13. ENVIRONMENTAL IMPACTS TABLE

This chapter presents the Environmental Impacts Table (Table 13.1) for the proposed scheme. The purpose of the Table is to present the main predicted impacts (taking account of agreed mitigation) in summarised form.

The table includes the following:

Description of the potential impact;
Mitigation objective and commitment;
Sensitivity/value of the receptor;
Duration of the impact;
Magnitude of the impact with mitigation in place; and
Significance of the impact with mitigation in place.

DMRB guidelines state that the 'do nothing' or ‘do minimum’ options should be included in the Environmental Impacts Table. However, in this particular circumstance, do nothing or do minimum would mean putting a weight restriction on the bridge which is not considered feasible as it is a main Trunk Route. Therefore, the ‘do nothing’ and ‘do minimum’ options have been omitted from this table.

The Environmental Impacts Table includes mitigation item numbers that can be cross referenced to specific mitigation measures in Table 14.1.

Table 13.1 Environmental Impacts Table

Potential Environmental Impact	Mitigation Item Number (refer to Table 13.1)	Sensitivity/ value of Receptor	Residual Impacts
Potential Environmental Impact	Mitigation Item Number (refer to Table 13.1)	Sensitivity/ value of Receptor	Duration of Impact (short/long term)	Magnitude of Impact (after Mitigation)	Significance of Impact (after Mitigation)
Geology and soils
Slight re-grading of embankment and drift-deposit slopes resulting in a slight loss of minerogenic material from the drift-deposit slopes and the covering and possible compaction of peat beneath the widened embankment slopes.	3, 4, 17	low	long term	minor	slight
Excavation of drift deposits will result in a small loss of minerogenic material and supporting soil, with associated localised changes to hydrology	1, 10, 15, 16, 52	low	short term	minor	negligible
Excavation of peat will result in a small loss of organic material, and a slight localised change to peat structure and hydrology.	1, 2, 5, 8, 9, 10, 12, 13, 14, 15, 16, 18, 52, 53	high	short and long term	minor	slight
The cutting of two moraines will result in a small loss of minerogenic material.	11, 12, 14	low	long term	minor	negligible
Disturbance of peat, through compaction and loss of structure caused by the movement of plant and construction staff around the site	67, 68, 71	high	long term	negligible	negligible
Road Drainage and the Water Environment
Sediment release from construction activities and bare areas of soil affecting water quality	13, 14, 15, 19, 20, 21, 22, 23, 24, 25, 26, 30, 33, 34, 68, 69, 70, 75, 77	high	short term	negligible	negligible
Coarse sediment delivery not removed by low competency river flow	13, 14, 15, 19, 20, 21, 22, 23, 24, 25, 26, 30, 33, 34, 68, 69, 70	high	long term	negligible	negligible
Sediment loading smothering habitats and affecting the breathing apparatus of fish and aquatic invertebrates	13, 14, 15, 19, 20, 21, 22, 23, 24, 25, 26, 30, 33, 34, 68, 69, 70, 75, 77	high	short term	negligible	negligible
Discolouration from silt and clay sedimentation	13, 14, 15, 19, 20, 21, 22, 23, 24, 25, 26, 30, 33, 34, 68, 69, 70	high	short term	negligible	negligible
Reduction of fish spawning ground from sediment filling voids	13, 14, 15, 19, 20, 21, 22, 23, 24, 25, 26, 30, 33, 34, 68, 69, 70	medium	long term	negligible	negligible
Introduction of coarse, angular, foreign sediment from the demolition of the bridge	19, 20, 21, 22, 25, 30, 34, 36, 37, 68, 70	high	long term	negligible	negligible
Delivery, storage and removal of large quantities of stone and aggregate may result in the transfer of some of the material to the river channel	15, 19, 20, 21, 22, 24, 26, 68, 69, 75	high	short term	negligible	negligible
Vehicle movement will transfer fine sediments around the site that could be washed into the channel	12, 19, 23, 24, 30, 33, 35, 75	high	short term	negligible	negligible
Ecology and Nature Conservation
~ 5 m² of habitat loss	1, 2, 5, 6, 7, 8, 9, 10, 12, 13, 14, 38,, 41, 43, 52, 53, 71, 75	medium	long term	minor	slight
Temporary impacts to wetland habitats from construction activities, including pollution, siltation, spray and runoff	19, 20, 21, 22, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 67, 68, 69, 70, 75	high	short term	negligible	negligible
Fluvial and Aeolian deposition of construction materials onto semi-natural habitats	8, 10, 11, 12, 13, 15, 23, 45, 46, 49, 69, 75	medium	short term	negligible	negligible
Possible loss of trees	38, 39, 75, 78	medium	long term	moderate	slight
Disturbance to mammals (if present) by construction	39, 41, 42, 75, 76, 78	high (if present)	short term	minor	slight
Possible disturbance to aquatic wildlife	See water environment section above	very high	long term	minor	slight
Landscape and Visual
Disturbance to the tranquil character of the area by the presence and activities of major construction plant and workforce	42, 54, 55, 56, 57	high	short term	moderate	slight
Detraction from the natural landmarks and scenic beauty of the area	27, 43, 61, 64, 65, 73	high	short term	moderate	slight
Loss of roadside mire, heath, peat and drift deposits	As for geology, geomorphology and Soils section	medium	long term	minor	slight
Potential pollution of River and Loch Ba	As for Ecology and Nature Conservation section	high	short term	negligible	negligible
Very minor loss of moorland vegetation, minor loss of willow carr and individual birch and rowan adjacent to the bridge	As for Ecology and Nature Conservation section	medium	long term	minor	slight
Changes to the character of the area due to the use of new, non-local materials, particularly the concrete, tubular rail parapet and steel girders to support the new, wider bridge deck	74	high	long term	minor	slight
Disruption Due To Construction
Temporary requirement of some peatland/moorland for the temporary bridge and works	See Geology, Geomorphology and Soils section	high	short term	minor	slight
Some pedestrians and cyclist’s journeys within the vicinity of the proposed scheme will be longer, delayed, obstructed, noisier and subjected to a loss of amenity	58, 59, 60, 62, 63	low	short term	minor	slight
Pedestrians and others, if using the A82, will be proximal to plant, construction activities and motor vehicles whilst passing through the traffic management	67	low	short term	minor	slight
Parking and thus access to paths will be affected due to the location of the site compound	61	low	short term	minor	slight
Temporary alteration to drivers views	61, 62	high	short term	minor	slight
Increase in driver stress from construction activities and delays	58, 60, 61, 62, 63, 64, 66, 67	low	short term	minor	slight
Impacts on the water environment similar to those discussed above	As for Ecology and Nature Conservation section	high	short term	negligible	negligible
Planning Policies
No predicted impacts