BELFAST SEWERS MOURNE CONDUIT. Summary. Summary

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1 WATER & WASTE WATER

2 BELFAST SEWERS Belfast, N.Ireland Value M The Project involved the construction of a new stormwater management sewer, connected by overflow weirs to the existing Victorian network. The new sewer system is 9.4km in length with tunnels ranging in diameters from 1.5m to 4.0m. The Terminal Pumping Station houses the flow to full treatment and storm water pumps. It was constructed using a combination of diaphragm walling and sprayed concrete excavation support. Internal linings were formed using curved jump formwork. A steel framed headhouse was constructed to accommodate the M&E installations along with ancillary structures for screening and treatment equipment. The Project has achieved a Gold award in the Considerate Constructors Scheme. MOURNE CONDUIT Co. Down, N.Ireland Value M Design and Build Contract to replace the existing 35km of the Mourne Conduit from Spelga Dam to Belfast with welded steel pipes 1200mm and 900mm diameter in roads, verges and fields. Also included in the contract was a 6 bay pumping station with140ml/day through a 60m head, Re-valving and refurbishment of existing Service Reservoirs, 0SEC plants and energy recovery buildings. The Mourne Conduit was originally constructed in 1901 and extends 56 kilometres. The existing conduit gravitates with a maximum flow of 147 ML/day through tunnels, siphon pipes and arched concrete conduits. A 140 ML/day pumping station was constructed to pump water to a 4 ML capacity Break Pressure Tank (BPT). Water connections were also provided to the existing off takes with new connections made under the contract. Flow in the section of the pipeline downstream was controlled using Hydraulic Control valves to ensure that the pipe remains full over its entire length at all times. Pressures at the six off takes was controlled using PRVs which were provided under the contract. Other Works included the construction of two smaller pumping stations 10Ml/d and 30Ml/d at off takes and the refurbishment of a Storage Reservoir.

3 FOFANNY WTW Co. Down, N.Ireland Value M Fofanny WTW was constructed to treat up to 52MLD from three different sources, Fofanny Dam, Spelga Dam and Lough Island Reavy. The projects consisted of the following elements, Bulk Excavation of 30,000m3 of boulder clay and rock which was stored onsite for reuse in backfilling the new works, construction of a Buried Reinforced Concrete Structure involving 9,000m3 of structural concrete to enclose DAF, Primary, GAC and Manganese Filter tanks, Pipe work Gallery, Treatment and Sludge Press area, Chemical storage tanks and also a two storey administration block. Construction of two storey Office and Administration area within the buried structure involving general block work, stone work to external walls as well as complete fit out of all internal offices. AQUARIUS 3 Co. Down, N.Ireland Value - 23 M Aquarius 3 was a Design and Build contract for a 23m water treatment works in County Down, Northern Ireland. The 155MLD plant was designed to supply 50% of the water to Greater Belfast and County Down and meet the very latest EU standards. This was one of the largest WTW to be built in Northern Ireland in the last 30 years and incorporated the latest technology to deal with cryptosporidium. BALLYMONEY WWTW Ballymoney, N.Ireland Value M The Civils works involved the diversion of the operational trunk main from Silent Valley to Belfast. Following the excavation of 30,000m3 of rock, a Dissolved Air Flotation Plant was constructed together with a chemical house, filter cells, sludge treatment building and administration block. Extensive landscaping was then used to help blend the works into the surrounding area. Work was completed 8 weeks ahead of schedule and 10% under the target cost, enabling the Client to incorporate a new service reservoir and command reservoir into the scheme. The Ballymoney EU compliance project consisted of the design, construction and commissioning of upgraded waste water treatment facilities at two sites, namely Glenstall WwTW and Ballybrakes WwTW. At Glenstall WwTW (17700PE) new secondary treatment was provided through use of a sequential batch reactor, allowing the existing secondary and tertiary treatment to be decommissioned. Other new works included thin and thick sludge storage, a sludge thickening building, a sludge import/export facility, grease removal and a new MCC building. The existing inlet works and primary settlement tanks were refurbished. Additional sludge treatment was provided through conversion of the tertiary treatment tanks into sludge holding tanks. At Ballybrakes WwTW a new pumping station was constructed to forward FFT to Glenstall. Within the existing treatment site at Ballybrakes, additional storm storage capacity was provided and the treatment facilities decommissioned.

4 ABBERTON PIPELINES PROJECT Colchester, England Value M The Abberton project consisted of a new pipeline, break pressure tank and 4Million Pumping Station which form part of the 150 million Abberton Scheme expanding Abberton Reservoir storage by 58% to help ensure a secure water supply to one and half million people in Essex. Key Facts Construction of more than 32Km of 1200mm spirally wound welded steel trunk pipeline for Northumbrian Water Limited, including ancillary concrete tank construction and M&E works. Combination of two separate pipelines working with the River Stour natural water course in the transfer of 120 Mega Litres per Day, from Newmarket in Suffolk to Colchester in Essex, forms part of the nationally significant Ely Ouse Transfer Scheme. Incorporating major pipeline crossing of fields, minor roads, national highways and the high speed London-Colchester commuter railway line. Including trenchless technology challenges across the spectrum of open face tunnel excavation, closed face Earth Pressure Balancing (EPBM) tunnels, micro tunnelling, and the use of back actor shield tunnel construction. Working in a firm partnership with the Northumbrian Water team, Farrans are projected to deliver the project safely, ahead of programme and significantly lower than the NEC Option C Cost Target. Challenges and steps to success A key challenge was the single crossing of the high speed London Colchester rail line and the 6-lane A12 Highways Agency carriageway. Road and rail closures were not permitted by the Highways Authority and Network Rail for either site investigation or construction. Working closely with the NWL Project Manager and with our specialist partners Jacobs Rail, Ward & Burke and Herrenknecht, Farrans as Principal Contractor co-ordinated the Highways Authority and Network Rail Form A, B, C approval process through comprehensive investigation, liaison and design. The approval and preparation process commenced in October 2010 and culminated in formal approval in May The proposed tunnel was in poor ground conditions including a high water table, a layer of glacial deposits and a railway embankment which Network Rail had classified as marginal to poor. Preparation included the construction of the 8m diameter 14m deep launch and reception shafts by a specialist in situ concrete caisson method eliminating concrete segments and achieving a fully sealed shaft. To ensure that tunnel construction remained within the Form A Settlement Limit (<5mm) Farrans deployed an 1800mm Herrenknecht Earth Pressure Balance Tunnelling Machine (EPBM) in early August The team installed the 150m long x 1800mm diameter tunnel 18m below the railway track and highway in two weeks finishing ahead of schedule and with minimal (<2mm) settlement. The key success in Farrans delivery of the Abberton Pipeline was the proactive approach taken by an experienced and comprehensive management team in delivering such a large scale pipeline in a single year. Key management areas included, proactive approach to landowner liaison, right on time delivery of pipe material from Spain, value engineering of pipe storage areas/road crossings and equipment selection, resource and programme management with productivity rates of up to 1.6km of pipe per week and a comprehensive final field reinstatement, drainage, testing and commissioning plan.

5 DUBLIN WATERMAINS REHABILITATION Dublin, Ireland Value M The DRWMRP is the first regional rehabilitation framework in the Republic of Ireland. Farrans were one of three incumbent contractors carrying out large scale renewal and repair works (www. watermainsrehab.ie). To date, Farrans have delivered Project Management and Construction of 30km of trunk and distribution water mains, 1523 service and meter box renewals, 7100 customer contacts, 1380 trial holes / slit trenches, 3800 reinstatements in City Centre Dublin. PROJECT ALPHA Various, N. Ireland Value - 57 M Project Alpha was the first UK PPP for potable water supply. Northern Ireland Water Limited appointed Dalriada Water Limited, a partnership between Yorkshire Water, Earthtech Engineering and Farrans (Construction) Ltd to design, build, finance and operate five existing water treatment works for a period of 25 years. Upgrade of these treatments works and associated pipelines, which produce 45% of Northern Ireland s potable water, involved a capital investment of 110m over a two year construction phase. N. IRELAND WATERMAINS REHABILITATION Various, N.Ireland Value M Since April 2004, Farrans have been one of two incumbent contractors, in a JV arrangement on the Northern Ireland Water Mains Rehabilitation Project, the first national rehabilitation framework in Northern Ireland. Farrans role incorporates management of detailed design and modelling, planning, programming, roads authority formal notification (Symology) and liaison, networks liaison, HSEQ management, customer notifications, site preparation, pre-chlorination, construction, testing, commissioning, handover and as built drawings. To date more than 705km of water pipeline has been installed on the contract, 598km by trenchless technology. 9,600 service pipe and meter box renewals, 59,000 customer contacts, 30 Works Packages out of a total of 72 zones country wide have been subject to first wave high priority renewal.

6 Farrans Construction Limited Head Office 99 Kingsway Dunmurry BELFAST BT17 9NU T : F : E : construct@farrans.com W :