llynclys quarry restoration

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Llynclys Size 65.00 ha Location Shropshire Mineral Planning Authority Shropshire County Council Operator Tarmac Ltd Mineral Type Limestone Habitat(s) created Lowland calcareous grassland Fen Pond Hedgerow Background Limestone has been quarried at Llynclys for over 150 years. In past years the quarry operations were widely spread and included limekilns with a rail link. The extent of the operating area is now far reduced from these early days to a single office with a one-way traffic system. Llynclys quarry lies within the Oswestry Uplands Natural Area. Natural Areas are a suite of bio-geographic zones reflecting the geology, natural systems and processes in different parts of England and are used to help set nature conservation objectives. Undulating Carboniferous limestone hills with their calcareous grasslands and rocky outcrops are characteristic of this Natural Area. Neglect and fragmentation of the unimproved calcareous grasslands has made them a scarce and threatened habitat in Shropshire and therefore an important habitat for targeted restoration in local quarries. Besides the historic mineral workings, land use prior to recent quarrying was largely pastoral agricultural systems. These were based on small fields with improved grassland and some woodland. Planning history Historically in this area, quarries were simply abandoned when extraction was complete, and natural regeneration followed (see section on Llanymynech Rocks below). At the current site, proposals for nature conservation as an after-use were included within the planning application. This meant that landforming could be tailored to complement natural regeneration, maximising benefits for wildlife. Habitat creation details In-house expertise was used to develop the restoration scheme, with additional input from three recent ALSF funded projects led by Shropshire County Council (now Shropshire Council). These projects surveyed the biodiversity interest of the site and also initiated management of some previously restored areas. This included scrub Grazing, lowland calcareous grassland, environmental stewardship, natural regeneration, volunteer groups.

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case study pdf of a limestone quarry restoration

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Page 1: Llynclys quarry restoration

Llynclys

Size 65.00 ha Location Shropshire Mineral Planning Authority Shropshire County Council Operator Tarmac Ltd Mineral Type Limestone Habitat(s) created

Lowland calcareous grassland Fen Pond Hedgerow

Background

Limestone has been quarried at Llynclys for over 150 years. In past years the quarry operations were widely spread and included limekilns with a rail link. The extent of the operating area is now far reduced from these early days to a single office with a one-way traffic system. Llynclys quarry lies within the Oswestry Uplands Natural Area. Natural Areas are a suite of bio-geographic zones reflecting the geology, natural systems and processes in different parts of England and are used to help set nature conservation objectives. Undulating Carboniferous limestone hills with their calcareous grasslands and rocky outcrops are characteristic of this Natural Area. Neglect and fragmentation of the unimproved calcareous grasslands has made them a scarce and threatened habitat in Shropshire and therefore an important habitat for targeted restoration in local quarries. Besides the historic mineral workings, land use prior to recent quarrying was largely pastoral agricultural systems. These were based on small fields with improved grassland and some woodland.

Planning history

Historically in this area, quarries were simply abandoned when extraction was complete, and natural regeneration followed (see section on Llanymynech Rocks below). At the current site, proposals for nature conservation as an after-use were included within the planning application. This meant that landforming could be tailored to complement natural regeneration, maximising benefits for wildlife.

Habitat creation details

In-house expertise was used to develop the restoration scheme, with additional input from three recent ALSF funded projects led by Shropshire County Council (now Shropshire Council). These projects surveyed the biodiversity interest of the site and also initiated management of some previously restored areas. This included scrub

Grazing, lowland calcareous

grassland, environmental

stewardship, natural regeneration,

volunteer groups.

Page 2: Llynclys quarry restoration

management, hedgerow creation, pond and associated fen creation, installation of bat boxes, and provision of grazing, as well as identifying further opportunities for biodiversity and reporting on survey work undertaken. Site restoration was determined in accordance with the Natural Area status of the surrounding landscape and existing natural habitats. Considerations were also given to the hydrogeology and the type and availability of material for restoration. Since extraction at the site will intercept the water table, the restoration scheme will include an open water feature. Quarry walls have been profiled by placing material against the worked faces. This has provided an intimate mosaic of exposed face and backfilled areas as well as heterogeneity in slope and aspect. Some slopes were lightly spread with topsoil, others were left as the mineral substrate. A combination of light seeding and natural regeneration has produced good results. On parts of the site where woodland is to be created, topsoil from former woodland areas has been used and it is hoped that the existing seedbank will regenerate the ground flora. Restoration is ongoing and completed on a phased programme as faces are worked to permission limits. So far about one sixth of the 65 ha site has been restored. A diverse age range of habitat therefore exists throughout the site, with some areas having been restored over twenty years ago. The most recent ASLF funded project opened up 3.7 hectares of Calcareous Grassland, created a new pond – primarily for invertebrates – and introduced hay. Hay was taken from Sweeny Fen Site of Special Scientific Interest (SSSI) about 1km from the site to ensure local provenance of seed. This was then strewn by volunteers from Tarmac, Shropshire Council and Shropshire Wildlife Trust around the pond to encourage the development of base-rich fen.

New pond created. Dan Wrench Grazing stock were introduced in 2005 and have gradually been introduced to larger areas of the site. The stock are having a positive impact on the vegetation with previously uninteresting grassland now supporting a wider range of herb species and associated invertebrates. This has been a co-

Page 3: Llynclys quarry restoration

operative achievement between Shropshire Council, who installed fencing, and Tarmac who secured a grazier. All in a site which is still partially active.

Grazing stock at the quarry. Dan Wrench

Costs of restoration and management

Standard earthmoving equipment has been employed to carry out the landforming (360

o

excavators, articulated dump-trucks, tracked bulldozer). The success of natural colonisation is dependent on there being suitable seed/ propagule sources within the vicinity of the site. Lafarge Aggregates Limited (LAL) will fund the long-term management work under the provisions of the planning permission and the associated Legal Agreement. This will be undertaken either directly or through appointed contractors and voluntary bodies. Management planning and decision making will be undertaken in partnership between LAL and interested conservation parties such as Shropshire Council, Shropshire Wildlife Trust, Butterfly Conservation, Shropshire Biodiversity Partnership, Natural England etc. Shropshire Council has been working with Tarmac to enable a large proportion of the quarry to apply for Higher Level Stewardship (HLS) through Natural England (NE). This includes areas with existing planning conditions. The Minerals Planning Authority (Shropshire Council) have written to Tarmac and NE effectively signing-off large areas as ‘out of restoration’ to allow Environmental Stewardship schemes to take over the longer term financing of habitat management.

Page 4: Llynclys quarry restoration

Monitoring

Monitoring of the quarry slopes has shown that the seed bank in the soil has quickly regenerated with flora such as primrose, cowslip, viper's-bugloss, bird's-foot-trefoil, autumn gentian, wild strawberry and marjoram. Recent ecological surveys of the whole site have revealed seven species of orchid In total, the site contains 283 plant species including 56 plant species that are indicative of good quality habitat. This is a significant number particularly since 50 is considered a good number for Sites of Special Scientific Interest. In 2006 floral surveys reveal several rare species including creeping willow and a nationally rare moss Grimmia orbicularis.

Ecological surveys also found twelve species of butterfly, including the Green Hairstreak and the largest population of grizzled skipper in Shropshire. Two target species, grizzled skipper and dingy

skipper, are still using the site. There are further Lepidoptera (butterfly and moth) surveys planned for 2010.

Public benefits

Public consultation and exhibitions were held in advance of the planning application. The history of successful restoration for wildlife at the site carried weight in winning over the views of the local community. There will be public access to the site with new footpaths linking the site to the surrounding footpath network. Access cannot be allowed to operational areas of the site, or to restored areas close by. However, with each completed phase of restoration, more areas are opened up to the local community. Schools and visiting academics can already access the site by appointment and an annual open day attracts a large number of visitors. Volunteers from the Shropshire Wildlife Trust have been active on site and are keen to return to carry out habitat management on a regular basis.

Llanymynech Rocks

This abandoned quarry is approximately 1.5km to the south of Llynclys and makes for an interesting comparison between natural regeneration and planned restoration. Llanymynech is part of the same Natural Area as nearby Llynclys and is similarly situated on Carboniferous limestone. The quarry itself was abandoned in stages with the last working taking place in the 1940s. Since its abandonment, the thin soils, which developed over the worked areas, have allowed an interesting limestone grassland mosaic to develop through natural regeneration. The site straddles the England/Wales border and is jointly managed by the respective Shropshire and Montgomeryshire Wildlife Trusts. Management of the site focuses on habitat conservation not restoration, concentrating on retaining the open limestone grassland areas and preventing scrub encroachment. For example, work by the both Wildlife Trusts focuses on managing the grassland scrub mosaic for the pearl-bordered fritillary. The site has good public access and is well used.