Plugging a well for water. Plugging drinking wells

A cement (plugging) composition is introduced, after which it hardens within a few days. As a result, the solution turns into a stone - a monolithic "shirt" in which the casing is enclosed. Well cementing technology is complex and requires special knowledge and experience, and special equipment for cementing wells is used in the work. The work is carried out by several methods, depending on the purpose of the structure, the type of soil and the depth of the water veins.

The final stage of well drilling is cementing, this operation affects the entire performance of the structure

Why cement

Displace the drilling mud with cement, ensure the strength of the structure and bring it to working condition.

Well cementing has three main objectives:

Strengthening the casing;
Water pipe corrosion prevention;
Prevention of mixing water of different levels.

When pipes are filled with grout to abandon the well rather than putting it into operation, it is grouted, a process that differs from cementing. Although these are two types of work with differences in technological process, grouting and grouting equipment can be used the same.

Calculation of pipes for casing strings

Columns are needed to choose the right pipes: diameter, material strength and wall thickness. Depending on the technological operating conditions of the structure (geological structure, ground pressure and the possibility of its displacement), plastic or metal pipes are used.

When calculating the casing, the maximum values of internal and external pressures are used. The margin of safety will allow the use of the structure with the maximum possible loads in specific conditions.

Composition for cementing

Calculate pipe filling cement mortar it is possible according to the formula, using specific data: well depth, pipe diameter, annulus width. Also, the calculations take into account the coefficient (K 1), which indicates the consumption of cement slurry for filling cracks, cavities and errors in the diameter of the casing string.

A standard cement-sand slurry can be used for plugging wells that are arranged in a dense clay soil

The formula for calculating the amount of cement mortar looks like this: V c \u003d (π / 4) * [K 1 * (D 2 - d 1 2) * H c d 2 2 * h], m 3.

Due to the complexity of calculations, plugging operations, as well as the need to use professional equipment, technologically competent well plugging can only be provided by a well cementing center.

The composition of the solution is selected taking into account the structural structure soil layers. In order for the cement mixture to contact the pipe more closely, it must contain components that increase the volume of the solution.

If a preliminary study of the soil has shown that some geological layers have a porous structure, the use of conventional cement slurry is not recommended. The reason is that it will begin to penetrate into small voids in the thickness of the soil, and this is an overuse of grouting material. To avoid this, casing strings are cemented in such soils with the addition of fibrous components, such as asbestos, reeds and similar materials.

Components of the technological process

Cementing of wells is carried out in a certain sequence, regardless of the chosen plugging method, and is performed in five stages.

Preparation of cementing composition;
Filling the pipe with mortar;
Forcing the cement composition into the annulus;
hardening of the cement mixture;
Checking the quality of cementation.

Plugging is carried out according to a pre-compiled program, which takes into account the peculiarities of mining and geological conditions, the depth of the well or its separate part subjected to cementing, the condition of the wellbore and other design features.

The key equipment used in well cementing is a cement construction unit and a cementing machine.

If well cementing has already been carried out in the area, the calculations and plugging process can be based on already existing experience, but with a correction for new technical data.

Methods for pumping cement slurry into the annulus

The introduction of cementing material into the annulus is carried out according to two schemes: reverse and direct methods. Cementation of the annular space in the reverse way is carried out by pouring the mixture directly between the pipe and the soil. As the space is filled with grout, the drilling fluid is forced out through the lower end of the pipe.

The direct method, in turn, is divided into different ways well cementing, and each of them is applied depending on technical capabilities and the goal to be achieved by cementing.

The main methods of the direct plugging method:

Single-stage cementing is performed in one pass. The full volume of the cementing composition is prepared, introduced into the pipe and covered with a cork. After that, the flushing fluid enters the well, the plug slowly lowers and squeezes the cement out of the pipe;
Two-cycle, or two-stage cementing of wells is carried out if, for technical reasons (large depth), preparation of the full volume of the solution is impossible. With this method, the process is carried out in two steps: first, the lower part of the annulus is filled with cementing mortar, and then the upper one. The second stage of work can be carried out with a significant time interval after the final setting of the first portion of the solution, or immediately, without a break in time;
The sleeve cementing method is used if the lower section of the pipe needs to be isolated, and only the upper section of the well is subjected to cementing. A cuff ring is mounted between the casing string and the soil, and grouting materials are injected into the space above it through the holes in the pipe.

Cementing equipment

The technological process cannot be carried out without specialized equipment. These are bulky mechanisms that are available to the well cementing center.

Equipment for plugging works:

Mixing machines for mixing mortar;
Cementing mechanisms for pushing the solution into the hole;
cementing head
Fill plugs.

In addition, other tools and devices are used that play an auxiliary, but no less important role in cementing. These include hoses, pressure gauge and high pressure taps, vibrators and more. The equipment is transported on the platforms of trucks, and the engine of the machine is used to start and work with it.

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Plugging of horizontal wells

Plugging of horizontal wells is much less common. They have a more complex device, as they include elements of vertical and inclined structures. In economic terms, the construction of horizontal wells is 3-4 times more expensive than vertical wells, therefore, the technology of plugging horizontal pipes should ensure maximum reliability of the cement "jackets" of casing strings and the duration of operation of the mine. For it to be profitable, it is necessary that the income from production exceeds the funds invested in its creation.

Cementing of wells, or as it is also called plugging, is one of the most important stages of their construction, and this applies not only to oil, but also to water intake facilities.
The essence of this operation is that the space formed between the walls of the pipe and the penetration must be filled with cement mortar. That's what we'll talk about in this article.

All about packing

Cementation of deep wells is carried out taking into account the experience of previous years, with the help of modern equipment and scientific research. Typical schemes The production of these works has been worked out to the smallest nuances, and their competent implementation is very important.
Firstly, the tampon prevents pressure water and quicksand from affecting the wellbore, preventing them from washing out the shaft. Secondly, the solidified solution rigidly fixes the structure, preventing the columns from moving.
So:

Wells are plugged (see) not only during the construction process, but also during conservation and liquidation - only the technologies are somewhat different. Although, absolutely everything is impossible to take into account, since in each case there are different conditions works: technical equipment, well design, geological conditions, the length of the cement bridge.

Therefore, technologies are often refined in the course of work, and this is normal.
The main thing is that this process provides the following requirements:

To meet these conditions, it is necessary to control and adjust the characteristics of the flushing fluid in order to reduce its viscosity. Recall that flushing is carried out during the drilling process, which allows you to soften the soil and wash out the cuttings from the penetration.
The cement slurry is injected into the annulus at a rate that can provide a turbulent regime.
In each case, the formulation of the solution is selected individually. Its properties determine both the duration of plugging operations and the modes of injection and punching of the solution.
By the way, ordinary building cement is not used in this case. There is a grade specially designed for wells, which is called "gypsum alumina cement."

It tends to expand, and this is the most important thing in plugging work. A solution of such cement is not absorbed into the soil, but fills all the voids and the smallest cracks, clogging them according to the principle of a tampon - hence the name of the technology.
If there are large voids and quicksand in the penetration, dolomite flour, bentonite clay, or asbestos or cellulose fibers are added to the gypsum-alumina solution.

One-cycle plugging, with two plugs

When cementing using this method, the bottom plug is first installed in the desired wellbore segment. It has a channel for the passage of the solution, which is temporarily blocked by a diaphragm.
Further, a head is installed in the upper part of the column, through which the cement slurry is supplied from the mixer. The top plug, held in place by studs, is positioned on the cementing head.

So:

When, according to the calculation, the entire volume of the solution is completely pumped into the barrel, this plug is released, and the flow of fluid for punching begins. Under high pressure, the mass of the cement column, along with the cork, moves down.
Along the way, it displaces drilling fluid from the wellbore. This happens due to the own weight of the cement slurry, as well as its high density. In the process of liquid displacement, the pressure level on the head through which the solution is injected is significantly reduced.

The plugging mixture column moves along the shaft together with the plug installed at the bottom mark. And as soon as it stumbles upon the thrust ring, there is a sharp increase in pressure.
As a result, the jumper diaphragm, which blocked the hole, is destroyed. After that, the solution freely enters the annular sinuses.
The volume of fluid pushing through the cement plug is continuously monitored, and when the last couple of bottoms remain, the pumping rate is reduced. As soon as the plugs that cut off the interval come into contact, as evidenced by a sharply increasing pressure, the injection of the cement mixture stops.

Two-cycle cementing

In this way, two intervals are sequentially plugged at once. Compared to single-cycle cementing, this method has some advantages.
At the same time, the probability of penetration of the flushing liquid into the cement mortar is significantly reduced, and the pressure on the soil during its lifting is reduced. Importantly, the lift height can be increased significantly even if the pressure does not increase.
So:

The preparatory work preceding plugging is carried out according to the same scheme as mentioned above. Only now, in the lower part of the segment of the casing, which is being prepared for plugging, is the casting sleeve installed.
At the end of flushing, the head is installed, and the pumping of the volume of cement mixture that is necessary to fill the first stage begins.

At the next stage, an intermediate plug is introduced into the wellbore through the filling sleeve, which completes the first cycle, and, under the influence of the displacement fluid, moves the injected mixture deep into the hole. Its quantity, at the same time, is equal to the volume of that segment of the casing string, which is located between the thrust ring and the filling valve. Then, the bottom plug of the second segment, which is located in the body of the cementing head, is released and forced through.
Under the influence of pressure, the plug will be pressed against the sleeve, it will sit on the sleeve, and, moving down, will open the through passage. There are two options for further action.
In one of them, after the completion of the cementation of the first stage, they immediately begin the second cycle. This method is a continuous cementing process.

The second option is called: two-cycle plugging with a gap. In this case, the pouring of the second section of the column is carried out only after the already pumped cement mixture has set.
During this period, drilling fluid circulation is maintained in the filling valve. This option allows you to adjust the level of dynamic pressure that occurs in the annular sinuses, and, accordingly, improve the quality of plugging.

As soon as the supply of the calculated volume of the cement mixture intended for the second segment is completed, the last, upper plug is installed in the column and forced through with liquid. Now she, moving down along with the sleeve, will block the through hole.

Sleeve and reverse cementation methods

The decision in favor of the collar method is made in cases where the formation is cemented at low pressure, or it is necessary to prevent the entry of the solution into the filter column. Its essence is that at the lower mark of the plugged sector, a sleeve is installed with holes for the passage of the solution, and a tarpaulin cuff.
So:

A valve is located just below the sleeve, blocking the access of the solution to the inside of the column. And the cuff, in the process of injecting the solution, covers the annulus so that the cement column can only move upwards.
There is another option in which cementation is performed in the opposite direction (from bottom to top). In short, it is done like this: the casing along the lower perimeter is covered with a special shoe; the solution, through a special sleeve, is pumped directly into the annulus.
At the same time, the drilling fluid located there is displaced, and, through the casing pipes, comes to the surface.

This method attracts drillers, but it is not suitable for cementing ultra-deep wells. The reason for this is a number of technical difficulties.
For example, it is difficult to control when the cement slurry reaches the bottom of the casing string. Accordingly, it is also impossible to assess the quality of cementation - and this part of the wellbore is the most critical.

The final stage of cementing

The hardening period of the cement column may vary, depending on the composition of the mortar. It also matters which column was plugged.
For a conductor, for example, 16 hours are enough, and for a production string, a day is needed. After this period, an electrothermometer is lowered into the well.
So:

With its help, by temperature changes, determine the height of the rise of the solution in the cemented space. The maximum release of heat by the solution occurs within a few hours after its hardening.
Therefore, to determine this indicator, the device must be lowered into the well within a day after the end of plugging.

An acoustic probe (borehole locator) is widely used to control the quality of cementing. Areas not filled with a solution are determined by the amplitudes of sound vibrations. If there are no complaints about the quality of plugging work, the wellhead is tied up.
Then, a pointed chisel or a bailer is lowered into it, with the help of which the hardened solution residues and filling plugs are drilled.

Next comes the turn of pressure testing the barrel, that is, checking it for tightness. For this, water is pumped into it at a pressure exceeding the calculated one by 20%.
If, after half an hour, the pressure drops by no more than 0.5 MPa, and there is no gas evolution and no water overflow, the well is considered tight.

Well plugging is a set of measures aimed at protecting the subsoil and strengthening the annulus and casing from the damaging effects of rock and groundwater. Many readers who begin independent drilling are often interested in whether plugging a well for water is necessary, and how to do it on their own.

We will try to answer.

Well cementing

Purpose

Let's start by defining the term itself. Plugging is the filling of rocks and the cracks present in them with cement mortar to prevent the seepage of water, oil or other minerals through the rock and the penetration of these substances into other layers and horizons of the soil.

Distinguish:

direct cementing of the annulus of wells in order to strengthen the wellbore and prevent leakage of perched water and groundwater into the limestone layer;
cementing for the purpose of abandoning a well - abandonment plugging.

Liquidation is needed due to the fact that in some cases an old well begins to pose a threat of contamination of aquifers. Artesian water reserves are considered strategic reserves of the state, so their security is the security of the country.

On the basis of analyzes and examinations, the competent authorities decide on the need for liquidation plugging of the object, then draw up a project of work, and, after its approval, cementing is carried out by professional organizations.

Important!
Production cementing makes sense only in the case of a large depth of the well and certain characteristics of the cut of the rock.
For drilled wells “on the sand”, this measure does not make practical sense, since in this case there is no danger of communication between different aquifers.

When drilling artesian wells, the decision on the need for cementing is made by the organization performing the work.

When is tamponage needed?

To concretize the article, it is necessary to immediately determine the signs by which it is possible to establish the need for cementing and abandonment of the well.

So, plugging is necessary in cases where:

The quality of the water in the well has deteriorated, and restoration or improvement is impossible or impractical due to technical, physical or economic considerations;
The object has exhausted its resource and is no longer in operation;
Temporary wells of small diameters are no longer of interest due to the emergence of other sources of water supply;
Defects in the design of the facility are found, the flow rate has decreased or an accident has occurred, and the restoration is economically unprofitable or technically unfeasible;
Geological exploration or exploratory drilling has completed its task and is no longer needed;
Springs with pressure gushing waters ceased to be constantly exploited;
Absorbing wells began to pose a threat of contamination of aquifers.

It should be said that plugging is most often performed when drilling oil and gas developments. When water is extracted, objects are rarely cemented, in special cases.

There are no clear rules here when concrete should or should not be made, everything is decided in the process of designing and performing work on the basis of intelligence data, the structure of the rock cut, its composition, etc.

In practice, everything looks like this: after drilling is completed, the owner of the well receives a passport for the object, which indicates exactly how to monitor him and what measures to take in certain circumstances. Among other things, it says that in the event of an accident, breakdown, deterioration in quality and other force majeure circumstances, the owner is obliged to notify the SES.

Further, the SES takes water for analysis and inspection of the facility. Based on the data received, the station issues a verdict on the state of the well and its future fate, and the owner receives instructions for actions that he must take to eliminate the breakdown or object.

Important!
The responsibility for the correct implementation of all prescribed measures lies entirely with the owner, and failure to comply with these requirements threatens with criminal prosecution for violating the law on subsoil protection.

Work on proper plugging is carried out using special equipment, the price of which is unbearable for a private person or a summer resident. Therefore, many are interested in whether do-it-yourself cementing is possible? There is no single answer here, it is necessary to consider each individual case.

Installation

For owners of private homemade wells, you should be aware that their Abyssinian wells and sand wells do not need cementing. This is explained very simply: these objects do not pose a threat of contamination to stocks fresh water, since they do not cross different aquifers, but draw groundwater from a sandy aquifer.

However, another danger remains for such objects: perched water and sedimentary water can penetrate along the casing string or needle into the sand layer and contaminate ground water, reducing the characteristics of the source.

Preparation of a well for isolation works - A complex of geophysical studies is carried out in the well and the nature of the distribution of the filtration properties of the plugging interval is determined. The most and least permeable sections of the section are determined and ranked as the filtration properties deteriorate. Evaluate the performance of pumping equipment used in plugging or cementing. An express test of the well is carried out and the coefficients of permeability and filtration of rocks in the plugging interval are determined. Determine the injectivity of the most permeable interval and the maximum allowable plugging interval T taking into account the specified performance of pumping equipment:

Where Q - pumping performance; c - dynamic viscosity of the cement slurry; kmax - maximum rock permeability coefficient in the plugging interval; R - overbalance for the developed tool, taken equal to 0.8-i MPa; r0 - well radius; L - the specified penetration depth of the cement slurry, selected taking into account the design of the well, the requirements for environmental safety and reliable separation of horizons, taken at least 0.2-0.3 m.

Then, the plugging interval is distributed into sections with a certain thickness and they are ranked in order of deterioration in the filtration properties of rocks by serial number starting from one.

Tool Assembly- The discharge branch pipe, equipped with blades and holes for the output of cement slurry, is connected at both ends with drill pipes so that the total length corresponds to the length of the plugging interval L= m, and the discharge pipe was located in the middle of the tool. Usually, L= 5^7 m.

From both ends of the pipes, sections of jet nozzles are screwed, directed towards each other, towards the discharge pipe. Sections of augers or turbulators are connected to sections of jet nozzles, and to the lower section - with the right winding, and to the upper section - from the left.

The total length of the sections installed augers or turbulence

The blockage is calculated in the near-wellbore zone, based on the need to create a turbulent filtration mode for the cement slurry:

Dp = Kb Cr, (6.89)

144(1 - a)2k2pg

Where K, etr are the critical values of the Reynolds number (K. etr = 0.1); A- porosity; L - predetermined depth of penetration of the solution into the formation; K- coefficient of permeability of plugged rocks; p is the density of the solution; G- acceleration of gravity.

Given that jet nozzles create an average pressure drop on the formation of 0.5-0.6 MPa, the length of the sections of augers or turbulators

1= [D R - (0,5 4- 0.6)MPa]b

P(02n (tr + F) sin2 in™

Where L- length of sections of screws or turbulators; B- the length of one stage of the screw or turbulator; u - tool rotation frequency; P - number of turbulator blades or auger spirals; ytr- diameter of the pipes of the discharge branch pipe; exit of turbulator blades or auger spiral; in - the angle of inclination of the screw spiral to the horizontal.

In order to reduce the bulkiness of the tool, the rotational speed is taken to be the maximum possible, based on the power of the drilling equipment at a given depth of the plugging interval.

Running the tool into the well and injecting the solution. The tool is lowered into the well on drill pipes and fixed against the most permeable interval. A grouting slurry is prepared on the surface, which is then pumped into the drill pipes and through the jet nozzles into the isolation interval. At the same time, the tool is rotated at the highest possible frequency.

Upload time

T = CW, (6.91)

Where With- reliability coefficient (с = 1.3^1.5); W- the volume of the plugged zone, W = 0.785(L2 - r02)4l; Q - performance of pumping equipment.

After pumping the estimated volume of the cement slurry into the reservoir, the pump supply is stopped.

The tool is moved, without stopping rotation, to the next plugging interval, which is characterized by the worst filtration properties. The solution is pumped and the next interval is isolated in the sequence described above. It is possible to pump well-mixed solutions through the drill pipes by a pump with a nozzle, the size of which does not exceed half the diameter of the nozzle of jet nozzles, which is usually 2-3 mm. Larger additives are loaded into the well annulus and then transported by the left auger or turbulator to the isolation interval.

In highly absorbing rocks, it is rational to alternately pump cement slurry with portions of air. To do this, an aerator or a dosing device is installed in the discharge line after the pump. Subsequent intervals are equipped by analogy with the technology described above.

Final work- After the cement slurry is pumped into the specified interval, the pump is turned off and the wellbore is calibrated with the tool rotating and moving up and down along the isolation interval. The tool is moved until the hardened solution begins to prevent the collapse of the walls of the well and the flowing of the semi-hardened mass of the insulator. The instrument is then lifted to the surface.

Before running the casing string, caliper measurements are carried out, the diameter of the wellbore in the isolation interval is determined. If necessary, the trunk is worked out with a chisel. In some cases, the casing may not be installed. The quality of insulation work is controlled during pressure testing of the barrel (liquid absorption is monitored). If the well absorbs fluid in the plugging interval, then the quality of work is unsatisfactory and repair work is needed.

If the quality of the primary cementing is unsatisfactory, the express testing of the well is repeated, the mud loss intervals, the filtration coefficients of the rocks in the near-wellbore zone after the primary plugging are determined. Re-plugging is carried out and the remaining permeable intervals are isolated in the sequence similar to that described above.

After completion of the work, the insulation quality is re-checked by the express method and, in case of an unsatisfactory result, the composition of the cement slurry and filler is changed. If necessary, a casing string is lowered into the interval, which is then cemented.

Well plugging is used to protect underground water sources from dirt. It includes a set of works to prevent a negative impact on water when the well is shut down.

There are several types of wells, so the owners ask the question, what is plugging a well for water, what is it, and how is it carried out. In our article, we will consider the tamponing procedure.

When plugging a well, the process fills the cracks with rock, but cement can also be used. Such a procedure is required in order to prevent water and oil deposits from entering the structure. In the course of work, it is required to supply binder solutions behind the casing pipe, but they can also be fed directly into the wellbore.

At the moment, there are several types of plugging, which we will consider.

The first type is to protect the structure from the penetration of water from the ground or perch. This method is used when plugging the casing string.

plugged well

If it is required to completely eliminate the well, liquidation plugging is performed. For this procedure, the most effective method is cementation. It is necessary to carry out if the object poses a threat to groundwater, this procedure is mandatory for the plugged water intake facility. As a rule, old wells are liquidated so that their functioning cannot contaminate artesian water. A special place is occupied by the plugging of an artesian well. It is carried out only by professionals, there is a strict procedure, since artesian water is a strategic state reserve. In case of violation of the requirements, the perpetrators are liable in accordance with the law.

Before making a decision to plug a well, it is required to conduct research by the relevant services, which will make a conclusion about the need for plugging. For this, an act is drawn up, then a draft is prepared, which is approved. When the necessary documents are prepared, the plugging procedure is performed. You need to entrust this work to professionals

If an artesian well is being equipped, the decision to liquidate it is made by the organization that performed the work during drilling.

Operational plugging is used only in cases with deep wells.

When is tamponing required?

Design work is preceded by a decision on the need for this procedure. This decision is made if there are the following signs:

poor quality water, but if work is carried out to restore the well, this will not bring the desired result or there will be no effect at all;
the debit of the well is minimal, so further operation is impossible;
temporary structures are subject to plugging, the need for which has disappeared, since water is taken from other sources;
an act was drawn up that contains information about defects in the design that cannot be eliminated, they caused a decrease in water quality, productivity decreased, or it is not financially feasible to eliminate defects;
for prospecting and geological exploration work, temporary wells are made, which are subject to mandatory plugging after the need for their functioning has disappeared;
the flowing well is not used;
plugging is also carried out in the event of a threat of accumulation wells, the liquid from which can penetrate into the water veins.

What are the benefits of plugging wells

At the moment, there is no such effective way to protect aquifers from pollution. Plugging minimizes the risk of deformation and depressurization.

There are situations as a result of which low quality water penetrates into the artesian layers. By sealing, this threat is eliminated, pure water isolated from the source of pollution.

In some cases, the plugging procedure is carried out in order to achieve additional insulation of the structure.

Well plugging scheme

What is used for plugging and how the work is carried out

The well cementing process is preceded by a calculation procedure. This approach allows you to correctly calculate the amount of materials needed for the work. The composition of the mixture is also calculated, and how the supply will be carried out. When performing analyzes, some data are taken into account. We are talking about the depth of the well, what is the distance between the casing and the walls of the well. They consider the shape of the penetration, whether there are violations in the structure that appeared during the installation of the hydraulic structure. Take into account the composition of the soil, hardness.

In the event that some time in this area drilling has already been done, then you can use the information from this project. If you correctly carry out the calculations, then the cementing of the well will be as efficient as possible, the consumption of materials will be correct (in this case, save money). It will also help to correctly carry out the procedure for competent drafting of the project.

You need to understand that if you decide to plug the well, then this process is irreversible, it will be impossible to restore the operation of the well. It will also be impossible to correct the mistakes made in the process. That is why it is better not to carry out this work if you are not confident in your abilities and knowledge, but to entrust the work to specialists.

When carrying out the procedure, the composition of the soil is taken into account. This is necessary in order to correctly select and calculate the amount of solution. The most common is a solution of cement and sand. It is best suited for a well located in dense clay soil. The basis in this solution will be Portland cement. It is used because it allows to achieve excellent mobility of the solution, thereby allowing the supply with a pump. It dries very quickly and has a high level of strength.

Asbestos, paper, and other fibrous materials are widely used in plugging in porous soils. If you still decide to use ordinary cement and sand, then in the process of work you may end up with an increased consumption of material, which will increase the financial costs of the procedure.

In some cases, the use of foaming compounds is allowed. In the process of solidification, they expand. They increase the sealing performance.

It's a good idea to add sand and gravel to the mix. But these materials should not be very much, it is important that such a solution remains liquid. To disinfect, bleach is also added here.

Training

On the preparatory stage preparing documents. As we have already said, this is an act and a project. The project must be coordinated with the sanitary service. All responsibility lies directly with the owner. He must ensure that all work is carried out in accordance with the project. That is why every well owner who is going to carry out plugging should know how it is done. Acts and technical reports are submitted to the sanitary service and public utilities upon completion of work.

Procedure

To date, there are several effective ways tamponing. One of the most common and simple is pouring a solution of cement and sand inside. The solution goes down and fills the space. But the effectiveness of this method is not the best. There are more effective, but complex ones.

In the case of back plugging, the solution is fed into the well. It penetrates the walls and rises to the top. This method is more efficient, but also more difficult. It requires the use of a special liquid that is supplied under pressure so that the solution can rise up. If conventional plugging can be done by yourself, if you know exactly the technology, then only a specialist should do the opposite.

Deep wells are plugged using a multi-stage technology. In different areas, they are tamponed in turn.