Overview of Well Drilling Techniques

I know it's really cool. It's 325 oh Hello, sorry. I was just telling a friend here blah blah blah This is so dumb Okay, so let me just start by explaining what's in the ground that we're going to be dealing with while drilling the well. So we have bedrock that's deep down. That's where we ultimately want to get to. But on top of that is a certain amount of what you call overburden. Overburden is clay and sand. and gravel and boulders and water that's sitting on top of the bedrock. Now, in some areas, you'll see bedrock outcropping right on the surface, and there is no overburden at all where you see that. In other areas, there'll be hundreds of feet of overburden. It really depends on geological processes that I really couldn't tell you much about. So you got to get through that overburden and down to bedrock, and that can be a variety of different types of rock. In my case, it happened to be shale. So in order to get down to that water, you've got to drill through the overburden and into the bedrock and hit water. And, you know, in my mind, this whole thing, before we even started, I found this to be completely amazing. Because deep down inside, under the ground like that, that is like unknown territory. It's like a frontier. It's like alien almost. It's like going down to the bottom of the ocean. I mean, we don't, you can't just go down to the ground. I mean, there's all kinds of organisms and all kinds of things that like, you know, are totally foreign. to us down there I imagine. So I got really excited about the whole thing and when talking to different well drillers they started telling me all different stories like one of the coolest ones is when sometimes when they're drilling they'll actually all of a sudden the drill just goes just drops and a reason for that is because you can hit a cave. They have hit caves that like are not accessible from the outside world. They're completely uncharted. There no one has ever been in them before and now we just broke a hole into them and you know it just Boggles the mind like you know what does that look like? So there are two main types while really there's one main type of drilling that's done around really surround here these days and that is A rotary drilling machine. This is a giant machine on a truck. It's diesel powered and it has a hydraulic a giant hydraulic pump on it and What it's doing is it's it's a basically like a giant hammer drill if you're familiar with like a DeWalt hammer drill You might buy at Home Depot. It's spinning But as you apply pressure to the drill bit pushing up, it starts hammering, like hammering down. The idea is it's fracturing the masonry that you're drilling into, or the rock that you're drilling into. And that is the exact same thing that's going on with the rotary drilling machine. So another method that's still used around here, although a lot less used, is the cable tool. And that is basically, instead of a rotary motion, it's literally just a big drill bit that is just lifting up and then slamming down and pa-pound, pa-pound, pounding. into the earth and fracturing up that rock. We definitely gave each a lot of consideration and I'm going to cover that in another video. But we ended up choosing the common method nowadays, it is the rotary drilling machine. So this machine arrives on a truck, it's got a support truck that's filled with a couple thousand gallons of water and this machine has a giant boom on it that lifts up in the air, it's got a drilling head up on that boom that travels up and down about 20 feet. And that is the head. that is spinning and that is hammering and then that's all hydraulic powered. To get started they get the machine all leveled out so it's got these feet that come down and level out the machine because if the machine is not level you're not gonna drill a straight hole down into the ground it's gonna be angled at whatever angle the machine is at. So once it gets leveled out they start the process by attaching the drill bit which is like this giant like tri wheeled grinding tool. So these little grinding heads I believe they spin bin and the drill head, the drill bit actually has holes in it that shoot out water and compressed air and I'm going to get to that in a little bit. So the machine starts drilling. It sends down a 20 foot length of pipe. Once it gets there, a little collar is secured around the end of that 20 foot shaft to hold it from falling into the hole and then the drilling head, the power head, rises up 20 feet. and then there is a spindle that swings over and drops off another 20 foot shaft and is attached to the power head. That comes down to the previous 20 foot shaft, and then it spins and threads it into the previous one. And then it goes down another 20 feet, locks in the pipe around the collar, and then the power head rises back up 20 feet, and again ...and until you hit bedrock. Once you hit bedrock, that's when the casing comes in. So the casing is a six-inch steel pipe that keeps all the overburden from falling in the hole. It's necessary because the overburden is, um, it's sand and dirt. and mud and all these and gravel and that can just fall collapse and fall fill up this hole so we need something to to keep all that stuff out so we grab a piece of a 20 foot length of steel pipe and basically it's a very similar process to the the drilling. The same mechanism grabs it, spins it, pushes it into the ground. So each 20 foot length of casing has threaded ends. So one side is male, the other side is female. So when they're connecting each of those lengths, they spin the top one onto the previous one that's already in the ground. And they thread it in, makes a tight connection. Then he comes back and arc welds it completely together. Because think about it. You might have to go down, you know, maybe you're lucky you only have to go down. down 40 to 80 feet into overburden. Or maybe you're not lucky and you have to go down, you know, 100, 200, maybe even 300 feet of overburden before you get to the bedrock. The spinning action that's pushing that casing down, there's a lot of friction against the sides of the hole, the drilled hole against the overburden. And you don't want to compromise those connections. So by welding it, by threading it and welding it, you're making a super strong shaft that just is not going to compromise. as you're pushing that casing down. The very first section of pipe that goes in, they attach a drive shoe to it. So I guess that's like a, I don't know if it's hardened, but it's definitely like a thick piece of steel that just threads onto the bottom of that pipe. And the point of it is, is that once you get down to bedrock with the casing all the way down, basically what they turn on the hammer drill portion of the power head, and it actually just literally drills, pounds and drills that... drive shoe and thus the whole casing into the bedrock about eight to ten feet. That drive shoe, if you did that with just casing, it would probably break up the steel. But the drive shoe is super strong so it's able to keep everything intact while that's happening. So now we're eight to ten feet into the bedrock. So we're locked in. All that overburden can't get into the casing now because we come out of the surface. So nothing's gonna fall on the top and we're in the bedrock on the bottom. So we're sealed. We're sealed as far as the overall design is concerned. the overburden goes. Next thing you got to do is actually seal around the outside of the casing into the bedrock. The hole that's being drilled for the casing is two inches bigger diameter than the casing itself. So that is what's creating. There's approximately like, you know, half an inch to an inch on each side gap that we need to fill up. Because what we don't want is surface water ultimately making its way down through or really contaminated surface water, which is possible because we are. we are humans and we make a mess of things. It working its way down around the outsides of the casing and thus into the bedrock, contaminating the water supply. So they would put in something called grout. That is, in my case, they used a bentonite clay, the powder like cement is, and they literally just dumped it in. And then, you know, water will mix with it and there is moisture down there and it will harden and totally seal up the outside of that casing. I've seen some other cases where like they're purposely putting in more material to come up with. up all the way to the surface. My well driller said that a lot of the debris that comes out of the top of the casing as we're drilling into bedrock will fall in and fill the rest of the gap between the casing and the overburden. In my case, it turned out I had about 180 feet of overburden before we hit bedrock. The first 15 feet was some big boulders and it was gravel and a little bit of clay, silty stuff, but then it just turned into like solid clay. The nice thing about that is that clay is not very permeable. It basically, since it's just like muck, it like oozed right in and suctioned itself to the sides of the casing. Which is good, because that's gonna help keep any kind of surface contamination from working its way down. to groundwater or even alongside the casing. So in addition to the grout that the fact that I had like a hundred and whatever was 65 feet of just mucky clay is gonna seriously help keep any surface water contamination from ever getting down there. So with a rotary drill you know you've hit water. When literally water just erupts out of the hole. It was pretty violent actually. You got all that compressed air blowing all the debris and all the water used for drilling and cooling the bit and all that up out of that hole and you see that coming up. It's you know, it's not too much. It's pretty consistent. Just a spray that's coming up. But when we hit water man, holy cow, it just blew right out of there. It's gushing and almost, you know, if you're standing in the right place, you would have gotten knocked over. That is when we knew it was time to stop and assess the situation and I ended up with about 10 gallons a minute of flow in the end. Alright, so after you've got your hole drilled, your casing in, and you're drilled all the way down to the bedrock and developed a good amount of water flowing into it, into your well, it's time to drop the pump in. So I think they took inch diameter PVC and threaded it into the top of a 220 volt impeller pump meant for wells. And right down on the bottom of that PVC, right above the pump, they They got this blue thing, looked like rubber, and I didn't ask, but I believe it was to push against the sides of the casing or the bedrock, wherever they dropped it, and it's to keep the pump centered in the pipe. Could be wrong on that, so if I'm wrong, please correct me. I imagine when the pump goes on, it's a pretty powerful pump, so it's probably going to want to move around a little bit, at least on startup. So that's just going to keep it in the middle instead of banging against the side of the hole. So, yep, up with that. They ran two 110-volt hots for the 220 and a neutral. And they basically, similar to how they were doing the casing and the drilling, stick by stick, 20 foot lengths, they dropped the pump down and then connected the sticks of PVC to each other just by threading them. They have a male and female thread. So it's standard, I guess, PVC water pipe. I don't know if this is drainage pipe or what. PVC is usually drainage pipe from my experience. This isn't under pressure. It's just a pump pumping up to a tank or another pump. I'm not sure the details on that. pipe. Yeah, so in this case, you can do this by hand, but they had a truck with a little crane on it with a little attachment that has a collar on it that allowed them to hold the pipes vertically and they're able to, that's how they're able to thread them on top of each other and then lower them down together. They went down 180 feet and that was not an arbitrary number. That tells you how far down the water is. Temperature is 72.4 feet. It's going down. Oh, I see. Okay. So it's got like some type of sonar or something? It is sonar. Yeah. Sonic sonar or whatever. Okay, cool. So, let's take a step back. So the whole depth of the well was 325 feet. We hit water at 300. They went down another 25 feet. not exactly sure why I imagine it's probably because any sediment coming in from the water veins it has a chance to to settle down low but below where we hit water so it never clogs up down there but again Again, if I'm wrong on that, please correct me. So then, when we drilled it, the pressure of those veins pushed water in and rose that water level in the well up to 52 feet below the surface. And that's where it leveled off. Then at that point you had enough weight of that water holding back that pressure. So when we take water out and bring the water level down lower than 52 feet, it'll work its way right back up at about 10 gallons a minute, because that's the rate of flow coming into the well. So we dropped the pump down to 180 feet. So that's approximately 126 feet below the level of the water in the well, in the casing there. So if you think about that, you got a little bit over one gallon of water per foot of a six inch pipe or six inch hole there. You got about 126 gallons, maybe about 130 gallons sitting on top of that pump. Now that's all the water that's ready to be pumped out. So yes, we have 10 gallons a minute, but we can pump out as fast as we want, as fast as that pump will let us. for that first 130 gallons. So very rarely are we ever going to be pumping out 130 gallons at a time. Generally, you're pumping into your home, filling up a pressure tank, and your pressure tank is never really more than 20, 30, 40 gallons. So it's going to kick on in a normal house situation. It'll kick on, fill up that tank, and then kick off again. So it can really just pump as fast as it wants. In my case, I'm probably not going to be using this well water as a primary source. It's probably going to be backup, probably filling up a cistern when we don't get enough. rain. I'll probably just limit the rate of the water flow and I can. I got a valve, I got a adjustable valve here so I can just keep running it until my cistern is full without running out of that 130 gallons. But keep in mind also is that as you're pumping that stuff out new water is coming in so... You probably actually have way more than 130 gallons before you actually run dry get the water level down that far. So the rate of water coming into my well is around 10 gallons per minute. The rate that my pump can pump water out of the well is also about 10 gallons a minute. So if you think about that, as I start depleting from that 120, 130 gallon reservoir sitting on top of the pump, the water from underground is refilling the well at about the same rate that the pump is pumping it out. So... I can never run out of water unless water stops coming up from the ground. I can pump out as fast as I want, and it'll just keep refilling as I'm pumping it out. So I could just pump out 10 gallons a minute continuously if I really wanted to. Okay, so once we lowered the pump down to 180 feet, the top is capped off with a cap, but also a valve that allows me to let the water come out or not. And I have an electrical wire coming out the top that goes over to a circuit breaker so I could... turn the pump on and off. And that's it for now. I'm using that to just fill water tanks for construction and our camper. When we actually hook this up to the house, I'm gonna dig long down alongside the casing about six feet and drill a hole in the side and put what they call a pitless adapter in the side of the of the casing. And the water is going to come out of that adapter and then out pipe underground below frost line to the house. The well is just gonna have a solid cap and there's gonna be no access to water. water out the top anymore. You're going to just access the water from the house at that point. Well, that about wraps up how we did our well here. If you have any information that I missed or was incorrect about, or just have your own stories about your wells, I'd love to hear them. Please comment below, and I'll see you all next time. Take care.

But on top of that is a certain amount of what you call overburden. Overburden is clay and sand. and gravel and boulders and water that's sitting on top of the bedrock. Now, in some areas, you'll see bedrock outcropping right on the surface, and there is no overburden at all where you see that. In other areas, there'll be hundreds of feet of overburden.

It really depends on geological processes that I really couldn't tell you much about. So you got to get through that overburden and down to bedrock, and that can be a variety of different types of rock. In my case, it happened to be shale.

So in order to get down to that water, you've got to drill through the overburden and into the bedrock and hit water. And, you know, in my mind, this whole thing, before we even started, I found this to be completely amazing. Because deep down inside, under the ground like that, that is like unknown territory.

It's like a frontier. It's like alien almost. It's like going down to the bottom of the ocean. I mean, we don't, you can't just go down to the ground.

I mean, there's all kinds of organisms and all kinds of things that like, you know, are totally foreign. to us down there I imagine. So I got really excited about the whole thing and when talking to different well drillers they started telling me all different stories like one of the coolest ones is when sometimes when they're drilling they'll actually all of a sudden the drill just goes just drops and a reason for that is because you can hit a cave.

They have hit caves that like are not accessible from the outside world. They're completely uncharted. There no one has ever been in them before and now we just broke a hole into them and you know it just Boggles the mind like you know what does that look like? So there are two main types while really there's one main type of drilling that's done around really surround here these days and that is A rotary drilling machine.

This is a giant machine on a truck. It's diesel powered and it has a hydraulic a giant hydraulic pump on it and What it's doing is it's it's a basically like a giant hammer drill if you're familiar with like a DeWalt hammer drill You might buy at Home Depot. It's spinning But as you apply pressure to the drill bit pushing up, it starts hammering, like hammering down.

The idea is it's fracturing the masonry that you're drilling into, or the rock that you're drilling into. And that is the exact same thing that's going on with the rotary drilling machine. So another method that's still used around here, although a lot less used, is the cable tool. And that is basically, instead of a rotary motion, it's literally just a big drill bit that is just lifting up and then slamming down and pa-pound, pa-pound, pounding.

into the earth and fracturing up that rock. We definitely gave each a lot of consideration and I'm going to cover that in another video. But we ended up choosing the common method nowadays, it is the rotary drilling machine. So this machine arrives on a truck, it's got a support truck that's filled with a couple thousand gallons of water and this machine has a giant boom on it that lifts up in the air, it's got a drilling head up on that boom that travels up and down about 20 feet.

And that is the head. that is spinning and that is hammering and then that's all hydraulic powered. To get started they get the machine all leveled out so it's got these feet that come down and level out the machine because if the machine is not level you're not gonna drill a straight hole down into the ground it's gonna be angled at whatever angle the machine is at. So once it gets leveled out they start the process by attaching the drill bit which is like this giant like tri wheeled grinding tool. So these little grinding heads I believe they spin bin and the drill head, the drill bit actually has holes in it that shoot out water and compressed air and I'm going to get to that in a little bit.

So the machine starts drilling. It sends down a 20 foot length of pipe. Once it gets there, a little collar is secured around the end of that 20 foot shaft to hold it from falling into the hole and then the drilling head, the power head, rises up 20 feet. and then there is a spindle that swings over and drops off another 20 foot shaft and is attached to the power head.

That comes down to the previous 20 foot shaft, and then it spins and threads it into the previous one. And then it goes down another 20 feet, locks in the pipe around the collar, and then the power head rises back up 20 feet, and again ...and until you hit bedrock. Once you hit bedrock, that's when the casing comes in. So the casing is a six-inch steel pipe that keeps all the overburden from falling in the hole.

It's necessary because the overburden is, um, it's sand and dirt. and mud and all these and gravel and that can just fall collapse and fall fill up this hole so we need something to to keep all that stuff out so we grab a piece of a 20 foot length of steel pipe and basically it's a very similar process to the the drilling. The same mechanism grabs it, spins it, pushes it into the ground. So each 20 foot length of casing has threaded ends.

So one side is male, the other side is female. So when they're connecting each of those lengths, they spin the top one onto the previous one that's already in the ground. And they thread it in, makes a tight connection. Then he comes back and arc welds it completely together. Because think about it.

You might have to go down, you know, maybe you're lucky you only have to go down. down 40 to 80 feet into overburden. Or maybe you're not lucky and you have to go down, you know, 100, 200, maybe even 300 feet of overburden before you get to the bedrock.

The spinning action that's pushing that casing down, there's a lot of friction against the sides of the hole, the drilled hole against the overburden. And you don't want to compromise those connections. So by welding it, by threading it and welding it, you're making a super strong shaft that just is not going to compromise. as you're pushing that casing down. The very first section of pipe that goes in, they attach a drive shoe to it.

So I guess that's like a, I don't know if it's hardened, but it's definitely like a thick piece of steel that just threads onto the bottom of that pipe. And the point of it is, is that once you get down to bedrock with the casing all the way down, basically what they turn on the hammer drill portion of the power head, and it actually just literally drills, pounds and drills that... drive shoe and thus the whole casing into the bedrock about eight to ten feet.

That drive shoe, if you did that with just casing, it would probably break up the steel. But the drive shoe is super strong so it's able to keep everything intact while that's happening. So now we're eight to ten feet into the bedrock. So we're locked in. All that overburden can't get into the casing now because we come out of the surface.

So nothing's gonna fall on the top and we're in the bedrock on the bottom. So we're sealed. We're sealed as far as the overall design is concerned. the overburden goes. Next thing you got to do is actually seal around the outside of the casing into the bedrock.

The hole that's being drilled for the casing is two inches bigger diameter than the casing itself. So that is what's creating. There's approximately like, you know, half an inch to an inch on each side gap that we need to fill up.

Because what we don't want is surface water ultimately making its way down through or really contaminated surface water, which is possible because we are. we are humans and we make a mess of things. It working its way down around the outsides of the casing and thus into the bedrock, contaminating the water supply.

So they would put in something called grout. That is, in my case, they used a bentonite clay, the powder like cement is, and they literally just dumped it in. And then, you know, water will mix with it and there is moisture down there and it will harden and totally seal up the outside of that casing.

I've seen some other cases where like they're purposely putting in more material to come up with. up all the way to the surface. My well driller said that a lot of the debris that comes out of the top of the casing as we're drilling into bedrock will fall in and fill the rest of the gap between the casing and the overburden. In my case, it turned out I had about 180 feet of overburden before we hit bedrock. The first 15 feet was some big boulders and it was gravel and a little bit of clay, silty stuff, but then it just turned into like solid clay.

The nice thing about that is that clay is not very permeable. It basically, since it's just like muck, it like oozed right in and suctioned itself to the sides of the casing. Which is good, because that's gonna help keep any kind of surface contamination from working its way down. to groundwater or even alongside the casing.

So in addition to the grout that the fact that I had like a hundred and whatever was 65 feet of just mucky clay is gonna seriously help keep any surface water contamination from ever getting down there. So with a rotary drill you know you've hit water. When literally water just erupts out of the hole. It was pretty violent actually. You got all that compressed air blowing all the debris and all the water used for drilling and cooling the bit and all that up out of that hole and you see that coming up.

It's you know, it's not too much. It's pretty consistent. Just a spray that's coming up. But when we hit water man, holy cow, it just blew right out of there. It's gushing and almost, you know, if you're standing in the right place, you would have gotten knocked over.

That is when we knew it was time to stop and assess the situation and I ended up with about 10 gallons a minute of flow in the end. Alright, so after you've got your hole drilled, your casing in, and you're drilled all the way down to the bedrock and developed a good amount of water flowing into it, into your well, it's time to drop the pump in. So I think they took inch diameter PVC and threaded it into the top of a 220 volt impeller pump meant for wells. And right down on the bottom of that PVC, right above the pump, they They got this blue thing, looked like rubber, and I didn't ask, but I believe it was to push against the sides of the casing or the bedrock, wherever they dropped it, and it's to keep the pump centered in the pipe. Could be wrong on that, so if I'm wrong, please correct me.

I imagine when the pump goes on, it's a pretty powerful pump, so it's probably going to want to move around a little bit, at least on startup. So that's just going to keep it in the middle instead of banging against the side of the hole. So, yep, up with that. They ran two 110-volt hots for the 220 and a neutral.

And they basically, similar to how they were doing the casing and the drilling, stick by stick, 20 foot lengths, they dropped the pump down and then connected the sticks of PVC to each other just by threading them. They have a male and female thread. So it's standard, I guess, PVC water pipe.

I don't know if this is drainage pipe or what. PVC is usually drainage pipe from my experience. This isn't under pressure. It's just a pump pumping up to a tank or another pump.

I'm not sure the details on that. pipe. Yeah, so in this case, you can do this by hand, but they had a truck with a little crane on it with a little attachment that has a collar on it that allowed them to hold the pipes vertically and they're able to, that's how they're able to thread them on top of each other and then lower them down together.

They went down 180 feet and that was not an arbitrary number. That tells you how far down the water is. Temperature is 72.4 feet.

It's going down. Oh, I see. Okay. So it's got like some type of sonar or something? It is sonar.

Yeah. Sonic sonar or whatever. Okay, cool.

So, let's take a step back. So the whole depth of the well was 325 feet. We hit water at 300. They went down another 25 feet. not exactly sure why I imagine it's probably because any sediment coming in from the water veins it has a chance to to settle down low but below where we hit water so it never clogs up down there but again Again, if I'm wrong on that, please correct me.

So then, when we drilled it, the pressure of those veins pushed water in and rose that water level in the well up to 52 feet below the surface. And that's where it leveled off. Then at that point you had enough weight of that water holding back that pressure.

So when we take water out and bring the water level down lower than 52 feet, it'll work its way right back up at about 10 gallons a minute, because that's the rate of flow coming into the well. So we dropped the pump down to 180 feet. So that's approximately 126 feet below the level of the water in the well, in the casing there. So if you think about that, you got a little bit over one gallon of water per foot of a six inch pipe or six inch hole there. You got about 126 gallons, maybe about 130 gallons sitting on top of that pump.

Now that's all the water that's ready to be pumped out. So yes, we have 10 gallons a minute, but we can pump out as fast as we want, as fast as that pump will let us. for that first 130 gallons.

So very rarely are we ever going to be pumping out 130 gallons at a time. Generally, you're pumping into your home, filling up a pressure tank, and your pressure tank is never really more than 20, 30, 40 gallons. So it's going to kick on in a normal house situation. It'll kick on, fill up that tank, and then kick off again.

So it can really just pump as fast as it wants. In my case, I'm probably not going to be using this well water as a primary source. It's probably going to be backup, probably filling up a cistern when we don't get enough. rain. I'll probably just limit the rate of the water flow and I can.

I got a valve, I got a adjustable valve here so I can just keep running it until my cistern is full without running out of that 130 gallons. But keep in mind also is that as you're pumping that stuff out new water is coming in so... You probably actually have way more than 130 gallons before you actually run dry get the water level down that far. So the rate of water coming into my well is around 10 gallons per minute. The rate that my pump can pump water out of the well is also about 10 gallons a minute.

So if you think about that, as I start depleting from that 120, 130 gallon reservoir sitting on top of the pump, the water from underground is refilling the well at about the same rate that the pump is pumping it out. So... I can never run out of water unless water stops coming up from the ground. I can pump out as fast as I want, and it'll just keep refilling as I'm pumping it out. So I could just pump out 10 gallons a minute continuously if I really wanted to.

Okay, so once we lowered the pump down to 180 feet, the top is capped off with a cap, but also a valve that allows me to let the water come out or not. And I have an electrical wire coming out the top that goes over to a circuit breaker so I could... turn the pump on and off. And that's it for now.

I'm using that to just fill water tanks for construction and our camper. When we actually hook this up to the house, I'm gonna dig long down alongside the casing about six feet and drill a hole in the side and put what they call a pitless adapter in the side of the of the casing. And the water is going to come out of that adapter and then out pipe underground below frost line to the house. The well is just gonna have a solid cap and there's gonna be no access to water. water out the top anymore.

You're going to just access the water from the house at that point. Well, that about wraps up how we did our well here. If you have any information that I missed or was incorrect about, or just have your own stories about your wells, I'd love to hear them. Please comment below, and I'll see you all next time.

Take care.

Transcript for:Overview of Well Drilling Techniques

Transcript for:
Overview of Well Drilling Techniques