Habitat management and creation Ketton Quarry

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1 Habitat management and creation Ketton Quarry Name of the plant Castle Cement Ltd Ketton Works and Grange Top Quarry Location Ketton Village Stamford Lincolnshire Size 500 ha Mineral Type Limestone and shale Partial Living Space in Ketton Woods SSSI. Lake acting as a sump for quarry floor dewatering now a important wildlife habitat. We are reliving the natural aquifer from a series of springs which we collect within the lake. Habitats created Restoration to Wolds Mosaic Landscape Calcareous Grasslands Woodlands Water bodies Roadside verges Bat Caves Partial Living Spaces Mineral Planning Authority Rutland County Council Background information Grange Top Quarry is a large (over 500Ha) shallow strip mine yielding approximately 2.5 million tones per annum of mid Jurassic limestone and shale providing a feedstock to the adjacent Ketton Castle Cement works. Ketton provides about 11 per cent of the UK's total requirement of cement, primarily to locations in central and southern England. Not all of the stone quarried at Ketton is used to make cement. The site is also noted for its attractive and light colored material known as Ketton Freestone which has been used in fine architectural buildings since the 16th century. The Freestone is an oolitic limestone and is able to be cut and shaped into blocks for use as a much sought after building stone. Grange Top quarry is home to 26 different species of butterfly and a large number of birds, including nightingales as well as a mosaic of many different habitats. It also possesses a glow worm colony.

2 Ketton Freestone. Source: G. Lucas Planning History Cement has been manufactured at Ketton since 1928.The existing quarries lie to the north and north west of Ketton village and noted on the National Grid reference at SK The consented quarry is registered with the PA under an IDO Permission and an second Consent for additional mineral reserves granted in 2002.Existing reserves extend to approximately 15 years supply dependant on extraction rates. The calcium bearing component for cement is recovered from the Lincolnshire limestone formation (Jurassic series) and the clay material bears the silica, alumina and iron oxides which is a component of the overlying layers in the Rutland Formation. Habitat design The quarry lies a few kilometers to the east of Rutland Water, one of the largest man-made reservoirs in Europe and is set in a typical Lincolnshire Wolds landscape consisting of rolling arable agricultural fields bounded by hedgerows and interspersed with deciduous woodlands. The underlying Jurassic limestone and shale sequence is relatively thin and the large tonnage yield requires the quarry faces to advance at a rapid rate leaving behind large flat areas ringed by roughly horizontally bedded cliffed boundaries. The rapid rate of advance presents a challenge to the continuous restoration process as well as many opportunities for extending the biodiversity. The habitat management and restoration schemes aim to retain existing woodlands, isolated trees and hedgerows where possible and maintain them together with appropriate planting and landscaping of worked areas. The central part of the permission contains the Ketton Quarries SSSI. The citation for the SSSI lists the Jurassic geology and the complex mosaic of grassland,

3 scrub and woodland developed on disused pits and spoil tips as the reasons for its importance. This citation underlines the significance and evolution of partial living spaces in the quarrying dimension. Partial living spaces are defined as the results and effects of quarrying and processing activities which might provide ephemeral habitats, and in some cases, such as the Ketton SSSI, evolve into precious islands of enriched biodiversity over time. Taking all of this into account, and in consultation with interested partners, this has informed the habitat creation schedule at Ketton. Typical Wolds landscape with a mosaic of wildlife habitats Source: G. Lucas. Habitat creation details The diversity of landscape and habitats consumed by the extraction activities has resulted in the need for a composite approach to restoration and the development of biodiversity. In the case of Ketton the aim is to recreate and enhance the mosaic of habitats that have been disturbed. This is being achieved by nurturing the following habitats: Restoration to Wolds Mosaic Landscape. The indicative restoration plans developed in a partnership with Castle Cement, English Nature, consultant ecologists and landscape architects aims to recreate the typical patchwork of a Wolds rolling landscape with its hedgerows, tree stands, scrub and agricultural fields (arable and sheep pasture) and an orchard (important for insects). In terms of biodiversity this offers the myriad of habitats and interconnections. Calcareous Grasslands. A small area of species poor calcareous grassland has been worked and replaced by approximately 30Ha of created grassland with a natural grass mixture sown or translocated onto a calcareous substrate (using overburden from the overlying Blisworth Limestone). Recent work by Harry Ball of the Leicestershire Entomological Society has identified a breeding colony of the four spotted moth (Tyta luctuosa). Hedgerows. These create the landscape mosaic effect and are important elements of the biodiversity especially when enclosing

4 monocultural arable fields. Hedgerows provide havens for birds, insects and act as bat flyways. Bats use linear features to guide their flight paths whilst hunting for insects and returning to their roost sites. Hedgerows provide the linear markers and also host insect populations as an important feedstock (a bat can consume 3000 insects in one night). About 5Km of hedgerows are being recreated and maintained to ensure continuity of this habitat. Woodland. A number of woodland stands will be removed for the workings. Saproxylic habitats (rotten wood with insect populations) are being translocated to new or existing woodland areas. Woodland soils and their inherent flora and fauna are also being trans-located. New woodland is to be planted (c. 35Ha) and in areas of cut troughs rides will be created to encourage secondary succession of woodland vegetation communities. Trees can provide important bat roosts and this has been mitigated and explained in the next point. Bat Caves. Extraction inevitably disturbs habitats. In mitigation and habitat gain an engineered bat cave was created in 2000 on the site by Castle Cement. Some 63 meters long and housed in a shelter leading into drilled mine adits this provides a temperature controlled environment for bats to roost and breed. Devised by a leading specialist, Dr Bob Stebbings, this unique habitat is safeguarded by a grilled entrance and monitored by an infrared curtain which records bat passes. In addition a nearby abandoned freestone mine on the Castle Cement property has been secured as a bat sanctuary with the same security and monitoring. Together these two creations provide a valuable mitigation and extension of an habitat for the 16 species of British bats which have seen a significant reduction in numbers in recent years and are now heavily protected by law. Left: Ketton Bat Cave constructed Right: Edith Weston freestone mine and natural bat cave. Source: G. Lucas. Water Bodies. Water bodies are rare in Wold landscapes except for the traditional dew ponds created by farmers or where impermeable shale crops at the surface in dips and collects water. Extraction at Ketton is taking place at or near the water table and to assist water management a lake has been created north of the SSSI site acting as

5 a runoff sump, water supply point for dust control. In turn this partial living space has evolved into an important wildlife habitat for birds, insects and bats. A dew pond using traditional puddled clay has been created near the freestone mine to provide insect populations for the bats, and has attracted damsel and dragonflies. Other water bodies exist on site including a large water table moderated lake in the northern abandoned part of the site. Roadside verges. The permission requires the rerouting of a road. Roadside verges are important corridors of wildlife providing they are left untreated. In recognition of this the roadside verges will be moved lock, stock and barrel and translocated to their new positions to maintain the existence of this valuable habitat. Roadside Verge Nature Reserve. Source: G.Lucas. Partial Living Spaces. Extraction inevitably creates habitats which by their very nature are ephemeral or fragmentary ( e.g. a rock face and bench) They should not be discounted as important parts of the biodiversity and require recognition and management. Soil piles, standoffs, bunds, standing water, quarry faces, tracks, wheel ruts, and sumps all provide opportunities for wildlife habitats. At Ketton worked areas to the north of the current extraction offer excellent examples of these habitats. Cliff faces in limestone and shale, (and indeed cement work facilities) support falcons?, kestrels, and martens. Soil piles host a diverse collection of plants, insects and birds. It is important to realize that to a casual viewer that these spaces appear to be waste lands in need of restoration to manicured landscapes but they are perhaps the most important wildlife refuges and one of the strongest biodiversity indicators in the extraction and worked areas.

6 Calcareous Grassland and Partial Living Spaces. View of Grange Top quarry looking south. Source: G. Lucas. Long-term management and monitoring The permission conditions require significant management, monitoring and reporting of the disturbed and recreated habitats, A Habitat Management Scheme engineered by consultants and steered by partners delivers the successful outcomes. Research projects by consultants and university links explore and inform specific elements of the scheme. Geographical Information Systems have been adopted by the quarry management to store, coordinate and share the habitat data collected during the evolution of the Habitat Management Scheme. Public benefits The Company wishes that the community is rarely if ever disturbed by the extraction and all plans are devised with this in mind. However in a sphere of total openness and commitment to involve Ketton Castle Cement have Helped maintain the Ketton Quarries SSSI in tandem with Leicester & Rutland Wildlife Trust. Helped with funding of the Ketton Geological Trail in the SSSI.. which is important in the sense that it provides the substrate for the biodiversity and demonstrates the link between geo and biodiversity Encourages quarry visits for the public and school parties Maintain a biodiversity that probably goes unnoticed to most of the surrounding population.. but might not if local apple trees were not pollinated for example by the profusion of insects maintained on site National Insect Week Bat cave visits (exterior only)

7 Annual Open Day to showcase quarry activities Close working links with local conservation groups to protect the flora and fauna Rerouting of Rights of Way and storyboards explaining the biodiversity Public Information Display - storyboard. Source: G Lucas Contact information Gerry Lucas lucasg@edgehill.ac.uk