My thanks to Neil Rowley for providing all the information in this post. This is an article that Neil wrote for a mining history society a few years ago. He has kindly shared ‘A Day in the Life of the Selby Complex’ from when he was Deputy Manager at Gascoigne Wood Mine.
A Day in the Life of the Selby Complex
Wednesday 29th May 1996
Gascoigne Wood Mine 1996
Cable Belt Inspection
Underside of ASL conveyor showing spillage
Map 1
Approximate Location of Working Faces and Main Conveyors in May 1996 (Surface/Underground correlation is by personal estimate and is for general interest only)
Area covered by Planning permission approximately 100 square miles
Introduction
Whilst clearing out my garage recently I found a folder of reports dating from 1996. At the time I was Deputy Manager at Gascoigne Wood Mine. The reports relate to the daily operations of the Selby Coalfield as seen from the control room at Gascoigne Wood.
I feel that these reports give good insight into the day to day working of a huge industrial complex which is now quickly receding into history.
The complex was made up of five producing mines with one common coal clearance system which brought the coal to the surface at Gascoigne Wood. Map 1 is adapted from an early brochure illustration and shows the general layout. Note that this early base map shows the East Coast Main Line running north/south through the centre of the mining area. Before coal production commenced, the railway was rerouted to the west of the production area to avoid subsidence issues, an example of the grand scale of the project. When I commenced my employment at the complex in 1980 I was told that it should have a life of 25 years, a surprisingly accurate prediction as final closure occurred in 2005.
All coal production from the complex at this time was from the Barnsley seam and the mining system employed was mainly retreating longwall.
The Reports
Each individual mine in the complex would have its own detailed daily reports but as Gascoigne Wood was the point at which all coal came to the surface to be prepared and dispatched, the GW reports needed to contain some basic information from each of the producing mines in order to enable fair allocation back to the individual mines of tons produced. Their operating budgets depended on it!
I chose a date of 29.5.1996 at random to illustrate the operation and sheer size of the complex. At the time the complex was owned by RJB Mining. Privatisation of the industry having taken place in late 1994.
Report 1 is the Daily Production Record for this date.
Safety was taken very seriously and reports generally commenced with this aspect.
It can be seen that there had been one minor accident at Gascoigne Wood during the day. A man had received an injury to the roof of his mouth from a sharp object. This somewhat unusual incident would have been discussed in some detail at the Manager’s morning meeting.
Then on to the production reports.
Wistow Mine had three producing longwall faces on this date. H92s was at the deeper end of the Wistow take and was of conventional length. H74s was shallower and hence shorter to control subsidence to within agreed limits. H134s was very short. Hence H92 could achieve 15.8 strips in the day, 74 managed 17.4 but 134 amassed 30 very short strips.
Riccall Mine had two faces. H478s was successfully mining an area to the south of Riccall village. H504s had just come into production a couple of weeks earlier. This may account for the lower than expected number of strips. It was located to the east of the shafts under Skipwith common.
Stillingfleet Mine had two faces both performing well. H302s was mining the area to the west of Escrick Brick Works. H266s was mining the area to the South of Naburn Lock.
Whitemoor Mine was operating two faces. H641s was to the south of the Whitemoor shaft pillar and H632s was north of North Duffield village. The low number of strips combined with the high ash content that we see from other reports suggests that the faces were in faulted areas and suffering from roof control problems. Depth below the surface of these workings was approximately 900m.
North Selby Mine was the deepest of the Selby mines and was producing from two faces. H906s was to the East of the shafts working at a depth of over 1000m. H856s was near Deighton village. Both seem to have been performing pretty well on this date. As a rough estimate I would say that the coal from H906s face had an underground journey of over 20Km through the conveyor system of the complex before it reached the surface at Gascoigne Wood.
Total mineral transported to the surface via the Gascoigne Wood conveyors on this day was well over 60,000 tonnes. This was pretty much a normal daily total for this period.
Total saleable coal leaving in the trains was 50,641 tonnes
1996 was the 5th successive year where annual saleable output exceeded 10 million tonnes. Profit for the complex in 1996 was reported to be £24.464 million.
Sadly the good times were coming to an end and production was to gradually fall away in the coming years as the better mining areas became worked out.
Report 1
Report 2 –Delay analysis for coal clearance systems 29.05.96
The two spine tunnels coming to the surface at Gascoigne Wood each contained a different type of conveyor.
The South Spine contained the ASL – named after Anderson Strathclyde Ltd, the designer and manufacturer. It was a 12.2 Km long steel cord conveyor running at high speed and capable of over 2000tph.
The North Spine contained the Cable Belt. The cable belt consisted of a very flat profile carrying surface resting on two steel cables. It was slightly earlier technology than the ASL and the flat profile gave rise to quite a lot of spillage, especially if one of the pulleys supporting the cables had a bearing failure, in which case the vibration caused the coal to be shaken off the conveyor. It normally ran at 1000tph but when demand for coal clearance was not so great, it was shut down and the ASL was used alone.
South Spine Delays
The first group of delays with the prefix ROM (Run of Mine) relate to stoppages of surface conveyors downstream of the ASL which in turn cause the stoppage of the main spine conveyors. CO7c was a common offender in this respect. It was the oversize conveyor feeding the barrel washer infeed stockpile and prone to large pieces of stone or timber causing misalignment or blocked chute.
Many of the other delays refer to belt torn protection being operated at various locations. B2 being Wistow bunker, B6 Stillingfleet Bunker etc. The belt torn probe was a wire stretched from side to side beneath the belt. If a piece of rubber was trailing from the belt then it would hit the wire and stop the conveyor. The conveyor was running at high speed so would take a little while to stop and the bunker operator would have some distance to walk to find the offending piece and cut it off.
Rollers were changed by a belt patrol team who did their inspection from a train travelling alongside the conveyor. The inspector was pretty much lying down in the vehicle so that he could see the underside of the conveyor.
Later in the evening problems start to occur with a steel cord coming out of the belt. This would need to have been chopped off and its position within the 24Km of belting noted for later vulcanized repair.
North Spine Delays
This conveyor was affected by the surface conveyor stoppages in the same way as the South.
The report shows several pulley changes and a rope off pulleys incident which were speedily dealt with. The numbers following the entry refer to the stand number on the conveyor structure. The last entry of “portal bubble trip” refers to a detector which was looking to ensure that the rubber belt was lying flat down on the cables. This consisted of a wire stretched at right angles above the carrying surface which would stop the conveyor if it was hit by anything. The trip wire had probably been hit by a large lump of coal on the conveyor and did not indicate a problem with the conveyor belting itself.
Report 2
Report 3 Gascoigne Wood Manager’s Morning Report
This is the summary of the day’s activities that landed on the Manager’s desk the following morning and a summary would be reported on to the Group Director.
The information in the first section predominantly comes from the Westerland feeders delivering onto the spine conveyors from each of the bunkers that the producing mines fed into. The feeders were wide slow flat conveyors of known bed depth and controllable speed which gave a pretty accurate record of tonnage throughput. Mounted over each feeder was a sensor picking up natural gamma radiation from the material passing beneath. Shale gives off more gamma than coal and so with careful calibration the percentage ash could be determined.
Coal from Whitemoor had to pass through Riccall Mine before it reached the spine conveyors and similarly North Selby coal had to pass through Stillingfleet. The ash monitors and weighers for these mines were located on the boundary between the mines and so were not under neutral control. This was often a source of much dispute between the mine managers, each seeking to gain maximum tons and hence income for their mine.
As a check on these ash measurements the GW Deputy Manager regularly visited the individual mines to do a rough face survey, measuring thickness of coal cut, amount of stone falling from the roof and thickness of floor dirt taken. This was a part of the job which I always found very interesting. These findings could then be used to adjust the ash content should it be necessary.
Belt weighers can vary greatly in accuracy so tonnage arriving at surface was adjusted to bring it in line with known weight dispatched over the certified weighers on the railway and changes in stock levels.
To reduce ash levels to those acceptable to the power stations a proportion of the coal needed to be washed and then re mixed back in. At this time there were two washing plants operating – The barrel washers which treated the larger material and the dense medium cyclone and spiral plant which treated the medium sizes. The undersize went straight through to form the basis of the blend. Tonnages into each process can be seen on the sheet.
The ash level to the power stations was running at 17.1% and we would be looking to bring this down a little by the quarter end. The customer paid on calorific value rather than per ton so a slightly high ash content would result in a lower return per ton. A factor critical to the customer was the handleability of the product. The last thing they wanted was coal sticking in the wagons and holding up the discharge of trains. Poor handleability was related to some extent by moisture content, which on this day was nicely in spec at 10.7, but could be more significantly affected by the MRF content.
MRF stands for Multi Roll Filtercake. This was produced by squeezing the moisture out of the finer material in the barrel washer plant. MRF had a good coal content but also contained fine clay particles which could cause handleability problems. It was obviously in everyone’s interest to send as little of this material to the tip as possible but blending it into the product had to be done cautiously to avoid sticky trains. A very fine balancing act.
A small amount of house coal was also being produced.
Three trains of stone left site to be disposed with domestic waste in Wakefield, the rest of the discard was disposed of in a very carefully constructed tip facility on site, with MRF cake enclosed in cells of coarser material. HAU stands for High Ash Undersize, of which 183,000 tons were on stock waiting to be blended back into the product when ash content from the mine reduced.
Report 3
Conclusion
This has been a very brief view of the activities taking place on this fairly typical day in 1996. The sheer size of the operation is clear to see with over 60,000 tonnes of mineral being brought to the surface and over 50,000 tonnes being dispatched to power stations throughout the country in a single day.
As with many mining projects, the geology of the area proved to be not as straightforward as anticipated in the early planning stages causing production to slow in later years. The basic design of the complex required high throughput to achieve cost efficiency and falling tonnages resulted in a rising cost per ton, leading to eventual closure in 2005.
Hopefully these reports give a glimpse of the coalfield operating at its designed output level, as it did throughout much of the 1990s, and give some indication of the tremendous engineering achievements and degree of human endeavour that made up this very bold project.
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Again, many thanks to Neil Rowley who was Deputy Manager at Gascoigne Wood Mine and who provided the information and memories in this post.
Selby Superpit 