I'm trying to discover a little more about the Granby 2 pit on Portland Road, Cotmanhay, Ilkeston. In particular, the deep shaft which appeared in the gardens of 5, 7 and 9 Portland Road in December 1978.
I've emailed the Coal Authority to see if there is an official report. I've looked at your excellent website and see that there was a tramway along Cotmanhay Road to Portland Road. Would Granby 2 Pit be a full, working pit or was it a subsidiary of Granby Pit? And why did the shaft open up (depth of 540 feet I think) in 1978? What causes mine shafts to open up after so many years?
Many questions - I'm hoping you have some answers or can point me in the right direction!
(Dr) Ann Featherstone
What Causes A Mine Shaft To Collapse After Many Years Of Being Closed?
The old shafts prior to NCB (1947) many before 1900 and no matter the depth were only filled with rubble or dirt tip material for say the top 10m to 25m (variable as to how much material the Company had on site, such as a small dirt tip from the shaft sinking strata, as hardly any dirt was sent out of the pit in those days of hand hewing...it was stowed underground behind the coal face in the goaf or gobbing.)
Wooden baulks, usually large timber joists would be fastened in to the sides of the shaft at that particular depth and other wooden planks etc. would be placed across these and the rubble filled on top. Over the years the rubble would subside leaving a shallow depression. Water from rain or other sources would seep down the shaft and eventually the timbers would rot and invariably collapse and the shaft walling (probably only one brick thick, mortared or un-mortared) and rubble would fall to the bottom of the shaft creating a large hole, generally larger than the size of the original shaft as the surface around the shaft would slump with the drag of the material as it fell. For example if an old shaft was 7 feet (2.13m) diameter it is possible to have a slumped hole at the top of 20 feet (6m), or more. Invariably acid loving plants such as nettles, some types of grass and dock leaves grow well on old weathered pit shale etc. One should be careful if this situation is found when in a well-known mining area. This can be very dangerous and over the years the NCB / British Coal, and since 1994 the Coal Authority, have made hundreds of coal shafts safe by finding them or in the case of a hole, proving that the hole is a coal mine shaft (not lead or other mineral) and then drilling down with a portable drill rig on a frame across the shaft for safety to see what depth the fill is and then completely filling the shaft if open with limestone chippings around 2" (5cm) diameter. It is possible for a hole twice as big to appear and maybe some clay and concrete used to stabilise it and then finally constructing a thick reinforced concrete cap over the top plus a safe distance around it. Prior to new rules under NCB in 1960/70s it was only necessary to make a mine shaft safe, e.g. putting a secure fence around the shaft.
New Granby or Granby No 2 was sunk by the Butterley Co in 1854 and was closed in 1887. There were several small shafts close together in that area. As outlined above this is where one shaft collapse or a large hole from some shallow mining in the area also due to a deep one collapsing which possibly may account for the hole covering No 5, 7 and 9 gardens on Portland Road in 1978? There are numerous known old shafts in the vicinity....are there any unknown ones?
New Granby, a colliery in its own right was sunk approximately 400 yards to the north of Old Granby, which would have closed before or when New Granby started. Of course invariably some or all of the best workforce would transfer but of course not all at the beginning, because the new mine would have to be developed and have new coal faces opened out, usually by skilled sinkers / heading men.
There was as you can see a name change as such. The first pit was called Granby but when the New Granby pit was sunk it was referred to as New Granby or Granby No 2, then the first Granby pit would be referred to as Old Granby to differentiate....mind boggling and confusing if you do not understand the reasoning.
A Pit Bank
A Pit Bank generally referred to the immediate area around the top or mouth of the shaft. A man called a Banksman was in charge of letting men in and out of the pit via the cage and operating the signals for such and sending materials into the pit in tubs or trams etc. Another Banksman was at the other shaft where coal was wound.
Fires smouldering on a pit heap or waste tip away from the pit top were caused by spontaneous combustion of the small pieces of coal that were discarded amongst the dirt, as only large pieces of coal were in demand. In the past these fires were allowed to burn because the result was red shale that was able to be sold for roadway foundations or driveways etc....a profitable byproduct but with an obnoxious smell and was very dangerous because of the production of carbon monoxide, a lethal gas created from the incomplete combustion of the coal over a long period.
Noises would be the puff puff and hissing of the small horse power whymsey winding engines, boiler fired and steam operated, some of which had chains on the engine, clanking no doubt. These chains were to assist the engine when raising coal up the shaft using hemp ropes.
Steam would be exhausted into the air. Other noises would have been when moving tubs or carts and possibly another engine for the gang line to a coal wharf nearby where coal would have been loaded into carts pulled by horses. That is until steam operated railway engines were used...again this could have added to the general noise....plus noise of voices shouting instructions when winding as that was the signalling system, then superseded by bells being sounded for each and every wind in the shaft for coal, men or materials.....a right mayhem at times I would imagine......plus of course general chit chat among the men....shouting!
Smells would be from the boiler fire grates and the ashes when raking out. The smouldering could be where the ashes, unburnt coal and clinker from the grates were tipped nearby and could have smouldered for quite some time before extinguishing, creating horrible foul smoke that no doubt drifted everywhere according to the wind. Of course no doubt other loads would have been tipped on the same site. Sometimes this residue was used to fill in ruts in cart tracks etc.
No account whatever was made to protect the people living nearby and I would imagine some living close by would have suffered most and indeed became ill......various chest diseases.
Hopefully this will answer most or all of your queries.
Wow! Thank you so much. I hadn't expected a response so full of information. You've answered a question that's been bothering me for donkey's years - how they filled in a mine shaft before the age of concrete! No wonder there have been so many collapses. I feel I've got a much better understanding of it now. And, as you've explained the history of the 2 Granby Collieries, it does make sense.
I'm attaching a copy of the 1887 (I think) OS map showing the New Granby Colliery. Portland Road ran through the middle of it. Ash Street was directly opposite Portland Road. I would think that numbers 5, 7 and 9 were located around numbers 168 and 170 on the map. I will know better, I think, when the Coal Authority sends me some information I've requested - as long as they don't want to charge me too much. Apparently there are some photographs, too.
With many thanks and best wishes,