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Colliery Spoil Biodiversity Initiative

Raising awareness of the important biodiversity value of colliery spoil sites.

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For more than a century, the landscape of the South Wales Valleys and the fortunes of the people who lived here were shaped by coal mining. The scars of heavy industry were everywhere and black tips of coal waste brooded ominously over the Valleys. But times have changed. Mining and heavy industry have gone, nature has acted and the landscape has been transformed.

Historically, wildlife suffered in the Valleys as coal mining fuelled Britain’s Industrial Revolution. Today, the spoil tips (and the locations of former colliery buildings) provide extraordinarily-rich and unique habitats for wildlife. Numerous species of birds, mammals, amphibians, reptiles, vascular plants, fungi, lichens and invertebrates now consider these places ‘home’. 

Many colliery spoil sites now support habitats and wildlife of considerable local, regional and national importance. Despite this, however, these sites are gravely misunderstood and under-appreciated. Each year, more and more of these sites are lost in South Wales and the wider United Kingdom. We cannot continue to stand-by and lose these precious sites. We must act now to ensure our remaining sites of biological, cultural and historical importance are protected. 

Cwm Coal Tips (c) Liam Olds.JPG
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Brief history of coal mining in South Wales

The pivotal role of coal mining in shaping the British way of life cannot be underestimated. For centuries, coal mining has been an essential part of British industry. At its peak, the British coal industry employed more than a million people, making it one of the country’s most important industries. Many regions were dependent upon it, including South Wales.

With its profusion of high quality coal, the South Wales Coalfield played a pivotal role in Britain’s Industrial Revolution. As Britain began to industrialise itself, more and more coal was needed to produce the steam power on which industry depended. This high demand for coal brought about a ‘boom’ in the South Wales coal industry. Attracted by the availability of work and better wages, people flocked to the South Wales Valleys from other parts of Wales, England, Ireland, Scotland and European countries.

The South Wales Coalfield coveres an expansive area, from St. Bride’s Bay in the west to Pontypool in the east. At its peak, the coal industry employed some 232,000 people in 620 coal mines across South Wales. In 1913, 57 million tons of coal came up from these mines – a fifth of the entire output of the United Kingdom. The effects of World War I and the post-war depression, however, brought about a decline in the industry. By 1936, 241 collieries had closed and the workforce had halved. Following a brief revival post-Second World War, the industry continued to decline throughout the second half of the 20th century. By the end of that century, just one deep mine remained in Wales. The coal industry, the most important industrial, social and political force in modern Wales, had all but vanished.

Nearly all the signs of this once thriving industry have been lost with colliery buildings demolished and shafts capped. What have remained are the heaps of coal waste (called colliery spoil tips) scattered along the Valleys sides and tops. Centuries of intense mining activity ultimately generated excessive quantities of waste, which was subsequently tipped in the landscape. These colliery spoil tips have become an iconic feature in the South Wales Valleys, an industrial and cultural legacy from Wales’ rich coal mining history.

Following the Aberfan Disaster in 1966, many colliery spoil tips were cleared amid fears of similar tragedies lying in wait. Those deemed stable remained, left undisturbed to naturally revegetate over time. Over many decades, these spoil tips have been colonised by a wide variety of species and habitats. Once black eye-sores in the landscape, many now support habitats and wildlife of considerable biodiversity value. Further information regarding the unique habitats and species found on these colliery spoil tips can be found in the ‘Biodiversity’ section of the website.

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Threatened habitats

The Aberfan Disaster of 1966, where the collapse of a spoil tip above the village killed 144 people, 116 of which were children, changed the fortunes of many of South Wales’ colliery spoil tips. Understandably, many spoil tips were cleared after this devastating event amid fears of similar tragedies lying-in-wait. Those tips deemed stable remained, left undisturbed to naturally revegetate over time. Over this period, many tips have developed interesting flora and fauna assemblages, with many now supporting habitats and wildlife of considerable biodiversity value.

Unfortunately, these sites are greatly overlooked and under-appreciated, despite their biodiversity and historical importance. Like many brownfield sites, they are regarded as ‘abandoned’ or ‘derelict’ waste land and receive little to no protection to safeguard their future. They face many threats including:

  • Development (housing and industrial)

  • Inappropriate reclamation or remediation

  • Inappropriate or absence of management

  • Planting with crop biofuels

  • Use of colliery spoil as aggregate for the construction industry

  • Removal due to perceived safety risks

  • Tree planting (broadleaf or coniferous)

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Why conserve colliery spoil sites?

As our countryside becomes steadily more degraded for wildlife, colliery spoil sites are becoming increasingly important places for wildlife. These sites are providing a must-needed refuge for species rapidly declining in our modern impoverished landscapes. By linking-up with traditional habitats, they also act as stepping-stones in the environment, allowing species to move freely across the landscape. Our 'natural' habitats would also be much more fragmented if not for colliery spoil.

But its not all about wildlife. Colliery spoil sites are also of geological, archaeological, historical, cultural, social and visual significance (see below). 

  • Geological – they provide access to fossils and minerals.

  • Archaeological – historic structures and remains can be found amongst the spoil.

  • Historical – they offer a visual reminder of our rich coal mining history that helped create and shape Great Britain. They also tell stories and family landscape links.

  • Cultural – colliery spoil is an important part of our cultural identity as South Walians.

  • Social – due to their often ‘open access’ and close proximity to settlements, they are readily used by local people for recreational activities, providing physical and mental health benefits. They often provide the only open-access areas for local people to get outdoors with nature.

  • Visual – they form visible features which are significant in the local landscape and have strong cultural resonance. They are used in regional and local interpretation (i.e. they tell a ‘landscape story’).

Colliery spoil sites tell the story of their prehistoric, geological, archaeological, historical, social and ecological past and the contribution to the lives of the valley communities past, present and future.

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A small amount of money can go a long way in helping us to raise the profile of colliery spoil sites and ensuring that these special sites, and their unique wildlife, persist for future generations to appreciate and enjoy. If you would like to support our work, donations are always gratefully received. Thank you!

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