LAND NORTH OF COXFORD ABBEY QUARRY, SOUTH OF FAKENHAM ROAD (EAST RUDHAM): POTENTIAL ECOLOGICAL IMPACTS OF EXTENDING QUARRY INTO CONIFER PLANTATION DESIGNATED AS PAWS

BACKGROUND
Norfolk County Council Minerals and Waste Local Plan Initial Consultation May 2018 concludes that the above site is unsuitable for allocation because it is largely on an area of Plantation on Ancient Woodland Site (PAWS).

Longwater Gravel Co. Ltd instructed SLR Consulting Ltd to provide a short factual report reviewing SLRs ecological work to date at the site, and briefly considering the ecological impacts of extending Coxford Abbey Quarry ("the Quarry") into the area of coniferous plantation, designated PAWS.

This letter report has been prepared by Jess Colebrook CEnv, MCIEEM and draws upon field survey reports and literature review undertaken by SLR in 2013 to inform the Ecological Impact Assessment process undertaken in respect of quarry extension.

DESCRIPTION OF PAWS AT COXFORD ABBEY QUARRY
A block of 20.6ha of woodland identified1 as Plantation on Ancient Woodland Site (PAWS) occurs at the north of the quarry, and is known as Coxford Wood.
The term Ancient Woodland is applied to sites in England and Wales whose documented history shows them to have been continuously wooded since approximately 1600, and which are by extension considered likely to have been continuously wooded since the last Ice Age. Research on the Coxford Wood site history includes Faden's map of Norfolk published in 1797 and 19th century
tithe and enclosure maps which show woodland boundaries that correspond closely to the area designated as PAWS. The First series OS Plan dated around 1880 shows the PAWS area with new plantation to the east north east and south. It is interesting to note that the detailed cartography of the time shows the PAWS area with a significant proportion of conifers. These cannot be the trees currently in place as these date from the late 1960's to the early 70s, so it seems the PAWS area has seen at least two conifer rotations.

The majority of Coxford Wood is now plantation woodland dominated by Scot's pine Pinus sylvestris with Douglas fir Pseudotsuga menziesii, oak Quercus robur, beech Fagus sylvatica, silver birch Betula pendula, sweet chestnut Castanea sativa and rowan Sorbus aucuparia recorded. The proportion of conifers in the canopy is high throughout the woodland and typically exceeds 90%. Woodland understory is typically sparse throughout the wood and species lists from all field surveys conducted in Coxford Wood have been reviewed for records of Ancient Woodland Indictor (AWI) species in East England (Rose, 2006; as cited by Rotherham, 2011) for flora associated with ancient woodland sites.

Only three AWI species have been recorded from the site: climbing corydalis Ceratocapnos claviculata; holly Ilex aquilifolium and rowan Sorbus aucuparia. This is a very low number of AWI species for an ancient woodland site and indicates that the woodland's past management, anecdotally reported to have included two rotations of conifers, has clearly had an adverse effect upon the biodiversity value of the woodland habitat present.

Coxford Wood, including PAWS, is considered to be of Parish Value. It is unlikely to meet CWS guidelines for woodland habitats5 as it is currently in poor condition due to dominance by coniferous species and as a result of two conifer rotations reducing ground flora richness.

POTENTIAL IMPACTS OF QUARRY EXTENSION INTO PAWS
Do nothing scenario:
Commercial forestry is typically managed on a 30-60 year rotation, and therefore it is highly likely that the current tree crop including the PAWS, would be felled and replanted at some point in next 20-30 years. The felling and replanting of forest, would further disrupt the soils in ancient woodland areas, but may be an opportunity to replace mixed and coniferous stands with native broadleaves.
However, the landowner is likely to wish to maximise commercial land values and therefore another conifer rotation is more likely than a switch to lower yielding broadleaves in the absence of other drivers.

Habitat Loss, Fragmentation and Isolation due to land take
Due to its management in the last century, the biodiversity value of PAWS in Coxford Wood is considered to rest within its soils. Field surveys of the PAWS woodland have not identified any specific features indicative of ancient woodland, such as ancient or veteran trees or a diverse flora of
AWI species. In the absence of any mitigation, it is predicted that the permanent loss of soil resource
from the majority of the PAWS as a result of quarry extension would be considered an adverse
impact significant at a Parish level.
It is proposed that top-soils from the PAWS would be stripped in a phased manner and direct placed onto pre-prepared restored areas in advance of replanting with broadleaved trees which would be managed to recreate Coxford Wood, in accordance with an agreed Woodland Management Plan.
This approach to phased development, restoration and long-term management would give the best opportunity to maintain any seed bank and functional soil micro-organisms within the translocated soils and for the restored woodland habitats to maximise their biodiversity potential. A review of literature and guidance on the translocation of ancient woodlands and their soils was undertaken by SLR in 2013 (Unpublished report, refer to Appendix 1 of this report for a full list of key sources) provides evidence that this approach to compensation for the loss of the PAWS habitat has a high chance of successfully maintaining the residual value of the soils and restoring a native woodland to replace the non-native plantation currently present.
With these measures in place and the implementation of a woodland management plan, the residual effects upon woodland habitats, including PAWS, are not considered significant.

Restoration Scheme
Proposed mineral extraction on the site would provide a catalyst for the transformation of a commercial, mainly conifer woodland to native broadleaved woodland over the restoration period.
The process of PAWS soil translocation and the commitment to the long-term management of woodland habitats would produce substantial gains in terms of biodiversity value in the long-term and is considered to provide a net positive impact for biodiversity that is significant at a Parish level.

Residual Impact
In this instance, the PAWS at Coxford Abbey Quarry is considered to be of low biodiversity value and its loss to quarrying and the restoration of the site to a native woodland is not considered to be significant in biodiversity terms when compared to the predicted baseline and "do nothing" scenario.

CONCLUSION
The proposed development would lead to the predicted loss of Plantation on Ancient Woodland Site as identified on the Ancient Woodland Inventory. In biodiversity terms, PAWS at Coxford Abbey Quarry is considered to be of low biodiversity value and its loss to quarrying and the restoration of the site to a native woodland is considered not significant when compared to the "do nothing" scenario.
The ecological assessment has identified no residual impacts of habitat loss and fragmentation upon woodland or other habitats of ecological value. Long-term management commitments and restoration of woodland areas would ensure that adverse effects upon important receptors are minimised. The proposed restoration and 20-year management plan is considered to generate net biodiversity gains at a local level in comparison to the predicted baseline.
CLOSURE
This report has been prepared by SLR Consulting Limited with all reasonable skill, care and diligence, and taking account of the manpower and resources devoted to it by agreement with the client.
Information reported herein is based on the interpretation of data collected and has been accepted in good faith as being accurate and valid. SLR disclaims any responsibility to the client and others in respect of any matters outside the agreed scope of the work.