Environmental Statement Volume 1 - Dorsetforyou.com

Chapter Nine – Ecology and Nature Conservation9.98 During construction and throughout operation of the Schemesteps would be taken to prevent impacts upon habitats or speciesfrom pollution including construction dust and polluted water run-offfrom the road through adherence to necessary procedures and goodpractice guidelines. Road water run-off would be appropriatelytreated and directed to balancing ponds along the Scheme.9.99 A watching brief would be maintained for protected speciesup to and during the construction period and steps taken to ensureearly erection of fencing, translocation of species etc. to ensureprotection from Scheme construction. All works would take regard ofthe appropriate seasons for protected species work.9.100 The specific mitigation steps proposed are presented inVolume 2: Ecology and Nature Conservation but would include theinstallation of crossing points for badgers, a partially vegetatedbridges to guide bats across the Scheme and the design of shelvesand scallops in exposed chalk cuttings to allow plant communities toestablish.Impact AssessmentOverview9.101 The impacts of the Scheme on the ecological resource aredescribed below, and are summarised in Table 9.6. The Scheme hasthe potential to cause a range of both temporary and permanentimpacts on the nature conservation resource, including:• the direct loss of habitat;• disturbance to wildlife during construction and operation bynoise, vibration, lighting and movement;• pollution risk from runoff, liquids carried by vehicles, gaseousemissions;• the risk of collision between fauna and road traffic.9.102 However, the Scheme also represents an opportunity toprovide nature conservation benefits through appropriate mitigationmeasures, sensitive Scheme design and the provision of valuablehabitat within the Ecology Mitigation Area and along the Scheme.These are described below and form part of the overall assessment.Impacts on Designated SitesLorton SSSI9.103 At Two Mile Coppice, approximately 0.6 ha of SSSI woodlandwithin Lorton SSSI would be lost to the Scheme of which 0.25 ha isancient semi-natural woodland and 0.35 ha is more recent or infillwoodland. Land take would be kept to a minimum by keeping theScheme as close to the railway line to the west as is feasiblypossible. Indirectly, noise from construction and from the operationalScheme may have disturbance impacts upon wildlife using thewoodland. Pollution from road water run-off may also haveconsequences for nearby vegetation.9.104 It is not possible to directly mitigate for any loss of ancientwoodland. However in compensation for the loss and the disturbanceeffects of road noise, more woodland would be planted than wouldbe lost to the Scheme, mainly within the EMA, together with therelocation of important coppice stools into the Lorton Meadowsreserve. In addition Horse Lynch Plantation, a strip of matureplantation woodland, to the east of the SSSI would be managed forits nature conservation interests, particularly bat roosts.9.105 In removing a strip of ancient woodland and indirectlyaffecting the remainder of the SSSI woodland the Scheme wouldhave an intermediate negative impact upon the SSSI. Given that theancient woodland is considered of High nature conservation valuethe significance of this impact is considered to be moderate to largeadverse significance.9.106 Whilst the loss of a small area of ancient woodland would bemitigated by extensive new planting and purchasing maturewoodland at Horse Lynch Plantation, this would not replicate thehistorical and ecological continuity of the ancient woodland lost. Thiswould be a permanent effect upon ancient woodland of high value.This would constitute an intermediate negative impact of largeadverse significance. Once mitigation planting has matured in 50-60years time, the impact would reduce to minor negative impact and beof slight adverse significance.Lodmoor SSSI9.107 Lodmoor SSSI would not be directly affected by the Scheme.However, it would be in close proximity to the proposed Park andRide facility hence it may be affected by indirect effects of noise andpollution. In order to mitigate these effects, an earth bank wouldsurround the Park and Ride Scheme and lighting would be restrictedin location and in its operative time. Any polluted water run-off fromthe Scheme would be appropriately treated and directed to balancingponds along the route. The Scheme would also need to recap theland-fill site and in doing so would remove current pollution to theSSSI from escaping leachate.9.108 As effects upon Lodmoor SSSI will be indirect and largelymitigated it is considered that the mitigated Scheme would have anintermediate positive impact of large beneficial significance.Impacts on Vegetation & HabitatsImpacts on Woodland9.109 Indirectly, noise from construction and from the operationalScheme may have disturbance impacts upon wildlife using thewoodland. Pollution from road water run-off may also haveconsequences for nearby vegetation including mature trees. A smallwoodland at the A354 Hairpin bend in the north of the Scheme wouldbe lost.9.110 In compensation for the loss of woodland and for disturbanceeffects of road noise, more woodland would be planted than wouldbe lost to the Scheme mainly within an Ecology Mitigation Area tothe east of the Lorton SSSI. In addition Horse Lynch Plantation, astrip of mature woodland, to the east of the SSSI would be broughtinto public ownership and directly managed for its natureconservation interests, in order to provide some compensation formature woodland lost within Two Mile Coppice.9.111 In losing a strip of ancient woodland to the Scheme therewould be an intermediate negative impact upon Two Mile Coppicewhich would be of large adverse significance.9.112 Woodland of local value at West Farm would be completelylost to the Scheme, hence there would be an major negative impactupon this woodland. Woodland at Horse Lynch and CoffinPlantations and at Lorton Barn would be indirectly affected and thussubject to minor negative impacts. These impacts would be of slightadverse significance.9.113 Whilst the loss of mature woodland cannot be immediatelyreplaced, with time the extensive woodland mitigation plantingproposed would reduce the impact and in 60 years time the impactwould be reduced to minor negative upon woodland of lower value.Hence the significance of the impact would remain slight adverse.Impacts on Lower Plants9.114 A single specimen of Agonimia tristicula, a Dorset Notablelichen species would be lost to the Scheme within Two Mile Coppicebut this individual is considered to be a casual occurrence on ashort-lived habitat. A large colony exists on the abutments of therailway line and it is likely that recolonisation of moribund Elms willoccur again.Weymouth Relief Road – Environmental Statement 102