Hartington Reclamation Site, Derbyshire by BSG Ecology and Tawnywood Ltd
Shortlisted for Brownfield Awards Category 12 - Best Biodiversity Enhancement
Hartington Reclamation Site is located near Chesterfield, Derbyshire. The site, 26ha in area, is made up of disused former foundry tips, industrial plant, and a partially restored former deep mine tip, buried under made-up ground.
The Site’s owner and developer, Tawnywood Ltd, obtained planning consent in 2017, subject to a Section 106 agreement, to reclaim and restore the site to provide land for commercial development; this would be achieved through the excavation of areas of coal by opencast methods, including the diversion of 200m of the River Rother, and by processing the foundry tips to produce secondary aggregates suitable for use by the construction industry.
The proposed development was strongly supported by both Chesterfield Borough Council and Derbyshire County Council. The planning authorities viewed the development as a significant part of their regeneration programmes; it was allocated in the Local Plan for employment purposes.
Biodiversity has been a key factor in the project and, while the regeneration of this brownfield site has had an unavoidable initial impact on existing habitat features, a comprehensive programme of mitigation, compensation and enhancement, and long-term management for biodiversity has been put together by BSG Ecology.
This has involved work at three additional sites, all under the control of the developer, which has provided a unique opportunity for off-site biodiversity compensation in close proximity to the development site. Extensive consultation and collaboration with Derbyshire County Council and Derbyshire Wildlife Trust, Natural England, parish councils, and local community engagement drove the preparation of a high quality scheme. The resulting strategy (Landscape and Ecological Management Plan) is now being delivered.
Photograph 1: Dingy skipper
BSG Ecology’s involvement in the project started in 2010 when initial baseline surveys were commissioned: an extended Phase 1 habitat survey, followed by botanical survey, surveys for invertebrates, and survey for other protected species including badger, otter and reptiles. Our role at this point was to determine the ecological constraints present, their significance and how they should be addressed, taking into account relevant wildlife legislation, policy and industry guidance.
It became clear that there was significant ecological interest within areas of the site: a number of important habitats were present including Local Wildlife Site (LWS) quality species-rich neutral grasslands and open-mosaic habitat on previously developed land, a habitat type which is frequently found on brownfield sites and which is a Habitat of Principal Importance under the NERC Act 2006. Open mosaic habitats are typically subject to previous disturbance (soils being mixed, removed or modified, or through the addition of spoil) with spatial variation, allowing different habitats to occur in close proximity. This diversity typically provides good habitat for invertebrates.
The site was found to support a diverse assemblage of invertebrates (over 250 species). Several rare species were recorded, including the butterfly dingy skipper Erynnis taeges, a Species of Principal Importance that is often associated with ex-colliery sites. Key habitats for invertebrates were recorded on the spoil mounds and surrounding habitats; 30% of the site was assessed to provide good invertebrate habitat. Since these areas would be affected by the development, the potential impact on the invertebrate assemblage was assessed to be significant.
Photograph 2: Typical open mosaic habitat at Hartington Reclamation Site prior to stripping
Detailed consultation was undertaken with Natural England, Derbyshire Wildlife Trust and Derbyshire County Council during the pre-application design stage, while BSG Ecology and Tawnywood’s project team worked closely to address the biodiversity concerns, identify mitigation options and to determine a way forward which would allow the development to go ahead and provide certainty on the delivery of a high quality mitigation package. This would need to provide compensatory open mosaic habitat, new areas of species-rich grassland, provide structural variability, microhabitats and the food plant for dingy skipper (bird’s-foot trefoil). The mitigation scheme would also need to ensure that impacts on other protected species were avoided. BSG Ecology was commissioned to prepare the mitigation strategy.
Mitigation strategy: translocation, compensation and enhancement
Since the majority of the Site was going to be affected first by the mineral extraction, and then subject to development, it was clear that an off-site solution was needed. Tawnywood’s commitment to secure and deliver long-term management led to the identification of three nearby receptor sites within their landholding, all within 1.2km of Hartington and were unmanaged:
Site 1: Campbell, a former landfill site 10.3ha, 1.1km to the west. This site was to receive translocated habitats - grasslands, open mosaic habitat and materials selected for their intrinsic botanical interests and for invertebrates.
Site 2: Troughbrook Road 1.9ha, 1.2km to the southwest. This site was to receive wet grassland, new areas of grassland seeding and hedgerow planting, and enhancement of existing grassland by management.
Site 3: Breck Farm Water Meadows 14.8ha, 400m to the north. This existing LWS (for invertebrates) was to be brought into management to improve and enhance the condition of the grassland, hedgerow and ox-bow lakes for aquatic invertebrates and wading birds.
Baseline survey work was undertaken by BSG Ecology to confirm the suitability of the sites. A key benefit of the off-site compensation areas was their immediate availability; the translocation of soil materials and vegetation and creation of new habitats would aid the colonisation of flora and invertebrates in the receptor sites before the existing habitats at Hartington were removed.
In addition to habitat translocation, the mitigation at Campbell and Troughbrook involved hay-crop seeding, willow tree, scrub and hedgerow planting.
A key element of the project design was that no new materials were required: all suitable substrates, including crushed brick rubble, spoil and soils, from Hartington were re-used at the receptor sites and these materials were also used as the primary source of seed bank material for vegetation establishment. This removed the costs of removing waste materials, and avoided the need to obtain any new substrates.
At Breck Farm, the mitigation strategy involved management and enhancement, including the creation of complex of wetland habitats to complement the existing ox-bow lakes and wildflower grassland creation. BSG Ecology’s entomologist worked closely with Tawnywood to design the receptor site topography and habitat layouts. Method statements were prepared to describe the work required to establish the habitats and detail their on-going management. The complexity of the habitat translocation is demonstrated at Campbell.
The end use for the three sites is entirely for biodiversity purposes. The receptor sites are not publicly accessible, although the Campbell Site is adjacent to a public footpath, visible from local residential properties and is accessed informally by local residents. The Campbell Site has been carefully landscaped, taking on board comments from Derbyshire County Council’s landscape architect, to ensure the landform provides a pleasant view for the residents of Barrow Hill.
In addition, mitigation will be incorporated into the development site when restored through the creation of 22m-wide margins of species-rich habitat grassland, and open mosaic habitat within a 5m strip of retained vegetation around the edges of the completed development, and through river corridor enhancements: new swales seeded with wildflower grassland and new woodland planting around the river channel.
Photograph 3: The development Site (red) and receptor sites (blue)
Implementation: delivering mitigation
Since securing planning consent, emphasis has been placed on discharging planning conditions. The main contractor tasked with the implementation of the mitigation strategy, Fitzwise Ltd, is a sister company to Tawnywood; both firms have long-standing relationships based on previous collaborative work. A great benefit of this is a common understanding of the work required and a high-level of co-ordination; this has avoided delays and aided the efficient and cost-effective delivery of works on the ground.
A Hartington Liaison Group has also been formed, which meets twice annually. It provides an opportunity for community engagement and a mechanism for direct liaison between the project team and contractors, and other groups including Parish Councils, local individuals, Chesterfield Borough Council and Derbyshire County Council. The most recent site meeting was led by BSG Ecology in September 2019 to show the work undertaken at Campbell and Troughbrook, which was received enthusiastically.
Photograph 4: Hartington Reclamation Site - works underway
Following the translocation of materials from Hartington Reclamation Site to Campbell and Troughbrook in 2018, significant progress has been made on over the last year:
Annual monitoring of the translocated habitats using fixed point marker posts and photography commenced in August 2019. Further visits were carried out in September 2019 and April 2020. An annual monitoring report is prepared and issued. At Campbell the monitoring target for plant species diversity to be of LWS quality has already been achieved after one year. The translocated vegetation is developing at Troughbrook.
Specific areas of Campbell and Troughbrook were seeded with a wildflower mix in autumn 2019. Initial ground preparation at both sites involved the removal of the existing vegetation and the top 2 cm of topsoil to reduce the prevalence of tall herbs, including thistles. The soil was prepared to receive the broadcasted wildflower seed. Following the landscaping operations, two wetter areas at Campbell are developing and adding habitat diversity; these will be maintained.
Creating conditions suitable for dingy skipper at Campbell and Troughbrook: Dingy skipper requires an abundance of the larval food plants, including bird’s-foot -trefoil. A sparse sward, usually including sunny open bare ground is preferred; patches of taller vegetation provide shelter and roosting sites. Areas of selected mounds were subject to further modification in 2019 to increase the area of prevalence of suitable habitat. The botanical monitoring has found that bird’s-foot trefoil has colonized Campbell.
Scrub planting: scrub, grey willow and hedgerow planting took place at Campbell and at Troughbrook in autumn 2019.
A ditch at Troughbrook has been blocked at intervals to enable seasonal flooding of an area of grassland in autumn 2019 to create damp/wet grassland conditions.
Photograph 5: Campbell Site, showing a patchwork of translocated materials to create variation and edge effects
Other work underway at the Hartington Reclamation site includes the provision of an otter ledge as part of the new river bridge installation; bat roost features will also be installed into the bridge. Riverine woodland, ponds and swales and river banks along the new River Rother diversion were planted and sown in spring 2020.
On restoration, the three development platforms will be seeded with a grassland seed mix until they are developed, to provide additional temporary habitat for invertebrates.
Project outcome: Biodiversity protection, restoration and development
Tawnywood Ltd, BSG Ecology and Fitzwise, pro-actively addressed the ecology issues working collaboratively with decision makers and the local community. We applied the NPPF mitigation hierarchy effectively to avoid harm where possible, provide mitigation and compensation, both on and off-site, and to provide enhancements to provide biodiversity benefits that will be managed into the long-term in four locations.
The extraction and recovery of the mineral products will cover the costs of the site’s restoration and the project has made good use of the existing resources to translocate materials and to create new habitat features. A long-term financial benefit will be achieved through the commercial development which will bring employment and add value to the local area.
Photograph 6: Bird’s-foot trefoil establishing in translocated materials at Campbell
Planning consent information:
The Recovery of secondary aggregates, opencast coal and ancillary development at Hartington Reclamation, Farndale Road, Staveley. Application Code: CM2/0911/81.
Ecological enhancement scheme for the former Campbell Landfill Site and Troughbrook Road former opencast site, Campbell Landfill Site, Staveley Lane and Troughbrook Road. Application Code: CM2/0213/144.