Story 29. Explosives.

Light work.

When I first began working in the mine I often stayed back to help with the loading of the shot with the blast crew.
The Mt Gunson Mine office up till the late1970s sat near the rim of the eastern part of the pit. Over time the mining operation had moved the pit a little closer.

A regular blast in the North Eastern corner of the pit one day caught every one a little by surprise when after checking the results and declaring the pit safe we arrived back in the office to discover one rock, about the size of a bowler hat had crashed through the roof of the office leaving quite an impressive hole in the roof and lay on the floor after having also passed with little effort, through the drawing office light table, destroying it on the way through.

The entire office complex, crib-room and toilets were soon after relocated much farther back and well out of harms way.



Protective Rubber:

CAT 769B

Up until the 1980's blasting of the ore body was done using electric detonators and a Beethoven exploder, this initiation device was housed in a box about the size of a loaf of bread, after connecting the detonator wires to it a crank handle on the side was given a few vigorous turns then a button on top was pushed sending an electrical current along the wires to excite and cause the demise of the detonators.

Until the construction of Brownies Bunker ( after Warren Brown the mine manager ) a heavy steel plate box lined on the outside with railway sleepers, and supported on heavy steel skids which made the task a little easier. Previously all electric initiations were done simply by parking one of the 40ton dump trucks with the rear of the truck toward the shot, close but not too close, with the heavy steel tray raised.
The shot firer simply positioned himself in front of the rear dual wheels and fired the shot while pressing him self up close to the tires. 
The successful shot was quickly followed by an impressive number of sizable rocks whizzing past, rebounding and pinging off the large tires.
             


Saturday Morning.

Jimmy Drain, one of the driller / shot firers on site, careful and confident.
Exactly what was needed when regularly letting off 10 or more ton of explosive on a daily basis.

I often found myself helping Jim, either loading shot or assisting him with loading or unloading the truck for a shot.
It was a Saturday morning, also a down weekend so the site was reduced to just a hand full of people mainly fitters or maintenance personnel, the two of us had loaded a shot in a new second pit after the company became interested in exposing an area of shallow ore quite near the surface in the original mine workings, in an area called, The Main Open Cut, cica 1920 / 50's, this work area was about three km east of the Mt Gunson, Cattle Grid Mine.

We had completed loading the shot an hour earlier than expected and had cleaned up the site in preparation for an early departure. We sat in the vehicle waiting for the advertised blast time to arrive so we could fire the shot, despite there being only a few people about and we were not expecting any visitors we stuck to procedure and the advertised blast time.

With a quarter hour before the blast Jim set off in his ute to do a safety and clearance inspection of the pit and general area making sure all was clear and no "unexpected visitors" had strayed into the area.

I remained in my vehicle parked across the only access road effectively blocking it to all traffic when Jim called me on the radio simply to check no one had passed by, then advised he was about to light the safety fuse before joining me parked seven hundred meters down the road and well away from the 5 ton of explosive we were about to detonate. 
Less then a minute later Jim's ute appeared as he joined me at the road block.

As my vehicle was facing the blast he simply pulled up alongside and climbed out of his vehicle to join me in mine as we waited.
I cut the fuse about a minute longer than normal he said as the two of us waited.

He checked his watch, 30 seconds he said.
Then, a short time later the ground shook and rumbled as the delays fired, although we couldn't see directly into the small pit we could easily see the rock and dust rising as the noise of the blast arrived.

We waited in silence for the dust to clear.

A good twenty seconds past when we both became aware of a strange whooshing noise.
We both sat in silence listening, as the noise grew louder.
"Incoming" Jim warned as we both realized a rock of unknown size, weight and velocity was fast approaching from some where high above.
We could only sit and listen as the noise grew louder hoping we weren't included as part of it's landing area.

A rock, about the size of a bread basket weighing in at ten or more kilograms landed with a definitive thump just meter behind Jim's Ute and less than three meters from where the two of us sat.
  
Hmm, he said, then after a pause, it missed.







The Last Overburden Blast in the Cattle Grid.   1986.

After a third nine month extension to the Cattle Grid Pit EMECO decided it was time to end the mining operation, this was forced in them not by the exhaustion of the ore body, but simply by the boom in the Australian Mining industry in general. EMECO were associated with a new mining company in Western Australia,  AWP (Mr. Alexander, Walker & Piper, who later went on to become Walker & Piper,) This new group had originally been the interested buyers of the CSR Mt Gunson Mining equipment, almost three years earlier.
They had a contract to open up a new gold mine near Laverton in Western Australia. At the time Australia was in the beginning of the mining boom, all forms of mining equipment were becoming hard to get, any new machines had a minimum of a two year waiting list.
The owners of this new Western Australian mine called ((Austwhim Resources NL, then, Austwhim, then Dominion mining) Cork Tree Well mine were becoming anxious for the operation to start.

The last Mt Gunson Mine overburden shot was a slightly bigger one than usual, in an attempt to help run down the stock of explosives we had on site.

News of the last shot spread far and wide, soon visitors from nearby stations rang asking if it was possible to watch, high ranking military and people from Woomera began to join the requests to attend.

We prepared and graded a suitable viewing area, decorated with pegs and coloured tape along with helpful staff to help look after the hundred or so visitors.

The pit and access roads were all graded and tidied.

The shot had been drilled and almost forty tons of explosives loaded and made ready, toward the end of the day the crowd began to grow in numbers.
Finally as the advertised time approached we performed the usual safety checks of the pit, both in and the surrounding roads and country side for any visitors.

The main road was blocked at the cattle grid and all was made ready.

I stood in the crowded observation area as the safety vehicle drove past tooting to indicate all was ready before he took up position by blocking off the assess road into the pit.

The shot firer was the only person in the pit and could be seen standing next to Brownies Bunker waiting for the signal to fire.

The crowd stood quiet and watching  to see what happens next.

I checked the time then at the exact time advertised I took off and waved my hard hat over my head slowly side to side. This signal was repeated by the shot firer almost a half a km away in the bottom of the pit who then disappeared into the brown square box.

Two or three seconds later I watched as the down line flash across the top of the shot at somewhere near 2280ft pr/sec initiating all the detonators.  Milli seconds later the first of the front holes went off the rest quickly followed in 15mill second delays later.
The ground shook in response as each 21mtr long 150mm diameter column of explosive detonated pushing a wall of rock dirt and dust into the air quickly obscuring the shot from further view.

From the growing wall of dust a large 15 or so ton rock appeared, it floated upward instantly causing me to question how something the size of a volkswagon could have survived the violence going on and yet remained intact and how it could have been kicked out of the shot.

The rock continued to rise as though powered by some invisible jet engine as it drew closer and larger rotating backward indicating it had somehow been booted from below and low down.
Still some way off the rock continued to rise easily passing the level of the gathered group of visitors, with insufficient forward velocity I noted it would fall well short of our location as it continued upward unexpectedly splitting in two almost equal halves both continuing to rotate in perfect formation as they began their descent, eventually landing with a dull double thud in the bottom of the waste dump some way below.

Curios I thought still puzzled by its appearance, while my mind ran through the maths of how much explosive would be needed to propel something with a 1500kg mass almost 100 meters into the air.

Turning I discovered I was the sole person still standing at the edge of the viewing area, every else one for some reason having moved well back.

Story 28. From Cowboy's to Prima Donna's.

The Early 1980's

After living in Tin Pan Alley (Single men's quarters) for a little over two and a half years I brought a 31 foot Caravan and with my wife moved into the small Caravan Park on site. As well as the caravan a 25ft transportable building was also supplied with each caravan site to provide additional accommodation space, the caravan park was located about 5km south of the Mill, near what was called the Town Center.
Two years later I was allocated a staff house along with a 14 hour work day,

The Town Center was a large community building where pictures were shown a few times a week, it housed a very basic store, for grocery items. a good size swimming pool, and a grassed sports oval that kept the kangaroos in the area well fed, their droppings becoming one of the dangers to avoid when being tackled to the ground during a football match.

Next to the swimming pool was single teacher, multi class primary school, children entering secondary school were transported by bus 30 km into Woomera each day.

As you approached the Town Center and the school, located on the side of the road was the usual road side signage warning of children crossing the road or playing in the area.
The sign also had a speed restriction.
Below the sign someone had placed a second sign that read,
"ANY CHILD KILLED ON THIS ROAD WILL NEED TO BE INSTANTLY REPLACED BY THE PERSON RESPONSIBLE".
This sign could be read two separate ways, though most saw it as humorous, some never got the ironic message.

The Mount Gunson Football team played and trained on the Oval and were reasonably successful in the district. After winning a premiership one year a few of the members of the team went to the famous SPUD'S Road House in Pimba after it closed one night, Spud kept a pet camel near by, as a tourist attraction, the team members crept into the pen and painted the unsuspecting dromedary in the team football colours.
 
A road sign at the top of the hill as you headed back toward the mill from the Town Center indicted the road, "slippery when wet" this also carried the message, "BEWARE  OF GRUESOME"  referring to a nick name and the driving habits of one of the many characters on site who had a habit of falling off the road.

In mining operators egos often become inflated as they gain new skills or become proficient at operating a particular machine or performing a task. It's all part of being a macho man, and the natural competitiveness of people having, in their mind demonstrated their superior skills.
Any operator displaying or acting superior in mining is usually taken as a good indication that trouble is not far away as these operators will often push the boundaries of safety, in search of new conquests, or in an effort to display their superior skill.

In actual fact the best and usually the most productive equipment operators are always the "quiet achievers" those who have nothing to prove and simply get on with the task in hand.

When I first became involved in mining the top operators wore fancy scrollwork leather cowboy boots, RM. Williams peg tight jeans and a western style shirt along with a tired well worn dusty cowboy hat.
Cowboys, seldom shaved unless going to town, they could, out smoke, out drink and out talk anyone in the bar.
Some Cowboys because of their chain smoking and total lack of personal hygiene often out stank the local goat population as well, as they spent very little time or effort maintaining themselves, or keeping their working environment clean, preferring to spend the working day operating an expensive machine while waiting to knock off so they could top up their hangover.

As earth moving machinery became more and more expensive the management and company directors began to look in detail at the operating costs and began to require operators to be more intelligent and to show they care not only for the machine but for the health and welfare of the company as well.

Starting in the1990's and becoming compulsory by the 2000's mines began requiring operators to pass both a drug and alcohol test each day prior to commencing work, effectively ending the reign of the rooting tooting Cowboys.

Not that they had vanished completely, Cowboys were quickly replaced by a new superior operator the, Prima Donna, a new breed of ego powered Macho men, who liked to also push the boundaries. Working out in the gym and drinking powdered encrustation supplements in the misguided quest to burn off every ounce of fat in an endless and financially expensive pursuit of the elusive body beautiful.

Like kids, occasionally we would come across a worker who always had trouble getting up early most mornings, they would lay in bed till the last possible minute when someone would bang on their door when they finally rose they would rush about to get dressed, and ready for work, often holding up the rest of the crew who were much better organised and a little pissed off having to wait for him every morning.
One of the crew dropped in to see me and ask how he could change the workers attitude.

Early the next morning the crew watched as I knocked on the workers door who after acknowledging the wake up call simply did as usual rolled over and went back to sleep.
I returned a few minutes later with the garden hose and put it in his hand as he lay in bed then went out and turned the tap on.
From then on his early morning calls were always accompanied with a short length of garden hose being placed in his hand in bed, leaving him with the unknown question of whether the hose was the real or fake one.

  
One of the mine shift crew had three operators who worked and played together, they arrived on shiny trail bikes taking a shorter cross country environmental destroying route and gloatingly beating the others who used the conventional roads. After work their shortcut enabled them to be home and enjoying a beer five or ten minutes before the rest of the crew arrived. This ability somehow this gave them an air of smug superiority.
A little while later I notice I was regularly arriving home long before the three riders wing dinged their way noisily down the road and into camp via their well traveled cross country shortcut even though I left work a half an hour after their departure

The short cut bike trail and crop location.

Curious, one day I decided to walk their bike trail where I easily discovering their marijuana crop, hidden close by among a grove of Northern Cypress (Mowantjie Willauwar) and thus answering the question of their delay.

Management decided to simply keep an eye on them along with one or two others we knew also into quiet horticulture, the idea being it kept them occupied and out of trouble.
The employment dept simply listing their job prospects as never to be re-employed or promoted.

As the crops aged and developed, a tiny amount of Glyphosate was often quietly added to the plants water supply.

Story 27. Highway Slaughter.

Mt Gunson Cattle Grid Mine, sat across the boundary of two station properties.

To the east Pernatty Station.
To the west Oakden Hills Station.

Between Oakden Hills and Mt Gunson mine was the Stuart Highway, the National Highway that ran northward from Pt Augusta, Alice Springs and finally on to Darwin completely crossing the continent from north to south.

Almost opposite the Mt Gunson turn off is an area known as the Bellamy Hills, a sandy area with patches of dense scrub, low trees and a sizable dam water supply, an ideal place for cattle to roam.

Most of the properties along the Stuart Highway ran sheep and cattle and in the early 1980's before the highway was sealed and with only sparse traffic using the road very few sheep and cattle station properties bothered with boundary or highway fencing.

Very late one cold night with the temperature nearing zero, news came through a number of cattle had wandered onto the highway and been knocked over by a passing semi-trailer, the story told was there could be as many a five dead cows spread over the road.

The overseer, his wife and a roustabout headed off in the inky blackness to investigate, taking with them their butchering knives just in case there was a possibility of being able to restock the stations meat supply.

They arrived to find a number of dead cattle spread along a section of highway. these they cleared from the road and after surveying the carnage the group set about butchering the cattle using the vehicle head lights to see by as they skinned and cut the beasts into manageable size pieces, placing them on a growing pile on the back of the station's utility.

It was pitch black and freezing and well into the early morning hours as the small crew were finishing off, in the distance they could see the lights of the first vehicle to use the road in hours, approaching.

They could hear it slowing down as it neared, obviously alerted buy the headlights of their vehicle parked off to the side of the road, eventually pulling up and stopping next to the stations vehicle.
The station overseer walked out of the darkness and into the head lights as the drivers window wound down.
The driver his eyes springing wide open as he watched a tall stranger completely covered head to toe in fresh blood and carrying a very large bloodied knife in his hand, approach.
The engine suddenly revved loudly as the gears crunched and the wheels began to screech along the bitumen as the terrified driver took of in an almighty hurry.

Leaving the small group a little puzzled by his response as they listened to the car as it continued accelerating away from them for quite some time.



     


      

Story 26. A close call in Clay.

West pit extension, EMECO. 1984

With the new owners of Mt Gunson came some additional equipment.

First were three well used CAT 770. 50ton Dump trucks, these were slightly larger than the CAT 769's we had.
One of the new trucks had an aluminum body with raised sides (hungry boards) making it unable to be loaded by the CAT 988b loaders even with their high lift extensions. 
Second was a CAT 992 Loader. to load the larger trucks, even this loader had difficulty reaching over the side of the aluminum body.

After making several requests to the work shop to have the additional extensions removed nothing happened.
After listening to the loader operator complain about them over several weeks and no action being taken, one night I removed the truck driver and climbed into the large loader and using the bucket knocked the bloody useless extensions off one side much to the delight of all concerned. Management didn't seem to notice.
During the first month of the new mine ownership the truck numbers increased from CSR' s 10 to 14 trucks, production quickly lifted, the price of copper doubled.
The new owners had given us just 9 months to extract the $14m worth of exposed copper a figure easily passed, management quickly decided on a second 9 month extension.

Frank, was the main 992 loader operator, although he was confident operating the large machine he lacked actual mining experience. We were opening up a new area to the North Western end of the pit, in preparation to strip the overburden during the second 9 month extension.

The big loader and the larger trucks were tasked with the removal of a 5 meter thick layer of clay cover.

I dropped in to inspect the progress and noticed Frank was cutting the clay face, leaving an impressive vertical face, plus parking the dump trucks parallel to the face while loading.

Standing on top of the exposed clay only a meter or so above the loader I waited for him to finish loading then indicated I wanted to have a word with him.
He stepped out and I informed him this type of clay would not stand up as a vertical face and I didn't want the trucks or the operators to be parked anywhere near the cut face, as it was prone to collapse without warning.

Frank heeding my advice agreed to change his operating method.

As he climbed back into the loader I walked away and had gone less than four steps when behind me there was a Whoomp. as a twenty meter length of the clay face fell away.

Returning to the edge I discovered Frank sitting in the loader all the windows smashed and buried up to his waist in the loose clay.

He looked up at me and said, yeah, I know, you told me so.

  
      

Story 25. Colour Blindness

Night shift.
South Australia: Mt. Gunson Mine.

During the winter months the temperatures at night often dropped well below zero, minus 8 the coldest recorded during my time on site by the thermometer that hung on the wall just outside the mine office for many years as the warm sandy soils quickly gave up their heat during the night.

While progressing through the management levels John Holcroft was the shift supervisor and for a while I performed the lesser role as his assistant.

John was colour blind in the extreme which also included to some degree night blindness, often when describing something to do with colour I would often be looking for a green something when all I could see was yellow.
John was also an amateur herpetologist, an ideal pursuit in a land full of reptiles many of which had the capability of killing a grown man in twenty minutes. 

While driving along the haul road John would often shout for me to stop. Then race from the vehicle to a blue salt bush off in the immediate area plunge his hand into a bush and pull out a highly venomous snake which to me had the same identical colouring to the surroundings.

The latest capture was quickly placed inside a small calico bag and tied securely for later study.
After recording details in a huge book he carried about, its weight, length, number of scales, type, and colouring which I would often be brought in to correct his interpretation it would then be released back into the wild close to where it was found.

Puzzled as to how he could see something so well camouflaged from quite impressive distances he would inform me the snake was quite a reddish to lite brown in colour hiding in a blue bush.

Often when seated opposite his desk it would take a little time to realise we were also accompanied by a snake or two coiled up on the desk as well, John was also in the habit of picking up dead snakes during his travels to add to his book of records.

I was often the victim who sat though one of his lectures on the variations in the local Western Brown snake something that was quite venomous, though it took just a little longer to kill you than the Inland Taipan which also frequented the area and one of the most deadly in the world.

John often pointed out the Western Brown also came in black, brown with black stripes and what was often called the five ring snake which could also have more than five rings, he also found a specimen that was closer to a creamy white colour.


John was often asked by the Adelaide University Herpetology dept to supply unusual or interesting samples.
During one of our sudden stops he discovered an unusual snake, one he had never seen before and sent many photographs to Adelaide Uni who also became excited by the find.
John sent the snake to Adelaide to have it identified and catalogued.
Later when inquiring about it's return he was informed the snake had been dissected, he stopped sending live specimens.

During dark rainy nights while making our rounds I was often asked to stop, and get out in the rain to collect frogs we had caught in the headlights of the vehicle, These were needed to feed Boris, his ill tempered 3 or 4 meter children's python.

A wild life television program contacted him one day in the 1980's to supply a snake for a show they wanted to film in and around Woomera. John had an excellent example of the required snake on hand so he agreed to take part.

 On the day of filming the snake, a Western Brown was placed in a foam box with ice to cool it down a little to make it docile for the well known wild life presenter to easily handle.

Showing up on the film site with the snake, John discovered the producers had chain-sawed a hole in the back of a large Myall tree opposite a large knot hole, the idea was for John to lay in a shallow pit behind the tree, suitably covered and camouflaged so when the presenter poked his hand in through the hole, John was to place the lethargic lethal snake in his hand so it would appear he had drag it out of the knot hole, he would then go on to inform the viewers of the details of this species of snake.

John, seeing what they had done to a very slow growing 250 year old tree, which, to a casual observer, looked like a rather unspectacular looking tree, they had effectively killed it, he was furious and refused to take part in the filming, informing them the tree had been growing in that location long before Captain Cook had discovered Australia.


Tourists.

Often a tourist vehicle would pull up in front of the mine office. Most times these were sent by the Woomera Police after the occupants had reported a snake had climbed into the vehicle while camping several days before. The occupants would climb out of the car wearing every garment they had with them as padded protection should the snake attempt to bite them. Often this was how people arrived on site in 40c (103f) degree temperatures.

John would boldly open the car and begin unloading their possessions one piece at a time, opening, unfolding, lifting, shaking in search of the wayward reptile, if nothing found he would then venture into and under side of the vehicles fittings, flaps and substructure until it was either found or he was satisfied none existed.
Any discoveries were bagged tied, measured, recorded, and identified before being released back to the wild.



     

Story 24. War of the Dozers.

CAT D9L

 

Komtsu Dozer.

Shortly after EMECO took over Mt Gunson Mine from CSR in 1984 a well used Komatsu D4 size Dozer appeared on site.

Compared to the two much larger D9 Dozers we used on site in the mine, the tired little Komatsu was less than one quarter of their size and was simply too small to be of any use to the mining operation, we attempted to use it to push off the tip heads, but with dump trucks arriving every minute to deposit another 50 ton of overburden the tiny machine quickly became completely overwhelmed by the task plus it was in constant danger of being run over by even the smallest of equipment on site. The other problem was the tracks would often fall off usually in a most inappropriate location, or when reversing the blade side arms would sometimes become unattached and the blade would be dragged along by the hydraulic lift cylinders.

Originally the Dozer was proposed for use in the mill, management hoping its size would make it handy to assist with clean ups and getting in and among the various crushers, conveyors, or pushing in the feed at the main surge pile when the feed cone became to low. After trials in the mill it was found the task of pushing in feed could be performed much quicker and easier by one of the many 988B front end loaders we previously used.

The little dozer sat unused, in a quiet corner of the mill.

A problem arose when it was discovered who ever had this Dozer in their possession, was though the complexities of the P&L (Profit & Loss) accounting paper work being charged for its hire and use whether in use or not, (I suspect this Dozer was owned by one of the company directors and simply put out on site to appear as a hire and used to supplement his/her income ).

The Mill decided in an effort to eliminate the unwarranted cost, to secretly walk the machine 3km and hide somewhere it in an unfrequented part of the mine area.

The mine upon discovery of the diminutive tracks would easily locate its hiding spot and having no use for the Toy Dozer loaded it into the back of one of the dump trucks and driven back to the Mill where it was simply tipped onto the surge pile.
And so started a sort of to and fro war between the Mill and the Mine, where the unwanted Dozer made numerous trips up and down the haul road as each department fought to retain non possession .

Occasionally if the dump truck operator was engaged in carting ore to the mill and given the task of returning the Dozer, it was often accidentally tipped off into the actual primary crusher, when the driver simply forgot about the change of load. By the time the sound of screeching metal on metal as the tracks slid along the tray while exiting the truck was heard, it was far too late for the truck driver to stop the inevitable.

After returning the Dozer and depositing it onto the bottom of the surge pile late one evening, the Dozer war came to a quiet end, at least for three or four weeks.

While trying to reconcile his books at the end of the month the accountant noticed neither the Mine or Mill had included the tiny Dozer in their monthly figures, each department claimed not to have used or be in possession of the machine  and both claiming not to have seen or used it for over a month.

I was sent out to search the entire mine site and find the missing machine, management fearing it may have been stolen from site

After an entire day of following very old tracks and looking in places it was last reported the trail seem to have gone cold.

Searching through the service records I discovered the last sighting report was from the serviceman who had refueled it as part of his normal daily service of all equipment on site, and had listed it as being located in the Mill.

After spending a few hours on a 988 loader moving part of the huge surge pile I uncovered the dozer having spent the month completely buried under several thousand tons of crushed rock.

The Dozer then spent the next several weeks tagged out of service and parked out of the way near the workshop, conveniently forgotten, while waiting to be inspected for damage before being returned to service.

Story 23. Bangalore Torpedo's & Surge Bins

Warren Brown was the mine manager during CSR's ownership of Mt Gunson Mine, he encouraged employees to learn new kills and take on the occasional challenge.
This approach encouraged knowledge, experience and occasionally something a little unexpected,

After one of the overburden shots had been cleared and all the material had been dug out and after the area had been cleaned up it was noticed a large 500+ton rock hangup had occurred on the back wall of the overburden shot. This was a section of rock that had been included in the shot but for some reason the explosive had failed to move it so it hung as a large bulge of rock 15mtr long and four meters high and about a meter and a half thick, attached to the face, there were several original drill holes still visible passing completely through the back of the hang up, all empty and spaced 2.5 mtrs apart.
One of our training shot firers was given the task of calculating the required amount of explosive to enable this problem to be cut from the wall without damaging the wall face behind it.
The rock type known as Whyalla sandstone consisted of a mix of layers with numerous fault lines and variations in the actual hardness of the rock itself, this was a very difficult material to blast correctly and if not enough care was taken when loading the explosives, it would reward the shot firer by producing large 5, 10, or 15+ ton boulders with ease, making it difficult for the Front End Loaders to shift move or pick up and place into the back of the Dump trucks.

After careful calculations the suggested amount of explosive was loaded into a series of Bangalor torpedoes. A Bangalor torpedo is an explosive charge placed within one or several connected tubes, Originally used by combat engineers to clear obstacles that would otherwise require them to approach directly, possibly under fire. It is sometimes colloquially referred to as a "Bangalore mine", "banger" or simply "Bangalore" (wikipedia)

In this instance the explosive was placed in several lengths of 75mm PVC pipe. This allowed the explosive to be slid down into the existing holes which were open top and bottom.

The explosive in the form of a packaged sausage was tied with down line and after measuring the position with the aid of a tape measure lowered over the side of the face which then produced the measurement to lower the sausages down inside the PVC pipe to the required depth.
After tying the down lines together and clearing the pit, the time came to fire the charge, with the ultimate aim to sheer off in a clean cut and leave the face clear of the dangerous 500ton rocky hangup.

Warren Brown and a small group stood well clear on top of the pit watching as the charge was detonated.
A flash of det cord a milli second or two later the Bangalor Torpedo's all detonated sending rock and dust up and down the face behind the hangup, the sharp crack of the explosive reaching us a few seconds later.
As the dust cleared it became apparent the hangup had not shifted at all.
We waited, a minute and it became apparent nothing was going to happen.

Warren turned to the disappointed shot firer and began to explain that often even after doing all the calculations and planning it is always better to slightly overcharge the holes with explosive.
He then began a lecture on calculations for mass and quantities of explosive, when the overhang suddenly and quietly slid down the wall as one complete piece before noisily shattered into small pieces as it hit the floor ten meters below leaving behind a perfectly clean face looking as though it had been cut from the face with a knife while leaving half the drill hole still visible in the remaining face, making it a perfect result.

Warren shut up for a moment watching as the scene unfolded before him, Then, he went on,  there is beginners luck to consider, he said finally.

Mt Gunson Mill stock pile and round Surge bin(silo)

The Surge bin

At start of the feed conveyor in the Ball Mill stood a surge bin, this was a tall silo like structure that stood twenty meters tall and about six in diameter, the top was capped with a conical shape roof of corrugated iron to help keep the crushed ore dry.
It's purpose was to collect the final crushed rock, the fines and feed it onto the feed conveyor at a rate to maintain the constant flow of feed into the Ball mill where it would be ground down to a fine slurry to enable the copper and other minerals to be separated from the waste rock.


Occasionally the contents would hang up inside the bin, a series of compressed air jets fitted at various levels and locations about the circumference of the bin could be activated to blast the material loose.
Sometimes the air was unable to shift this material, when this happened the internal volume of the surge bin was reduced making it difficult to maintain a constant feed flow.
The solution was to lower a shot firer in through the top of the bin on a bosuns chair with an auger where he would drill a series of holes all around and at different levels through out the hang up material and cut a 20 or 30 mm slice from one or two plugs of the sausage explosive and insert it into the augured holes taking care not to over prime the entire bin with explosives. The object was to shake and loosen the hang up.
After one Christmas I was returning to the mine after having a week off to discover the entire roof of of the surge bin completely missing.

One of our ex army shot firers who had been staying on site over the Christmas break had been asked if he could give the bin a bit of a shake up. Miss-understanding the instruction of using only 20 to 30mm slices of the 70mm sausage explosive he took it to mean 20 to 30% of the explosive in each hole. The result of the using five plugs of explosive in an overcharge quickly removed the entire roof in a spectacular fashion sending it flying hundreds of meters into the air where it rained sheets of twisted corrugated iron down all over the mill area.

Oh well,