Merthyr Vale Tips

Tipping began on the top of Merthyr Mountain in 1913, when Merthyr Vale Colliery employed 3,575 men, making it the largest colliery in South Wales, and when all the space next to the colliery had been occupied by spoil heaps. By 1918, the first tip was eight meters high. So began tip number two further up the mountain, and later, in 1925, tip number three, when tip number two was also deemed too full for further tipping.

These disposal practices continued as ownership of the mine changed hands, from Nixon’s Navigation Coal Co. to Sir David Rees Llewellyn. In 1933, Llewellyn (Nixon) created a fourth tip on the hillside. In 1935, ownership of Merthyr Vale passed to Powell Duffryn Associated Collieries. After tip number four collapsed twice in 1944, Powell Duffryn began tip number five, which would eventually become the tallest tip at over fifty meters.

In 1947, upon nationalization of the coal industry, Merthyr Vale and its spoil heaps became property of the NCB. The NCB formed tip number six in 1956 and tip number seven two years later which, it transpired, was erected on a spring and was slowly absorbing gallons of water. By 1966, Merthyr Mountain supported seven huge spoil heaps that contained almost enough waste to fill the Great Pyramid of Giza. Snow settled on the peaks of the tips in the depths of winter. In the summer, children slid down their slopes on scraps of metal.

For the owners of the mines, this method of waste disposal was convenient and cheap. It required little investment and no monitoring or assessment. But the tips contained materials that had unstable chemical properties. They were loose and uncompacted. They had high contents of clay and silt and thus low permeability. Like a vast number of spoil tips in the region, the complex at Aberfan was erected on a porous sandstone slope. It contained washery shale, run-of-mine rubbish, screen belt pickings, boiler ash, and toxic tailings.

An inadequate drainage system caused perennial flooding so grave that, in 1959, the Merthyr Tydfil Borough Council created a subcommittee to deal expressly with this issue. In 1963, tip number seven collapsed not once but twice, causing more floods down at the village. Its toe advanced some six meters towards the site of Pantglas School. Having received complaints from the worried headmistress and several concerned mothers, Borough Engineer D.C.W Jones wrote to the NCB Area Chief Mechanical Engineer, setting out his fears that if the tips “were to move a very serious position would accrue.” These anxieties were downplayed by NCB authorities, who made promises – largely empty – to monitor and improve drainage.

And so, on 21 October 1966, the inevitable happened. The landslide in Aberfan was one of the worst mining disasters in British history. It was the largest affecting non-miners. A mass of slurry that would exceed the capacity of Royal Albert Hall ploughed through a farm and a row of cottages, descending upon Pantglas School. Almost half of its pupils were asphyxiated. They were the children and the grandchildren of the miners who, for the past fifty years, had slung waste from the mine to the top of the mountain.

Immediately after the tragedy, the government ordered an emergency inspection of tips across Britain. Geologists and engineers were dispatched to catalogue and measure the tips – for which, until then, no records existed – to evaluate their stability and to monitor their movements. The NCB also inspected the mines that they had leased to private companies. On October 24, Cledwyn Hughes, the Secretary of State for Wales, announced that all country borough and county district councils would arrange for checks of the tips that belonged to other entities.

Over the course of these inspections, it became clear that the NCB had little grasp of the number of tips that they owned and knew virtually nothing of their size, state, or location. The tip census commissioned by the NCB would go on for months after the disaster as the Board struggled to take responsibility for the tips under its ownership. Indeed, it still rejected this responsibility, and for many months refused to dismantle the tip complex even though it posed a risk to residents.

Eventually, in 1968, relenting to organized pressure from the villagers, the NCB and the British Government eventually agreed to remove the tips, on the proviso that local interests contribute to the cost of doing so. At their insistence, the bill was split three ways between the treasury, the NCB, and the Aberfan Disaster Fund. Charitable money given for the relief of the bereaved was spent instead on moving tonnes of coal waste. The murky details of this affair became public knowledge in 1996, once the embargo on the NCB files was lifted. In 1997, the £150,000 contribution made by the Aberfan Disaster Fund was returned to Aberfan under Tony Blair’s New Labour government. Ten years later, the interest value was also repaid by the Welsh Assembly, empowered by devolution.

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