regulations 1999. This application is supported by theEnvironmental Statement summarised in thisdocument.Above Ground Installationsassociated with the Felindre to Tirley nMilfordHavenHoneybourneCorsePIG Trap TreaddowCorseWormingtonPIG Trap TreaddowTirley WormingtonDerwen FawrPeterstowFelindreTirleyDerwen FawrPeterstowFelindreAberdulaisDyffryn ClydachDyffryn ClydachAberdulaisExisting compressor stationcompressorstationExisting NewcompressorstationExistingcompressorstation site modificationsNew compressor stationBlock valves are comparatively small installationscomprising a fenced area of approximately 0.3ha. Theequipment consists of a number of buried valves thatenable sections of the pipeline to be isolated formaintenance purposes.(94barg)Proposed pipeline 5barg)AboveGroundExisting Existingcompressorstationsite InstallationsmodificationsAboveInstallationsGround InstallationsExisting ProposedAbove GroundTerminalProposed Above Ground InstallationsIntermediate PIG-trap near Three Cocks,PowysProposed pipeline (75barg)TerminalExisting pipeline (70barg)Existing derconstructionExisting pipeline (75barg)(94barg)Pipeline under constructionThe Milford Haven Gas Connection Projects. This diagram shows the projects necessary to extend and reinforce the NationalGas Transmission System to cope with the volume of gas to be imported via the new Liquefied Natural Gas (LNG) terminals atMilford Haven. The new terminals will have the capacity to supply up to 20% of current UK gas demand.3A 30 megawatt (MW) compressor station and PIG-trapare proposed on a site near Felindre. The compressorstation is needed to compress the gas and so maintainthe gas pressure within the Felindre to Tirley pipeline,thus maintaining full flow capacity. It will containelectric and gas powered compressor units andassociated plant and buildings. PIG-traps are facilitiesat each end of a pipeline, and at strategic intermediatepoints along a pipeline’s length, where pipelineinternal gauge devices (PIGs), which clean and allowinspection of the pipeline, are launched and received.Both the compressor station and the PIG-trap will bewithin a fenced area of approximately 5 hectares (ha),with a 4ha operational area.Intermediate block valve site south ofLlanwrda, CarmarthenshireKeyKeyCompressor station and PIG-trap installationat Felindre, north of SwanseaThis PIG-trap installation will comprise a fenced area ofapproximately 0.5ha. and contain two PIG-traps; onefor the receipt of gauges from the start of the pipelineat Felindre and a second to send gauges on to the endof the pipeline near Tirley.Pressure reduction installation atTreaddow, adjacent to the existingPeterstow compressor station,HerefordshireA pressure reduction installation is necessary to enablea connection to be made between the new pipelinefrom Felindre and the existing gas pipeline system atthe existing Peterstow Compressor Station. The totalsite area will be approximately 2ha, of whichapproximately half will contain equipment. It will belocated in a separate fenced area immediately adjacentto the existing compressor station. Because the twopipelines operate at different pressures, the site willcomprise all the equipment necessary to deal with thissituation including pressure reduction valves, a boilerhouse to maintain the gas temperature and gas filtersand meters.Pressure reduction installation and PIGtrap at Corse, in the vicinity of the existingTirley installation, GloucestershireAs with the pressure reduction installation atTreaddow, a connection to the existing gas pipelinenetwork is required at the end of the new pipeline inthe Tirley area. In addition to the equipment necessaryto cope with the difference in pressures between thetwo systems, this installation will contain two PIG-trapsto receive monitoring gauges from the Three CocksPIG-trap installation and to send monitoring gaugesinto the existing gas pipeline system. The installationwill comprise a fenced area of approximately 2ha, ofwhich approximately one third will contain equipment.All of these installations are subject to their ownenvironmental assessment and planning applicationand will be landscaped to minimise visual impact.4

National Grid Felindre to Tirley pipelineIs planning permission required?How is the best route selected?Licensed gas transporters, such as National Grid,are not required to obtain permission from thelocal planning authority for the constructionof underground pipelines. However, planningpermission under The Town and Country Planning Act1990 is required for any associated installations(usually referred to as Above Ground Installations orAGIs). Planning applications for the AGIs associatedwith the Felindre to Tirley pipeline are in the processof being submitted and further details can beobtained from National Grid (freephone 0800 7310561).Several Route Corridor Investigation Studies (RCISs)were carried out to identify, investigate and assesspotential route corridors for the pipeline. Thesewere followed by an extensive series of detailedenvironmental surveys and, in conjunction withlandowner consultation and engineering studies,enabled a preferred route to be selected. Carefulselection of a route is of prime importance inminimising adverse environmental effects.Is an Environmental ImpactAssessment required?As the pipeline will be over 40km in length and willhave a diameter of over 800mm, it falls under Part 1of Schedule 3 of the Public Gas Transporter ations 1999, which states that anEnvironmental Impact Assessment is required.Environmental ImpactAssessmentWhat is an Environmental ImpactAssessment?An Environmental Impact Assessment identifiespotential environmental effects caused by theconstruction and operation of the pipeline in orderthat these can be minimised. It comprises a series ofstudies, surveys and consultations that enables thepipeline to be routed to minimise its effects nt after construction.5Non-technical summarySeveral stages were involved in selecting thepreferred route:1. Identify an Area of Search based on the startand end points of the pipeline;2. Identify potential route corridors (nominally1km wide, within which the pipeline is laterrouted) using desk-based information;3. Select a preferred route corridor;4. Identify a preliminary pipeline route within theroute corridor on the basis of site visits andinitial assessments of available ecological andother information; and5. Identify the final route during theEnvironmental Impact Assessment of theproject using results from a wide range ofdetailed surveys and studies.Part of one of the maps prepared to illustrate the environmental designations and issues along the pipeline route.Information on these designations and constraints is used to help route the pipeline, along with survey informationgathered on site.What are the route constraints?The major environmental and engineeringconstraints that have been considered whenrouteing the pipeline have been: Populated areas – routeing the pipeline awayfrom areas of population; Engineering issues (roads, railways, rivers,cables, other pipelines);The results of this assessment are summarised in theEnvironmental Statement. Construction issues (avoiding steep slopes anddifficult ground conditions);Who is consulted? The safety of construction personnel;As part of the process of preparing theEnvironmental Statement, National Grid has carriedout a series of consultations with numerous keybodies including the Local Authorities, the BreconBeacons National Park Authority, the CountrysideCouncil for Wales, English Nature, Cadw (the WelshAssembly Government’s historic environmentdivision), English Heritage, the Environment Agency(England and Wales), the Welsh AssemblyGovernment, the Department for Trade andIndustry, affected landowners and many localcountryside, farming and conservation groups. Landscape and topography – minimisation ofeffects on the Brecon Beacons National Park,the Wye Valley ‘Area of Outstanding NaturalBeauty’ and other important landscapefeatures and designations including RegisteredHistoric Parks and Gardens; Archaeology – in particular avoidance ofimportant sites; Nature conservation – in particular avoidanceof rare species which are both nationally andlocally important, ancient woodland andupland areas that are difficult to restore suchas heathland and bog; and Mineral extraction and known landfills(avoidance, as far as possible of previousmining areas and suspected contaminatedground).The results of an extensive range of surveys havebeen used to refine the pipeline route during theEnvironmental Impact Assessment process in orderto minimise the pipeline’s effect on theenvironment. These surveys include ecology,hydrology, geology, soils, archaeology andlandscape and have resulted in the avoidance ofapproximately 45 woodlands, 12 unimproved/semiimproved grassland areas and 2 bog areas. Where ithas been not been possible to avoid notable areas,specialist engineering techniques have beenintroduced to minimise the pipeline’s effect.The pipeline routeWhere will the pipeline beconstructed?The pipeline starts near Felindre, a village to thenorth of Swansea and the M4. The pipeline runsnorth, turns briefly westwards, then continuesnorth, passing to the east of Pontarddulais, crossingover the upland common at Cefn Drum, and passingto the west of Ammanford. It then continuesnorthwards passing Llandeilo to the west, where thepipeline swings in an arc around the National Trustowned Dynevor Park estate, crossing the Afon Tywi(River Towy). The route then turns north-eastwardsrunning up the Afon Tywi valley to the west ofLlangadog before turning east to climb onto theupland common at Mynydd Myddfai and MynyddBach-Trecastell, south-east of Llandovery. Thepipeline continues east, passing just to the south ofSennybridge, crossing the Afon Wysg (River Usk) andpassing to the north of Brecon. The route then turnsnorth, then east, passing south of Llyswen and thennorth-east following the Afon Gwy (River Wye)before swinging around Hay-on-Wye to the south.The pipeline then turns south-eastwards, runningpast Dorstone and down the Golden Valley pastPeterchurch and Vowchurch to Kingstone. Thepipeline route then turns east to enter the WyeValley, crossing the River Wye to the north of Rosson-Wye, and continuing east, south of Dymock andStaunton, to reach Tirley.6

National Grid Felindre to Tirley pipelineNon-technical summaryPipeline stringing and weldingThe pipes, which are typically 12 metres or 18metres long are transported onto the workingwidth, offloaded and welded together on thesurface to form long ‘strings’.1Trench excavation and pipeinstallationReinstatementLand drains are installed to reinstate preexisting land drainage patterns. The workingwidth is then cleared, the subsoil ripped torelieve compaction and the topsoil re-laid andcultivated. Temporary bridges at rivers areremoved, hedgerow sections and woodlandbelts replanted and drystone walls andpermanent fences rebuilt. Temporary fencingremains in place until grazing land hasrecovered sufficiently to withstand grazingpressures.The route of the Felindre to Tirley pipeline.Road, rail and river crossingsConstructionWhen will the pipeline beconstructed?Construction is planned to start in spring 2007, withcompletion scheduled for autumn 2007. However,some preparatory works will, subject to thenecessary consents, start before this date.Constru

National Grid is licensed by the Government to transport gas within the UK via its pipeline network. The gas is not owned by National Grid, but the pipeline network provides the means to move it around the country to where it is needed. As a licensed gas transporter, National Grid has a legal duty under the Gas Act 1986(as amended), to