Explosives: Tools for Progress
- 1970s
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Transcript
00:00:01 Just strain your wires, don't let it drill.
00:00:06 Now, go back two feet that way.
00:00:08 We're all ready, let's clear them out.
00:00:10 Okay.
00:00:14 Let her go.
00:00:17 Startled? I thought so.
00:00:19 Perfectly natural human reflex. Somebody's blasting.
00:00:23 It's a sound you hear all over the country today, the sound of progress.
00:00:27 Want to see what we mean?
00:00:30 Well, first, an explosive is a very powerful tool.
00:00:38 Without this tool, you wouldn't have, oh, electric power, dish racks, moon rockets, or potato heaters.
00:00:43 Sure, back in history, men raised pyramids, dug coal and iron, but think of the cost.
00:00:48 And without explosives, we'd still be there.
00:00:50 Start with this excavation.
00:00:52 Manhattan Island is founded on solid rock.
00:00:55 Historically, explosives have been an essential tool in the city's growth.
00:00:59 Turn of the century, they helped tunnel the world's first great subway system.
00:01:04 The descendants of these workers live in buildings taller than their grandfathers would have believed possible.
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00:01:18 That trap rock island supports the skyscrapers,
00:01:22 but their basements have to be blasted out of it.
00:01:25 The last shot here took place an hour ago,
00:01:28 and the crumbled rock is being mucked out and hauled away.
00:01:32 The next one goes before the end of the day,
00:01:35 and before then, other blasts will be set off in lots of places for lots of different reasons.
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00:01:49 In three years, a 47-story building will stand in this growing crater,
00:01:54 and plenty of others are rising around it.
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00:02:04 Explosives, where next?
00:02:07 ♪
00:02:13 Some 3,000 miles across the country,
00:02:16 the Columbia River runs between the scrub wastelands and granite hills of eastern Washington.
00:02:23 To harness its flow for irrigation, flood control, and the generation of electricity,
00:02:29 construction was begun in 1933 on one of the mightiest structures ever built by the hand of man.
00:02:38 Completed in 1941, it stretches 4,300 feet across the gorge
00:02:45 and towers 550 feet above the boiling waters below.
00:02:49 ♪
00:03:00 Grand Coulee Dam.
00:03:04 Hundreds of tons of explosives were expended on that site.
00:03:08 Now, years later, work begins again on a project to widen the gorge
00:03:12 and extend the dam for a third power station.
00:03:15 This time, 36 million tons of granite will be excavated in the first two stages alone.
00:03:21 Explosives are still the only remotely conceivable tool for this job.
00:03:27 Shots of the magnitude set off here usually take place twice a day at shift change,
00:03:32 when the area is clear of men and machines.
00:03:35 The next one is set for six o'clock,
00:03:37 and those huge electric shovels are digging out rubble from the last shot in 25-ton bites.
00:03:44 It might not look necessary,
00:03:46 but the blasting operation here will be just as precisely controlled
00:03:50 as it is in the middle of Manhattan.
00:03:52 ♪
00:04:00 The dam and its generating station are still operating,
00:04:03 producing power at full capacity,
00:04:05 and a wayward chunk of rock in that electrical equipment below
00:04:09 or a shock to the dam itself could have very serious consequences.
00:04:13 ♪
00:04:18 If you want to get to the Pacific Ocean from the Atlantic by sailing east,
00:04:22 there's a way to do it.
00:04:23 The solution to this geographic riddle occupied the considerable energies of our 25th president,
00:04:29 and in seven years, required 61 million pounds of explosives
00:04:33 to blast a big ditch across the isthmus of Panama.
00:04:37 280 million cubic yards, and we're back again for more.
00:04:42 Today, the size of the vessels and the volume of traffic
00:04:45 have made it necessary to widen the cut.
00:04:48 But here, the blasting materials must function underwater
00:04:52 as well as in the dry earth and rock.
00:04:55 No big uncontrolled bang here either.
00:04:58 The vital commerce of ships must continue to pass while the work goes on.
00:05:02 Two shots were set for today,
00:05:04 and the underwater debris from the first is already being brought up.
00:05:08 The second follows within a few hours.
00:05:11 ♪
00:05:14 Three separate projects, Panama, Grand Coulee, and New York.
00:05:19 Each one an example of the hundreds of tasks performed by industrial explosives,
00:05:24 and each one presenting a different problem to the engineers who will use them today.
00:05:29 The first step in any blasting project is drilling.
00:05:32 Hole location, depth, and the overall drilling pattern for each shot
00:05:37 are but a few of the expert calculations made in the course of the job
00:05:41 by geologists, civil engineers, surveyors, and explosives engineers.
00:05:47 What's the most productive way to keep the shovels working?
00:05:51 A delicate relationship exists between the explosives used
00:05:55 and the capacity of the earth-moving equipment.
00:05:58 The rock must be broken into fragments neither too small nor too large.
00:06:04 It must be easy to get at and available for loading at the right time.
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00:06:17 At Grand Coulee alone, $12 million worth of heavy equipment
00:06:21 must be kept operating at peak efficiency.
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00:06:41 The flat surface of this white new cliff face
00:06:45 is the result of a precision blasting technique called pre-splitting.
00:06:50 When these drill holes are finished and the charge is detonated,
00:06:54 another section will be sheared away cleanly and smoothly.
00:06:59 Out on the level surface of the cut, another formation of drilling rigs clatters away,
00:07:04 each with its own attendant, like giant mosquitoes fastened to the rock.
00:07:12 Forty feet down for each borehole.
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00:07:24 This final series of holes in the pattern must be ready for today's shot.
00:07:29 No time for a broken shaft or a dull bit.
00:07:36 ♪
00:07:39 Next, the most important ingredient of all,
00:07:42 the explosives themselves must be readily available to the blasting crew.
00:07:46 ♪
00:07:49 This storage magazine in New Jersey is within an hour's drive of the New York site.
00:07:55 It is isolated, fire and bullet resistant, and kept securely locked.
00:08:00 ♪
00:08:07 Blasting caps are stored separately from the explosive materials themselves,
00:08:11 and both are transported in compliance with the laws and regulations
00:08:15 of the Federal State of New Jersey and the Federal Department of Transportation.
00:08:20 ♪
00:08:27 Safety is the word in the vocabulary of explosives.
00:08:31 Even the truck itself is thoroughly checked before it starts its drive to the excavation site.
00:08:37 ♪
00:08:44 It makes common sense to treat a tool of this potential power with care and respect,
00:08:49 but common sense isn't enough.
00:08:51 The men involved in the storage, transportation, and use of commercial explosives
00:08:55 observe standards of safety and apply operating procedures
00:08:59 developed over a century of industry experience.
00:09:02 Most of these self-developed procedures have been written directly
00:09:05 into the safety regulations and laws for this vital industry.
00:09:09 ♪
00:09:16 The effects of each blast are closely examined.
00:09:19 Here at Grand Coulee, a decibel counter and a seismograph monitor the shots.
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00:09:31 Sound and shock waves are recorded to ensure that noise levels
00:09:35 and ground vibrations stay within established limits.
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00:09:42 At a major project like Grand Coulee or the canal,
00:09:46 the various explosive ingredients are often stored individually
00:09:50 and mixed together on the job site.
00:09:53 One of the blasting agents used at Coulee is a mixture of ammonium nitrate and a fuel oil.
00:09:59 This explosives engineer supervising the loading
00:10:03 might have used the same material in mining, quarrying, road construction, and flood control.
00:10:09 ♪
00:10:14 Here as in New Jersey, separate storage for blasting caps
00:10:18 and they're carried to the loading site in a smaller truck.
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00:10:25 Explosives have not only become more sophisticated over the years,
00:10:29 they've become safer.
00:10:31 These ammonium nitrate prills are only used as an explosive
00:10:35 after they've been mixed with other ingredients, loaded and primed.
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00:11:00 At the canal, another type of explosive is required.
00:11:04 The problems of underwater blasting are solved by using a water gel or slurry,
00:11:09 here pumped into plastic bags.
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00:11:21 Explosive makers don't sell bricks dumped on the job site and left to the builder.
00:11:27 Over the years, the explosives industry has developed the know-how on the special uses of its products
00:11:33 and up-to-date technical information about them is made widely available.
00:11:37 Even in the jungles of Panama, this truck is delivering a modern explosive product
00:11:42 into the hands of qualified technicians.
00:11:46 The same type of explosive is used at Grand Coulee for drill holes into which ground water has seeped
00:11:52 or in irregular holes drilled through pockets of softer rock.
00:11:56 The gel flows in and completely fills the hole.
00:12:00 ♪
00:12:07 The ingredients are suspended in water to produce a high-density, high-energy,
00:12:12 semi-fluid explosive that can be pumped into any size borehole.
00:12:17 Hand-loading holes with dynamite here could take days.
00:12:22 ♪
00:12:30 Ammonium nitrate fuel oil mix at Grand Coulee, water gel at Coulee and the canal,
00:12:36 and more conventional dynamite from storage in New Jersey,
00:12:40 all must be available at the proper time and in sufficient amounts for the loading crews
00:12:45 and the three shots at the end of the day.
00:12:49 So far you can begin to see three big reasons why explosives are so vital to our standard of life.
00:12:57 A fourth example might be the highway this truck travels on.
00:13:01 Passenger cars, semis, good humor wagons, motorcycles,
00:13:05 all pass smoothly and quickly over this road
00:13:08 and the thousands of miles of interstate highways constructed with the aid of explosives.
00:13:14 ♪
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00:13:27 What's this domestic scene got to do with it all?
00:13:30 Well, highways, dams, canals and skyscrapers are unmistakable symbols
00:13:35 of the part played by explosives in our lives.
00:13:38 Other contributions are a little less apparent.
00:13:41 It's a bit like the house that Jack built, or in this case the meal that Jill cooked.
00:13:47 ♪
00:13:50 This is the blast that mined the ore,
00:13:53 to forge the steel,
00:13:55 that shaped the knife,
00:13:57 to peel the, well the rhyme goes on and on,
00:14:00 but these kitchen utensils are made readily and cheaply available to all because of explosives.
00:14:06 ♪
00:14:08 These irrigation ditches, dug with explosive charges,
00:14:12 carry water to growing vegetables.
00:14:15 ♪
00:14:21 And explosives help pipe that water into the sink,
00:14:24 which is itself made of, you see what we mean?
00:14:28 Salt for seasoning was mined with explosives, marble for the coffee table.
00:14:33 ♪
00:14:36 And even further removed,
00:14:38 the plastics and synthetics you use derive chemically from things like
00:14:43 coal mined by, guess what?
00:14:47 ♪
00:14:50 And natural gas, the same gas that heats the oven,
00:14:54 that bakes the bread and the pie,
00:14:57 is carried in pipelines, put in trenches, dug with.
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00:15:05 This kind of game can be extended indefinitely,
00:15:08 even to such highly sophisticated uses
00:15:11 as the precise explosive charges used to separate rocket stages
00:15:15 in our reach for the stars.
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00:15:36 At Grand Coulee, the drilling is finished.
00:15:38 The blasting area cleared of equipment and the holes ready for loading.
00:15:43 Each hole is rechecked for water content, depth, and location.
00:15:48 ♪
00:15:56 In fact, the engineer keeps an extensive biography
00:15:59 of their individual peculiarities.
00:16:02 ♪
00:16:05 Precision and control, no fly rock in the transformer yard,
00:16:10 no cracks in the dam.
00:16:12 ♪
00:16:15 First, the primer charge is lowered to the bottom,
00:16:18 but each hole will not be set off at the same time
00:16:21 for a very important reason.
00:16:23 The numbers on these detonating cords
00:16:26 refer to the exact number of milliseconds of delay
00:16:29 between the detonation of each hole, starting from zero.
00:16:34 Primer set, and the holes are ready for loading.
00:16:38 ♪
00:16:42 In New York, it's already begun.
00:16:45 But here, the blasting material selected is dynamite.
00:16:48 And here, electrical initiation.
00:16:51 ♪
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00:17:04 Several sticks of dynamite,
00:17:06 and then the primer is placed further up the hole.
00:17:09 Sand is used to seal off the top.
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00:17:32 Loading at Grand Coulee.
00:17:34 The water gel goes first.
00:17:36 A job like this used to take more time and more hands.
00:17:41 Bulk-loaded explosives pumped right from the truck
00:17:44 means speed and simplified handling.
00:17:47 And that means economy and safety.
00:17:50 ♪
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00:18:07 The rest of the hole is filled up
00:18:09 with the prepared ammonium nitrate mix.
00:18:12 ♪
00:18:19 ♪
00:18:26 At Grand Coulee, the job situation calls for non-electric initiation.
00:18:31 And the arteries of detonating cord connecting each hole
00:18:34 explode at four miles a second.
00:18:37 ♪
00:18:39 Remember those cords with the numbers on them?
00:18:41 Well, the engineers intend to shape their rock pile.
00:18:45 The center goes up first,
00:18:47 and into that space the sides fall
00:18:50 by lifting the roof up and collapsing the walls.
00:18:53 You build a pyramid, easier to get at.
00:18:56 ♪
00:19:00 New York, Grand Coulee, and Panama.
00:19:04 Loading here is almost finished.
00:19:07 Water gel is pumped into the onshore holes.
00:19:10 ♪
00:19:16 And frogmen assist in loading and priming the wet hat.
00:19:20 ♪
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00:19:39 But in New York, there's one final step.
00:19:42 Blasts taking place in populated areas
00:19:45 are controlled not only by the kind and amount of explosives used,
00:19:49 but by laying on huge wire rope mats to contain all flying debris.
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00:20:13 At every site, the whistle clears the area,
00:20:16 and hours of careful preparation are over.
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00:21:13 Those three shots today set off thousands of pounds of explosives,
00:21:18 and they did their jobs quickly, safely, and economically.
00:21:23 Man has moved rock, mined coal and iron ore,
00:21:27 and dug ditches with pick and shovel or his bare hands.
00:21:31 In some parts of the world, he still does,
00:21:34 but with explosives, the right kind,
00:21:37 at the right time, and in the right place.
00:21:41 His constructive energies can be multiplied a thousandfold.
00:21:46 When the work here is finished,
00:21:48 Grand Coulee will be one of the largest
00:21:51 hydroelectrical generating systems in the world.
00:21:55 ♪
00:21:59 The next time you hear,
00:22:02 you'll probably still jump.
00:22:05 But when you think about it,
00:22:07 you'll recognize it is the sound of progress.
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