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Airdrie - Bathgate Railway and Linked Improvements Bill Part Four – Assessment of Environmental Effects Design Development Proposal Chapter 15 Water Quality Environmental Statement Page 325

IronsideFarrar May 2006/ 6665

15.0 WATER QUALITY AND DRAINAGE

Summary The proposed railway corridor is situated on a plateau with numerous drains, ditches, watercourses and waterbodies in the vicinity. There are some 30 culverts under the existing rail solum. The proposed drainage for the railway includes retention/ replacement of existing culverts to minimise impacts on water flows within the area, and drainage features providing retention and filtration. Oil interceptors are proposed for station areas to retain hydrocarbon leakage from trains, if this is deemed a risk once the type of rolling stock to be used is confirmed. The railway proposals do not constitute a significant source of pollutants in operation, but care will be required during construction operations to ensure that water resources are not adversely affected by construction materials, silt or by the mobilisation of historical contaminants in the soil or groundwater. Construction phase impacts on surface water quality should be no greater than moderate significance, provided that SEPA pollution prevention guidelines are complied with. Railway operation and maintenance is not expected to impact significantly on surface water quality, flooding or groundwater.

15.1 Introduction 15.1.1 General

This chapter describes the baseline water resource within the corridor of the proposed Airdrie to Bathgate railway and linked improvements to existing track between Bathgate and Haymarket, and identifies potential impacts arising from the operation of the scheme. Mitigation measures forming part of the proposed railway are described and an assessment made of residual impact significance. Construction impacts are addressed in this chapter and are also summarised in Chapter 16 Disruption due to Construction. Surface water features and culvert location are shown in Figure 15.1.

15.1.2 Protection of Water Resources

Water is a valuable resource, which has multiple uses, e.g. potable water supply, waste water disposal, water for agriculture and industry, ecology and conservation, recreation, sport and transport. To help meet these needs, the Government has set standards for river quality. The Scottish Environment Protection Agency (SEPA) is responsible for monitoring, maintaining and enforcing these standards. SEPA is responsible for both the protection of ‘controlled waters’ from pollution and for the prevention of pollution of the environment, harm to human health and detriment to local amenity by waste management activities under the Environmental Protection Act 1990. ‘Controlled Waters’ include all watercourses, lakes, locks, coastal waters and water contained in underground strata (or ‘groundwater’) and it is an offence to pollute such waters, either deliberately or accidentally. In Scotland, all groundwater is protected against pollution caused by certain dangerous substances under the EC Groundwater Directive (80/68/EEC). SEPA have prepared a Groundwater Protection Policy for Scotland (1997), which provides a framework for the management and protection of groundwater in Scotland.



15.1.3 The Water Framework Directive The Water Environment and Water Services (Scotland) Act 2003 transposes the EC Water Framework Directive into Scots Law. The aim of the legislation is to maintain and improve the quality of aquatic ecosystems and requires that deterioration from one status class to another be prevented. Over the coming years, a range of secondary legislation will be developed to provide and confirm the detailed arrangements and mechanisms for the Act’s implementation. This includes the Water Environment (Controlled Activities) Regulations 2005, or ‘CAR Regulations’. These came into force on 1 April 2006, replacing existing environmental regulatory regimes. The Regulations provide for three levels of control (‘authorisations’): 1. General Binding Rules statutory controls over low risk activities 2. Registrations low risk activities that cumulatively pose a risk to the

water environment 3. Water Use Licences provide for site-specific controls and constraints CAR Regulations will control numerous activities, including:

• Engineering activities in rivers, lochs and wetlands;

• Engineering activities in the vicinity or rivers, lochs and wetlands which are likely to have a significant adverse impact upon the water environment;

• Activities liable to cause pollution; and

• Any other activities, which directly or indirectly are liable to cause a significant adverse impact upon the water environment.

Low risk activities controlled by General Binding Rules, include:

• Construction of minor bridges,

• Operating plant or machinery in the vicinity of water, and

• Discharge of surface water runoff, which does not cause pollution of the water environment.

The proposed scheme includes various works, which will fall within the remit of the WFD and CAR. Discussion with SEPA at detailed design stage will be required to address this issue and ensure the appropriate authorisations are obtained. SEPA advises it is minded to authorise the entire railway project under a single CAR licence.

15.2 Methodology 15.2.1 Level of Detail

To ensure the appropriate focus of assessment, water resource impacts are assessed at the following levels of detail, based on the nature and extent of the proposed works on specific stretches of the route:

• Detailed assessment of construction and operational impacts: Airdrie to Bathgate Station - The proposed works between Airdrie and Bathgate comprises the reversion

of the existing cyclepath to railway. This is a major engineering works and includes track-laying, some horizontal and vertical re-alignment and, in one location, land reclamation. New stations will be constructed at Drumgelloch,

Airdrie - Bathgate Railway and Linked Improvements Bill Part Four – Assessment of Environmental Effects Design Development Proposal Chapter 15 Water Quality Environmental Statement 27


Caldercruix, Armadale and Bathgate. Operational and construction phase impacts are identified and assessed.

• Detailed assessment of construction impacts: Bathgate Station to Uphall Station - Between Bathgate and Uphall stations there is already a railway in place, but

works are proposed to restore this to double track and to electrify the line. Construction works will be required for new access roads and car parks at Livingston and Uphall Stations. As the railway solum is already in place, works are not as extensive as those between Airdrie and Bathgate. As the rail line between Bathgate and Edinburgh is already in operation, it is considered that operation of the proposed scheme will have a negligible impact during operation. Construction impacts are possible however, and are assessed.

• Outline Assessment: Uphall Station to Edinburgh - The section of track between Uphall Station and Edinburgh requires only

electrification and some bridge works. Construction phase impacts on water resources are only likely where bridge works are close to a water course or water body. Impacts on water resources in this stretch are not envisaged during scheme operation. An outline assessment of impact was judged to be appropriate for this stretch and is reported in a separate section in this chapter (Section 15.11).

• Tabulated Assessment of Bridge Works Impacts during Construction - Chapter 16, Disruption due to Construction, includes a table listing all works

proposed to bridges along the length of the entire route, and notes any specific water resource issues related to them.

15.2.2 Detailed Assessment Method The detailed assessment of water quality and drainage has been carried out in accordance with the methods set out in the Design Manual for Roads and Bridges Volume 11 Section 3 Part 10. Further guidance on the assessment of scheme impacts on the water environment has been obtained from the Scottish Transport Appraisal Guidance (STAG) and WebTAG (Web-based multimodal transport analysis guidance). In respect of SPP7 Planning and Flooding February 2004, SEPA has identified sites considered to be at risk of flooding. Flood risk assessments at these locations will be carried out at the Detailed Design Phase. A Drainage Study was undertaken by Jacobs Babtie to indicate flows in watercourses crossing the route, and outfall flows from the longitudinal drains. The location of culverts and bridges beneath the existing route was determined by reference to the Ordnance Survey plans, the Scheme Topographic survey, and a walkover inspection. Each existing culvert was checked for capacity by tracing its catchment area, and by using recognised methods to estimate flood flows. Existing culvert capacity was checked against a 1 in 20 year storm flow without surcharge. Impacts on ecology and nature conservation are addressed in detail in Chapter 10. Baseline conditions were determined through the following:

• Site walkover (Airdrie to Bathgate and bridge locations only);

• Liaison and consultation with statutory authorities including: - The Scottish Environment Protection Agency (SEPA) - Scottish Natural Heritage (SNH) - West Lothian Council (WLC) - North Lanarkshire Council (NLC)



- Scottish Water (SW);

• Review and assessment of topographical survey data, drainage plans and geotechnical information;

• Review of Babtie field notes on culvert locations, flow rates and conditions; and

• Review of relevant documentation and guidelines. The significance of impacts on water quality and drainage was determined using the general approach described in Chapter 2.0, i.e. impact significance determined by a combination of receptor sensitivity and impact magnitude. A qualitative assessment of the sensitivity of all water resources was made. This followed the approach suggested in STAG and WebTAG and took into account factors including:

• Water quality;

• Fishery value;

• Recreational value;

• Conservation value;

• Scale;

• Rarity; and

• Substitutability. The detailed assessment is reported in Sections 15.3 to 15.10.

15.2.3 Outline Assessment Method

During the scoping exercise for this Environmental Impact Assessment, significant impacts on water resources arising from the proposed works on the stretch of existing railway between Uphall Station and Edinburgh were considered unlikely. For this reason, the method of assessment was limited to the following:

• Watercourses and waterbodies within the Uphall Station and Edinburgh railway corridor were identified;

• Consultation with SEPA;

• Proposed works reviewed;

• Site visits made to location of all bridge works;

• Note made of areas of ecological importance near potential water resource impacts;

• Note made of any other known issues of sensitivity; and

• Assessment made of likely significance of impact. The Outline Assessment of the Uphall to Edinburgh stretch, including a description of the baseline resource in this location, is reported in Section 15.11.

15.2.4 Criteria for Receptor Sensitivity and Impact Magnitude Table 15.1 overleaf defines the criteria that were used to assign receptor sensitivity.



Table 15.1: Receptor Sensitivity Criteria

Sensitivity Example Criteria

Major • A watercourse with pristine (River Class A1) or near pristine (River Class A2) water quality.

• Water quality which does not affect the diversity of species of flora and fauna

• All sites with international and European nature conservation designations, e.g. Special Protection Areas, Special Areas of Conservation, EC designated freshwater fisheries.

• All nature conservation sites of national importance designated by statute including SSSIs and National Nature Reserves

• Large scale importance of resource

• Rare resource

• Irreplaceable within an acceptable timeframe

Moderate • A watercourse with a measurable degradation in its water quality as a result of anthropogenic factors, a Class B (river)

• Water quality has only limited impact upon the species diversity of flora and fauna in the watercourse

• All non-statutory designated sites of regional or local importance

• Medium scale importance of resource

Minor • Poor water quality resulting from anthropogenic factors, Classes C and D

• Major change in the species diversity of flora and fauna due to the significant change in the water quality

Table 15.2 below defines the criteria used to evaluate impact magnitude: Table 15.2: Impact Magnitude Criteria

Magnitude Criteria Example

Major (adverse) Loss of attribute • Major shift away from the baseline conditions

• Fundamental change to water quality, e.g. downgrading from Class A to C or D, or from B to D

• Loss of an EC designated Salmonid fishery

• Pollution of potable source of abstraction

Moderate (adverse) Impact on integrity

of attribute or loss of part of attribute

• A significant shift from the baseline conditions that may be long-term or temporary

• Results in a change in the ecological status of the watercourse, e.g. downgrading one class

• Loss in productivity of a fishery

Minor (adverse) Minor impact on

attribute • Minor shift away from the baseline conditions

• Changes in water quality are likely to be relatively small or be of a minor temporary nature such that watercourse ecology is slightly affected e.g. minor but measurable change within a class

Negligible Impact will occur but of insufficient magnitude to affect the use/ integrity

• Very slight change from the baseline conditions such that no discernible effect upon the watercourse’s ecology results

• No change in classification

• No increase in flood risk

15.3 Limitations to Assessment

This assessment of water quality and drainage is based on the proposals for the Airdrie to Bathgate railway line as made available to Ironside Farrar Ltd at the time of assessment. This includes electrification and re-doubling works to the existing track between Bathgate and Haymarket, and new stations at Drumgelloch, Caldercruix, Armadale and Bathgate, with station upgradings at Airdrie, Livingston North and Uphall. At the time of writing, details of station drainage SUDS features were not



available. The proposed works are described in Chapter 3 of this Environmental Statement.

15.4 Baseline Conditions: Airdrie to Uphall Station

The study area for surface water impacts was defined for the purposes of this impact assessment as being 250m either side of the scheme and further downstream where required. Groundwater impacts were considered up to 1000m either side of the scheme. These distances are in line with other major railway studies, including Environmental Studies on the ECML and West Coast Route modernisation. Figure 15.1 illustrates the water resources of the area and shows the location of culverts beneath the solum.

15.4.1 Surface Watercourses

The following watercourses are described in a west to east order, as they cross or run close to the railway. The topography of the route is generally flat and marshy, with watercourses poorly defined. There are several un-named burns or ditches within the study corridor and these are considered as a group at the end of this section. Table 15.3 lists water quality, where known, and the sensitivity of the water feature. North Calder Water

This watercourse flows from Black Loch in the north, passing close to the proposed scheme/ existing cyclepath just prior to entering Hillend Reservoir. From the reservoir it flows to the southwest, passing under the existing railway solum at several locations: 1. At Ford Bridge to the east of Plains (UB10) 2. At Bleachfield Cottages to west of settlement ponds at Caldercruix (Culvert 3) 3. Just before the railway crosses the B825 at Hillend (UB5) SEPA describes the water quality of the North Calder Water and its tributaries as ‘Good’. The mean flow at Hillend is 0.35m

3s-1. Flow downstream of Hillend Reservoir

is controlled by a flat V fibre-glass Crump weir as the watercourse leaves the reservoir. The North Calder Water is susceptible to minor weed growth in summer in this location, and the channel is very occasionally flooded out at extremely high flows. North Calder Water passes close to a disused tip and a scrapyard to the west of Caldercruix. It also receives outflow from the Caldercruix settlement ponds, and both Caldercruix and Plains sewage treatment works. North Calder Water has a history of industrial use, in part due to the fact that Forth and Clyde Navigation controlled the flow of water along it as early as 1799 with the building of Hillend Reservoir. The industries along the river were concentrated at Calderbank, Moffat Mills, Gartness, Caldervale, Plains and Caldercruix. The last mill to disappear was Caldercruix paper mill in 1970. There are several un-named minor burns or drainage ditches culverted under the railway solum in the vicinity of the North Calder Water. A culvert survey has been undertaken (Babtie, 2003) to identify the location, condition and flow of all culverts crossing the route (Appendix 6). Culverts 1 and 2 may feed into its system, as shown in Figure 15.1. Un-named watercourses are described under that heading further on in this section.



Mill Lade A mill lade has been formed from part of the North Calder Water as it flows out of Hillend Reservoir and passes under the B825. This mill lade passes under the railway viaduct in parallel with the North Calder Water and flows towards the west adjacent to the A89, terminating just past the junction of the A89 with Caldercruix Main Street. There is a large volume consented discharge into the Mill Lade from the Hillend quarry. Lilly Burn/ School Burn This burn forms the outflow from Lilly Loch, flowing to the northeast, passing under both the A89 and the railway via Culvert 5 before entering the Hillend Reservoir. Representatives from the Airdrie and District Angling Club advise that this is a spawning trout river. Bracco Burn This flows northwards from the Forrestburn Reservoir, passing Nether Bracco Farm and flowing under both the A89 and the railway via Culvert 6 before entering the Hillend Reservoir towards its eastern end. Representatives from the Airdrie and District Angling Club advise that this is a spawning trout river. Barbauchlaw Burn This watercourse flows from the southwest, and is crossed by the railway at underbridge UB3 just to the west of the Standhill Farm road. It passes to the south of Blackridge in parallel to the railway before turning northeast under the A89 and out of the study area. SEPA advise that this burn has Class C (poor) water quality. Downstream of the study corridor (some 450m to the north of the proposed alignment), this burn and its environs is a designated Scottish Wildlife Trust site, described as a stream with a variety of habitats (see Chapter 10 Ecology for further information). Black Moss Burn This burn flows eastwards, arising to the south of the spoil heap and tip south of Westrigg. It flows in parallel and to the south of the railway before passing under it twice via culverts 16 and 17 near where the railway crosses the minor road between Armadale and the B718 via Northrigg Farm. Bog Burn/ Bathgate Water The Bog Burn flows from the east in a northwest direction through a wooded area and pond cluster (Bog Burn Flood Lagoons SWT wildlife site) in the south of Bathgate. It passes in culvert under the operational railway adjacent to the A779 Starlaw overbridge and flows adjacent to the railway at Inch Wood. It passes under the solum again at the Boghead Bridge, where it becomes known as the Bathgate Water, and flows on in a northerly direction past the cemetery at Paulville. The Bog Burn has Class C (poor) water quality at Whiteside. Boghead Burn

This flows northeast, approximately parallel to the railway as it approaches Bathgate, then turns eastwards to feed into the Bog Burn Flood Lagoons and the Bog Burn. This watercourse has Class C (poor) water quality at Standhill Farm bridge.



Lochshot Burn Tributary This small burn passes under the existing railway at the east end of Tailend Moss nature reserve, and runs southwards to join the Lochshot Burn which ultimately feeds into the River Almond. Water quality is unknown. Deans Burn This watercourse passes under the railway south of Deans, at Eliburn, Livingston. It flows to a waterbody at Eliburn, some 450m to the south. Flow from this waterbody converges with the Lochshot Burn and ultimately meets the River Almond. Water quality is unknown. Beugh Burn This small burn is culverted under the railway where the railway is crossed by the A899-M8 junction. It flows eastward and ultimately joins the Broxburn. Water quality is unknown. 2004 SEPA data show the Beugh Burn to be of poor quality (C) on a 3.3km stretch at Pumpherston (1.5 km downstream of railway crossing). Un-named watercourses The Initial Technical Feasibility Study (Babtie, 2003) has identified 30 culverts conveying water beneath the disused railway solum, with a further five new culverts identified required. Two drainage ditches/ small burns flow south to join the North Calder Water, flowing under the railway on the eastern outskirts of Airdrie just east of where a dismantled line branches to the south. A burn runs from the north, passing under the railway to the west of Caldercruix to feed into the settlement ponds to the south of the railway. The outflow from the ponds feeds to the North Calder Water. To the east of Bracco Burn, a small burn/ drainage ditch flows northeast from the Forrestburn Reservoir, passing under both the A89 and the railway before entering the Hillend Reservoir at its eastern end. A series of field drains lead from the north side of the railway along field boundaries within the Forrestfield Moss area to reach the North Calder Water as it flows in to the Hillend Reservoir. One field drain leads eastwards from the settlement ponds at Cairneyhill quarry to the disused Forresthill Quarry before turning north and passing under the A89 and then the railway. At Bedlormie Toll where the proposed railway crosses the A89, a field drain passes under the railway, flowing in a southerly direction. Five further field drains/ small burns pass under the railway between Bedlormie Toll and Blackridge. These drain to the south, to Forrestburn Water and Forrestburn Reservoir. The southern boundary of the reservoir is low lying and boggy, with small ponds shown on OS map. Much of the land to the south of the railway between Garrieston and Bathgate is marshy. Table 15.3 overleaf summarises water quality and receptor sensitivity.



Table 15.3: Watercourse Quality and Receptor Sensitivity

Water Course Quality Comments Sensitivity

North Calder Water upstream of Hillend Reservoir

Good Flows into trout fishery and recreational waterbody SINC

Major

North Calder Water downstream of Hillend Reservoir

Good Receives effluent from Caldercruix and Plains STW. Tips and scrapyard in catchment

Moderate

Mill Lade Unknown Minor

Lilly/ School Burn Unknown Spawning trout. Flows into trout fishery and recreational waterbody

Major

Bracco Burn Unknown Spawning trout. Flows into trout fishery and recreational waterbody

Major

Barbauchlaw Burn C Poor SWT site downstream Moderate

Black Moss Burn Unknown No known fishery/ recreational/ amenity use

Minor

Bog Burn/ Bathgate Burn

C Poor Passes through Bog Burn Flood Lagoons. SWT site

Minor

Boghead Burn C Poor Feeds into Bog Burn Flood Lagoons SWT site

Minor

Lochshot Burn Tributary Unknown No known fishery/ recreational/ amenity use

Minor

Deans Burn Unknown No known fishery/ recreational/ amenity use

Minor

Beugh Burn C Poor No known fishery/ recreational/ amenity use

Minor

Un-named burns and ditches

Unknown No known fishery/ recreational/ amenity use

Minor

15.4.2 Surface Waterbodies

Hillend Reservoir Hillend Reservoir lies 1 km to the east of Caldercruix and is adjacent to the railway. At 140 hectares it is the largest waterbody in North Lanarkshire. It was constructed in 1799 and at the time was one of the biggest man-made reservoirs in Scotland. The reservoir supplies water to the Forth and Clyde and Monkland canals. Water levels within the reservoir can drop by as much as 2m in the summer months. SEPA describe water quality as ‘Good’, although there is a sign warning of blue algae at the road entrance to the Hillend Sailing Club which suggests it is subject to periodic water quality problems. The reservoir is designated as a SINC (see Chapter 10), supports a trout population and is one of the best angling lochs in Central Scotland. Between October and April it also supports ducks and geese. The reservoir is owned by British Waterways and is part of North Lanarkshire Council’s Leisure and Recreation in the Countryside scheme. Eastercroft Nursing Home, on the A89, has a consented discharge into the reservoir from a biological treatment plant. The iron outfall pipe extends only 1m or so into the reservoir. The Airdrie and District Angling Club use the reservoir for trout fishing. The Clubhouse is situated on the southeastern shore of the reservoir, adjacent to the disused railway line, with the carpark located between the railway and the A89. They have some 500 paying members, and there can be up to 350 anglers on the reservoir. Special ‘wheelyboats’ are available to allow disabled anglers to access the reservoir. The Club restock the reservoir with trout every two weeks, spending some £20,000 to £35,000 every year.



The reservoir is also used for dinghy sailing. The Hillend Sailing Club is located near the dam on the west end of the reservoir. Lilly Loch Lilly Loch is some 600m from the proposed railway alignment at its nearest point. It is fed by Browns Burn from the south west, and outflows via a weir to the northeast, where it forms School Burn. Lilly Loch is designated as a SINC. The SINC boundary extends to the side of the track and takes in Wester Bracco and Moffat Hills. Lilly Loch is used by Clarkston Angling Club. Various small ponds and bogs

• Caldercruix Moss SINC

• Caldercruix Lagoons (Bleachfield Marsh SINC)

• Ponds and marshy areas along southern boundary of Hillend Reservoir, adjacent to the railway

• Forrestfield Moss

• Millbank Quarry ponds to south of railway at Blackridge

• Bogburn Flood Lagoons south of Bathgate

• Blawthorn Moss (SAC)

• Tailend Moss Caldercruix Moss, adjacent and to the west of Hillend Reservoir, has been designated as a Site of Importance for Nature Conservation (SINC) for its plant species. Caldercruix Paper Mill was the largest producer of rag blotting paper in the world. All that remains today are the old settling ponds just opposite the artwork called Legs. The ponds have become filled with sediment and residue from the paper making process, and now mainly consist of discoloured, boggy marsh, although the westernmost pond often contains standing water. The settling ponds (lagoons) form part of the Bleachfield Marsh and North Calder Water SINC. The southern boundary of Hillend Reservoir is low lying and boggy, with small ponds shown on OS map. Much of the land to the south of the railway between Garrieston and Bathgate is marshy. Impacts on this area are considered within the section on Hillend Reservoir, as it is assumed the water resource is in continuity with the reservoir. There is a small, 2-part SINC, Garrieston West, close to the southern boundary of the reservoir, at its easternmost section. Beyond Garrieston West SINC, the railway passes through Forrestfield Moss. This moss is likely to be in hydrological continuity with the North Calder Water and Hillend Reservoir. Blawthorn Moss is a National Nature Reserve, a Site of Special Scientific Interest and a Special Area of Conservation covering an area of 109ha. It is one of the larger, least-disturbed active raised bogs in Scotland’s central belt. This habitat is a primary reason for selection of the site as an SAC. It is 1km to the north of the proposed railway. It is likely to be in hydrological continuity with some of the burns flowing to the south and culverted under the railway. Raiziehill Moss is small raised bog to the west and southwest of Blackridge, straddling the proposed railway alignment. It is a designated Scottish Wildlife Trust site.



Bogburn Flood Lagoons is an area of lagoons associated with a Lothian Region flood alleviation scheme. The area is a designated Scottish Wildlife Trust site, and is used by protected species watervole. The proposed railway alignment is some 250m from the nearest boundary of the lagoons site, but may lie within its catchment in parts. Tailend Moss is a nature reserve located adjacent and to the south of the operational rail line between Bathgate and Livingston. It is one of the last remaining raised peat bogs in Lothian and has been a Scottish Wildlife Trust reserve since 1979. In addition to raised bog there are a variety of ponds and marshes, which together hold varied breeding and winter bird populations. Table 15.4: Waterbody Quality and Receptor Sensitivity

Waterbody Comments Sensitivity

Hillend Reservoir Trout fishing Dingy sailing SINC

Major

Lilly Loch SINC Trout fishing

Moderate

Blawthorn Moss SAC, National Nature Reserve, SSSI Major

Caldercruix Moss SINC Moderate

Caldercruix Lagoons Mostly contaminated marsh SINC

Minor

Ponds/ marsh on S boundary of Hillend Reservoir

In continuity with Hillend Reservoir SINC in part

Major

Forrestfield Moss In continuity with North Calder Water and Hillend Reservoir

Moderate

Raiziehill Moss SWT Moderate

Millbank Quarry Ponds - Minor

Bogburn Flood Lagoons Supports water vole SWT site

Moderate

Tailend Moss SWT site Moderate

15.4.3 Groundwater Features BGS sheet 31 shows that the rail line is underlain by strata from the Middle Coal Measures and basalt at various locations along its route (see Chapter 7 for details of route geology). SEPA’s Groundwater Protection Policy classifies basalt as moderately permeable. These are fractured rocks that do not have a high primary permeability. Although these formations will seldom produce large quantities of water for abstraction, they are important for local supplies and in supplying base flow to rivers. SEPA advises that the route crosses superficial and bedrock aquifers which may be highly vulnerable to pollution. Portions of the route to the south and west of Hillend Reservoir, in Armadale and in Bathgate have been given the highest classification for groundwater vulnerability. Groundwater is relatively shallow along the route. It may also be present in the glacial till and perched groundwater may be present in lenses. Groundwater was encountered in four trial pits (TPC 19, 22, 31 and 33) at depths ranging from 0.8m – 2.7mbgl (Earthworks, Mineral and Geotechnical Surveys, Babtie, June 2004). All chemical samples were couriered to City Analytical Services Ltd (CAS) in Coventry for laboratory analysis.



Table 15.5 below shows the analysis data for water samples collected from a trial pit within the route. The data indicate that the water sample from trial pit TPC 19 fails on several of the selected chemical species tested, although it is understood that the limits used are for drinking water, and are thus particularly stringent. It should be noted that groundwater samples collected from trial pits do not provide a reliable representation of the groundwater quality, and the information reproduced here is preliminary information only which could assist in the design of subsequent groundwater monitoring. Section 15.4.5 describes contamination present within the route corridor.

Table 15.5: Water Chemical Results – TPC19 at 0.80mbgl

Chemical Parameter Units Concentration Guideline

Value Guidance

Publication Pass/ Fail

Aluminium mg/l 0.55 0.2 EA FAIL

Arsenic µ g/l 2.00 10 EA PASS

Boron mg/l 0.06 1 EA PASS

Cadmium µ g/l <detection limit 5 EA PASS

Calcium m g/l 34.00 250 EA PASS

Chromium (total) µ g/l 6.03 5 EA FAIL

Chromium (Hexavalent) µ g/l 111.00 - - -

Copper µ g/l 33.00 1 EA FAIL

Iron mg/l 2.40 0.2 EA FAIL

Lead µ g/l 27.00 4 EA FAIL

Magnesium mg/l 4.80 50 EA PASS

Manganese mg/l 0.09 0.05 EA FAIL

Mercury µ g/l <detection limit 1 EA PASS

Nickel µ g/l 12.00 20 EA PASS

Potassium mg/l 4.70 12 EA PASS

Selenium µ g/l 1.14 10 EA PASS

Sodium mg/l 310.00 170 EA FAIL

Zinc µ g/l 31.00 8 EA FAIL

Cyanide (Free) mg/l 0.05 50 EA PASS

Cyanide (Total) mg/l 0.05 50 EA PASS

Sulphate g/l 0.10 0.25 EA PASS

Alkalinity as CaCO3 mg/l 100.00 - - -

Ammonia as N mg/l <detection limit 0.015 EA DL insuff.

Dissolved Solids mg/l 111.00 - - -

Electrical Cond. µS/cm 1400.00 - - -

Sulphide mg/l <detection limit 0.00025 EA DL insuff.

Total Organic Carbon mg/l 13.00 - - -

pH Units 7.60 - - -

TPH µ g/l 40.00 10 EA FAIL

PCB µ g/l <detection limit -- - -

PAH µ g/l 0.46 0.1 EA FAIL

The disused railway line between Airdrie and Bathgate passes through various historical mining communities which served numerous collieries within the area. A number of disused mineral lines divert from the main track to these mining areas generally located adjacent to the north and south of the main line. Babtie Group acquired from The Coal Authority (CA) mine abandonment plans, and mine entry reports (reproduced in Appendix B) within a 100m corridor of the railway. Reports received from the CA have highlighted that a total of 34 mine entries are approximately located within 50m either side of the track and occasionally on or beneath the original track formation. The proposed relocation of the cyclepath is shown to be potentially affected by up to 8 mine entries, 7 of which are shafts and an adit. Groundwater will flow through these worked areas, although flow rates and levels are unknown at present.



Groundwater within the proposed railway corridor is considered to be of moderate sensitivity to contamination and to impacts on flow.

15.4.4 Flooding The following paragraph is extracted from Jacobs Babtie’s June 2004 report ‘Earthworks, Mineral and Geotechnical Surveys’. Some areas along the disused track and the proposed cyclepath diversion are prone to flooding particularly west of Blackridge at Standhill Farm where the track is flooded by run-off from the higher ground to the south, and also west of Hillend Reservoir. Sustrans have recently installed drainage along the route between Hillend Reservoir and the underbridge over the B875 east of Caldercruix. The present level of the track at this location is below the surface level of the surrounding bog land and also of Hillend Reservoir suggesting this area may also be prone to flooding. The proposed cyclepath diversions are prone to flooding south of Hillend Reservoir near Eastercroft Nursing Home and also northeast of Trees Farm where the proposed route crosses over an extensive peat bog. Here an existing path is showing visible signs of excessive differential and vertical settlement. This area is also the location of an abandoned coal pit, which may be at least partly responsible for the flooding in the area: iron staining was certainly of note between this path and the track. Flooding is also addressed in the Jacobs Babtie Drainage Study of March 2006. This noted that the topography of the route is generally flat and marshy, with watercourses poorly defined. Some crossing drain headwalls were heavily overgrown and unidentifiable, and some low areas did not appear to have an appropriate crossing drain. Each existing culvert was checked for capacity by tracing its catchment area, and by using recognised methods to estimate flood flows.

100 year Flood Risk Maps obtained from SEPA show the proposed route to pass through an area of flood risk to the west of Caldercruix. The Barbauchlaw Burn south of Blackridge is prone to flooding at Under Bridge 3. SEPA considers the following sites to be at risk from flooding based on the Centre for Ecology and Hydrology (CEH) mapping:

• railway crossings of the North Calder Water between Hillend Reservoir and Plains; general flooding of the area between Hillend Reservoir and Plains;

• potential flood risk from the Hillend Reservoir due to overtopping, wave action and loss of stability of any retaining walls, etc;

• the area surrounding the Gatehouse at Hillend Reservoir;

• east of Bracco Wood, alongside Hillend Reservoir; and

• the crossing of the Barbauchlaw Burn at Standhill Farm, west of Blackridge. SEPA advises that the CEH indicative 1 in 100 year return period flood maps have been generated using a generalised technique on catchment areas greater than 10 sq.kms and should not, by themselves, be used to infer that specific areas are, or are not, at risk of inundation. The method specifically excludes flood defences. SEPA considers the following sites to be at risk from flooding based on data from the Strathclyde Regional Council Water Services Committee (January 1995):

• Old Bore Road, Airdrie. Flooding occurred during the 11-12 December 1994 event. This site may be subject to regular flooding;



• Station Road, Airdrie. Flooding occurred during the 11-12 December 1994 event. This site may be subject to regular flooding;

• Eastfield Road, Caldercruix. Flooding occurred during the 11-12 December 1994 event.

SEPA advises that there are also sites not shown on the CEH maps but which are adjacent to a watercourse and consequently may be at risk of flooding. SEPA holds no data pertaining to non-fluvial flooding and is therefore unable to comment thoroughly on the flood risk in the built-up areas within this application.

15.4.5 Contamination The study corridor’s previous use as a railway suggests that there may be some contaminated land present. There is contamination visible in the Caldercruix settlement lagoons, presumably related to the former paper mill activities. There are also areas of the route where fly-tipping occurs and the route runs through some areas of industrial activity, mainly at Airdrie and Bathgate. Preliminary contamination testing identifies low risks to human health and the environment but notes hotspots of contamination cannot be discounted in some areas (Earthworks, Mineral and Geotechnical Surveys, Babtie Group, June 2004). Table 15.5 illustrates contamination present in groundwater along the route. Ground contamination is addressed in detail in Chapter 7 Geology and Soils.

15.4.6 Existing Drainage Surface Water The proposed route follows the existing rail alignment between Drumgelloch and Bathgate, now largely converted to cyclepath. East of Bathgate, the route continues on operational track. Surface water drainage at present consists of cess drains (a form of French drain) on either side of the track for much of its length. Between Airdrie and Uphall, these outfall to some 20 discharge points, either into culverts which then outfall to watercourses, or directly into watercourses. Where there are no cess drains present, surface water runs off the hard-surfaced track and percolates through the original railway ballast material. It will then make its way to groundwater or to the nearest watercourse/ waterbody. The location of culverts and bridges beneath the existing route was determined by reference to the Ordnance Survey plans, the Scheme Topographic survey, and a walkover inspection by the Jacobs Babtie Drainage Engineer. A schedule of these is included in Appendix 6. Each existing culvert was checked for capacity by tracing its catchment area, and by using recognised methods to estimate flood flows. Foul Drainage SEPA advises that there are 17 discharge consents within 1km of the railway corridor on the Airdrie to Bathgate stretch. These include the Blackridge Sewage Treatment Works, four septic tanks and surface water from a number of industrial establishments. There are consented discharges to Hillend Reservoir from Eastercroft Nursing Home and to the Mill Lade from Hillend Quarry. Scottish Water has several large diameter sewerage services crossing and running parallel to the line. Drainage pipes cross the railway as it enters Bathgate: at the Bog



Burn crossing, just to south of Bog Burn crossing, from the Golf Club house access road to meet Edinburgh Road, and at the council yard just to the west of where the railway passes under the B792. SEPA advises that there are likely to be unrecorded sewer tails within the scheme corridor.

15.5 Proposed Drainage Arrangements

A drainage scheme has been designed for the proposed twin track rail between Airdrie and Bathgate. The proposed scheme includes:

• Longitudinal drainage or Cess drains and Cut-off Drains, and

• Culverts carrying watercourses beneath the route. The drains and catchpits were designed in accordance with Network Rail’s, Company Standard RT/CE/C/006 (October 2002) ‘Design, Installation, and Maintenance of Lineside Drainage’. Drainage arrangements for the operational track east of Bathgate will be the same as at present, with no changes proposed. SEPA request that surface water drainage is treated in accordance with the principles of Planning Advice Note 61 and “Sustainable Urban Drainage Systems Design Manual for Scotland and Northern Ireland”, CIRIA C521 (http://www.ciria.org.uk). This would include run-off from access roads, car parks, construction works, roofs, areas of hardstanding and point source discharges from stations and along the length of the track. The finalised surface water drainage arrangements for the various works should be agreed with SEPA’s regional Environmental Protection and Improvement Teams.

15.5.1 Longitudinal drain design ‘Cess drain' or ‘collector drain’ refers to a drain that collects surface and sub-surface water. These drains run adjacent to the railway, and parallel to it. They will be of French Drain type construction i.e. a perforated pipe, with a granular backfill, with a geo-membrane on the sides to prevent silt infiltration. There is however, no membrane on the top of the drain to allow free ingress of runoff, including some silt. Cess drains have been designed to discharge into every watercourse crossed by the route. Drains will be located on both sides of the twin track. Within the cess, invert levels are set to be a minimum of 300mm below existing ground level. The cess drains are a minimum distance of 1.41m from the rail running edge to the face of the drain trench or catchpit. Cess drains will not normally be provided on embankments.

Manholes are located at 30m intervals and a silt trap is provided at each. The design for longitudinal drains is based on a 1 in 5 year design storm.

15.5.2 Cut-Off Drains Cut-off drains or ‘field drains’ are considered necessary for cuttings more than 2m deep where surrounding land drains to the cutting. The cut-off drains are designed to be a minimum 100mm diameter with a minimum cover of 500mm. Cut off drains will be of the same construction type as the collector drains and will follow the lie of the land where appropriate with a cover of 0.5m. The flow in the cut-



off drain will generally be discharged into the collector drain via the cutting slope where convenient, or directly into water courses. Cut-off drains are located at the top of cutting slopes, and at the base of embankments in the following locations, but not elsewhere:

• Where the adjacent land inside the railway fence slopes towards a cutting more than 2m deep; and

• Where adjacent land inside the railway fence slopes towards any embankment more that 2m deep.

15.5.3 Drainage Outfalls Outfalls are provided at every existing culvert or watercourse crossing the line of the railway.

15.5.4 Crossing Drains & Culverts

’Crossing drains’ run perpendicular to the track (so as to have minimum drain lengths under the track). They have a minimum cover of 1.1m from the pipe soffit to existing ground level. Where existing culverts were found to have insufficient capacity at a 1 in 20 year flood, or where an existing culvert could not be positively identified, provision has been made for a new culvert. New culverts have been designed to pass a 1 in 200 year flood without surcharge, as suggested by SEPA, since the cost of this increased provision is marginal. New culverts will meet requirements with regard to the passage of migratory fish.

15.5.5 Station Area Drainage

Four new stations will be constructed at Drumgelloch, Caldercruix, Armadale and Bathgate. These would include new platforms, waiting shelters and car parking areas. Car parking areas will have SUDS drainage features to attenuate and treat surface run-off, and oil interceptors will be incorporated in station track drainage, if required through rolling stock selection. SEPA advises that run-off from service yards, maintenance bays and waste storage areas should be connected to the public foul sewer. This assessment assumes that foul drainage facilities, where required, will be incorporated into the new stations and piped into the existing Scottish Water sewerage system. The Bathgate light maintenance depot will have a retention tank for waste from the Controlled Emission Toilets. This will discharge into a foul drain at a rate to be agreed. Scottish Water has confirmed that the existing sewerage network can incorporate the additional capacity. Proposals to upgrade stations at Airdrie, Livingston North and Uphall also include SUDS drainage features. At the time of writing, details of station SUDS features were not available. SEPA recommends minimising areas of hard standing wherever possible in line with the SUDS philosophy of mimicking natural drainage. This would include using permeable surfaces for car parking. SEPA advises SUDS should be designed as a habitat enhancing landscape feature to maximise the wildlife value as illustrated in the SEPA publication ‘Ponds, Pools and Lochans’.

15.5.6 Interceptors



Interceptors are not generally required on railway drainage systems, since the run-off is filtered through the ballast and drain surround. However, where there are sensitive watercourses, interceptors will be provided to retain any hydrocarbons leaking from trains, if this is deemed a risk once the type of rolling stock to be used is confirmed.

15.5.7 Cyclepath Drainage Separate drainage arrangements are proposed for the cyclepath. This will be subject to detailed design however will consist of either: (i) Ditches (ii) Filter drainage (iii) Infiltration Trenches The form of drainage would be influenced by the topography, outfall location, corridor with and ground conditions. Outfalls would be to local watercourse/ ditch or through infiltration depending on the GI results on ground porosity. Where there is a large catchment outfalling to a sensitive watercourse attenuation for peak runoff may be required depending on the form of drainage. New headwalls would also be required at each outfall. With regard to the receiving watercourses hydrological studies may be required to assist in determining the allowable discharge rate.

15.5.8 Construction Compound Drainage

Foul drainage from construction compounds will be contained and disposed of in an appropriate manner. Network Rail has stringent standards with regard to welfare facilities that must be provided by contractors for their staff. Minimum facilities will be sealed chemical toilets, with the preference being to connect into the public foul sewer where practicable. The specific requirements at each location will be addressed in detail through the Code of Construction Practice.

15.6 Potential Issues The proposed scheme is to re-instate the Airdrie to Bathgate section of the railway largely on the existing solum, and to maintain provision for cyclists either adjacent to the track or on nearby minor roads/ paths. The track between Bathgate and Livingston Uphall is operational at present, but some sections are single track and will require upgrading to twin track. The existing solum is of an adequate width to accommodate the proposed track doubling. The proposed works between Bathgate and Uphall will therefore be relatively minor, with far less potential for impacts on water and drainage than works on the western section of the railway. The section of track between Uphall Station and Edinburgh requires only electrification and some bridge works. Construction phase impacts on water resources are only likely where bridge works are close to a water course or water body. Impacts on water resources in this stretch are not envisaged during scheme operation. An outline assessment of impact was judged to be appropriate for this stretch and is reported in a separate section on this chapter (Section 15.11). The entire route will be double-track and electrified throughout. Appropriate signalling and telecommunications systems will be installed along the route. There will be minor vertical and horizontal re-alignments in some places.



It is anticipated that thirteen temporary works compounds (construction depots) will be used during construction (see Chapter 16 Disruption Due to Construction). All of these are located adjacent to the Airdrie to Bathgate stretch. Some of the compounds are adjacent to a water resources feature. These compounds pose a theoretical risk of spillages and contamination. Their impacts on specific water features are considered in this chapter, with Chapter 16 providing a compound-by-compound assessment. The route passes through some flood-prone areas, crosses numerous burns and ditches and runs adjacent to the southern bank of Hillend Reservoir. The route is adjacent to/ passes through two Scottish Wildlife Trust Nature Reserve sites and a SINC. The proposed cyclepath and a new road access to Airdrie and District Angling Club will require land reclamation works at Hillend Reservoir, and casting jetties will require to be constructed into the reservoir in order to maintain a safe distance between anglers and the railway/ cyclepath. Remedial works/ replacements will be required for the majority of the numerous bridges, culverts and retaining walls along the route. A new road bridge accessing Caldercruix Station car park will be constructed over the North Calder Water. Eight new footbridges carrying a combined footpath and cyclepath are to be constructed over watercourses on the realigned cyclepath route. The installation of signalling and telecommunications, route electrification, station construction, horizontal and vertical realignments, etc will give rise to a significant volume of earthworks within the study corridor. Areas of potentially contaminated land have been identified within the study corridor, and earthworks within these locations may mobilise pollutants, allowing them to contaminate surface or groundwater. The location of the car parking area for the station at Caldercruix will encroach on 3 of the 5 contaminated settlement lagoons. These are thought to be in hydrological continuity with the North Calder Water. There is the potential for pollution from track and station areas, including grease and oils from trains, and surface water runoff from station buildings and roads/ hardstanding areas. Any new station car parks and associated areas of hardstanding will increase the area of impermeable surfaces. This will reduce the infiltration of rainwater to the ground and can increase flows to surface water following rainfall. Potential impacts on water quality and drainage in summary comprise:

• Construction Phase: - Earthworks may mobilise pollutants in soil and allow them to contaminate

nearby water resources through surface water run-off and percolation to groundwater

- Earthworks may pollute nearby watercourses with sedimentary material or construction materials

- Construction/ remedial works to bridges and culverts may allow sediment/ construction materials to pollute watercourses

- Accidental physical damage to banks/ stream beds may affect flow characteristics

- Risk of spillage of construction materials from contractor’s compounds - Temporary diversion of watercourses to allow bridge and culvert repair/

construction work to take place may affect the migration of salmonids or generally impact on the ecological quality of the watercourse

- Land reclamation and bank protection works in and adjacent to Hillend Reservoir pose a risk of inadvertent contamination by silt and construction materials

- Contaminated groundwater may pollute surface water bodies - Grouting works may impede groundwater flow within mine workings



• Operational Phase - Contaminants in run-off/ leachate seepage from track could reach nearby

surface waters or migrate to groundwater - Herbicide use on trackside vegetation could migrate to groundwater or

nearby surface waters - Bridge and structure maintenance poses a risk of inadvertent contamination

of nearby watercourses with paint, cement etc - Altered track drainage arrangements such as new outfalls may alter flow

characteristics of receiving watercourses - Altered track drainage arrangements may alter water levels in surrounding

marsh/ bog areas - Culvert clearing may increase flows under the solum - Culvert clearing and new drainage may alter drainage pattern of flood plain - New station areas and car parks will increase the area of impermeable

ground and thus volume of run-off. Impacts on fish populations and nature conservation in general are addressed in Chapter 10 Ecology, and are not considered in detail within this chapter.

15.7 Mitigation Measures

Track and Station Area Drainage Proposals As described in Section 15.5 the proposals include the provision of track and station drainage to a standard agreed with SEPA and in accordance with all relevant guidelines and requirements (see Section 15.5). SEPA request that surface water drainage is treated in accordance with the principles of Planning Advice Note 61 and “Sustainable Urban Drainage Systems Design Manual for Scotland and Northern Ireland”, CIRIA C521. This would include run-off from access roads, car parks, construction works, roofs, areas of hardstanding and point source discharges from stations and along the length of the track. It should be noted that The Water Environment (Controlled Activities) Regulations 2005 (CAR) came into force on 1 April 2006 and require authorisation of engineering works in, or in the vicinity of, inland waters or wetlands and having or likely to have a significant adverse impact on the water environment. The use of SUDS technology is a statutory requirement under CAR. SEPA advises that surface water drainage arrangements will need to meet the requirements of SEPA area staff, Scottish Water and the appropriate roads authority (Highways Agency / Local Authority). As drainage systems based on SUDS principles will have implications for site layout, SEPA recommend that there is general agreement on the scheme before parliamentary approval is given. SUD systems may be susceptible to damage because of mud and silt generated during site preparation and construction activity. Work must therefore be phased to ensure minimum risk and temporary silt traps or silt lagoons should be provided where necessary. As well as providing water quality attenuation and treatment and not adversely impacting upon the hydrological characteristics of any receiving watercourse, it is important that any SUD system is designed as a habitat enhancing landscape feature to maximise the wildlife value. Guidance on good practice can be obtained from SEPA’s publication ‘Ponds, Pools and Lochans’ (ISBN 1- 901322-16-5). SUDS design should ensure that the disposal of surface water does not result in the mobilisation into controlled waters of contaminants present in some of the proposed



station parking areas. Additionally any piped drainage systems on site must be designed to ensure that contaminant pathways are not created. Operational Impact Mitigation Compliance with SEPA pollution prevention advice will mitigate the majority of the potential impacts identified during the operation of the railway (impacts on flow characteristics, diffuse pollution from track bed run off and station/ car park areas etc). Culvert sizing and design will be such that impacts on flow characteristics and the movement of fish are avoided (see Chapter 10 for mitigation of ecological impacts). All trains using this railway will have enclosed systems for sewage from train toilets (Controlled Emission Toilets). These will be discharged to a central waste collection point, where disposal will take place in compliance with the appropriate SEPA consents. In addition, only electric rolling stock will operate on the Airdrie to Bathgate section. Electric multiple unit trains emit less pollutants onto the track than their diesel equivalents. The written approval of SEPA must be sought for the use of herbicides in or near rivers, and the user must ensure that the interests of other river users are not adversely affected (SEPA Guidance PPG5). Network Rail’s policy on Management of Lineside Vegetation (Network Rail Document RT/CE/C/008/255C, Sections 255 - 257 - Management of Lineside Vegetation) will be complied with. This includes mechanical and chemical methods, and includes a requirement for the process to be undertaken in compliance with a Management Plan developed for the route. The need for SEPA approval for herbicide application is noted. Application of herbicides shall be confined to the areas specified and spillage or spray drift of the material onto any watercourse shall be prevented. Herbicides shall not be applied in wet or windy conditions, nor stored, mixed or used in the vicinity on any watercourse or other body of water. Potential impacts arising from ongoing maintenance operations, e.g. to bridges, culverts and areas of track adjacent to watercourses should be mitigated by compliance with Pollution Prevention Guideline PPG 23 Maintenance of Structures Over Water. This covers measures to avoid pollution of water courses with substances such as metal particulates, paint and cement, and offers guidance on materials and techniques, containment and waste management. Water Quality Monitoring A programme of monitoring for high sensitivity watercourses should be produced in order to ensure effective protection before, during and after construction. Monitoring is likely to be a condition of any CAR licence. Construction Phase Mitigation Measures In order to mitigate potential impacts during the construction phase, civil engineering works must be carried out with due regard to the SEPA’s guidelines for water pollution prevention from civil engineering contracts: PPG5 Works In, Near or Liable to Affect Watercourses; and PPG6 Working at Construction and Demolition Sites. PPG5 sets out precautionary measures to avoid pollution of watercourses by typical construction pollutants such as silt, cement, concrete, oils and chemicals. PPG6 addresses the avoidance of pollution for specific construction issues such as site drainage, deliveries, storage and waste management. Contractors will be required to comply with Network Rail’s Code of Construction Practice. This provides detailed requirements addressing all aspects of construction



impacts, and includes specific measures to avoid/ reduce impacts on water resources and drainage. Recent pollution events at Hillend Reservoir and Lilly Loch suggest a need to consider special measures to ensure any containment features have adequate capacity to accommodate storm events and snow melt. Special measures will be required to avoid impacts on Hillend Reservoir during land reclamation works and the construction of the casting jetties. This is likely to include coffin dams, or similar measures. The detail of these measures should be agreed with SEPA, and contact with SEPA’s River Restoration Centre is recommended. Care will also be required to avoid inadvertent damage to unrecorded sewer tails. In the event of these being revealed in the course of the works, they will be picked up and arrangements made for connection to the sewer system. Measures will be taken to avoid the land reclamation works affecting the Eastercroft outfall to Hillend Reservoir. Care will be taken at all times to avoid physical damage to surface watercourses/ waterbodies and their banks. Mitigation Measures for Groundwater The groundwater is of poor quality therefore all large quantities of groundwater encountered during any site dewatering operations should be contained and controlled. This is required to prevent potential contamination of local surface watercourses that support aquatic life and are also possibly used for recreational or industrial use. If excess groundwater is required to be disposed of off site, then the relevant authorities should be contacted in order to provide the appropriate chemical data to allow categorisation and disposable of the material to take place within the current legislation. It is not proposed at this stage that additional contingency costs for disposal of Hazardous Waste are necessary. However contingency costs should be allowed for additional targeted investigation which may be required to determine the likelihood of ‘hotspots’ in the vicinity of the proposed new railway stations along the route, and/or to further classify waste materials in light of forthcoming changes in waste management regulation. At detailed design stage, mitigation of the effects on groundwater in the bedrock in areas known to be contaminated should be considered on a site-by-site basis, taking into account site investigation outcome, risk assessment and the hydrological regime. SEPA will require detailed proposals of how any significant effects will be reduced and in particular preventing discharge of List 1 substances to groundwater and preventing pollution of groundwater from List II substances. Mitigation measures to address soil contamination issues are detailed in Chapter 7. These will include capping or covering as appropriate to avoid seepage of leachate into ground or surface waters. Some of the mine seams and mine entries within the route corridor will potentially require treatment to minimise the likelihood of surface instability along the length of the track. This may take the form of consolidation of the workings by drilling infill holes through which grout can be pumped. Groundwater wells have been installed within boreholes that encountered potential mine workings at shallow depths, and will be monitored for a year, as requested by The Coal Authority. This will provide data on the peaks and troughs in flow rates and levels of the groundwater regime within the workings, and consideration will then be



given to appropriate modification of stabilisation treatment to avoid or minimise impacts on groundwater flow. Once the location of mineworkings requiring grouting is identified, SEPA will require full hydrogeological surveys of these areas to investigate whether the grouting process will alter the current flow of groundwater, thereby potentially adversely affecting watercourses in the area. SEPA will also need confirmation that the grouting of the mineworkings will not pollute groundwater or migrate to pollute surface waters. SEPA should be consulted on the treatment design prior to its implementation. Flood Risk Mitigation SEPA recommends that contact is made with Local Authorities’ Flooding Officer or Roads Department regarding flood risk in built up areas. SEPA is of the opinion that further information is required to determine the degree of flood risk and scoping/ mitigation, in the form of a Flood Risk Assessment (FRA). Flood risk assessment would be seen as essential at those sites listed as being at risk of flooding. The new generation flood mapping to be published later in 2006 should be referred to. Existing culverts have generally been retained, except where their capacity is grossly inadequate. This policy should ensure that the existing flood frequency and watercourse regime will be retained. SEPA advises that SPP7 indicates a more stringent standard of flood protection is appropriate for the majority of development. Compensatory flood storage may be required if the detailed proposals for the scheme increase the footprint of existing embankments. The integrity of Hillend Reservoir and the new embankments should be documented, and the potential for overtopping, wave action, scour and loss of stability of the reservoir retaining walls under normal operations and during both low flow and flood conditions should be considered. Scour protection may be required.

15.8 Assessment of Surface Water Quality Impacts 15.8.1 General

Potential sources of surface water quality impacts arising from the proposed development comprise contamination from run-off and spillages at track and station areas during construction, operation and maintenance phases. Operational impacts on water quality are not envisaged from the section of the track currently operational, as an increase in locomotive frequency is unlikely to significantly alter pollution concentration or risk. Construction phase impacts are likely to be greater for the section between Airdrie and Bathgate, as this section is no longer operational, and major works will be required to bring the track and structures up to an acceptable standard. This includes land reclamation works at Hillend Reservoir. The section of operational track between Bathgate and Edinburgh will only require minor works. Impacts from works in this section are generally of a low magnitude, therefore a less detailed impact assessment has been undertaken on this eastern section (See Section 15.2 Methodology). The risk of construction phase spillages and contamination by sediments, contaminated soil or construction materials will be greatly reduced by compliance with SEPA Pollution Prevention Guidelines and other mitigation as described in Section 15.7. Track run-off is not expected to be a significant source of contamination. Trains will be electric on the Airdrie to Bathgate stretch, so diesel/ diesel combustion products



will not be a pollutant in this location. Small volumes of lubricating oils and transmission fluids and brake linings will comprise the main pollutants from the trains themselves. These will be deposited on the track bed and will be washed by rainfall into the track ballast. This will retain many of the pollutants present, with the remainder feeding to french drains allowing percolation to the ground. This filtering action will remove many of the pollutants and thus the resulting effluent is unlikely to represent a significant pollution risk by the time it reaches the nearest watercourse or waterbody. A risk assessment undertaken by the Babtie Group concluded that there was no evidence of existing lateral seepage of leachate affecting nearby surface waters or surrounding vegetation, and that the likelihood of a future occurrence was low. Surface water run-off from trackside areas has the potential to be contaminated with herbicides. However, mitigation measures as detailed in 15.7 should reduce levels present to negligible. Any new station car parks and associated roadways will incorporate SUDS features, which include a level of water treatment through filtration and settlement. This will greatly reduce the concentration of any contaminants entering water courses from these sources. Oil interceptors will be proposed for station areas where oily substances may build up on surfaces. During culvert/ bridge construction/ maintenance operations, there is potential for direct spillages of paint etc into watercourses. However, the requirement to comply with SEPA guidance as set out in Section 15.7 will reduce this risk. It is assumed that all large quantities of groundwater encountered during any site dewatering operations will be contained and controlled, in order to prevent potential contamination of local surface watercourses. Note that the Water Environment (Controlled Activities) Regulations 2005, or ‘CAR Regulations’ come into force on 1 April 2006. Section 15.1.3 provides information on the implications of these Regulations.

15.8.2 North Calder Water

This watercourse is crossed three times by the railway, and is also fed by some tributaries and drains crossed by the railway. A new road bridge crossing the North Calder Water is proposed to allow access to Caldercruix West Station. A stretch of the North Calder Water runs within 20m to the north of the railway before feeding into the Hillend Reservoir. The remainder of the watercourse within the study corridor is downstream of the reservoir. The railway drainage system outfalls to the North Calder Water at several points. Construction Impacts Potential impacts from track laying and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. The new station proposed for Caldercruix includes a car park partly sited on the paper mill settlement lagoons. Not only are the lagoons thought to be in hydrological continuity with the North Calder Water, but they are also polluted with materials from the paper making process. Pollution Prevention Guidelines must be followed to reduce the risk of water quality impacts arising from works. The railway crosses the North Calder Water or its tributaries at several points, and there is a new road bridge crossing the watercourse proposed to allow access to Caldercruix Station. Track construction works and culvert and bridge repair/



construction works have the potential to directly impact on water quality in these locations. In addition, construction compounds are proposed close to or adjacent to the North Calder Water at Plains and Caldercruix. Works to structures comprise:

• Reconstruction of headwalls at culverts 1 and 2 (chainages 1300 and 1427)

• New replacement culverts 2A and 2B (chainages 3532 and 3800)

• Ford Bridge to the east of Plains (UB10) - This is single span underbridge, which carries the solum over the North

Calder Water, will be replaced

• Underbridge UB7 (west of settlement ponds at Caldercruix) - This single span underbridge carries the solum over North Calder Water. The

arch will be replaced

• New road bridge over the North Calder Water, linking A89 with Caldercruix Station car park

• Underbridge UB5: B825 to Limerigg (Hillend) - This bridge is a three-span viaduct underbridge, which carries the solum over

a road, a footpath and the North Calder Water. It will be retained, with possible modifications

• Underbridge 4 at Auchengrey. This structure will be replaced.

Cut and fill operations are proposed along the length of the route. The North Calder Water has been assessed as being a more sensitive receptor upstream of Hillend Reservoir as it can influence the water quality of the reservoir at this point. There is only a short section of the proposed works (approximate chainages 8300 to 8900) within 250m of this stretch of the watercourse. Major works within this stretch include the replacement of underbridge UB4 at Auchengrey (the entrance to the fishery). This bridge is located at the point that the North Calder Water meets the Hillend Reservoir. Construction impacts on water quality at this location are therefore assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track and structure

construction, spillages Receptor North Calder Water u/s of Hillend Reservoir. Major

sensitivity Magnitude Minor Character Medium probability, adverse, moderate scale, short-term Impact Significance Moderate Downstream of the reservoir, construction phase impacts on North Calder Water are assessed as: Sources Creation of construction compound. Storage of materials.

Sediments, construction materials, contaminated soil. Pathways Physical disturbance to create construction compound.

Surface water run-off from compound, station, track and structure construction, spillages

Receptor North Calder Water d/s of Hillend Reservoir. Moderate sensitivity

Magnitude Low - Medium Character Medium probability, adverse, moderate scale, short-term Impact Significance Minor-Moderate Operational Impacts



Potential water quality impacts on the North Calder Water during railway operation include track contaminants in surface water run-off via outfalls and direct impacts from spillages/ pollution incidents during bridge/ structure maintenance. The new station at Caldercruix is over 100m from the North Calder Water, but the car park is only 50m from this watercourse and the car park access road crosses the river. The distance between the station and the watercourse, and the installation of oil interceptors, reduces the likelihood of water quality impacts from the deposition of fuels, oils, or other wastes onto the tracks at the station. SUDS within the access road and associated car parking area will reduce the likelihood of contaminated runoff reaching the North Calder Water. Outfalls from the railway drainage system to the North Calder Water are proposed at several points along the route. As mentioned above, the North Calder Water will be crossed by the new Caldercruix Station access road. It is also crossed by the railway at:

• Ford Bridge to the east of Plains (UB10)

• Bleachfield Cottages to west of settlement ponds at Caldercruix (UB7)

• B825 at Hillend (UB5) Maintenance of these structures will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. As stated in 15.8.1, track and station area drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to a low level. Although there are several drainage outfalls from the track and station areas discharging to the North Calder Water, the river has a mean flow of 0.35m

3s-1, providing considerable dilution of the

already low level of contaminants likely to be present in the discharge. Impacts on water quality are therefore of a negligible magnitude, with or without the new stations. The stretch of the North Calder Water downstream of the Hillend Reservoir is a moderately sensitive receptor. Operational impacts on this stretch of water are assessed as being of negligible magnitude and significance. The North Calder Water has been assessed as being a more sensitive receptor upstream of Hillend Reservoir compared with the downstream stretch, as it can influence the water quality of the reservoir at this point. There is only a short section of the proposed works (approximate chainages 8300 to 8900) within 250m of this stretch of the watercourse. There are no stations or sidings proposed for this section of the route. One outfall is proposed into a field drain some 300m upstream of the North Calder Water. Operational impacts on this section are assessed as being of negligible magnitude. Impacts on the North Calder Water during railway operation are therefore assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track & station areas,

spillages Receptor North Calder Water. Major/ moderate sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.3 Mill Lade



The Mill Lade flows out of Hillend Reservoir, passes under the B825 and the railway at Underbridge 5 then flows towards the west adjacent to the A89, terminating just past the junction of the A89 with Caldercruix Main Street. The Mill Lade passes within 250m of the proposed railway between approximate chainages 5000 and 5750. Track drainage from both the existing and proposed track outfalls to the Mill Lade. The Mill Lade is considered to be of minor sensitivity. Construction Impacts The Mill Lade runs close to and is crossed by the proposed railway alignment at Underbridge UB5, and a section of the track drainage discharges to this watercourse. This creates the potential for adverse impacts on water quality arising from construction operations. Potential impacts from track laying and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. Underbridge UB5 is a three-span viaduct underbridge which carries the solum over the B825 to Limerigg (Hillend), the Mill Lade and the North Calder Water. It is generally in good condition, and will be retained subject to assessment. Excavations are proposed for track bed realignment in the stretch of the railway closest to the Mill Lade. Assuming all mitigation measures as stated in 15.7 are implemented, construction impact magnitude will be minor. The Mill Lade is a receptor of minor sensitivity. Construction phase impacts on the Mill Lade are therefore assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track construction, spillages Receptor Mill Lade. Minor sensitivity Magnitude Minor Character Low-medium probability, adverse, moderate scale,

short-term Impact Significance Minor Operational Impacts Potential water quality impacts on the Mill Lade during railway operation include track contaminants in surface water run-off via outfalls and direct impacts from spillages/ pollution incidents during maintenance of Underbridge 5 (UB5). An outfall from the railway drainage system to the Mill Lade is proposed at UB5. Maintenance of UB5 will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. As stated in 15.8.1, track drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to a low level. The outfall to the Mill Lade is unlikely to result in significant levels of contaminants reaching the Mill Lade. Impacts on water quality are therefore of a negligible magnitude. Impacts on water quality arising from the operation of the scheme are assessed as:



Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages Receptor Mill Lade. Minor sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.4 Lilly Burn/ School Burn

This burn forms the outflow from Lilly Loch, passing under the A89 and then the railway via culvert 5 in a south to north direction before entering the Hillend Reservoir. The Lilly Burn is a receptor of major sensitivity as this watercourse is reputed to be a spawning stream for trout. Construction Impacts The railway crosses the Lilly Burn just before it flows into Hillend Reservoir. There is thus only a section of a few metres of this watercourse at risk from the proposed scheme. The Lilly Burn/ School Burn passes under the proposed railway alignment via Culvert 5. Culvert 5 is a single span culvert, and was found to be in good condition and flowing well (Babtie culvert study, Appendix 6). Repairs will be required to bring the parapet up to standard. A new culvert will be constructed at chainage 6644 (culvert 4A). Excavations are proposed for track bed realignment in the stretch of the railway closest to the Lilly Burn. In addition, land reclamation works are proposed in Hillend Reservoir at this location. These works create the potential for adverse impacts on water quality arising from construction operations. Potential impacts from culvert repair/ installation, track laying, land reclamation and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. It is noted that these works will also affect the reservoir and are also considered within the section describing Hillend Reservoir impacts Assuming all mitigation measures as stated in 15.7 are implemented, construction impact magnitude will be minor, but this watercourse is sensitive to impacts owing to its trout spawning function. Construction phase impacts on the Lilly/ School Burn are assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track and structure

construction, reclamation works, spillages Receptor Lilly/ School Burn. Major sensitivity Magnitude Low Character Low probability, adverse, Minor scale, short-term Impact Significance Minor Operational Impacts Potential water quality impacts on the Lilly Burn during railway operation include track contaminants in surface water run-off via outfalls and direct impacts from spillages/ pollution incidents during maintenance of new culvert 4A and culvert 5.



Outfalls from the railway drainage system to the Lilly Burn are proposed at Culvert 5, just prior to the burn entering Hillend Reservoir. Maintenance of Culverts 4A and 5 will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. As stated in 15.8.1, track area drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to a low level. As the proposed outfall to the Lilly Burn is only a few metres from the end of this watercourse, impacts on water quality are likely to be of a negligible magnitude. All new culverts will be designed to allow the passage of migratory fish. The Lilly Burn is reported to be a trout spawning stream, and feeds into Hillend Reservoir, and is thus a major sensitivity receptor. Operational impacts on the Lilly Burn are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages Receptor Lilly Burn. Major sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.5 Bracco Burn

This burn passes under the A89 and then the railway via culvert 6 in a south to north direction before entering the Hillend Reservoir. Existing and proposed track drainage discharges to this culvert. The Bracco Burn is reported to be a trout spawning stream, and feeds into Hillend Reservoir, and is thus a major sensitivity receptor. Construction Impacts The Bracco Burn passes under the proposed railway alignment via Culvert 6. This creates the potential for adverse impacts on water quality arising from construction operations. Culvert 6 is a stone parapet found to be in good condition and flowing well (Babtie culvert study, Appendix 6). Proposed repair works are limited to minor repairs and construction of a parapet. The risk of impacts from track laying and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. Vertical realignment is not proposed for the track bed closest to the Bracco Burn, but excavations are proposed for the section approximately 100m to the west. The railway crosses the Bracco Burn just before it flows into Hillend Reservoir. There is thus only a section of a few metres of this watercourse at risk from the proposed scheme. Assuming all mitigation measures as stated in 15.7 are implemented, construction impact magnitude will be minor. Construction phase impacts on the Bracco Burn are assessed as:



Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track and structure works,

spillages Receptor Bracco Burn. Major sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor

Operational Impacts Potential water quality impacts on the Bracco Burn during railway operation include track contaminants in surface water run-off via the outfall to the culvert and impacts from spillages/ pollution incidents during maintenance of Culvert 6. Maintenance of Culvert 6 will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. As stated in 15.8.1, track area drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to a low level. The railway crosses the Bracco Burn just before it flows into Hillend Reservoir. There is thus only a section of a few metres of this watercourse at risk from the proposed scheme. Impacts on water quality are therefore of a negligible magnitude. Operational impacts on the Bracco Burn are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track areas, spillages Receptor Bracco Burn. Major sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.6 Barbauchlaw Burn

This watercourse is crossed by the railway at underbridge UB3 just to the west of the Standhill Farm road, and passes to the south of Blackridge in parallel to the railway before turning northeast under the A89 and out of the study area. It flows within 250m of the proposed railway for some 2 km, and appears to receive the flow from culvert 15 (chainage 14158). The Barbauchlaw Burn is a designated Scottish Wildlife Trust site some 450m downstream of the study corridor and is thus considered a moderately sensitive receptor. Construction Impacts The Barbauchlaw Burn passes under the proposed railway alignment via underbridge UB3. UB3 is a single span underbridge assessed as being in generally good condition (Babtie Structures Report 2004). This structure will require to be rebuilt to meet vertical alignment requirements. In addition, the bridge taking Harthill Road (B718) over the railway will be replaced. This structure is within 100m of the burn. This creates the potential for adverse impacts on water quality arising from construction operations. Culvert 15 is a masonry culvert in poor condition, which requires a new manhole upstream and a new headwall downstream. The outlet from the culvert drains across a field towards the Barbauchlaw Burn (approximately 100m to the north). Sediments



and other polluting materials which may enter the culvert flow during construction works are likely to settle out before reaching the Barbauchlaw Burn, so works on this culvert are unlikely to affect the Barbauchlaw Burn. Vertical realignment is proposed for the track bed within the vicinity of the Barbauchlaw Burn. This will comprise both cut and fill operations. A construction compound will be located adjacent to the burn. A further compound is to be located at Standhill Farm – this location is marshy in places and may be in continuity with the Barbauchlaw burn or the Black Moss Burn. The risk of impacts from track laying and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. Assuming all mitigation measures as stated in 15.7 are implemented, construction impact magnitude will be minor. Construction phase impacts on the Barbauchlaw Burn are assessed as: Sources Creation of construction compounds. Storage of

materials. Bridge and culvert construction. Sediments, construction materials, contaminated soil.

Pathways Physical disturbance. Surface water run-off from compound & track, spillages. Mobilisation of sediments

Receptor Barbauchlaw Burn. Moderate sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor Operational Impacts Potential water quality impacts on the Barbauchlaw Burn during railway operation include track contaminants in surface water run-off via outfalls and direct impacts from spillages/ pollution incidents during maintenance of Underbridge UB3 and culvert 15. Outfalls from the railway drainage system to the Barbauchlaw Burn are proposed at various points near Blackridge. Maintenance of Underbridge UB3 and culvert 15 will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. The outlet from culvert 15 drains across a field towards the Barbauchlaw Burn (approximately 100m to the north). Pollutants entering the culvert during maintenance are likely to settle out before reaching the Barbauchlaw Burn. As stated in 15.8.1, track drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to low/ negligible. Operational impacts on the Barbauchlaw Burn are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Barbauchlaw Burn. Moderate sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible



15.8.7 Black Moss Burn

This burn flows in parallel and to the south of the railway before passing under it twice via culverts 16 (chainage 16145) and 17 (chainage 16412). 36m of new culvert (15A) will be constructed near chainage 15500 to allow the passage of water to the Black Moss Burn. The Black Moss Burn is a receptor of minor sensitivity. Construction Impacts The Black Moss Burn passes under the proposed railway alignment via culverts 16 and 17. This creates the potential for adverse impacts on water quality arising from construction operations. Culvert 16 is a corrugated steel pipe in poor condition requiring a new headwall on both sides. Culvert 17 is in good condition with no works required. Vertical realignment is proposed for the track bed within the vicinity of the Black Moss Burn. This will comprise fill operations. A construction compound will be built a near Standhill Farm at Blackridge. This area is marshy in places and may flow to the Black Moss Burn. The risk of impacts from track laying and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. Assuming all mitigation measures as stated in 15.7 are implemented, construction impact magnitude will be minor. Construction phase impacts on the Black Moss Burn are assessed as: Sources Creation of construction compound. Storage of

materials. Sediments, construction materials, contaminated soil.

Pathways Physical disturbance to create construction compound. Surface water run-off from compound & track, spillages

Receptor Black Moss Burn. Minor sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor

Operational Impacts Potential water quality impacts on the Black Moss Burn during railway operation include track contaminants in surface water run-off via outfalls and direct impacts from spillages/ pollution incidents during maintenance of culverts 16 and 17. Outfalls from the railway drainage system to the Black Moss Burn are proposed at culverts 16 and 17. Maintenance of culverts 16 and 17 will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. As stated in 15.8.1, track drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to a low level. Operational impacts on the Black Moss Burn are assessed as:



Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Black Moss Burn. Minor sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.8 Bog Burn The Bog Burn flows northwards through the Bog Burn Flood Lagoons in the south of Bathgate. It is culverted under the railway at Starlaw and again at the Boghead Bridge (underbridge UB 1A), where it becomes known as the Bathgate Water. The Bog Burn is considered to be a receptor of minor sensitivity

Construction Impacts

The Bog Burn is culverted under the operational section of the railway near the Starlaw overbridge. It is proposed to extend this culvert or redirect the watercourse to allow creation of a new site for the STVA car distribution depot. The relocation of Bathgate Station includes construction of a train cleaning yard on what is presently the STVA car depot. SEPA advises that it has serious concerns over the potential culverting of the Bog Burn, and considers culverting to be the design of last resort for crossing watercourses. SEPA advise that if culverting is to be undertaken at this location (greenfield riverside land), this activity would need to be licensed A under CAR, with full justification of the need for the culvert. Only minor works are proposed for the Starlaw overbridge, and proposed works to the track within the vicinity of Starlaw are limited to upgrading of existing operational railway to take an electrified double track. The culvert is of recent construction and is unlikely to require work. The burn also passes under the solum at the Boghead Bridge. This structure is generally in good condition, and will be retained subject to assessment. Vertical realignment is proposed for the reinstatement of the railway within the vicinity of the Bog Burn. This will comprise cut operations. Track laying and associated earthworks will be reduced by compliance with SEPA Pollution Prevention Guidelines. These works create the potential for adverse impacts on water quality arising from construction operations. However, this watercourse is of existing poor quality, and the majority of the proposed works are downstream of the SWT wildlife site, with only minor works proposed upstream more than 1km from the SWT site. Assuming all mitigation measures as stated in 15.7 are implemented, impact magnitude will be minor. Construction phase impacts on the Bog Burn are assessed as:



Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Bog Burn. Minor sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor Operational Impacts

Potential water quality impacts on the Bog Burn during railway operation include track contaminants in surface water run-off via outfalls and direct impacts from spillages/ pollution incidents during maintenance of the Boghead Bridge or culvert at Starlaw. Operational impacts from the section at Starlaw will be of negligible significance, as they will not materially change from those at present, as this section currently operates as a railway. Outfalls from the railway drainage system to the Bog Burn are proposed at the Boghead Bridge. Maintenance of this structure will be required, but this is likely to be infrequent and of a minor nature, with little risk to water quality. As stated in 15.8.1, track drainage arrangements and compliance with the mitigation measures set out in 15.7 will reduce the potential concentration of contaminants within surface water drainage to a low level. This watercourse is of existing poor quality. It passes under the new section of railway downstream of the SWT wildlife site, and thus significant impacts on water quality are not envisaged. Operational impacts on the Bog Burn are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Bog Burn. Minor sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.9 Boghead Burn

The Boghead Burn flows within 50m of the railway as it approaches Bathgate, but does not flow under the route. Provided mitigation measures as stated in 15.7 are implemented, water quality impacts on this watercourse during operation or construction will be negligible or non-existent.

15.8.10 Lochshot Burn Tributary This small burn is culverted under the operational railway at the east end of Tailend Moss nature reserve. There are no known works proposed for this culvert. Works to the track comprise upgrading to electrified double track. Lochshot Burn tributary is considered to be of minor sensitivity. Construction phase impacts on the Lochshot Burn tributary are assessed as:



Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Lochshot Burn tributary. Minor sensitivity Magnitude Minor Character Low probability, adverse, minor scale, short-term Impact Significance Minor Operational impacts on this watercourse will not be significantly different to those at present and adverse impacts are therefore considered negligible.

15.8.11 Deans Burn This watercourse passes under the operational railway via an underbridge south of Deans, at Eliburn, Livingston. There are no known works proposed for this structure. Works to the track in the vicinity of the Deans Burn are limited to upgrading works for electrification. The Deans Burn is considered to be of minor sensitivity. Construction phase impacts are assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Deans Burn. Minor sensitivity Magnitude Minor Character Low probability, adverse, minor scale, short-term Impact Significance Minor Operational impacts on this watercourse will not be significantly different to those at present and adverse impacts are therefore considered negligible.

15.8.12 Beugh Burn This watercourse is culverted under the operational railway at the A899 junction with the M8. Only minor works are proposed to the bridge structure. Works to the track in the vicinity of the Beugh Burn are limited to upgrading works for electrification. The Beugh Burn is considered to be of minor sensitivity. Construction phase impacts are assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Beugh Burn. Minor sensitivity Magnitude Minor Character Low probability, adverse, minor scale, short-term Impact Significance Minor Operational impacts on this watercourse will not be significantly different to those at present and adverse impacts are therefore considered negligible.

15.8.13 Un-named burns and ditches

Construction Impacts Minor watercourses and ditches passing under or close to the proposed works will be at risk from spillage of construction materials and physical damage. The proposed works compounds in several locations are located close to or on top of ditches/ minor watercourses.



The risk of adverse impacts will be reduced by the implementation of measures set out in section 15.7. Construction phase impacts on these various burns and ditches is therefore assessed as:

Sources Construction compound. Storage of materials.

Sediments, construction materials, contaminated soil Pathways Physical disturbance to create construction compound.

Surface water run-off from compound & track, spillages

Receptor Un-named burns and ditches. Minor sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor

Operational Impacts There are numerous minor burns and drainage ditches crossing the proposed route. There is potential for these minor watercourses to receive surface water run-off from the track and station areas, and also spillages of maintenance material.

However, the implementation of the measures described in 15.7 will reduce the likelihood of an adverse impact. These minor watercourses are considered to be of minor sensitivity. Operational impacts on them are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Un-named burns and ditches. Minor sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.14 Hillend Reservoir

The proposed route runs along the southern banks of this large waterbody for some 3 km. The proposed cyclepath and angling club access road will require land reclamation works at Hillend Reservoir. These works will comprise, in outline:

• car access to the Angling Club via the underbridge 240/056

• 5.5m wide carriageway with 3m verges

• suitable for cars, pedestrians and cyclists but not HGVs or coaches

• retaining feature 4.3m high and 160m long approximately

• the retaining feature will extend a maximum of some 5m into the reservoir Casting jetties will require to be constructed into the reservoir in order to maintain a safe distance between anglers and the railway/ cyclepath. Works to the existing rock cuttings are proposed, including widening by up to 3m, and discharges to the reservoir are proposed at various points along the route. In addition, Hillend Reservoir is fed by a network of minor streams and burns, some of which pass under the existing railway solum. The southern boundary of the reservoir includes extensive areas of marshy land through which the railway will pass. This includes the Garrieston West SINC. There is therefore potential for impacts on the water quality of the reservoir through pollutants from the proposed works being conducted to the reservoir via these watercourses and marshlands.



Hillend Reservoir is of good quality and is a highly valued recreational resource. It is therefore considered to be a receptor of major sensitivity. It is assumed that the mitigation measures described in Section 15.7 will be implemented in order to reduce the risk of adverse impacts. On this basis, construction phase impacts are assessed as:

Sources Sediments, construction materials, contaminated soil Pathways Engineering works within the reservoir and on its

banks, surface water run-off from track construction, spillages, pollutants in feeder burns

Receptor Hillend Reservoir. Major sensitivity Magnitude Minor-moderate Character Medium probability, adverse, moderate scale, short-

term Impact Significance Moderate Operational impacts are assessed as: Sources Oils, herbicides, maintenance materials, land

reclamation Pathways Surface water run-off from track, spillages during

maintenance works, pollutants in feeder burns. Direct encroachment into reservoir

Receptor Hillend Reservoir. Major sensitivity Magnitude Minor Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.15 Lilly Loch

Lilly Loch is some 600m from the proposed railway alignment at its nearest point, and the proposed railway works are not within its catchment. Impacts on Lilly Loch are not envisaged during either operation or construction phases.

15.8.16 Blawhorn Moss Blawhorn Moss is 1km to the north of the proposed railway and the proposed railway works are not within its catchment. Impacts on Blawhorn Moss are not envisaged during either operation or construction phases.

15.8.17 Caldercruix Moss

The proposed railway is within 50m of this SINC, and as such there is potential for water quality impacts arising from spillages and runoff during construction and operation. However, there are no direct outfalls to Caldercruix Moss, as track drainage flows to the North Calder Water or the Mill Lade in this vicinity. It is considered to be a receptor of moderate sensitivity. Construction phase impacts are assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Caldercruix Moss. Moderate sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor Operational phase impacts are assessed as:



Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Caldercruix Moss. Moderate sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.18 Forrestfield Moss The railway passes through this moss on the eastern boundary of Hillend Reservoir. It is proposed to locate a construction compound to the south of the track in this location. It will therefore be at risk from adverse impacts arising from spillages and run off during construction and operational phases. Outfalls to Forrestfield Moss are not proposed. Adverse impacts will be minimised by the implementation of the mitigation measures described in Section 15.7. Construction phase impacts are assessed as: Sources Creation of construction compound. Storage of

materials. Sediments, construction materials, contaminated soil.

Pathways Physical disturbance to create construction compound. Surface water run-off from track & compound, spillages

Receptor Forrestfield Moss. Moderate sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor Operational phase impacts on Forrestfield Moss are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Forrestfield Moss. Moderate sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.19 Raiziehill Moss

This SWT site straddles the proposed route near Blackridge. It will therefore be at risk from adverse impacts arising from spillages and run off during construction and operational phases. Outfalls to Raiziehill Moss are not proposed. Adverse impacts will be minimised by the implementation of the mitigation measures described in Section 15.7. Construction phase impacts are assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Raiziehill Moss. Moderate sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor



Operational phase impacts are assessed as: Sources Oils, herbicides, maintenance materials Pathways Surface water run-off from track, spillages during

maintenance works Receptor Raiziehill Moss. Moderate sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible

15.8.20 Tailend Moss

Tailend Moss is a SWT nature reserve located adjacent and to the south of the operational rail line between Bathgate and Livingston. Proposed works within the vicinity of Tailend Moss are limited to track upgrading for a double electrified track. Construction phase impacts are assessed as: Sources Sediments, construction materials, contaminated soil Pathways Surface water run-off from track, spillages Receptor Tailend Moss. Moderate sensitivity Magnitude Minor Character Low probability, adverse, moderate scale, short-term Impact Significance Minor Operational impacts on Tailend Moss will not be significantly different to those at present and adverse impacts are therefore considered negligible.

15.8.21 Other Waterbodies

Bogburn Flood Lagoons The proposed railway alignment is some 250m from the nearest boundary of the lagoons site, but may lie within its catchment in parts. Notwithstanding, the distance between the site and the works, and assuming mitigation as stated in Section 15.7 is implemented, adverse impacts will be negligible during either construction or operational phases. Caldercruix Mill Settlement Ponds Three of the five ponds will be infilled to create a car park for the new station at Caldercruix. The remaining two will be required temporarily during the construction phase. The ponds are accessed via underbridge UB6. UB6 will be retained but requires some repointing works. Though the ponds have nature conservation value (SINC), those to be lost to development are mostly dry and appear significantly contaminated. As a water resource therefore they are considered to be of only minor receptor sensitivity. Impact significance is considered minor. Millbank Quarry Ponds One pond lies some 20m to the south of the railway at Blackridge, with three much smaller ponds a further 200m to the south. Overbridge OB4 crosses the railway in the vicinity of the large pond. This bridge is to be replaced. Levels of contaminants reaching the quarry ponds during either construction or operational phases are likely to be low. . The ponds are considered to be of only minor receptor sensitivity. Impact significance is considered minor.



15.9 Flooding The proposals are to reinstate a railway largely on an existing solum. Although some realignment is proposed, this is minimal and will not significantly affect the movement of water across the railway corridor. A Drainage Study was undertaken by Jacobs Babtie to indicate flows in watercourses crossing the route, and outfall flows from the longitudinal drains. New culverts will be constructed where existing culverts were found to have insufficient capacity at a 1 in 20 year flood, or where an existing culvert could not be positively identified. These new culverts have been designed to pass a 1 in 200 year flood without surcharge, and will meet requirements with regard to the passage of migratory fish. Land upstream of the culverts is generally unimproved grassland, and will not suffer any damage from infrequent flooding. The railway would generally be unaffected by such occurrences, since a flood surcharge would build up and greatly increase culvert capacity. Station areas and car parks will include SUDS measures, incorporating attenuation measures and oil interceptors, and are designed to avoid impacts on water quantity/ flow in receiving water courses. The design of the new track and station drainage measures will ensure that there are no significant changes to the hydrological characteristics of the area, although measures will be required to address drainage problems in the peat area to the west of Hillend Reservoir. SEPA has indicated a number of locations where flooding may be an issue at present. Detailed Flood Risk Assessment in specific locations will inform mitigation design to ensure existing flood risk is not increased by the proposals. During construction, culvert and bridge works may require temporary diversions of flow, but these will be of negligible magnitude and significance. Impacts on flooding are assessed as: Sources Temporary diversions, new culverts and drainage

system Pathways Altered flows Receptor Hydrological characteristics, flood risk. Moderate

sensitivity Magnitude Negligible Character Low probability, adverse, small scale, long-term Impact Significance Negligible Although the proposals are likely to have a negligible impact on existing flood risk, the acceptability of the existing flood risk will require consideration regarding engineering/ operational feasibility. This is outwith the remit of this Environmental Impact Assessment. It should be noted with regard to the drainage study findings, that in many cases, precise invert levels were not obtained at the existing culverts, so that capacities have been based on a typical 1 in 100 gradient. This is a critical assumption, and should be

15.10 Groundwater Impacts

Sources of groundwater impacts from the railway proposals are percolation of track/ station contaminants and spillages and volume impacts from altered land drainage.



Construction phase impacts on groundwater may arise if the works disturb contaminated land and mobilise pollutants, allowing them to enter groundwater. This is unlikely to occur as areas of contamination will be identified and treated appropriately in order that any contaminants are contained. Preliminary soil analyses show in general, low levels of contaminants (see Chapter 7 for detail on soil contamination). The fill material also appeared relatively consistent along the length of the route. Risks to human health and to the environment are considered low. Some contamination of groundwater within the railway corridor is known to be present (see Table 15.5). Another source of groundwater contamination during the construction phase is accidental spillage of construction materials. This risk will be minimised by compliance with SEPA guidelines as set out in Section 15.7. Discussions between the Babtie Group and The Coal Authority brought to light concerns about ground water flow within the mine workings. Some of the many seams and mine entries present within the route will potentially require treatment to minimise the likelihood of surface instability along the length of the track. This may take the form of consolidation of the workings by drilling infill holes through which grout can be pumped. Grout pumped into worked seams may inhibit the existing groundwater flow regime present. Consideration will be given to appropriate modifications to the proposed stabilisation/ consolidation treatment following analysis of data collected from groundwater wells installed within boreholes. Construction phase impacts on groundwater are assessed as: Sources Soil contamination, spillages, grouting Pathways Pollutant mobilisation during earthworks, percolation,

flow impedence Receptor Groundwater quality & flow. Moderate sensitivity Magnitude Low Character Low probability, adverse, small scale, long-term Impact Significance Low

During railway operation, the level of contaminants reaching groundwater is likely to be very low, owing to the geology of the area, the drainage measures in force and the low levels of pollutants already present in the soil and produced by railway operation. A risk assessment conducted by Jacobs Babtie concluded that there was no evidence of downward seepage of leachate into groundwater, and that the likelihood of an occurrence was very low. Due to the potential for contamination to be present within some of the proposed parking areas, the disposal of surface water to ground could result in the leaching of contaminants through soil and potentially entering groundwater. SUDS design will be required by SEPA to take this into account. Operational phase impacts on groundwater are assessed as: Sources Track drainage, soil contamination Pathways Percolation of surface water run-off Receptor Groundwater quality. Moderate sensitivity Magnitude Negligible Character Very low probability, adverse, small scale, long-term Impact Significance Negligible



15.11 Outline Assessment of Water Resource Impacts from Uphall Station to Edinburgh

15.11.1 Baseline

The principal watercourses in this area are the Union Canal and the River Almond. These are crossed by the railway at Muirend and Birdsmill House respectively. A few minor, un-named watercourses are also within the vicinity. Union Canal The Union Canal is a 50 km contour canal from Lochrin Basin in Edinburgh to Falkirk, where it meets the Forth and Clyde Canal. The canal was built between 1818 and 1822. It closed to commercial use in the 1930s and is now used recreationally by canoeists and rowers. The Edinburgh, Ratho and Linlithgow Canal Societies promote general use of the canal and hire rowing and narrow boats. The Millennium Link joined the Falkirk end of the canal to the Forth and Clyde Canal again in the year 2000 with the Falkirk Wheel. The other end, Lochrin Basin, is being redeveloped as Edinburgh Quay for commercial and residential use. 2004 data from SEPA show the Union Canal overall water quality classification to be B (fair) for a 9.37km stretch at Broxburn. This is the closest monitoring point to where the railway crosses the canal. The canal is considered to be of moderate sensitivity. River Almond The River Almond was one of the most polluted rivers in Scotland. To address this, an integrated management plan was launched in 1998 and water quality is improving. The river is 48 kilometres in length and has a catchment of 375 square kilometres; most of which is in West Lothian although its source is in North Lanarkshire and it enters the Firth of Forth SPA (Special Protection Area – a European nature conservation designation) at Cramond, in Edinburgh. 2004 data from SEPA show the River Almond overall water quality classification to be B (fair) for a 5.12 km stretch at Birds Mill. Birds Mill is the location of the railway crossing. The River Almond is considered to be of high sensitivity due to it flowing to an SPA.

Groundwater SEPA’s Groundwater Vulnerability Map shows the route to be mostly moderately permeable with low permeability drift deposits. In the absence of more detailed information on groundwater, the sensitivity is assumed to be moderate. Flooding This section of the railway is operational at present with no indication of flooding problems. The nature of the proposed works did not indicate the need for a detailed flood risk assessment.

15.11.2 Impact Assessment

The section of track between Uphall Station and Edinburgh requires only electrification and some bridge works. Construction phase impacts on water resources would only be likely where bridge works are close to a water course or water body. Electrification works are not envisaged to create any significant level of



disruption to water resources. Standard mitigation for construction works in the vicinity of watercourses will be required. A full list of bridge works is provided in Chapter 16. At Birdsmill Bridge, no major engineering works are proposed. However, as the bridge is so long, overhead electrical masts will be attached onto the bridge structure, probably through bolts. Structures will be attached to the outer face of the parapet and will require drilling and scaffolding and will require drilling and scaffolding. The significance of impacts on the River Almond is assessed as negligible. Works within the vicinity of the canal will consist only of electrification works. Impacts on water resources from electrification works are considered to be of negligible magnitude. The significance of impacts on the Union Canal is assessed as negligible. None of the bridges at which major works are proposed are close to watercourses or waterbodies. It is possible that minor drainage ditches or unnamed burns may be present in the vicinity of works. The potential of impacts on these will be reduced by the mitigation measures described in Section 15.7. These water features are considered to be of minor sensitivity, and overall impacts on surface water features in the Uphall to Edinburgh corridor are considered to be of negligible significance. The nature of the proposed works indicates that impacts on groundwater during construction will be of negligible magnitude. This stretch of track is fully operational at the moment, and therefore it is envisaged that the addition of approximately 72 electric train movements per day will have a negligible impact on flood risk, surface water or groundwater resources during the operational phase.

15.12 Conclusions

This assessment of impacts on water quality and drainage indicates no major impacts are likely on water resources. However, the railway’s proximity to such a large number of surface water features, and in particular the Hillend Reservoir, gives rise to some moderately significant impacts during the construction period. Careful implementation of all mitigation measures will be key to ensuring surface water quality impacts are kept to a minimum. The appropriate applications under the Controlled Activities Regulations will be required. No significant changes to the flood risk of the area are anticipated as the railway solum is already present, although engineering design will need to take account of existing flood risk. Significant impacts on groundwater quality or quantity are not expected. Table 15.6 overleaf summarises water and drainage impacts.



Table 15.6 Summary of Water and Drainage Impacts

Receptor Impact Significance Comment

Surface water quality Airdrie to Uphall

Construction Operation

• N Calder u/s H. Res

• N Calder d/s H. Res

• Mill Lade

• Lilly Burn

• Bracco Burn

• Barbauchlaw Burn

• Black Moss Burn

• Bog Burn

• Boghead Burn

• Lochshot Burn

• Deans Burn

• Beugh Burn

• Un-named burns

• Hillend Reservoir

• Lilly Loch

• Blawhorn Moss

• Caldercruix Moss

• Raiziehill Moss

• Tailend Moss

• Bogburn lagoons

• Mill ponds

• Quarry ponds

Moderate

Minor/moderate Minor Minor Minor Minor Minor Minor

Negligible Minor Minor Minor Minor

Moderate No impacts No impacts Minor Minor Minor

Negligible Minor Minor

Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible No impacts No impacts Negligible Negligible Negligible Negligible Minor Minor

Assumes full compliance with SEPA guidance and soil contamination mitigation measures.

Flooding Airdrie to Uphall

Negligible Negligible

Groundwater Airdrie to Uphall

Minor Negligible

Water resources East of Uphall

• River Almond

• Union Canal

• Groundwater

• Flooding

All Negligible All Negligible Assumes full compliance with SEPA guidance and soil contamination mitigation measures.

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