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Greenside Mine, Cumbria by Ian Miller -------------------------------------------------------------------------------- Lead mines were often in mountainous districts, as veins can be detected more readily where the solid rocks are either totally denuded or are very near the surface. The lead ore was worked by a series of horizontal tunnels, or levels, driven into the vein. Where the ore continued downwards below the lowest level, a vertical shaft was sometimes mined to allow more levels to be excavated. Once extracted, the non-metallic minerals such as calcite and barite, known as ‘gangue’, had to be separated out before the ore could be melted in a furnace. This operation was called ‘dressing the ore’, and involved breaking the mineral rock into small pieces to allow the galena to be selected. This process was entirely manual until the late 18th century, when mechanisation was introduced. The melting process was known as smelting, and the furnace was referred to as a smelt mill. Whilst only relatively small quantities of lead were used during the Middle Ages, the increase in the building of great houses during the 16th century, for instance, resulted in a demand for vast quantities of lead for roofs, gutters and down pipes, water storage cisterns, and window kames. As a consequence of this increased demand, a period of intensive prospecting was initiated by the Company of Mines Royal, which was chartered in 1568. This joint-stock company was primarily concerned with copper mining and smelting, but its charter also empowered it to mine lead in certain counties, including Yorkshire and the modern county of Cumbria. The Company prospected for lead in the Lake District, but failed to discover the Greenside vein that occurs in the high fells above Glenridding, near Ullswater. This was to become the site of the largest lead mine in the Lake District, and one of the most valuable mines in the north of England. On account of the historical significance of the mine, it has been designated as a Scheduled Monument. Intensive operations commenced at Greenside in 1825, when the Greenside Mining Company was formed. This mining venture rapidly became very profitable, having sustained a tenfold increase in value between 1827 and 1837. The profits were invested back into the mine; by 1829 a smelt mill had been constructed at the site, which meant that the slow (and expensive) journey to Keswick was no longer necessary. The smelt mill was expanded and improved during the 1830s to include a silver refinery to extract silver from the lead; by 1839, the company was selling all its silver output to the Bank of England. Lead mining was a particularly prosperous industry during the mid-19th century, reflecting the ever-increasing demand for lead; it was required as a raw material for glass-making, pottery glazes, enamelling, as a paste for gaskets in boilers and pipework, and for paint. It was during this period that Greenside became the first lead mine in the region to boast an annual output of well over 1,000 tons. Amongst the numerous modifications to the mine at this time was the construction of an extended flue, over one mile long, that was built from the smelt mill. This took poisonous fumes away from the site, but also acted as a condenser to re-crystallise the lead held in a gaseous form. Every now and again, a worker was sent into the flue to scrape the lead crystals from the walls and return them to the smelt mill. Another significant development of the mid-19th century was the introduction of round buddles, which were used to wash the fine sands and slimes. Two round buddles were installed initially during 1855, the first to be used in the North West, and by 1867 ten round buddles were in operation. These improvements not only had the effect of increasing the amount of lead which could be extracted, but also reduced the level of pollution in the river.
A major addition to the site during the mid-19th century was the Low Mill dressing complex, where the ore was crushed and washed by water-powered machinery. This demanded considerable amounts of water, and an elaborate system of leats was constructed to channel the water from one process to the next. The most remarkable use of water at Greenside, however, was the pioneering use of hydro-electricity. The use of water turbines to generate electricity was introduced to the mine during the 1890s, and soon became its main source of power; in 1891, electric haulage was first used, and in 1893 an electric locomotive was introduced in the main underground haulage level to carry ore from the mine to the dressing plant. The use of electric power for winding and pumping not only increased the efficiency of mining, but also allowed deeper shafts and more levels to be mined, thereby increasing the output of lead. The innovative use of electricity was one of the reasons for Greenside mine surviving the depression in lead prices between 1875 and 1885, when the value of lead halved. This depression caused many of the smaller lead mining concerns in the north of England to close, such as those in the Pennine valleys of Swaledale and Wensleydale. During the early 1920s, lead production from the mine rose sharply, with a corresponding increase in the demand for electrical power. The company decided to construct a second hydro-electric power station, and a new building was duly erected in 1924. The water was used to drive a Gilkes’s Turgo Impulse turbine, which had an 18” wheel and could generate 186hp at 1000 rpm. The Greenside Mining Company continued to operate the site until 1936, when insolvency resulted in the company being liquidated. The mine was taken over by the Basinghall Mining Syndicate, who modernised the dressing operation. These improvements produced large amounts of industrial tailing waste material, which were mixed with water to form a slurry. After 1942, this material was pumped to the top of a specially designed tailings dam, and the water drained out through wooden sumps constructed within the dam, leaving a large spoil heap of fine tailings. A second tailings dam was constructed above the Low Mill dressing complex in 1954, and ultimately buried many of the abandoned features of the Low Mill complex. The Basinghall Mining Syndicate went into liquidation in 1954, although a new company called Greenside Mines Limited was set up to run the mine. This new company was to be short-lived, however, and in 1959 a decision was made to draw out the remaining ore and close the mine. In the latter stage of the mine’s life, for a short period, Greenside Mine came under the control of the UK Atomic Weapons Research Establishment, and was used to test a theory that an underground nuclear test explosion could be made undetectable by its seismic signal. The experiment was known as Operation Orpheus, and involved two test explosions at Greenside Mine. The success of Operation Orpheus led to the shelving of a test ban treaty, then being negotiated between the West and the Soviet Union, since the test had demonstrated that underground nuclear tests could not easily be policed by the opposing side. In recent years, the tailings dam upslope of Low Mill suffered severe, but localised, failure resulting in substantial land-slippage. To prevent risk of further failure, an engineering programme was proposed in order to stabilise the dam. A requirement of the works was that a programme of archaeological recording be undertaken. During 2002, OA North was commissioned by the Lake District National Park Authority to undertake the excavation and survey of the areas of the site that were to be affected by the development. This included an investigation of the 1924 hydro-electric power house, which had been reduced to a pile of rubble as a result of demolition during the 1980s. The rubble comprised concrete blocks, probably produced at the mine; the manufacture of concrete building blocks was undertaken at Greenside during the early 1920s as a sideline business, using the waste sand and gravel from the mill. |
The first miners to exploit this rich source of lead were reputedly a party of Dutch adventurers during the late 17th century. The earliest workings at Greenside were near the summit of a spur of the Helvellyn mountain range. The galena ore mined there yielded 80 per cent of lead and 12 per cent of silver per ton. Once extracted and dressed, the ore was carried by packhorse for some 12km over the mountains towards Keswick for smelting and de-silverisation. 
The success of the mine during the mid-19th century is reflected by the expansion of Glenridding village. By 1849, some 300 people were employed at the mine and, during the 1850s, the Company began to build cottages in Glenridding to house the miners. By the end of the decade, some 52 houses had been built, forming a distinct community of miners.