Peter Squires visits the former Clipstone Colliery as it undergoes massive changes to repair the ravages of more than 70 years of coal mining.

Clipstone was sunk in 1922 by the Bolsover Colliery Company (BCC). The coal companies were nationalised in 1948, becoming the National Coal Board and under its modernisation plans changes came about in 1953, including sinking new shafts when the coal measure of the time was exhausted. Two new shafts were sunk to a depth of 920-metres (Blackpool Tower is only 160-metres high). The two headstocks are 64-metres high and once boasted of being the second highest in the world.

Coal came out of the mine and into the coal preparation plant where it was washed and graded by size before being transported via conveyor belt into large hoppers and into railway wagons, the trains bound for the coal-fired power stations of the nearby Trent Valley.

Welbeck Estates own the land under and around the colliery. A 100-year lease was granted to the BCC in 1934 and is owned by the Coal Authority until either 2034, or when mining operations cease.

After closure in 1993, and re-opening under RJB Mining a year later, Clipstone finally ceased production in April 2003 and the task began to remove the machinery, materials and other components from the pit top. The two shafts were filled in by contractors AMCO. In all 116,000 tonnes of non-sparking limestone were used to fill the shafts, plus pea gravel at the bottom with 30 metres of puddling clay at a depth of 280-metres.

Derbyshire company, JMC Engineering, is the representative of the Coal Authority and with the two shafts now filled it awarded a contract to East Midlands Demolition Limited to clear the site of all remaining buildings, such as the coal preparation plant, numerous surface buildings and slurry lagoons before putting the land back to 'tillageable' conditions as it was before the colliery was there.

Heavy plant began to arrive at Clipstone in September 2007.

Site forman, Martin Riley, explained how the plans were carried out. "Every building and structure was numbered on a plan view of the colliery. Not just brick, but steel girderwork, slate, wood, asbestos and other materials had to be dealt with before the excavators could move in," he said.

"These buildings still housed leftovers such as barrels of oil and other tooling and equipment, giving the demolition team a glimpse of the past."

Any asbestos (roofing, pipe lagging etc) had to be documented and a licenced removal firm brought in to safely remove and dispose of the materials.

Four slurry ponds had to be dealt with. These were where the water was pumped out of the mine workings would collect. Silt and sediment would be in this water and once settled, the water would finally be allowed to drain into the local River Maun, having monthly water tests to determine its contents. In total 80,000 tonnes of slurry were removed before East Midlands Demolition moved onto the site. East Midlands Demolition has worked in close liaison with the JMC Engineering in every stage of the project.

Around 20,000 tonnes of slurry were removed from these settling ponds (lagoons) of which a large percentage was proved to be coal dust. Although not much larger than particles of dust and grit, this was sold to Hargreaves before being taken to Immingham where it was mixed with imported coal and was burnt at Ferrybridge Power Station to power the same turbines that probably burnt Clipstones coal right up until the its closure.

Clipstone differed from most collieries in that the pit-head baths, canteen and medical centre were on the other side of the Edwinstowe to Mansfield main road. Safety was always the issue with the NCB and a tunnel was dug under the road from the pithead to the canteen. This also meant miners coming up the pit could get to the canteen faster, just in case the road was busy. These buildings were dismantled and the ground cleared by EMDL in 2005 and new housing now occupies the site.

Once the colliery buildings were cleared, the 360 degree excavators moved in. Most of the colliery surface was concrete. Stock piles were marked out by EMDL in which the various materials were tipped before being crushed, one for brick, one for concrete, steel etc, with steel girders positioned in concrete footings for strength.

As the colliery was changed in the mid- 1950s some of these buildings were removed and replaced. The acetylene torch would be put through the steel legs at ground level, so 50 years later the steel under surface level was still there and had to be dealt with.

The excavators would 'prove' the ground as they moved. They dug holes to a minimum depth of 1.5m (the agreed 'proofing' depth) and the colliery surface would soon look like a mass of hills and holes as the machinery moved onwards. Where the excavators found deeper structures such as foundations, these were dealt with. One such feature was an underground training gallery at a 9m depth.

Old water and waste pipes, electrical cabling and various mining needs were found within the 1.5m zone and all were graded into the stockpiles. Steel and copper cable would be sent for recycling as was plastic and rubber. As the stockpiles grew another plan had already been devised.

East Midlands Demolition brought in a 1412 Terex Pegson 1412 Trakpactor Crusher and Screen System to join the XR400 Terex Pegson already on site.

It is the first demolition company in England to use the 1412, although Germany has several in daily operation. Built in 2008 this beast weighs in at over 48,000 kg. It has a capacity of up to 550 tonnes per hour. It is fitted with the well-proven Hazemag AP-PH 1214/Q impactor driven directly through a 21 KPTO clutch by a Cat C13m-438hp engine.

All sorts of rubble are loaded in the hopper and this slowly moves along a vibrating table. The table has bars (resembling a larger version of a fire-grate) called double grizzly bars and any rubble less than 20mm (such as soil and small stones) pass through the bars onto a belt and are transported out of the machine onto a heap.

The remaining rubble passes into the Hazemag hammer box, where four hammers pound it into something called '6F2' or Type 1. Rubble sized from dust up to 70mm is named 6F2. Type 1 is rubble up to 50mm. As a second belt takes the 6F2 out from the crusher it passes under a powerful magnet.

This lifts out any steel and a third belt separates the steel onto a scrap pile ready for recycling. The lads at EMDL like to make their machines earn their keep, and the 1412 has already had new blow bars (the crushers) and a diesel tank! The blow bars can be adjusted for whatever size material is needed, 6F2, Type 1 or whatever.

With the former slurry ponds drained, they had to be filled in. Rubble and soil were brought in a Volvo A30D dumper before being levelled with the D5.

The Volvo A30D was constructed with two types of engine, the Volvo D9 and D10. The D9B engine boasting 341 hp net, coping easily with a payload of 28 tonnes and a speed of 53kph this articulated dumptruck doesn't hang around for long and kept both the D5 and Volvo EC240BLC 360-degree tracked excavator busy. It has a 74-degree tip angle, ensuring nothing is left in the back, kept on track with its Power-train transmission (six forward and two reverse gears).

The EC240 excavator is one of three Volvos on site (240, 210 and the larger 360BLC). Having an 8.27-litre Cummins C8.3C turbocharged six-cylinder engine giving out 180hp (gross) to a pair of variable displacement axial travel pumps, while the larger 360 was fitted with a Cummins M11-C six-cylinder engine, with 265hp (gross) to work with. This 10.8-litre engine is one of Cummins range of low-emission four-stroke diesels and has the auto-idle system, when the levers and pedals aren't in use, the engine drops to its idling speed. A choice of six or 6.45m booms were made available, three arms of 2.6, 3.1 or 3.9m and a ten-tonnes lift could be obtained (arm end without bucket) from the six-metre boom turning the excavator into a very useful crane.

Certified sub-soils were brought onto site from outside locations, such as the widening of the M1 motorway in Nottinghamshire. This was used to backfill the voids left by deeper foundations under Environment Agency licence.

Other screeners were being fed by the excavators, including a Terex Finlay 883 reclaimer, designed to work as an aggregate screener after a primary crusher or on it's own as a frontline screening machine. A 96hp Deutz BF4M 2012 water-cooled engine works this machine, the seven cu.m. capacity hopper grading its load onto a choice of three conveyors (fines, middle and oversize).

Now part of the Terex group, Finlay are represented in over 80 countries worldwide. To facilitate this expansion, Finlay have now centralised all its manufacturing to a 400,000 square foot factory in Omagh, Northern Ireland.

The second (smaller) Terex Pegson XR400 crusher-screener with its Caterpillar C9, 8.8-litre 230hp engine was temporarily out of action. 2008 was one of the wettest years on record and the 45,tonne machine had 'sunk' down to the top of its tracks in the ground after a weekend of heavy rain. As it was being driven out a large lump of concrete jammed between the tracks and damaged the cross-members that supported the main conveyor belt rollers.

This was being sorted out by Phil Ashby of Ashby Plant & Commercials along with Gavin Cotton. "We repair a lot of the East Midlands Demolition plant and have got our hands full with this Above: Keeping good order Is East Midlands Demolition's site foreman, Martin Riley. one," said Phil. "There's quite a bit of damage but it'11 get sorted. The frames inside the tracks are only thin material (about 6mm) and won't take much of a hiding. You'd think they would be constructed of thicker steel capable of taking a knock or two!"

On the occasion of The Coal Authority's Annual Public Meeting in Cardiff in 2008. Clipstone Colliery Demolition and Site Restoration, received a special award for outstanding personal contribution to the environment in 2008.

This award was presented for the exceptional way that East Midlands Demolition had managed the site, reclaiming and recycling some 96 per cent of all materials arising from the demolition and restoration whilst at the same time providing protection to local residents and sensitive environmental areas during the intense demolition process.

Only the two German-designed headstocks, along with the powerhouse and winding engine houses, remain at Clipstone as a visible reminder of the industry they served. Vt While many (including former miners and 8 residents of Clipstone) feel they should be pulled down, others want to preserve them, so by the time East Midlands Demolition have finished its contract and the area resembles the fields that were present 100 years ago, the future of the headstocks is (at present) uncertain.

Health & Safety always comes first and although the headstocks will remain in the memory of the workers, residents and passing motorists, perhaps it would be for the best if they, like many other collieries throughout Britain were brought down and put to rest, saving the highly expensive costs involved in their upkeep and the cost of security, not to mention the ongoing possibility of accidents - 64 metres is a long way to fall.

Thanks go to Richard Fairweather for supplying 1950s black and white photographs of Clipstone. If it wasn't for Richard's quick thinking these photographs would have been lost forever.