Proposal for Northern Extension of Northolt Tunnel sift report
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- Bu səhifədəki naviqasiya:
- Location: Colne Valley OPTIONS CONSIDERED: Option A The Proposed Scheme as submitted in the hybrid Bill
- Above ground section between Northolt and Chiltern tunnels placed underground in bored tunnels with provision for connection spurs to Heathrow
- QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG
`Code 1 -
Accepted Uncontrolled when printed INTERNAL INFORMATION Northern Extension of Northolt Tunnel SIFT Report
C222-ATK-DS-REP-020-000034 Revision – P06
Page 45
Uncontrolled when printed INTERNAL INFORMATION
Key Sustainability Issue Topic STAGE: Constructio n or Operation EDA Considered (incl. Topic and Ref no.) Comment QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG Proposed Scheme during construction. There will be adverse landscape impacts upon all Landscape Character Areas and visual impacts on receptors located within the vicinity of the site during the construction phase.
Due to the magnitude of change and the sensitivity of these areas there will be a moderate or major adverse effect on the aforementioned LCAs.
Op
There will be adverse impacts on the following LCA during operation, Harefield Farmland LCA, Colne River Valley LCA, Colne Valley LCA, Maple Cross Slopes LCA and Chalfont St Peter LCA. The operational impacts will arise from newly engineered landforms and structures cutting across the existing landscape including a new viaduct with associated infrastructure. This will result in effects ranging from major to moderate at year 1. By year 15 and 60 all effects experienced by the LCAs are deemed to be non-significant except for those in Harefield Farmland LCA (which only become non- significant by year 60) and Colne River Valley LCA (which remains significantly affected in year 60).
There will be adverse visual impacts experienced by the following (but are not limited to) residents of South Harefield, Harefield, Denham Green, recreational users of the Colne Valley lakes and local footpaths. There will also be permanent land severance, the introduction of noise fence barriers, of highway infrastructure into the semi-rural environment including road bridges, of overhead power lines and the introduction of regular high speed trains. This will result in adverse visual impacts and significant effects. o With careful mitigation design of the landform surrounding the open gap section it would be possible to mitigate this feature within the local landscape and screen key viewpoints. Vent shafts can be designed to mirror the local vernacular and screened with planting and/or landform to minimise their long term impact. Within the base case the National Grid pylons were diverted away from the Colne Valley Lakes which was a beneficial with this option this would no longer occur.
+++ As Option B. +++ `Code 1 -
Accepted Uncontrolled when printed INTERNAL INFORMATION Northern Extension of Northolt Tunnel SIFT Report
C222-ATK-DS-REP-020-000034 Revision – P06
Page 46
Uncontrolled when printed INTERNAL INFORMATION
Key Sustainability Issue Topic STAGE: Constructio n or Operation EDA Considered (incl. Topic and Ref no.) Comment QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG QUALITATIVE IMPACT DESCRIPTION and/or QUANTITIVE ASSESSMENT RATI NG
At a number of locations, views of the Proposed Scheme will be filtered or screened by intervening lakeside vegetation. The retention of intervening hedgerows, trees and the reestablishment of lakeside vegetation will further reduce adverse impacts over time. The proposed planting of the approach embankments will help further screen the proposed viaduct. However, in certain locations it is not possible to screen or filter views of the viaduct because of the open nature of the view as it spans the Colne Valley Lakes. In such instances significant effects will continue even by year 60 of operation.
Cultural heritage Const
CH1, CH4, CH5
Savay Farm (an asset grouping of high value), a scheduled monument located south of Savay Farm, Pynchester Farm, the Grade II listed Highway Farmhouse, St Leonards Farmhouse and Brackenbury Farm will be temporarily impacted by the high visibility of construction activities and associated disturbance will impact the setting of these assets. The following archaeological assets will be directly impacted by construction: • buried archaeological remains associated with the Mesolithic activity at Dew’s Farm (major adverse effect); • Palaeolithic artefacts and deposits within the Thames Terrace deposits (moderate adverse effect); • prehistoric to Roman archaeological remains at Denham Park Farm and Chenies (major adverse effect); • buried archaeological remains of the former post-medieval garden at The Fisheries (moderate adverse effect); • approximately 1ha of ancient woodland at Battlesford Wood(moderate adverse effect); • archaeological remains of the former 19th o There is a potential to remove significant archaeological remains during groundworks associated with the 700m gap to the south of the Chiltern tunnel southern portal and the Rail Head and ventilation shafts.
The sustainable placement would impact the setting of the scheduled monument Brackenbury Farm moated site. It would also affect the listed buildings St Leonards Farmhouse and Copthall Farmhouse. The sustainable placement would also have a permanent impact to the site of a Romano British settlement.
Overall the construction impact of this option is significantly reduced compared to Option A.
+++ As Option B. +++ Yüklə 0,76 Mb. Dostları ilə paylaş:
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