Description of main environmental impacts and proposed mitigation

Air quality

Impacts

  • TM implemented during the scheme may result in an increase in vehicle emissions through idling vehicles and increased congestion along the diversion route, should one be required. This may result in a temporary deterioration in local air quality. 
  • During construction activities, such as removal of old road surface, there is the potential for an increase in dust and emissions from plant and machinery. This is likely to cause a slight deterioration in air quality within the local area and cause a nuisance due to increased dust.
  • The impacts identified will be temporary for the duration of the works only and therefore no permanent change is predicted on air quality. 

Mitigation

    • All vehicles will switch off engines when stationary; there will be no idling vehicles.
    • Site layout will be planned (including plant, vehicles and Non-Road Mobile Machinery (NRMM)) so that machinery and dust causing activities are located away from receptors, as far as reasonably practicable.
    • All plant and fuel-requiring equipment utilised during construction will be well maintained in order to minimise emissions.
    • Planing operations will be wetted to reduce dust arising.
    • Drop heights to haulage vehicles will be minimised where practicable.
    • Lorries will be sheeted when carrying dry materials.
    • Surfaces will be swept where loose material remains following planing.
  • Green driving techniques will be adopted, and effective route preparation and planning undertaken prior to works.
  • Plant, vehicles and NRMM will be regularly maintained, paying attention to the integrity of exhaust systems to ensure such fuel operated equipment is not generating excessive fumes.

No significant effects are anticipated and therefore no further assessment in accordance with DMRB Guidance document LA 105: Air Quality is required.

Landscape and visual effects

Impacts

  • During night-time programming, misdirected site lighting could cause disturbance to any surrounding residential properties and core paths.
  • There will likely be a short-term impact on the landscape character and visual amenity of the site as a result of the presence of construction plant, vehicles, and TM.

Mitigation

  • Throughout all stages of the works, the site will be kept clean and tidy, with materials, equipment, plant and wastes appropriately stored, reducing the landscape and visual effects as much as possible. 
  • Plant, vehicles, and materials will be contained to hardstanding areas within the carriageway boundary (as far as reasonably practicable). Should damage to the landscape occur, reinstatement will be carried out. 
  • Any temporarily site lighting will be directional and pointed to the works only.

With mitigation measures and best practice in place, it is anticipated that any landscape and visual effects associated with the works will not be significant. Therefore, in accordance with DMRB Guidance document LA 107: Landscape and Visual Effects, no further assessment is required.

Biodiversity

Impacts

  • An increase in noise levels and misdirected site lighting has the potential to disturb any protected species nearby.
  • Works will be confined to the carriageway boundary, involving like-for-like carriageway resurfacing with no earthworks. As such, there is limited potential to spread or introduce INNS or target species.
  • The scheme has the potential to impact the Clyde Valley Woods SAC.

Mitigation

  • Vehicles and materials will not be stored or parked on grass verges where possible. Where damage occurs, the reinstatement of the grass verge will be carried out.
  • ‘Soft start’ techniques will be utilised with noise heavy equipment/plant/machinery in order to avoid disturbance to any potential noise sensitive species present in the area.
  • Due to night-time programming, where lighting is required, hoods will be used and lights directed at works and away from ecological receptors including any watercourses, to minimise disturbance to nocturnal species.
  • As part of the NMC contract, Amey, on behalf of transport Scotland, have been asked to keep a record of various target species, including rosebay willowherb and common ragwort. Works will not be carried out in the carriageway verge, if this is not possible and works are likely to result in the spread of this species through disturbance, the Amey landscaping team will be consulted.
  • Should a protected species been seen on site during construction, works will stop, and the ET&S Team be contacted.

A Habitats Regulations Appraisal (HRA) was undertaken and has concluded that there will be no Likely Significant Effects (LSE) on Clyde Valley Woods SAC due to:

  • No reduction in habitat area, with all works confined to the existing carriageway boundary.
  • No change in the level of disturbance to key species as a result of the works.
  • No increased habitat or species fragmentation.

With the above mitigation measures and best practice being adhered to, no significant effects on biodiversity are anticipated. Therefore, in accordance with DMRB Guidance document LA 108: Biodiversity, no further assessment is required.

Geology and soils

Impacts

  • The proposed construction activities will be confined to existing layers of the M74 carriageway, and as result, are not anticipated to cause any change to or have a negative impact on geology and soils.
  • As works will be confined to the boundary of the M74 carriageway, there will likely be no impacts to Cander Moss SSSI.

Mitigation

  • Where damage to soil occurs from vehicles stored and parked on the verge of the carriageway, the reinstatement of the grass verge will be carried out. Should damage occur, Amey’s Landscape Team will be contacted.
  • Spill kits will be present on site and all operatives will be fully trained in their use. Any fuels or chemicals required for use will be stored securely with drip trays used appropriately and stored under any chemical or fuel containers. 
  • If any unusual odours or soil colourations are identified during the works, the works will cease, and Amey’s Energy Transition & Sustainability Team will be notified.
  • Operatives will be briefed on Cander Moss SSSI located adjacent to the scheme extents and ensure there is no encroachment from the works.

With best practice mitigation measures in place, no significant effects associated with geology and soils. Therefore, in accordance with DMRB Guidance document LA 109: Geology and Soils, no further assessment is required. 

Material assets and waste

Impacts

  • Transportation and recovery of materials/waste will require energy deriving from fossil fuel, a non-renewable source.
  • The design life for the TS2010 surfacing proposed is estimated to be 20 years. This will reduce the requirement for maintenance to this section of road over the period.
  • The works will result in contribution to resource depletion through use of virgin materials.
  • There will be an increase in waste sent to landfill sites if waste materials are not recycled or reused.

Mitigation

  • Materials will be derived from recycled, secondary or re-used origin as far as practicable within the design specifications to reduce natural resource depletion and associated emissions.
  • Materials will be delivered on site when required.
  • The Contractor will comply with all ‘Duty of Care’ requirements, ensuring that any surplus materials or wastes are stored, transported, treated, used, and disposed of safely without endangering human health or harming the environment. All waste transfer notes and/or waste exemption certificates will also be completed and retained.
  • Uncontaminated road planings arising from the works will be fully recycled under a SEPA Paragraph 13(a) Waste exemption in accordance with guidance on the Production for Fully Recovered Asphalt Road Planings.
  • Use of TS2010 will reduce the usage of imported aggregates and increase the use of a wider range of sustainable aggregate sources thus reducing GHG emissions.
  • Where possible all materials will be reused throughout the network, if not possible they will be recycled locally at a suitably licenced waste management facility.
  • All special waste, such as tar, will be transport by suitable licenced contractor and be accompanied by correctly completed special waste consignment note (SWCN) providing information about the waste, the producer and the person the waste is being handed to; the SWCN will be kept for three years, the Site Responsible Manager is responsible for ensuring these are retained onsite.
  • All waste leaving the site will be removed from site by a licence waste carrier. All waste documentation will be provided when requested.

It has been determined that the proposed project will not have direct or indirect significant effects on the consumption of material assets or creation of waste. Therefore, in accordance with DMRB Guidance document LA 110: Material Assets and Waste, no further assessment is required.

Noise and vibration

Impacts

  • There will be an increase in noise and vibration levels, for properties within 300m, during construction due to the use of heavy plant and machinery, such as the roller, and an increase in HGVs.
  • TS2010 road surfacing is shown to have superior durability and noise reducing features compared to standard road surfacing mixes. Vehicle travellers and nearby receptors will benefit from the improved road surfacing as a result of the scheme.
  • The works are not likely to change the existing baseline noise level post construction for any sensitive receptors.

Mitigation

  • Site supervisor will monitor the effects of noise and vibration levels during the works and make necessary working arrangements.
  • On-site construction tasks will be programmed to be as efficient as possible, with a view to limiting noise disruption to local sensitive receptors. The noisiest works will be undertaken before 23:00 where possible.
  • Effects from noise will be kept to a minimum through the use of appropriate mufflers and silencers fitted to machinery. All exhaust silencers will be checked at regular intervals to ensure efficiency.
  • A ‘soft start’ to works will be in place, whereby plant/machinery/vehicles are started sequentially as opposed to simultaneously.
  • Due to nighttime programming, Amey’s Energy Transition & Sustainability Team has notified South Lanarkshire Council in advance of the works.
  • A letter drop will be delivered to residents within 300m to notify them of upcoming works, timings and duration.
  • Amey’s environmental briefing on Noise and Vibration will be delivered to site operatives prior to construction.

With best practice mitigation measures in place, and due to the works being of a minor, temporary, transient nature, no significant effects are predicted for noise and vibration. Therefore, in accordance with DMRB Guidance document LA 111: Noise and Vibration no further assessment is required.

Population and human health

Impacts

  • Access to residential properties will not be impacted by the works.
  • TM has potential to cause temporary levels of disruption to road users (i.e. congestion and increased travel times). There may be increased journey length should a diversion route be required.  
  • Land take is not required for this scheme therefore there will be no impact as a result of permanent or temporary land acquisition from private land, businesses, agriculture, Walkers, Cyclists or Horse riders (WCH) and/or community facilities as a result of the scheme.
  • Core paths and National Cycle Network Route 74 will not be impacted by the works as construction will be contained within the carriageway boundary.

Mitigation

  • TM restrictions/arrangements and any expected travel delays will be publicised within the local and wider area, in an effort to minimise disturbance to vehicular journey times.
  • Temporary site lighting will be directed at the scheme extents to avoid any misdirected lighting impacting properties with views of the works.

With best practice mitigation measures in place, no significant effects associated with Population and Human Health are predicted. Therefore, in accordance with DMRB Guidance document LA 112: Population and Human Health no further assessment is required.

Road drainage and the water environment

Impacts

  • If not adequately controlled, debris and run off from the works could be suspended in the surface water. In the event of a flooding incident or heavy rainfall, this debris may be mobilised and could enter the road drainage having a detrimental effect on the surrounding local water environment.
  • Potential for spills, leaks or seepage of fuels and oils associated with plant to escape and reach drainage systems and watercourses if not controlled, which may adversely impact the water environment.
  • Should flooding occur, this may delay the scheduled works.

Mitigation

  • All debris which has the potential to be suspended in surface water and wash into the local water environment will be cleaned from the site following the works.
  • Debris and dust generated as a result of the works will be prevented from entering the drainage system. This can be via the use of drain covers or similar.
  • Appropriate measures will be implemented onsite to prevent any potential pollution to the natural water environment (e.g., debris, dust, and hazardous substances). This will include spill kits being present onsite at all times, and the use of funnels and drip trays when transferring fuel etc.
  • The Amey control room will be contacted if any pollution incidences occur (available 24 hours, 7 days a week).
  • Visual pollution inspections of the working area will be conducted in frequency, especially during heavy rainfall and wind.
  • Weather reports will be monitored prior and during all construction activities. In the event of adverse weather/flooding events, all activities will temporarily stop, and only reconvene when deemed safe to do so, and run-off/drainage can be adequately controlled to prevent pollution.
  • Prior to works commencing, all operatives will be briefed on SEPA’s Guidance for Pollution Prevention (GPP) documents (particularly GPP 1, GPP 2, GPP 5, GPP 6, GPP 8, GPP 21 and GPP 22).

Providing all works operate in accordance with current best practice, as detailed within SEPA’s GPPs, the effects on Road Drainage and the Water Environment are considered not significant. Therefore, in accordance with DMRB Guidance document LA 113: Road drainage and the water environment no further assessment is required.

Climate

Impacts

  • GHG emissions will be emitted through the use of machinery, vehicles and materials used (containing recycled and virgin materials) and transporting to and from site.

Mitigation

  • Local suppliers will be used as far as reasonably practicable to reduce travel time and GHG emitted as part of the works.
  • Vehicles/plant will not be left on when not in use to minimise and prevent unnecessary emissions.
  • Further actions and considerations for this scheme are detailed in the above Material assets and waste section.

With best practice mitigation measures in place, the residual significance of effect on climate is considered to be neutral. Therefore, in accordance with DMRB Guidance document LA 114: Climate, no further assessment is required.

Vulnerability of the project to risks

As the works will be limited to the like-for-like resurfacing of the carriageway, there will be no change in vulnerability of the road to risk, or in severity of major accidents/disasters that would impact on the environment.

All mitigation measures will be adhered to onsite which considers the vulnerability of the project to be low.

Improvement of the road surface following carriageway resurfacing works will enhance skid resistance, and thus overall road safety on completion of the scheme.

It has been determined that the project is not expected to alter the vulnerability of the existing trunk road infrastructure to risk of major accidents or disasters.

Assessment cumulative effects

According to Amey’s Southwest Current Works Schedule, the following schemes are due to take place in the coming months:

However, no exact construction date for the above-mentioned schemes has been confirmed.

The Scottish Road Works Commissioner has not identified any works set to take place within the scheme extents within September 2025.

South Lanarkshire Council’s Planning Portal has not identified any works that are occurring within the scheme extents, within the proposed timeframe.

There may be an increase in traffic congestion and an increase in journey times due to TM set up for scheduled construction within the scheme extents.

Any schemes will be programmed to consider already programmed works, and as such any effect (such as from TM arrangements and potential construction noise) will be limited.

TM will be advertised in advance to road users to ensure any congestion is minimised. 

Overall, it is unlikely the proposed works will have a significant cumulative effect with any other proposed works in the local area. Considering the nature and scale of the maintenance works being undertaken, no in combination effects are anticipated.