Daw Mill Colliery... A barren wasteland nestled between an active railway, and a minor road. To those who don't know, all that remains are foundations, a ruined house and abandoned railway sidings, to those that like to squeeze through tiny holes, there's a few hidden gems remaining beneath the surface... Only took 3 visits for me to crack this nut, thank you to @alex17595 for some insight into what I actually found 
The Colliery can be seen fully intact Here and Here
Background
Daw Mill was one of the first new collieries to be opened by the NCB, and the only one to be opened in the Warwickshire Coalfield. It served as a natural extension to the nearby Kingsbury (closed in 1968) and Dexter Collieries.
Work to sink the first shaft began in 1956, with it originally being intended to ease the ventilation problems in the Dexter Colliery workings. Late in 1958 when the shaft had reached around a third of it's final depth, it was decided that Daw Mill would be established as a new colliery, handling the coal from Dexter along with administration and preparation being centralised at Daw Mill. The shaft was completed in 1959 to a depth of 1,770 feet.
Dexter was originally worked as part of Kingsbury Colliery, with a ventilation roadway linking them, and coal transported via an above ground tramway. Upon the opening of Daw Mill, the ventilation roadway was sealed, and coal winding ceased. The Shaft remained operational however as Daw Mill utilised it for Man Riding.
This remained the case until the second shaft at Daw Mill was sunk, work on which began in 1969, with it being completed in 1971 to a similar depth as the first. However, Dexter Colliery still remained open for man riding after this, serving the Birch Coppice Colliery until this closed in 1986, making the shaft at Dexter redundant.
By the late 70s, coal output was consistently meeting the winding capacity of the shafts, so work to drive a drift began. This was complete by 1983, resulting in production rates increasing significantly. The drift was fitted out with a conveyor which linked to the truck conveyors in the workings, negating the need for time consuming winding via the shafts.
Daw Mill ended up as the last working colliery in the Warwickshire Coalfield, a coalfield which once boasted 20 operating collieries. Coal was mined from the Warwickshire Thick Seam, which was five metres in depth around their take. Daw Mill broke the annual production record that had been held by the Selby super mine for 13 years in 2008 when it produced 3.25 million tonnes of coal.
The Disaster
On the 22nd of February 2013, a major fire broke out 1,770 feet (a later UK Coal statement suggests a depth of 2,427 feet) underground, with it being described as the worst underground fire in the UK in 30 years. It started around 15:30 at the tailgate of the 32s face, 8km from the shaft bottom.
92 miners were immediately evacuated, with 14 remaining underground to battle the blaze. They tried in vain for 4 hours to contain it, but with the situation only worsening, mine management had to concede defeat and abandon the pit, with the remaining miners safely evacuated to the surface by 21:00. Ventilation was shut off by 22:45 in an attempt to starve the fire of oxygen.
The fire continued to burn, with it still not being extinguished when closure was announced. A BBC article dated 15th May 2013 announced that the fire had finally been extinguished by starving the mine of its Oxygen supply.
It was estimated that remedial works to reopen the mine would take 3-6 months, so of course given that the UK coal mining industry was on its last legs at this time, there was no chance of this happening, so the closure of the colliery was announced by UK Coal on the 7th March, with all 650 of the staff being made redundant.
Even if the colliery had stayed open, it would have been forced to close in short order due to HS2 passing near the site, an issue which was highlighted in 2012 by the Coal Authority.
The Route to Redevelopment
Ownership of the site was quickly transferred to Harworth Estates, a redevelopment firm, with this taking place after UK Coal went into insolvency in July 2013. They submitted plans to turn the site into a business park, but these were withdrawn in October 2014 after significant local opposition from in the area.
A revised plan was submitted a year later which also gained the support of the Highways Department of Warwickshire Council, but again was met with stiff opposition. The application exhausted it's appeals in 2018, with the court of appeal ruling that the land must be restored to the Green Belt... Probably why it's been left as a concrete wasteland, doubt Harworth want to pay when they get nothing out of it.
The Fires Continue
Unfortunately, due to the type of coal in the Warwickshire Thick Seam and the sheer volume of it remaining underground at Daw Mill (an estimated 56 million tonnes), fires continued to break out within the mine, as the coal is liable to spontaneous combustion. This was the root cause of the original fire as well. This issue wouldn't be solved until the mine was completely isolated from the surface, with the shafts and drift blocked off to prevent any oxygen from reaching the flames.
Another major fire broke out in October as work was beginning on infilling the shafts, with the only way to extinguish it being to progress on works to seal the mine. The initial layer of limestone and the first clay plug in each shaft was deemed sufficient to achieve this. The fire was discovered on the 28th October when the Drift Terminal building was opened up for closure works. It was found that a colourless smoke was emanating from the drift entrance, so air sampling was undertaken, finding elevated levels of Carbon Monoxide. This indicated that there had been a further spontaneous combustion event, likely at the pit bottom.
Capping the Shafts
Filling the shafts was no easy task, with specialist firm ECS Engineering Services being brought in to assist. A bespoke cover was designed to cover Shaft No.1 in order to allow work to safely be carried out, with it having a 5:1 safety factor and resilience enough to last for 25 years should there be any reason for work to stop for a long period.
The cables and counterweights in the shaft weighed 200 tons, and the cover allowed these to be secured in place without the Headgear supporting them. This allowed the cables above the cover to be cut, facilitating the removal of the Headgear whilst leaving the cabling in place down the shaft to act as reinforcing for the concrete infill. The cover also prevented movement which had the potential to create voids as the concrete was poured. Shaft No. 2 didn't have this problem, as it was built using a rail system in place of traditional cabling.
Both the shafts were completely infilled with a mixture of limestone, concrete, aggregate and a pair of clay plugs. Shaft No.1 was filled as follows; 5,000+ tonnes of limestone, to a depth of 50m, 10m of concrete, 1,400 tonnes of limestone, 1,200 tonnes of clay to form the first plug, 3,400 tonnes of aggregate, 1,200 tonnes of clay for the second plug, then 27,500 tonnes of aggregate to fill the shaft to the surface.
Shaft No.2 was filled with 6,000+ tonnes of limestone, followed by 1,000 tonnes of clay to form the first clay plug, 2,300 tonnes of aggregate then another 1,000 tonnes of clay to form the second plug, with a further 22,500 tonnes of additional aggregate to reach the top of the shaft.
Most of the aggregate for the infilling was material from the demolition of the rest of the site. Presumably the work to completely infill the shafts wasn't complete until the rest of the site was in an advanced state of demolition. The clay plugs served to stop any oxygen getting down the shafts, and to prevent mine water from mixing with the water in the local aquifer. The Drift was also sealed up in order to prevent any oxygen from reaching the fire.
Blocking the Drift
Due to gas and smoke from the October fire, it wasn't safe for miners to head into the drift in order to seal it. Work was instead done from a field 160m above by a company called Drilcorp, using 9 boreholes in a V formation. Tons of concrete and low slump cement were poured down 6 of these boreholes, with the 3 holes on the centerline being used for CCTV cameras to view progress and make sure everything was sealed properly.
Site Demolition
Demolition of the surface structures was carried out by JMC Engineering (UK) with an estimated cost of £0.8m, with a duration of 40 weeks, with initial works beginning in autumn 2013. The crews were tasked with asbestos removal as identified in a prior asbestos report, and demolishing everything to the foundations, Except for the south western section of the Bath House which had some hand separation works carried out, everything was demolished with 360° excavators.
Going from the reports posted on here at the time, presumably work to raze all the surface buildings to the ground didn't start in earnest until the spring of 2014. Harworth promised to donate the pit wheels to four local organisations, with the first of these donations taking place in April 2015. Two half wheels remain in situ on the colliery site as well.
The Current Situation
In 2018 an attempt was made by person's unknown to gain access to the drift via the surface portal. A fire was set on timbers that formed part of the shuttering when the concrete trespass wall had been built. This attempt proved to be successful, due to the fire igniting an explosive mix of methane and oxygen in the drift. The force of the explosion forced the 20 tonne seal back 1.9m. Mine rescuers responded to the incident, heading 220m down the drift to ensure nobody had been caught up in the explosion.
In May 2022, Harworth Estates were issued with an enforcement notice to comply with their legal obligations to restore the site to the Green Belt as no attempt has been made to restore the site, and Harworth haven't put forward any proposals. As of my visit third visit, there are still no signs of anything taking place. On to the explore...
The Explore
Visit Number 1
Visited as a final stop en route home from an Urbex trip, I was pretty knackered and wasn't expecting much, so didn't really bother looking that hard, which was a mistake...
Made my way past the settling tanks and was greeted with an expanse of concrete and not much else... There's some decent Graff adorning some of it, which makes things slightly less bland, and the sidings off the main line remain in situ. I'm not sure if they have been severed, I never bothered walking to the end as the main line is active.
Graff -
Controls for the tank pumps, probably -
Settling Tank Pump -
Possibly a Head Shunt? Leads nowhere, and is the opposite end of the site to the mainline junction -
Had a walk around and found a couple of open manholes, and some gaps in the rubble filled access points to the conveyor tunnels big enough to shove a camera and torch through, but that's about it. Could see that there was something down one of them, but my hole of choice was far too small to squeeze through.
Climbed up the infilled access for the Rapid Loader conveyor (RLC), sent the drone around and called it a day.
Foundations -
Pit Wheels -
Daw Mill in 2010 -
During Demolition -
The View Today -
I completely forgot about the house, and I also managed to lose a pair of sunglasses (bad habit that, always seems to be at collieries too). Little did I know the prize was directly beneath my feet and all I needed to do was look a little harder...
Visit Number 2
This was a flying visit, again on the return leg from an Urbex trip. Having rechecked the report Here, I knew what I was missing and just needed to somehow find it. Used the same access as before and started checking every possible access point to get beneath the surface, including one of the manholes from visit 1 which I failed to find, presumably as it had been covered.
The manhole down into what I'm presuming is a drain/culvert was open with a lovely long ladder down, so I was wondering if it was relevant. However, not fancying crawling around underground whilst being solo, especially with a good flow of water, I pinned it and moved on. Climbed the back of the RLC access for a vantage point over the whole site, whilst entertaining a vague notion of maybe locating those sunglasses...Yet again, I didn't realise I had overlooked the way in right beneath my feet...
Checked an access point I didn't see last time, had a hole that was potentially big enough to squeeze through, albeit with a lot of contorting. Not wanting to risk getting stuck/trapped, I pinned it and moved on. This visit ended up being mostly a recce for the successful third visit.
Rechecked a couple of access points near the shaft, but found the holes to still be too small to get through. Made a mental note to recheck them on the next visit and moved on.
I nailed the house on this visit, although given it's sketchy condition, I didn't bother going inside, presumably there's nothing of interest in there, all the lovely documentation left behind is in the outbuildings, which made for a wonderful find, and made the second visit at least remotely worthwhile.
Data Protection
-
Loading Authorisation Slip -
Explosives Tracking Sheet -
Invoice -
Visit Number 3
Went with company this time, determined to nail everything. Didn't bother with the drain, although it was still open albeit covered, somebody had also tied a rope to it. Tried the hole I pinned, but couldn't contort myself around the debris to get down the tunnel and my friend took one look and said nope.
I'm curious as to what is down there though, as it's situated roughly above the RLC chamber. We could hear voices down there, turns out there was another group of explorers in the RLC chamber.
Does anybody know what could be down there? It's on a higher level, so the top of the hoppers would be my best guess.
Having failed to get in, my friend suggested climbing up the rubble heap to the top of the RLC access. Lo and behold, hiding just out of sight from the outside is a small hole! If only I had looked harder on my earlier two visits...
Conveyor -
Hoppers -
Control Panel -
Flooding -
Emergency Stop -
Motor -
Having covered that section we made our way over towards the shafts, and it appears somebody had been digging at the rubble, because there was a small enough hole to squeeze inside another conveyor chamber, albeit a much smaller one.
Switchgear -
Conveyor -
Hopper -
If you've read this far, congratulations, you've just read a massive report on a couple of conveyors...
Thanks for looking
The Colliery can be seen fully intact Here and Here
Background
Daw Mill was one of the first new collieries to be opened by the NCB, and the only one to be opened in the Warwickshire Coalfield. It served as a natural extension to the nearby Kingsbury (closed in 1968) and Dexter Collieries.
Work to sink the first shaft began in 1956, with it originally being intended to ease the ventilation problems in the Dexter Colliery workings. Late in 1958 when the shaft had reached around a third of it's final depth, it was decided that Daw Mill would be established as a new colliery, handling the coal from Dexter along with administration and preparation being centralised at Daw Mill. The shaft was completed in 1959 to a depth of 1,770 feet.
Dexter was originally worked as part of Kingsbury Colliery, with a ventilation roadway linking them, and coal transported via an above ground tramway. Upon the opening of Daw Mill, the ventilation roadway was sealed, and coal winding ceased. The Shaft remained operational however as Daw Mill utilised it for Man Riding.
This remained the case until the second shaft at Daw Mill was sunk, work on which began in 1969, with it being completed in 1971 to a similar depth as the first. However, Dexter Colliery still remained open for man riding after this, serving the Birch Coppice Colliery until this closed in 1986, making the shaft at Dexter redundant.
By the late 70s, coal output was consistently meeting the winding capacity of the shafts, so work to drive a drift began. This was complete by 1983, resulting in production rates increasing significantly. The drift was fitted out with a conveyor which linked to the truck conveyors in the workings, negating the need for time consuming winding via the shafts.
Daw Mill ended up as the last working colliery in the Warwickshire Coalfield, a coalfield which once boasted 20 operating collieries. Coal was mined from the Warwickshire Thick Seam, which was five metres in depth around their take. Daw Mill broke the annual production record that had been held by the Selby super mine for 13 years in 2008 when it produced 3.25 million tonnes of coal.
The Disaster
On the 22nd of February 2013, a major fire broke out 1,770 feet (a later UK Coal statement suggests a depth of 2,427 feet) underground, with it being described as the worst underground fire in the UK in 30 years. It started around 15:30 at the tailgate of the 32s face, 8km from the shaft bottom.
92 miners were immediately evacuated, with 14 remaining underground to battle the blaze. They tried in vain for 4 hours to contain it, but with the situation only worsening, mine management had to concede defeat and abandon the pit, with the remaining miners safely evacuated to the surface by 21:00. Ventilation was shut off by 22:45 in an attempt to starve the fire of oxygen.
The fire continued to burn, with it still not being extinguished when closure was announced. A BBC article dated 15th May 2013 announced that the fire had finally been extinguished by starving the mine of its Oxygen supply.
It was estimated that remedial works to reopen the mine would take 3-6 months, so of course given that the UK coal mining industry was on its last legs at this time, there was no chance of this happening, so the closure of the colliery was announced by UK Coal on the 7th March, with all 650 of the staff being made redundant.
Even if the colliery had stayed open, it would have been forced to close in short order due to HS2 passing near the site, an issue which was highlighted in 2012 by the Coal Authority.
The Route to Redevelopment
Ownership of the site was quickly transferred to Harworth Estates, a redevelopment firm, with this taking place after UK Coal went into insolvency in July 2013. They submitted plans to turn the site into a business park, but these were withdrawn in October 2014 after significant local opposition from in the area.
A revised plan was submitted a year later which also gained the support of the Highways Department of Warwickshire Council, but again was met with stiff opposition. The application exhausted it's appeals in 2018, with the court of appeal ruling that the land must be restored to the Green Belt... Probably why it's been left as a concrete wasteland, doubt Harworth want to pay when they get nothing out of it.
The Fires Continue
Unfortunately, due to the type of coal in the Warwickshire Thick Seam and the sheer volume of it remaining underground at Daw Mill (an estimated 56 million tonnes), fires continued to break out within the mine, as the coal is liable to spontaneous combustion. This was the root cause of the original fire as well. This issue wouldn't be solved until the mine was completely isolated from the surface, with the shafts and drift blocked off to prevent any oxygen from reaching the flames.
Another major fire broke out in October as work was beginning on infilling the shafts, with the only way to extinguish it being to progress on works to seal the mine. The initial layer of limestone and the first clay plug in each shaft was deemed sufficient to achieve this. The fire was discovered on the 28th October when the Drift Terminal building was opened up for closure works. It was found that a colourless smoke was emanating from the drift entrance, so air sampling was undertaken, finding elevated levels of Carbon Monoxide. This indicated that there had been a further spontaneous combustion event, likely at the pit bottom.
Capping the Shafts
Filling the shafts was no easy task, with specialist firm ECS Engineering Services being brought in to assist. A bespoke cover was designed to cover Shaft No.1 in order to allow work to safely be carried out, with it having a 5:1 safety factor and resilience enough to last for 25 years should there be any reason for work to stop for a long period.
The cables and counterweights in the shaft weighed 200 tons, and the cover allowed these to be secured in place without the Headgear supporting them. This allowed the cables above the cover to be cut, facilitating the removal of the Headgear whilst leaving the cabling in place down the shaft to act as reinforcing for the concrete infill. The cover also prevented movement which had the potential to create voids as the concrete was poured. Shaft No. 2 didn't have this problem, as it was built using a rail system in place of traditional cabling.
Both the shafts were completely infilled with a mixture of limestone, concrete, aggregate and a pair of clay plugs. Shaft No.1 was filled as follows; 5,000+ tonnes of limestone, to a depth of 50m, 10m of concrete, 1,400 tonnes of limestone, 1,200 tonnes of clay to form the first plug, 3,400 tonnes of aggregate, 1,200 tonnes of clay for the second plug, then 27,500 tonnes of aggregate to fill the shaft to the surface.
Shaft No.2 was filled with 6,000+ tonnes of limestone, followed by 1,000 tonnes of clay to form the first clay plug, 2,300 tonnes of aggregate then another 1,000 tonnes of clay to form the second plug, with a further 22,500 tonnes of additional aggregate to reach the top of the shaft.
Most of the aggregate for the infilling was material from the demolition of the rest of the site. Presumably the work to completely infill the shafts wasn't complete until the rest of the site was in an advanced state of demolition. The clay plugs served to stop any oxygen getting down the shafts, and to prevent mine water from mixing with the water in the local aquifer. The Drift was also sealed up in order to prevent any oxygen from reaching the fire.
Blocking the Drift
Due to gas and smoke from the October fire, it wasn't safe for miners to head into the drift in order to seal it. Work was instead done from a field 160m above by a company called Drilcorp, using 9 boreholes in a V formation. Tons of concrete and low slump cement were poured down 6 of these boreholes, with the 3 holes on the centerline being used for CCTV cameras to view progress and make sure everything was sealed properly.
Site Demolition
Demolition of the surface structures was carried out by JMC Engineering (UK) with an estimated cost of £0.8m, with a duration of 40 weeks, with initial works beginning in autumn 2013. The crews were tasked with asbestos removal as identified in a prior asbestos report, and demolishing everything to the foundations, Except for the south western section of the Bath House which had some hand separation works carried out, everything was demolished with 360° excavators.
Going from the reports posted on here at the time, presumably work to raze all the surface buildings to the ground didn't start in earnest until the spring of 2014. Harworth promised to donate the pit wheels to four local organisations, with the first of these donations taking place in April 2015. Two half wheels remain in situ on the colliery site as well.
The Current Situation
In 2018 an attempt was made by person's unknown to gain access to the drift via the surface portal. A fire was set on timbers that formed part of the shuttering when the concrete trespass wall had been built. This attempt proved to be successful, due to the fire igniting an explosive mix of methane and oxygen in the drift. The force of the explosion forced the 20 tonne seal back 1.9m. Mine rescuers responded to the incident, heading 220m down the drift to ensure nobody had been caught up in the explosion.
In May 2022, Harworth Estates were issued with an enforcement notice to comply with their legal obligations to restore the site to the Green Belt as no attempt has been made to restore the site, and Harworth haven't put forward any proposals. As of my visit third visit, there are still no signs of anything taking place. On to the explore...
The Explore
Visit Number 1
Visited as a final stop en route home from an Urbex trip, I was pretty knackered and wasn't expecting much, so didn't really bother looking that hard, which was a mistake...
Made my way past the settling tanks and was greeted with an expanse of concrete and not much else... There's some decent Graff adorning some of it, which makes things slightly less bland, and the sidings off the main line remain in situ. I'm not sure if they have been severed, I never bothered walking to the end as the main line is active.
Graff -
Controls for the tank pumps, probably -
Settling Tank Pump -
Possibly a Head Shunt? Leads nowhere, and is the opposite end of the site to the mainline junction -
Had a walk around and found a couple of open manholes, and some gaps in the rubble filled access points to the conveyor tunnels big enough to shove a camera and torch through, but that's about it. Could see that there was something down one of them, but my hole of choice was far too small to squeeze through.
Climbed up the infilled access for the Rapid Loader conveyor (RLC), sent the drone around and called it a day.
Foundations -
Pit Wheels -
Daw Mill in 2010 -
During Demolition -
The View Today -
I completely forgot about the house, and I also managed to lose a pair of sunglasses (bad habit that, always seems to be at collieries too). Little did I know the prize was directly beneath my feet and all I needed to do was look a little harder...
Visit Number 2
This was a flying visit, again on the return leg from an Urbex trip. Having rechecked the report Here, I knew what I was missing and just needed to somehow find it. Used the same access as before and started checking every possible access point to get beneath the surface, including one of the manholes from visit 1 which I failed to find, presumably as it had been covered.
The manhole down into what I'm presuming is a drain/culvert was open with a lovely long ladder down, so I was wondering if it was relevant. However, not fancying crawling around underground whilst being solo, especially with a good flow of water, I pinned it and moved on. Climbed the back of the RLC access for a vantage point over the whole site, whilst entertaining a vague notion of maybe locating those sunglasses...Yet again, I didn't realise I had overlooked the way in right beneath my feet...
Checked an access point I didn't see last time, had a hole that was potentially big enough to squeeze through, albeit with a lot of contorting. Not wanting to risk getting stuck/trapped, I pinned it and moved on. This visit ended up being mostly a recce for the successful third visit.
Rechecked a couple of access points near the shaft, but found the holes to still be too small to get through. Made a mental note to recheck them on the next visit and moved on.
I nailed the house on this visit, although given it's sketchy condition, I didn't bother going inside, presumably there's nothing of interest in there, all the lovely documentation left behind is in the outbuildings, which made for a wonderful find, and made the second visit at least remotely worthwhile.
Data Protection
-
Loading Authorisation Slip -
Explosives Tracking Sheet -
Invoice -
Visit Number 3
Went with company this time, determined to nail everything. Didn't bother with the drain, although it was still open albeit covered, somebody had also tied a rope to it. Tried the hole I pinned, but couldn't contort myself around the debris to get down the tunnel and my friend took one look and said nope.
I'm curious as to what is down there though, as it's situated roughly above the RLC chamber. We could hear voices down there, turns out there was another group of explorers in the RLC chamber.
Does anybody know what could be down there? It's on a higher level, so the top of the hoppers would be my best guess.
Having failed to get in, my friend suggested climbing up the rubble heap to the top of the RLC access. Lo and behold, hiding just out of sight from the outside is a small hole! If only I had looked harder on my earlier two visits...
Conveyor -
Hoppers -
Control Panel -
Flooding -
Emergency Stop -
Motor -
Having covered that section we made our way over towards the shafts, and it appears somebody had been digging at the rubble, because there was a small enough hole to squeeze inside another conveyor chamber, albeit a much smaller one.
Switchgear -
Conveyor -
Hopper -
If you've read this far, congratulations, you've just read a massive report on a couple of conveyors...
Thanks for looking
