How to Drill a water well with the PORTADRILLMINI ®DRILL
The average minimum depth of all domestic water wells is slightly less than 50 feet! Basically, a water well is a hole or shaft down to a water-bearing layer of sand or gravel, void or a crack in the rock. Fortunately for the well driller, most of the clean fresh water beneath the surface of the ground occurs within 200 feet. Unless your area is very high elevation, famous for deep dry holes, the chances are that by a little investigative drilling you can find a useful water-bearing strata at a reasonable depth.
Where Will You Find Water?
Water saturated areas can be found around the immediate locations of streams, lakes, rivers , ponds , canals , sloughs and marshes . All underground water originates on the surface of the earth. The heat of the sun evaporates it; it forms clouds and falls as rain or snow; it accumulates in streams, ponds, oceans, etc.; it seeps into the ground. There is 30 times as much water underground as there is in all the streams, lakes, ponds, canals and rivers in the world!
In the ground, water is found in 3 general types of formations:
1. Layers of sand
2. Layers of gravel
3. Porous rock, voids or cracks in rock (fractures)
There is no single "best" source. Some folks have the idea that the deeper you go the better the water, or only "good" water comes from rock, but this is not true. In fact, some rocks have natural minerals that dissolve in water; stain, leave undesirable deposits and these minerals give the water an odd taste and sometimes an odor. Minerals such as iron, sulfur, lime . as last resort they can be removed by a good water filtration system . As a general rule, the finest quality water comes from layers of sand, which filter the water naturally. You will frequently hit layers of sand and gravel before you hit solid rock. In other words, the deepest water is not necessarily the most and the best. BY STOPPING ... at a decent looking water level with good flow, visually pleasing clean water within meeting your acceptable gallons per minute requirement criteria, may be best . Going deeper ...may just ruin the well by undesirable deposits or minerals. Who knows.. You can't see what is below the ground.
In the old days a man dug his own well and took the work chore more or less for granted. Wells dug by a pick and shovel, and is hard work and more than a little dangerous. There is always the risk of cave-in or asphyxiation. Still, a lot of water wells around the world constructed with simple tools and manage to get enough water to sustain life.
Today the most modern well drilling method is the rotary air method. It is fast and efficient but until recently it was only available in big, heavy, truck-mounted conventional drill rig models. The rotary drill consists of a rock cutting drill bit attached to a length of hollow drill steel. The drill steel and bit are rotated and by injection methods drilling fluids are pumped through the drill steel. The bit cuts into the earth and the water washes the cuttings out of the drill hole to the top of the ground. Additional sections of drill steel are added as the bit goes deeper.
How To Know When You've Hit Water?
In a rotary air/mud/ water injection drilling system such as the PORTDRILLMINI® DRILL, a rotating bit cuts away material at the bottom of the well. By method of injection drilling fluids or air is constantly pumped down the well to flush out the cuttings. This rotary system of drilling provides indications, which will let you know when you may have hit water.
The most important indication to watch for is the type of cuttings being flushed from the well as you drill. When you see coarse, pea rock, gravel-size pebbles coming up, you may be drilling into a water-bearing strata.
Another good indication can occur when you shut off your injection valve to change a drill steel: if the water in the well recedes quickly down the well, you may have reached a water-bearing strata. OR can indicate that the well walls collapsed on and round the drill steel causing a "bridge" in the well preventing the water to drain down into the well.
Because the ground water can be 20-30 degrees warmer or cooler than the drilling fluid and outside air there is a sudden change in the temperature of the drilling fluid when a water bearing strata is encountered.
When you have drilled down five feet, shut off the injection valve and add the next section of drill steel.
From two years of research and development safety features are incorporated in the design of the PORTADRILLMINI ® DRILL, and operators are cautioned against modifying the components of the drill unit. As with any water well drilling equipment, normal safety protection and practices are required. Do not fuel a hot engine. Keep long hair and loose clothing away from the moving parts.
WARNING: Take the required time to check for underground utilities . Do not drill near underground tanks or pipelines. Beware of overhead obstacles and electric lines.
The PORTADRILLMINI ® DRILL System U.S. PATENT # 6315059
Is a complete man portable, compact one-person well drilling system! It can be maneuvered into locations where conventional truck-mounted drill rigs cannot go. For example, it can be used in confined locations, or to drill in backyards where large truck drills would tear up the landscape. It can be maneuvered into wooded areas or hilltops or by helicopter to remote locations where it would be considered impossible to drive a truck because the roads are not adequate enough to sustain a large truck drill rig or simply don't exist .
The PORTADRILLMINI ® DRILL system makes it ideal for people with no prior experience in well drilling. The portability advantages of the system makes it possible to have water wells where ever you need them, not just where you can afford to pay a drilling contractor to drill.
With one PORTADRILLMINI ® DRILL, you can drill many wells repetitively. If you are drilling near an existing water system, you can frequently use water from the garden hose to assist in injection methods. Otherwise, you will need at minimum a 5 h.p. trash pump or mud pump and access to 50 to 150 gallons of drilling water to re-circulate the water.
Water Pressure
A & D Drilling Supply Corporation can supply you a pump that is designed for the job. It will handle abrasive sandy water, and will allow the use of additives to prevent cave-ins when drilling in sand or gravel strata (more on that later). You will need 10 to 20 gallons per minute at 20 to 40 psi..
To use the well drilling pump, dig a small pit next to the drill hole and fill it with water. Use the pump to draw the water out of the pit and into the drill steel and bit. As the water flushes back up the hole, channel it into the pit to be re-circulated. This way, you drill your well using a minimal amount of water. As a starter, have on hand about one gallon of water for each foot you expect to drill. A 30-gallon plastic bag in a trashcan makes a good container for hauling water to a drill site. Two or three 30-gallon bags should provide enough drilling water for most locations.
The circulation of water keeps the hole clean by washing the cuttings to the surface; this also allows you to examine the cuttings and identify the material from each level of drilling. These cuttings can tell you when you have found water.
Maintaining good water circulation while you drill is the most important factor in successful drilling. Failure to maintain good water circulation can cause bit failure and other problems. If at any time you lose circulation, stop drilling and pull up at least one drill steel section until circulation is restored before you continue to drill deeper. WARNING CONTINUING TO DRILL DEEPER WITHOUT CIRCULATION MAY CAUSE THE DRILL BIT AND DRILL STEEL TO BECOME JAMMED AND STUCK !
Bits
Next to diamond, tungsten carbide is the hardest substance in the world. In industry, tungsten carbide is used to cut hard, tough materials such as glass and steel.
There are three basic bits to perform three basic functions:
DRAG BITS : The Heavy Duty DRAG Bit is used in drilling earth, sand, clay, gravel and some softer rock formations. Unless you run into a layer of hard, solid rock, you should drill to the total depth of the well with your DRAG BIT .
Tri-cone Bits (also known as roller cone bits): The Tri-cone drill bit is used in solid rock. The long toothed, tungsten carbide tipped bit is used in most sandstone, limestone, coral, granite and some lava rock formations that have favorable cutting characteristics.
TCI TRI-CONE BUTTON BITS: Tungsten carbide ,insert, button, bits, designed for harder rock formations such as granite.
Drilling Hints
Occasionally, you may encounter a stratum of sand that tends to cave in on the drill steel. Or you may drill into an extremely porous stratum that causes a loss of circulation. In this event, you will need to pre-mix a thickening additive with your re-circulation system or use foam injection methods.
There are two types of thickening agents. One is bentonite clay called "drillers mud." The other type of thickening agent is a gel that forms a viscous fluid the consistency of buttermilk. These products are most effective when mixed together in your injection drill fluids.
Removing The Drill Steel
As long as proper circulation was maintained for the full duration of the drilling process the drill bit and drill steel can easily be lifted from the hole. Each bit is designed to cut a hole that is larger than the bit itself. If the drill steel does not turn freely by hand then the well did not remain open and can possibly be jammed with well cuttings, or worse collapsed.
A word of caution when removing the drill steel: WARNING
ALWAYS WATCH OUT FOR OVERHEAD POWER LINES AND OTHER OVERHEAD OBSTACLES!
It is never advisable to remove more than 1 sections (5 feet) of drill stem at a time.
WARNING
ALWAYS WATCH OUT FOR OVERHEAD POWER LINES AND OTHER OVERHEAD OBSTACLES!
It is never advisable to remove more than 1 sections (5 feet) of drill stem at a time.
The Well Completion
After you have drilled down and found a promising formation. Now you "case" the well, which simply means inserting a casing (metal pipe) to keep the well from collapsing at some future time. At the bottom of your well, you will use a "well screen" or strainer to keep the sand and gravel out of your well.
To increase the full potential of volume of this well solid casing is joined to the well screen and continued all the way to the top. Some small pea gravel is poured on the outside of the pipe to within 20 feet of ground level. The pea gravel helps filter the sand out of the water before it enters the screen and casing. It also serves as a conduit or passageway for water from a stratum above the screened area to work its way down to the screen filtering through the gravel pack all the way.
If you drill through a water-bearing stratum along the way and don't notice it, you haven't cut off the supply from the stratum. This is why we recommend only one section of screen and a good gravel pack. The top 15'-20' of your well must be sealed around the outside of your casing to prevent ground water contamination.
Cleaning The Well
Before you install the permanent pump on the well, it is necessary to clean out any cuttings remaining inside the casing. Much of the material can be flushed out by test pumping the well with a gasoline water pump or by dropping a water hose to the bottom of the well and pumping clean water through it. Because this is a shallow depth pump, it may be necessary to add clean water to the well as you pump to maintain an artificial shallow pumping depth.
If you have an air compressor, the well can be circulated - flowed with air. This will not only clean out the well, but will give you a good idea of the water production of the well. The well needs to circulate and flow to remove the cuttings and or residuals of drilling additives. This "circulation " is the term "developing a well," it gives the water vein a chance to open up and flow more freely. Just about every new well will improve in both quality and quantity of water after a few hours (or even a few days in some cases) of pumping.
More Information
Much has been researched about water well drilling -find an underground vein or strata of water and dig or drill an opening to it. When you see fresh, clean cool water pouring out on the ground, you will realize that whatever effort of labor you made to get it was meaningful. Water is life! To control one of the elements of life makes the thrill of discovering water an experience hard to equal!
To view the PORTADRILLMINI Drill in action drilling through rock see the video link.The link for the video is mms://media.engr.psu.edu/rth_net/drill_june2006.wmv
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