Building codes and regulations. Building codes

Appendix A (recommended). Calculation of water-reducing (drainage) systems Appendix B (recommended). Design of water-reducing devices Appendix B (for reference). Letter designations

Set of rules SP 103.13330.2012
"SNiP 2.06.14-85. Protection of mine workings from groundwater and surface water"
Updated version of SNiP 2.06.14-85
(approved by order of the Ministry of Regional Development of the Russian Federation dated June 30, 2012 N 269)

Protection of mines against ground or surface water

Introduction

This set of rules contains requirements that correspond to the goals of technical regulations: Federal Law "On Technical Regulation", Federal Law "Technical Regulations on Requirements fire safety", Federal Law "On Energy Saving and Improving Energy Efficiency and on Amendments to Certain legislative acts Russian Federation" and the Federal Law "Technical Regulations on the Safety of Buildings and Structures".

The updated version of SNiP 2.06.14-85 was made by the team of authors of JSC "Fundamentproekt" consisting of: Ph.D. tech. Sciences B.S. Smolin - theme leader, engineers V.V. Shilov, K.N. Savelyev, T.V. Bakharev with the participation of: Moscow State University. M.V. Lomonosov (candidate of geological and mineralogical sciences M.S. Orlov), NIIOSP named after. Gersevanova (A.B. Meshchansky, Candidates of Technical Sciences V.N. Korolkov, M.N. Ibragimov, O.A. Shulyatyev), OJSC "VIOGEM" (Candidate of Technical Sciences Yu.I. Volkov), OJSC " Anti-karst and coastal protection (candidate of technical sciences V.V. Tolmachev), LLC "ECOTIM" (candidate of technical sciences M.S. Divovich), FSUE "VSEGINGEO" (doctor of geological and mineralogical sciences V.A. Baron).

1 Application area

These standards apply to the design of protection from groundwater and surface water (hereinafter referred to as protection) of mine workings using water reduction, dewatering, anti-seepage curtains and regulation of surface flow during open-pit and underground mining of solid mineral deposits.

These standards do not apply to the design of the protection of mine workings located under water bodies, which include: sea areas, lakes, reservoirs, rivers, canals, swamps, hydraulic dumps, etc.

4.6 The design documentation should provide for the phased implementation of the designed protection system.

It is recommended to coordinate the terms of reference for engineering surveys with the authors of the design justifications for the protection system.

In conditions where, based on survey materials, it is not possible to make sufficiently substantiated calculations or to finally select a protection system, the design of its structures and devices, the design documentation should include experimental production work, the results of which are used to adjust the design documentation.

4.7 Using calculations and numerical modeling, the following should be determined: a decrease in groundwater levels at characteristic points, the time to achieve the required decrease, inflows of ground and surface water to water-reducing devices and into mine workings - according to the stages of field development;

groundwater inflows through anti-filtration curtains, curtain thickness, position of groundwater levels on both sides of the curtains;

the required number of wells for anti-filtration curtains and the cost of materials for them, the distribution of injected materials in the rock mass, the required time to create stable anti-filtration curtains;

productivity, throughput, dimensions, number, placement and other parameters of devices for water reduction, water collection, drainage, anti-filtration curtains and implementation of anti-filtration measures;

the need for material and energy resources;

assessment of the quality of pumped water and possible changes in the quality of ground and surface water;

assessment of damage to river flow, agriculture, forestry, and water supply settlements and enterprises from the operation of water reduction devices;

risk assessment due to the possibility of activation of exogenous processes (karst, suffusion, internal erosion, etc.) as a result of technogenic impacts of a hydrogeological nature.

In addition, during design it is necessary to determine the expected deformations of the earth's surface in the zone of influence of water-reducing systems.

As a rule, calculated values ​​should be justified by experimental data.

4.8 The design documentation should provide for the installation of observation wells and posts, geodetic benchmarks, marks and surveying points, the installation of control and measuring equipment and the period for putting them into operation for conducting hydrogeological, hydrological, surveying and geodetic observations, as well as observations of the operation of protection system devices during their construction and operation.

Programs for monitoring and industrial environmental control (composition and modes of necessary observations) must be established in the project documentation. Observations should be made of the levels, temperature, chemical and gas composition of groundwater, air temperature, amount of precipitation, water levels in reservoirs, flow rate, temperature, chemical and gas composition of pumped water, deformation of rocks and the earth’s surface, precipitation and deformation of structures etc.

Design of open pit protection

4.9 The design documentation for the protection of open-pit mines should provide for:

external structures and measures to regulate surface runoff in the area adjacent to the quarry (mine);

structures and measures to reduce or prevent filtration losses from water-filled reservoirs (settlements, industrial wastewater storage tanks, tailings ponds, etc.) adjacent to the quarry (mine);

in-quarry devices and measures designed for the influx of groundwater entering the quarry and for the collection and removal of surface water collected in it: drains, catch basins, drainage installations or devices for discharging water from catch basins into underground workings and, if necessary, depending on local conditions - in-quarry borehole and wellpoint water reduction installations, local grouting of rocks, drainage, loading of slopes;

external drainage devices for discharging quarry water.

4.10 If necessary, from the conditions of ensuring the stability of the sides of the workings or according to production conditions, reducing the influx of groundwater into the quarry (cut trench, exit trench, etc.) in the design documentation, in addition to the devices and measures provided for in 4.9, contour ring or partial ring and linear external water-reducing systems or impervious curtains should be provided.

Ring water-reducing systems should be provided when aquifers spread throughout the entire protected area and beyond.

Non-full-ring water-reducing systems should be designed when aquifers do not spread from all sides of the protected area.

Linear water-reducing systems should be designed to intercept one-way underground flow from the side of a reservoir (watercourse) or along a layer that has a pronounced slope towards the protected area, as well as to protect extended workings and in cases where local conditions make their use advisable.

4.11 Ring, partial ring and linear impervious curtains should be designed in the same cases as the corresponding water-reducing systems (see 4.10), taking into account restrictions for the use of certain types of curtains due to natural conditions (according to the instructions in Section 7) and local production capabilities.

4.12 Water-reducing and anti-filtration devices of quarries (cuts) may be provided in the form of separately located elements of the protection system, placed for their greatest efficiency and taking into account the topography of the underlying aquifer, the occurrence of rocks with high water permeability, the direction of underground flow, etc.

4.13 Reducing the piezometric level of pressure water to maintain the stability of rocks and prevent water breakthrough into workings can be provided using devices specially designed for this purpose (wells equipped with pumps, self-flowing wells, etc.).

4.14 When designing a quarry (cut) protection system carried out in several stages, it is necessary to provide for:

before the start of construction of a quarry (mine) - commissioning of external structures and devices to regulate surface runoff and drainage, commissioning of structures, devices and implementation of measures necessary to protect mine workings from groundwater for the period during which the structures can be prepared , devices and activities of the next stage;

When designing a protection system with external water-reducing or anti-filtration devices, it is necessary to provide for measures to ensure that the development of a quarry (cut) advances the development of a decrease in the groundwater level. When designing a mining protection system without external devices - the availability of funds to carry out the necessary measures and implement the necessary devices in the process of developing a quarry (mine);

during the construction of a quarry (mine) - sequential commissioning of additional structures and devices and carrying out the necessary measures provided for in the design documentation (see 4.10-4.13);

by the time the quarry (mine) is put into operation - the readiness of structures and devices that ensure the protection of mine workings until the full design productivity of the quarry (mine) is achieved, including the readiness of the designed system for regulating surface runoff, drainage, stationary drainage and drainage of mine water;

during the operation of the quarry - the sequential commissioning of structures and devices and the implementation of measures designed in the protection system and ensuring a constant advance in relation to mining operations in the development of lowering the level of groundwater or impervious devices for the period provided for in the design documentation.

Design of underground mine protection

4.15 The design documentation for the protection of underground workings, depending on local conditions within the mine field, should provide for the use of:

as underground drainage - the protected workings themselves with the installation of drainage grooves in them;

vertical, horizontal and inclined (upward and downward) self-flowing wells, drilled, caught (or driven) from the protected workings themselves, drainage workings from special niches and chambers;

through discharge wells, drilled from the surface and driven into the protected or drainage workings themselves;

wells equipped with pumps and constructed from the surface or from underground workings; wellpoint filters in underground mines; anti-filtration curtains (rock grouting);

appropriate structures and measures to regulate surface runoff, including water accumulating in troughs of displacement of the earth's surface.

In all cases, projects for the protection of underground workings must provide devices and installations for drainage and drainage of pumped water to places of discharge.

Note - The surface flow control system, if necessary, should cover the territory outside the mine field within the limits established by the project.

4.16 In cases of immediate threat of breakthroughs in underground workings of water and rocks, in particular when non-rock aquifers lie above the roof of the mineral deposit, it is allowed to provide in the design documentation for off-mine water-reducing systems and impervious curtains, arranged in accordance with the requirements of 4.10-4.13.

The permissible amount of water inflow into the development and treatment workings at mineral deposits should be taken based on the experience of constructing and operating mines under similar conditions.

4.17 When designing the protection of mine workings passing in an aquifer, from which significant inflows of water are expected, it is allowed, with proper justification, to provide for the creation of special drainage horizons within the mine field, placing drainage workings below the main haulage horizons.

4.18 When designing the protection of mine workings, it is necessary to take into account that their excavation in undrained rocks should be provided with advanced drilling and compliance with the requirements of 4.15, and, in necessary cases, with preliminary freezing of rocks or using the shield method.

4.19 When designing an underground mine protection system carried out in several stages, it is necessary to provide for:

before the start of shaft sinking - commissioning of structures and devices for regulating surface runoff enclosing mine shaft sites, drilling advanced control and exploration wells to the entire depth of the shaft, readiness of external shaft impervious curtains or water-reducing systems, if they are provided for in the design documentation, readiness for preliminary plugging rocks;

before the start of excavation of preparatory workings - commissioning of a drainage installation at the mine shaft (it is allowed to provide for the excavation of preparatory workings with the operation of a temporary pumping station, designed for the expected influx in the period until the readiness of the designed stationary pumping station), commissioning of sump and pumping stations and off-mine water reduction systems, if they are provided for in the design documentation;

during the period of excavation of preparatory workings - sequential commissioning of additional structures and devices and carrying out the necessary measures provided for in the design documentation (see 4.16-4.18);

by the time of the start of cleanup work - ensuring a decrease in the level of groundwater, the readiness of structures and devices that ensure the protection of underground workings until the full design productivity of the enterprise is achieved, including the readiness of stationary underground pumping stations and systems for regulating surface runoff and drainage;

during the operation of the enterprise - further sequential commissioning of the designed structures and devices and implementation of measures that ensure constant advanced (in relation to mining operations) development of lowering the level of groundwater or corresponding impervious devices for the period determined by the design documentation.

5 Dewatering

General instructions

5.1 Water reduction should be designed using open and vacuum dewatering wells, wellpoints, reservoir, tubular and trench drainages, and underground drainage workings.

5.2 The required amount of pressure reduction in aquifers should be determined from the condition of maintaining the stability of the rocks surrounding the workings and preventing the breakthrough of groundwater into them.

5.3 When designing a water reduction system using an external water reduction system that protects an open mine, the groundwater level should be lowered, if possible, below its bottom by an amount determined by the calculated increase in the water level during an emergency shutdown of the water reduction system.

If it is impossible to lower the groundwater level below the bottom of an open pit, in particular when it crosses aquifer layers, it is necessary to proceed from the practically achievable depth of water decline in each aquifer and provide additional in-pit devices and measures in accordance with 4.9.

5.4 When designing water reduction using off-mine water reduction devices that protect underground mine workings in aquifers that are not separated by an aquitard from overlying aquifers, the reduced groundwater level must be below the base of the protected underground workings to a depth that meets the requirements of 5.3.

If there is an aquitard (rocks with a filtration coefficient of less than 0.001 m/day), separating the rock mass in which underground workings are designed from the overlying aquifer, a decrease in the groundwater level in this horizon, as a rule, should be prescribed taking into account compliance with the condition

where y is the residual pressure measured from the roof of the separating layer of waterproof rocks, m;

Thickness of the separating layer of waterproof rocks not disturbed during development, m.

5.5 The required time to achieve the required reduction in groundwater levels, the spread of depression and the development of the water reduction system should be determined in accordance with the mining plan and hydrogeological justification.

5.6 The schematization of natural conditions for calculating water drawdown should reflect the actual hydrogeological conditions, the geological structure of the strata and the characteristics of its constituent layers.

5.7 When calculating water reduction, the influx of groundwater to the water reduction system should be determined based on the basic linear law of laminar filtration, expressed in general view formula

where v is the filtration rate, m/day;

k - filtration coefficient, m/day;

I - pressure gradient.

Basic calculation formulas and tables for determining inflows to the water-reducing system are given in Appendix A.

If it is necessary to use water reduction in aquifers composed of rocks characterized by high filtration properties (coarse clastic, highly fractured and karst), the calculation of water reduction can be based on experimental data and clarified during the phased implementation of the protection system, based on the results of observations of groundwater levels in observation wells .

5.8 For conditions of increased complexity (non-uniform filtration flow, complex contours of supply and water reduction circuits, etc.), the calculation of water reduction systems should be carried out using numerical modeling, as well as engineering calculation programs and software packages or other methods.

5.9 The designs of water-reducing and observation wells and drainages should be adopted in accordance with the instructions in Appendix B.

Open dewatering wells

5.10 Open (connected to the atmosphere) water-reducing wells should be provided, as a rule, to reduce the level (or pressure) of groundwater in non-rock formations with a filtration coefficient of at least 2 m/day and in all other cases when their effectiveness is confirmed by experimental data.

5.11 When designing water-reducing systems, open water-reducing wells should be provided in the form of:

equipped with pumps;

through discharge wells equipped with filters through which groundwater entering the well from all the aquifers it cuts through is discharged into underground workings;

self-flowing with water pouring out through the mouth;

water absorbers, with the help of which groundwater from the overlying horizon is discharged into the underlying one.

5.12 Wells equipped with pumps should be provided for contour and linear water-reducing systems, and also designed in the form of separately located water-reducing devices for open-pit and underground mining of mineral deposits and in the form of water-reducing devices distributed over the area of ​​the mine field for underground mining of mineral resources.

5.13 Through discharge wells (through filters) should be provided for contour and linear water-reducing systems, as well as in the form of separately located or distributed over the area of ​​the mine field water-reducing devices during underground mining of mineral resources and during open-pit mining of mineral deposits, when technically possible and economically justified installation of underground drainage workings.

5.14 Vertical self-flowing wells to relieve excess pressure in underlying aquifers should be provided to protect against disruption of rock stability and prevent dangerous breakthroughs of pressure water into open or underground mine workings.

Drilling of self-flowing wells should be done from the surface of the earth, from berms on the sides of quarries (cuts), from the bottom of open or underground workings. The well must be buried in the most permeable zone of the aquifer containing pressurized water.

5.15 Horizontal or downward self-flowing wells, installed from berms on slopes, should be provided in the base of aquifers near their contact with impermeable layers or in places of concentrated filtration to prevent suffusion of rock through the slopes of open workings.

Horizontal or downward wells on the slopes of open workings may be provided as an auxiliary means for an external water-reducing system from wells equipped with pumps, or from through discharge wells (or with an impervious curtain), as well as as one of the main means for maintaining permanent sides of the workings lower groundwater levels achieved through other means (for example, open drainage).

5.16 The design documentation should provide for the use of self-flowing wells (rising, descending or horizontal - depending on hydrogeological conditions) in underground workings to enhance the drainage capacity of the working itself, as well as to reduce water in aquiferous rocks and layers separated from the working by water-resistant layers and layers.

5.17 In case of horizontal occurrence of aquifers, it is allowed to provide for the use of radial drainages for water reduction, consisting of shaft wells with pumps installed in them, and radial (radial) wells drilled from wells, usually horizontal (and, if necessary, inclined) self-flowing wells.

5.18 Water absorption wells should be provided when there is a water-permeable layer that has a high absorption capacity below the drainable layer located on the aquiclude. The pressure in the absorption layer should be lower than in the drained layer. The greater the difference in pressure, the more efficient the operation of water absorption wells.

Vacuum water reduction

5.19 Vacuum dewatering should be designed using light wellpoint vacuum dewatering units, ejector wellpoints, vacuum-concentric wells and vacuum wells with submersible pumps, as well as dewatering wells drilled from underground workings with the connection to them of units and collectors of vacuum dewatering units or other vacuum systems.

5.20 Inventory wellpoint filters should be used as part of water-reducing systems in open and underground workings:

light ones that do not have individual water lifts and are connected to the central pumping station by a common (for a group of wellpoints) suction manifold;

ejector, equipped with individual ejector water lifts and connected to the central pumping station by a common (for a group of wellpoints) pressure and drainage conduits;

vacuum-concentric, equipped with individual ejector water lifts and connected to the central pumping station by pressure and drainage water conduits.

5.21 The inventory wellpoint filter (wellpoint column) consists of a tip, a filter unit (filter units) and blind units of the above-filter pipes.

5.22 It should be possible to immerse light and ejector wellpoints to a depth of 12-15 m mechanically by driving or crushing using, as a rule, hydraulic erosion (hydraulic immersion method). If it is necessary to cross difficult-to-erode rocks with light and ejector wellpoints and in all cases of immersion into the drained layer of vacuum-concentric water intakes, drilling of wells should be provided for them.

5.23 Light wellpoint filter installations of gravity water reduction (LIU type) should be used mainly as part of in-pit protection systems (and, if necessary, in underground workings) with the required depth of groundwater level reduction to 4-5 m, counting from the level of the axis of the pumping unit (or at greater depth - using tiered systems) in rocks with filtration coefficients of 5-50 m/day - without sprinkling around the wellpoints, and with a filtration coefficient of 2-5 m/day - with sand and gravel dressing around the wellpoints to the entire height of the aquifer.

5.24 Sand with particles with a particle size of 0.5-2 mm or a sand-gravel (crushed stone) mixture with a particle size of 0.5-5 mm should be used as a material for covering wellpoints. Wellpoint filters must be installed in accordance with the requirements of Appendix B and SP 45.13330.

5.25 Light wellpoint units for vacuum water reduction (UVV, UVZM types, etc.), ejector wellpoint units (EI type) and units with vacuum-concentric water receivers (EVVU type) should be used, as a rule, for water reduction in rocks with a filtration coefficient of less than 2 m/day

5.26 Installations with ejector wellpoint filters may be provided for vacuum dewatering when the groundwater level drops to 12 m (with proper justification - up to 20 m), counting from the level of the axis of the pumping unit.

5.27 Installations of vacuum-concentric wells with ejector water lifts should be designed for drainage of layered strata represented by aquifers, separated loamy or clayey layers, within water depression depths of up to 20 m.

5.28 When designing the drainage of sandy-clayey rocks with a filtration coefficient of up to 2 m/day, the depth of immersion of wellpoints of air-blast installations should be no more than 7.5 m, and in rocks with a filtration coefficient of more than 2 m/day - 8.5-9 m, counting from the level of the axis of the pumping unit.

5.29 The placement of wellpoints should be designed in the form of loop or linear systems.

5.30 Vacuum dewatering installations may be provided as an auxiliary means when opening open mine workings and for taking water and air from wells drilled from underground mine workings.

5.31 When designing wellpoint systems for operation in conditions of negative air temperatures, insulation of pipelines and pumping stations should be provided taking into account the requirements.

5.32 When designing power supply for wellpoint installations, it is necessary to comply with the same requirements as for well pumps (see Appendix B).

5.33 Vacuum water reduction using vacuum wells with submersible pumps should be provided to reduce the groundwater level in rocks with filtration coefficients of 0.1-2 m/day and to completely intercept the influx of groundwater to the mine workings (lowering the groundwater level to aquiclude).

5.34 When designing a vacuum dewatering system, one should take into account the increased danger of carrying out small particles from drained rocks into wells and wellpoints and provide in all cases with sand and gravel filling of filters that meets the requirements of Appendix B, using, if necessary, basket and casing filters.

5.35 Well filters in open mine workings, to prevent excessive air intake, should be placed at a distance from the slopes of at least the thickness of the layer to be drained. With appropriate justification, this distance can be reduced.

The wellhead near the upper sections of the above-filter pipes should be equipped with a clay lock made of compacted low-permeability soil (loam, clay) or a monolithic concrete collar.

5.36 When designing vacuum systems to create the required reduction in the level of groundwater in the case of an aquitard located close to the bottom of a mine opening, and to completely intercept the influx of groundwater to workings that are perfect in terms of the degree of opening of the aquifer, filters should be placed directly at the roof of the aquifer.

If it is necessary to reduce pressure in aquifers of a layered strata or to completely drain them in the area adjacent to the workings, well filters should be placed within all layers to be drained.

5.37 Systems of vacuum wells equipped with pumps in a homogeneous aquifer should be provided with the required reduction in the groundwater level to 20 m. With a layered composition of the drained strata (the presence in it of a number of layers of water-bearing rocks separated by impermeable layers), as well as in closed (limited impermeable contours) layers of water-bearing rocks, it is allowed to use vacuum wells with a depth of up to 100 m or more.

5.38 The minimum water level in the vacuum well must ensure flooding of the pump sufficient for its operation without interruption of pumping, in accordance with the requirements of the manufacturer and taking into account the vacuum above the dynamic water level in the well. The pressure in the vacuum well, accepted in the design documentation, must correspond to the maximum unreduced groundwater level.

5.39 Calculation of vacuum water reduction must be made taking into account unsteady filtration of water at constant pressure. The air flow to the well (wellpoint filters) can be determined using steady-state filtration formulas.

5.40 The design documentation for systems for protecting mine workings from groundwater should provide for the use of reservoir, tubular, trench drainages and underground drainage workings (gallery drainages).

5.41 Seam drainage should be provided in open excavations to prevent suffusion of soil from the bottom and sides of the excavation and destruction of rocks, when it is impossible or economically infeasible to completely prevent the seepage of groundwater through slopes. Reservoir drainages also perform the task of lowering the groundwater level in the area adjacent to the open working.

Formative drains can be used to drain internal dumps.

The need for drainage of dumps and its design solution are established together with the solution of dumping technology and the organization of surface runoff, taking into account the nature of the rocks at the base of the dumps and other local conditions.

5.42 Tubular drainage should be provided when a line of seepage of groundwater extends along the front of the side of the quarry (cut) onto slopes in unstable rocks lying above the aquitard.

Tubular drainage must be cut into the aquifer layers in order to completely intercept the flow of groundwater above the aquifer in the design section (in the drainage plane).

5.43 Trench drainages (open and closed drainage trenches, ditches, trays) are allowed to be used as external water-reducing devices (mainly linear) in the upper aquifers, in the form of advanced trenches - when opening a deposit in an open way without external water-reducing devices and in the form of ditches in berms (platforms) of the sides of a quarry (cut).

Ditches on berms inside a quarry (cut) should simultaneously be used to collect and drain surface water. The cross-section of the ditches must meet the requirements of Section 8.

It is advisable to drain water collecting in trenches and ditches by gravity outside the quarry field to the mine water discharge site or to quarry catch basins via the intra-quarry drainage network.

5.44 Underground drainage workings (gallery drainage) of through and semi-through sections should be used for direct drainage of the surrounding rock mass or for water reduction in overlying and underlying aquifers using through discharge wells (through filters) and water-reducing wells drilled from the workings themselves, operating as self-dispensing (if necessary, equipped with individual pumps) or as vacuum.

During underground mining of mineral resources, it is allowed to provide for the use of main mine workings as drainage, in which grooves or trays for water drainage must be designed for this purpose.

In underground drainage workings and in the main workings used as drainage, walkways should be provided for connecting with through discharge wells (through filters) and niches for drilling water-reducing wells, if their use is planned.

Underground drainage workings can be designed to protect both a mine and a quarry field, using them in external water-reducing systems (circular, partial ring and linear) or located in the form of systematic drainage below open workings or in the system of mining workings of a mine field.

In underground drainage workings in which operational work will be carried out (supervision of through discharge wells, drilling of riser wells, etc.), an alarm system should be provided to notify the people in them in the event of an accident in the drainage system and, if necessary, telephone communication with the control room point.

When designing drainage excavations, it is necessary to comply with the requirements of SP 91.13330.

Observation wells

5.45 When designing the placement of observation wells for the water reduction process, it is necessary to take into account that observations of the regime and characteristics of groundwater must cover the entire territory where the influence of water reduction is possible throughout the entire estimated life of the field.

5.46 If there are several drainable aquifers in the observation area, observation wells, separate piezometers or level sensors must be provided in all horizons. When installing a filter, piezometer or level sensor at the level of each horizon, it is necessary to ensure that the horizons are separated from each other. It must be possible to take groundwater samples for chemical analysis from different height levels of aquifers.

5.47 Observation wells should be provided at all calculated points where the drop in groundwater level was taken as an initial value or determined by calculation.

Observation wells should be placed in areas with characteristic hydrogeological conditions, taking into account the location of sources of pollution (tailings, hydraulic dumps, etc.), recharge and discharge (surface watercourses, reservoirs, etc.) of groundwater.

Under relatively simple hydrogeological conditions, it is allowed to place observation wells along the sections (beams).

Observation well beams should be assigned:

for flat-lying aquifers - in the direction of the flow and in the cross of the flow (natural), in the direction of the most likely areas of recharge and neighboring water reduction systems (water supply, drainage);

for steeply dipping aquifers - along the strike and across the strike of the horizons, in the direction of probable sources of supply and neighboring water reduction systems (water supply, drainage);

for extended (linear) systems - perpendicular to the axis of the system.

The design documentation of the contour water-reducing system should provide for at least two beams of observation wells and take at least two wells on the beam, one of which is on the contour, and the second is outside it at the selected design point.

If the zone of influence of the contour water-reducing system is large, the number of wells on the beam in the aquifer of interest should be taken from three to five, placing the first one on the contour.

6 Drainage from mine workings

General instructions

6.1 The design documentation of protection systems should provide for the installation of pumping stations for pumping water directly from mine workings when it is impossible or impractical to drain the water entering them by gravity.

6.2 When designing, it is necessary to distinguish between normal and maximum inflows to pumping stations.

The normal inflow to pumping stations consists of the influx of groundwater, determined on the basis of hydrogeological calculations, and water systematically consumed in mine workings for technological and domestic needs (dust suppression, hydromechanization, etc.).

The maximum inflow to pumping stations is determined by summing the values ​​of the normal inflow and the influx of surface water, determined in accordance with the instructions in Section 8, formed due to atmospheric precipitation falling directly on the area of ​​the quarry or mine field.

6.3 Pumping stations with a total power of working and standby pumps exceeding 100 kW should, as a rule, be designed in a block with electrical substations.

6.4 The design documentation should provide for main, local and transfer pumping stations, and temporary ones for the period of their construction. In addition, it is necessary to provide mobile or portable pumping units for use in bottomhole and other places as necessary.

6.5 Pressure pipelines must be designed for the full capacity of the pumping station.

As a rule, at least two pressure pipelines should be provided within mine workings for pumping stations. One pressure pipeline may be provided for local pumping stations, as well as for the main quarry pumping station in case of possible flooding of the lower horizon.

If there is more than one pressure pipeline, normal inflow pumping must be ensured when one of them is disconnected.

6.6 The placement of shut-off valves on the pressure and suction pipelines must ensure the possibility of replacing or repairing any of the pumps, check valves, as well as the main shut-off valves, ensuring continuous pumping of normal inflow and operation of each pump to any pressure pipeline.

The water speed in the suction and pressure pipelines, as a rule, should not exceed 1.5 and 3 m/s, respectively.

6.7 When designing drainage structures, you should use technological schemes and equipment that makes it possible to mechanize installation work and cleaning of containers (water collectors, clarifiers, sumps, grooves, etc.).

Note - When cutting water-reducing wells into aquifers suitable for drinking water supply, as a rule, separate selection and disposal of drainage water should be provided (9.2).

Drainage from open workings

6.8 The design documentation must provide for the installation of a network of drains and discharge lines for the collection and organized drainage of groundwater and surface water entering the excavations to catch basins and sumps at pumping stations. Drains and discharge lines must be designed for maximum inflow and meet the requirements of Section 8.

6.9 Main pumping stations (stationary or floating) with water collectors should be located taking into account horizontal inflows of groundwater, the catchment area of ​​surface water and ensuring minimal drainage costs.

6.10 Local pumping stations (stationary, mobile, floating) with water collectors that pump water directly into external drainage devices or into the water collectors of the main pumping stations should be designed to serve individual sections of the quarry (mine).

6.11 Mobile or portable pumping units with sumps may be provided for pumping water from separate isolated sections of the mine.

The need for pumping stations in a quarry (mine) is established when choosing a general quarry drainage scheme and performing the corresponding technical and economic calculations.

6.12 The capacity of quarry catch basins, for which, if possible, it is necessary to use mined-out space, at the main and each local pumping stations should, as a rule, be equal to the volume of the design flow from the corresponding catchment area (see Section 8) minus the volume of water pumped out during filling drainage basin, if provided for in the design documentation.

If it is impossible to fulfill this requirement, the design documentation must provide for the necessary measures to allow temporary flooding of the lower working horizons, and water reservoirs with a capacity equal to at least 3-hour normal inflow.

The capacity of the sumps should be no less than the 5-minute maximum flow of one of the pumps.

Catchment basins must have settling tanks for water clarification and the possibility of their periodic cleaning.

6.13 Quarry drainage as the main means of protecting a quarry (cut) may be provided subject to compliance with requirement 6.10-6.12 in the following cases:

in rocky and semi-rocky formations, when the organization of collection and removal of groundwater entering the mine does not cause complications with the accepted methods and systems of field development;

in non-rock formations during the construction or deepening of a quarry (cut) when conducting mining operations with advanced trenches buried below the workings horizon, during underwater mining of rocks and in other cases when this does not cause complications for the accepted methods of mining.

6.14 To ensure the stability of the sides and bottom of excavations in non-rocky rocks during their development or drainage, and to exclude suffusion processes, the rate of decrease in the water level in the excavation should be no more than the values ​​​​given in Table 1.

For specific conditions, the rate of decrease in the water level in the excavation can be determined by numerical modeling or calculations using engineering calculation programs and software packages based on the condition that the rate of decrease in the water level in the excavation must correspond to the rate of decrease in the groundwater level outside it.

Table 1

6.15 When mining rocks using hydromechanization, pumping out groundwater and surface water, in whole or in part, may be provided by dredgers pumping out the pulp.

In the face of a hydromechanical development, the design documentation may allow for increased filtration of groundwater through the slopes of the excavation, which contributes to the destruction of the rock being mined and does not pose a threat to the overall stability of the sides of the quarry (cut).

6.16 If the lower working horizons are flooded (see 6.12), as well as if it is impossible to ensure the permissible suction height of pumps when installed permanently, the main and local pumping stations should be designed as floating ones.

6.17 The number of working pumps at main and local pumping stations should be determined in accordance with the requirements. The pumps of the main (or district) pumping stations must have the same pressure. When pumping out maximum inflows, continuous operation of all working pumps must be provided.

The number of working pumps at mobile, portable and temporary pumping stations should be taken based on the continuous pumping of normal inflow.

6.18 With proper justification, it is allowed to provide for the discharge of clarified water into an underground drainage system or into water-absorbing layers, taking into account the requirements of Section 9.

Discharge must be carried out through wells, the number of which is determined by calculation, while reserve discharge wells must make up 25% of the total number, but not less than one well.

The discharge of quarry water into the underground drainage system must be regulated and consistent with the capacity of the underground pumping station.

6.19 When designing pumping stations in open-pit mines, it is necessary to comply with the requirements of SP 32.13330 regarding the number of backup pumps, the width of passages between the protruding parts of pumps, pipelines and engines, the laying of suction pipelines, the dimensions of the machine room and installation sites, and the dimensions of handling equipment.

Drainage from underground mines

6.20 The layout of stationary drainage installations must be taken depending on the simultaneously operating inflow horizons, the depth of their occurrence, the size of the mine (quarry) field, the magnitude of the inflows of underground, process and surface waters.

6.21 The main pumping stations should be located near the shafts with the lowest elevations of the near-shaft yards.

For long mine workings and when necessary due to drainage conditions, it is allowed to additionally provide local stationary pumping stations.

6.22 In underground pumping stations, the number of working pumps and their total number, taking into account reserve ones and those under repair, must be determined based on normal inflow and in accordance with the requirements and.

Pumping of the maximum inflow should be provided taking into account the regulation of the discharge of quarry water into the underground drainage system (see 6.18).

6.23 Main and district pumping stations should be designed of a non-buried type (pump housings are located above the water level in the reservoir) with check valves on suction pipelines with a diameter of up to 200 mm, with the installation of vacuum pumps or booster pumps and of a buried type (pump housings are located below the level water in the catchment) - with a diameter over 200 mm. In this case, buried pumping stations should be provided, as a rule, in slightly fractured rocks with a uniaxial compressive strength in a water-saturated state of more than 80 MPa and inflows of more than 1000.

6.24 When designing pumping stations and electrical substations in aquifers, it is necessary to provide for drainage or waterproofing and grouting of the surrounding rocks.

6.25 In the chambers of buried pumping stations, it is necessary to provide separate channels, covered with removable shields, for laying pipelines and cables, pits and pumps for pumping out dripping water, as well as water in case of accidents inside pumping stations.

6.26 The floor of the chamber of a non-buried pumping station should be at least 0.5 m above the level of the rail head in the near-shaft yard.

6.27 When the number of pumps is over 10, it is allowed to install two electric cranes for transporting and installing equipment, and the equipment should be delivered to the pumping room from two opposite sides of the chamber.

6.28 Water intake wells are allowed individually for each pump and in groups.

If the number of pumping units in a pumping station is more than three, the total number of wells must be at least two.

6.29 When determining the capacity of catchment basins, one should take into account the capacity of the drainage workings provided for in the project, temporary filling of which with water will not cause flooding of the main workings. The total capacity of the water tanks must meet the requirements regulatory documents specified in 6.22 and SP 91.13330.

6.30 In case of significant inflows of water (over 5 thousand), it is allowed to use special workings as the main reservoir reservoirs, which should be carried out parallel to the main mine workings at lower elevations. As a rule, the roof of the drainage excavation should be at the level of the soil of the main excavation. The slopes of the workings must be chosen in such a way that water can flow through the breaks into the main haulage workings only after all the catch basins have been flooded.

At the junction of the working-drainage basin with the collector of the pumping station, a blind sealed lintel with culverts and control valves should be constructed.

6.31 All exits from pumping stations to the mine yard should be provided with hermetically sealed doors designed for a pressure of 0.1 MPa (1).

6.32 For underground pumping stations with non-aggressive water, the design documentation should include the usual centrifugal pumps. In the presence of underground acidic water (pH< 5) следует предусматривать установку насосов, арматуры, трубопроводов и аппаратуры автоматического управления из кислотостойких материалов.

6.33 Each pump of temporary and permanent pumping stations must have a separate suction pipeline and must be equipped with appropriate measuring instruments (pressure gauge, vacuum gauge) to determine the pressure in the suction and discharge pipes.

6.34 Pressure pipelines should be located, as a rule, in a shaft equipped with a cage lift or having a ladder compartment.

It is prohibited to lay pressure pipelines in the shafts against the end sides of the cage.

If the number of pressure pipelines is more than four (with a diameter of more than 300 mm), they should be laid in special pipe and cable openings.

6.35 To dampen hydraulic shocks on pressure pipelines, it is necessary to provide for the installation of check valves or other protective devices.

Calculation of the strength of pipeline walls and metal structures of supports should be carried out (taking into account possible water hammer) for twice the hydrostatic head.

Pressure pipelines within the pump station and pipe walker - up to the shaft (or pipe riser) should be secured on special supports that can prevent displacement and collapse of pipes when a water hammer occurs.

6.36 When a pumping station is located at a depth of more than 200 m from the ground surface, it is necessary to provide temperature compensators on pressure pipelines. The upper compensator should be provided at a depth of more than 20 m from the surface.

6.37 Sump pumping stations must be equipped with two pumping units - a working one and a standby one.

6.38 When designing chambers and catch basins of temporary pumping stations, the same requirements should be observed as when designing the corresponding chambers of stationary drainage systems.

6.39 Temporary pumping stations for the construction of near-shaft yards and main haulage workings should be built near the shafts in workings running in the direction of the main underground watercourses.

Temporary pumping stations should be designed, as a rule, of a non-buried type.

6.40 When sinking a mine shaft, it is necessary to provide for drainage from it with a suspended pump, and, if necessary (with a shaft depth of more than 250 m), the installation of pumping stations.

6.41 The influx of groundwater to a shaft that is not secured with permanent support, in the absence of an external water-reducing system and anti-filtration devices, should be determined from the condition of a decrease in the groundwater level at the excavation wall to the full thickness of each aquifer cut by the shaft.

6.42 The permissible influx of groundwater into the bottom of shafts should be taken for the adopted method of excavation in accordance with the requirements of SP 69.13330.

6.43 When designing an external water-reducing system or an impervious curtain, it should be taken into account that the residual inflow into the bottom of the shaft, as a rule, should not exceed 8 in accordance with the requirements of SP 91.13330.

6.44 The design documentation must provide for catchment devices for collecting groundwater entering through the walls of the shaft and discharging them to the sumps.

6.45 Pumping stations should be provided taking into account their use, both during the construction of shafts and during subsequent periods of construction, and, if necessary, the operation of the mining enterprise.

When determining the dimensions of the chambers of pumping stations in shafts with a depth of more than 600 m, one should take into account the placement of a supply of power and control cables that ensure the operation of the suspended pump.

The water reservoir of pumping stations should be separated from the chamber by a reinforced concrete jumper and divided into two compartments by a partition.

6.46 Transfer pumping stations must be provided in shafts regardless of the method of their excavation; their number, service life, distance between them should be determined based on the drainage scheme (permanent or temporary), shaft depth and pumping equipment adopted.

Automation, dispatching, alarm, communication

6.48 When designing automation, dispatching, signaling and communication of permanent and temporary pumping stations for drainage from surface and underground mine workings, it is necessary to comply with the requirements , , , taking into account the requirements and .

At pumping stations, it is necessary to provide for automatic switching on and off of pumping units depending on the water level in the reservoir or sump, and automatic switching on of a backup pumping unit when any of the working pumps fails.

6.49 When designing automation, one should, as a rule, use sets of equipment that are commercially produced by industry.

For automated pumping stations, it is also necessary to provide for starting, stopping and monitoring the operation of pumping units from control centers (DP), located, as a rule, on the surface, and to provide for the transmission of emergency signals to the DP.

Dispatch projects should be carried out taking into account the possible use of telemeasurements of the main parameters (flow, pressure) characterizing the operation of the drainage system as a whole.

For all drainage installations, regardless of their automation, local control posts should be provided for carrying out repair and adjustment work.

6.50 Power supply for signaling devices and communications should be provided from two independent energy sources.

Power supply, electrical equipment, lighting

6.51 The design of power supply, lighting, selection of electrical equipment for pumping stations for drainage from surface and underground mine workings should be carried out in accordance with the requirements of , , and taking into account and , as well as the long-term development of the mining enterprise for at least the next 10 years.

6.52 The power supply should be designed in accordance with the classification of power receivers according to the category of ensuring power reliability:

local pumping stations and mobile pumping units with an inflow of over 50 - category II; .

The substation at the main pumping station must be supplied with at least two feeders. When one of the supply feeders is disconnected, the remaining ones must ensure the operation of the pumps when pumping out the maximum inflow.

7 Anti-filtration curtains

General instructions

7.1 In systems for protecting mine workings from groundwater, anti-filtration curtains (PFZ) should be provided: trench, pile, thin slotted, curtains made by jet grouting of soils, injection, ice-forming, sheet piling, curtains arranged by open methods.

PFZs are divided by type, method of construction and material, with or without soil replacement.

PPFs constructed in an open way (for example, in embankments of embankments) should be designed in accordance with SP 39.13330.

It is possible to install combined curtains, both in type and in the method of construction and materials.

When designing and installing PFZ, you must comply with the requirements of this set of rules, SP 23.13330, SP 45.13330, SP 69.13330 and.

7.2 The choice of the type and parameters of the anti-filtration curtain should be made based on the engineering-geological and hydrogeological conditions in the area of ​​the object protected from groundwater, the results of filtration calculations (research) and, if necessary, calculations for force effects.

7.3 Curtains, as a rule, must completely cut through aquiferous rocks and be buried in aquiferous rocks to a depth determined by the nature of the contact zone, the state of aquiferous rocks and the effective pressure on the curtain, but not less than 1 m with a well-defined layer boundary.

The use of imperfect (not reaching the aquifer) curtains must be justified by filtration and technical and economic calculations.

7.4 When designing anti-filtration curtains, it is necessary to justify by calculations the filtration stability of the curtain, its safety (strength) throughout the entire design service life and the stability of the rock mass that absorbs the pressure on the curtain.

7.5 Groundwater inflows through the curtain, brought to the aquitard, can be determined using the formulas of Appendix A based on the pressure drop from the upstream and downstream sides of the impervious curtain, m, determined by the formula

where is the thickness of the anti-filtration curtain, m;

The permissible pressure gradient across the curtain, determined, as a rule, from experimental data.

In case of complex hydrogeological conditions of the construction site or complex outlines of workings, the parameters of the filtration flow should be determined by numerical modeling, calculations using engineering calculation programs and software packages, or experimentally.

Filtration calculations of curtains should be clarified based on data from pilot production work (see 4.6).

The design documentation should provide for the reception of groundwater filtered through the curtain using in-quarry (in-mine) water-reducing devices and drains.

7.6 To monitor the pressure drop across the curtain (groundwater levels), the design documentation should include the installation of piezometric wells on both sides of the curtain and a level monitoring program taking into account the development of the quarry (cut) in stages (see 4.14, 7.25). Based on the results of observations, if necessary, anti-filtration measures at the next stage are adjusted, including the intake of groundwater filtered through the curtain.

7.7 Trench, pile, thin slotted PFZ, curtains made by jet grouting of soils should be designed in the form of contour and linear schemes to protect, as a rule, open workings from the influx of groundwater.

The material for filling the above types of curtains should be selected by technical and economic comparison, taking into account the magnitude of groundwater pressure, the service life of the curtain and the characteristics of the soil mass containing it.

In any case, curtains of these types, designated in the design documentation, must be continuous along the front, as well as in depth.

To ensure the continuity of the curtain in depth, it is allowed to install it at a variable depth (usually in steps), repeating the contour of the waterproof layer into which it is buried.

Trench curtains

7.8 Trench sectional and continuous curtains, made using the “wall in soil” method under the protection of a thixotropic clay solution, should be designed in non-rocky rocks without coarse inclusions with a depth determined by the capabilities of the earth-moving mechanisms and equipment used. Hardening (concrete, clay-cement mortar) and non-hardening materials (clays, loams, clayized soil, clay-soil pastes) are used as trench filler.

7.9 The thickness of trench curtains should be taken, as a rule, within the range of 0.5-1.0 m when using special equipment and up to 2.0-2.5 m when using general-purpose earthmoving machines.

Pile curtains

7.10 Pile curtains made of secant piles (intersecting bored piles) should be installed in non-rocky rocks, including those containing coarse inclusions, to a depth of 40-50 meters or more.

Bored piles for curtains should be provided, as a rule, with a diameter of 0.5-1.0 m from hardening materials (concrete or clay-cement mortar). The distance between the centers of the secant piles of the curtain should be no more than 0.7-0.8 of the diameter of the piles.

The calculated thickness of the curtain of secant piles is taken based on the thickness at the junction of the piles.

7.11 It is allowed to construct a pile curtain from bored piles adjacent to one another (drilled tangential piles) or with clear gaps between them, while to seal the curtain (ensure the continuity of the curtain) between adjacent bored piles, local soil-cement piles (combined PFZ) should be made using the jet grouting method soils (Jet-grouting technology, see 7.17) or perform sealing by other methods.

To select the technology parameters for constructing local (single) soil-cement piles using the jet cementation method, it is necessary, as a rule, to organize experimental sites.

7.12 The design thickness of the combined pile curtain is taken according to the smallest thickness at the junction of bored and soil-cement piles.

When installing a single-row curtain of contacting bored piles or piles located with a gap, soil-cement piles must be placed between the bored piles on the pressure side of the curtain.

Thin slot curtains

7.13 Thin slot curtains (5-20 cm), arranged by filling hardening (clay-cement mortar) and non-hardening (clay-soil pastes) material into the gap formed using an inventory flat metal element, should be provided in sandy and clayey rocks without coarse inclusions to a depth of up to 20 m.

7.14 When designing, it is necessary to provide for the development of trenches and drilling of wells for trench and pile curtains, as a rule, under the protection of a clay solution that ensures the stability of the walls from collapse and meets the requirements of SP 45.13330.

7.15 For the preparation of clay solutions, as a rule, bentonite clays should be used, and in their absence - local ones, having a plasticity number of at least 0.2, with a content of particles larger than 0.05 mm - no more than 10% and smaller than 0.005 mm - not less than 30% by weight of a dry soil sample. The density of the thixotropic solution on bentonite clays is 1.03-1.15, on local clays 1.10-1.30. It is allowed to provide mixtures of bentonite and local clays.

To improve the properties of clay solutions, various chemical reagents can be used, a list of which is given in SP 45.13330.

The suitability of local clays must be confirmed by laboratory tests of clay solutions.

Water for clay solutions should not cause their coagulation and should satisfy technical requirements concrete preparation.

7.16 The design documentation should provide for trench, pile and thin slot curtains materials that meet the following requirements:

concrete - mobility 16-20 cm (according to the draft of a standard cone); compressive strength class not lower than B15; water permeability grade not lower than W2; frost resistance grade not lower than F50;

clay-cement mortar - density 1.5-1.8; the compressive strength of the hardened mortar is not lower than 1.5 MPa (15); stone yield upon hardening is at least 98%; stability no more than 0.5; spread indicator - within the limits that allow it to be pumped from the mortar unit to the place of installation;

clay - predominantly lumpy structure (clump size from 10 cm to 1/3 of the trench width); consistency from hard to hard-plastic;

clayized soil (soil developed during trenching and enriched with clay solution) - content (by weight) of clay particles with their uniform distribution throughout the entire volume of the mixture - at least 10-15%; consistency that ensures high-quality placement in the trench;

clay-soil paste prepared in mixing plants from local lump clays or loams must satisfy the conditions for laying them in the body of the curtain and the design requirements for the water permeability of the curtain.

The filtration coefficient of hardening and plastic fillers of curtains should not exceed 0.005 m/day. In the absence of special experimental data, pressure gradients on the curtain can be taken according to Table 2.

Table 2

Curtains made by jet grouting of soils

7.17 Thin soil-cement curtains (10-30 cm), carried out using the method of laminar jet cementation of soils (Jet-grouting technology), should be installed in non-rocky soils, including those containing coarse inclusions, to a depth, as a rule, of up to 20 m or more with appropriate justification.

The installation of the curtain is carried out by stops: drilling a well with flushing with water or clay slurry (forward stroke of the drill string) and subsequent lifting of the drill string (reverse stroke) with the supply of cement slurry into the well through a monitor nozzle under pressure up to 70 MPa. The drill string is lifted without rotation (laminar cementation). The lifting speed of the drill string is usually 5-30 cm/min.

Stops completed with cementation (anti-filtration panels) are arranged sequentially or alternately. In the first case, the uncured soil-cement composite of the previous and subsequent panels form a seamless anti-filtration curtain, in the second case, the manufactured panel is adjacent to the previous anti-filtration panel that has gained strength.

The installation of impervious panels using the jet grouting method can be carried out with complete or partial replacement of the soil with cement mortar.

The pitch of the wells in the direct path of the drill string corresponds to the width of the impervious panel and is determined by the design documentation depending on the hydrogeological conditions, the required water tightness and, if necessary, the strength of the soil-cement composite, the adopted scheme for installing the curtain (sequentially or alternating), the method of excavation (Jet-1, Jet-2, Jet-3, etc.), accepted pressure and composition of the cement mortar, nozzle diameter, monitor lifting speed and other parameters.

To select the technology parameters for constructing a soil-cement slotted curtain using the jet cementation method, it is necessary, as a rule, to organize experimental sites. In similar hydrogeological conditions, it is permissible to accept the initial parameters for analogous objects.

Quality control of the soil-cement curtain should be carried out using non-destructive geophysical methods (seismoacoustic, electrical, georadar, etc.) in combination with opening test pits and drilling samples to determine the strength characteristics and water resistance of the soil-cement composite.

7.18 Soil-cement curtains made of intersecting soil-cement piles, performed by jet cementation of soils, should be installed in non-rocky soils, including those containing coarse inclusions, to a depth of 50 m or more and can be designed single-row or multi-row.

In multi-row curtains, the piles must be placed in a checkerboard pattern with the axes of the piles of the next row shifted relative to the previous one by an amount, as a rule, equal to half of the pile spacing accepted in the design documentation.

The thickness of the soil-cement curtain accepted in the design documentation is determined by filtration calculations and the requirements of 7.23.

7.19 The distance between the centers of the soil-cement piles of the curtain should be no more than 0.7-0.75 of the diameter of the piles in a single-row arrangement and no more than 0.85 of the diameter of the piles in a multi-row arrangement. The design documentation must provide for such a grid arrangement of soil-cement piles to ensure the continuity of the soil-cement stone of the curtain in plan.

7.20 The technology for constructing a PFZ from intersecting soil-cement piles, performed using jet technology (the technology for producing a soil-cement composite is described in 7.17), differs from laminar cementation in that the lifting of the monitor with the drill string is carried out simultaneously with its rotation at a speed of usually 10-30 rpm. Depending on the type of soil and technological parameters of jet cementation (see 7.17), the diameter of a soil-cement pile can reach 2 m or more. To increase the strength characteristics of soil-cement piles, their reinforcement is allowed.

The diameter, pitch of soil-cement piles, technological parameters of their installation are determined by design documentation and adjusted based on the results of experimental work.

7.21 Using the method of jet cementation of soils, it is permissible to install horizontal anti-seepage curtains to avoid the influx of groundwater into open workings through their bottom, while along the perimeter of the working it is necessary to provide contour water protection measures: water lowering, anti-filtration vertical curtains, etc. The use of this method must be economically justified.

7.22 With appropriate justification, it is allowed to provide a synthetic film laid from separate strips on the downstream side of the trench as an anti-filtration material for curtains.

The design of a curtain using film should include a soil filler that does not contain inclusions with sharp corners, and its installation with measures taken to prevent damage to the film.

7.23 Rigid curtains made of hardening materials must be designed for forces caused by hydrostatic pressure as a slab on an elastic foundation with a bed coefficient varying with depth.

7.24 The design documentation must indicate the order of construction of wells, grips, stopes, provide for quality control of materials, prepared solutions, mixtures, pastes, control of the work performed, the correctness of the geometric dimensions of the trench (slit) being developed, its verticality, as well as the continuity of the curtain and its interface with aquitard using a set of non-destructive testing methods (geophysical) and other methods (drilling samples) in accordance with this set of rules and SP 45.13330.

7.25 The anti-filtration properties of the curtain are determined based on observational data from piezometric wells at the top (pressure) and bottom faces of the curtain (7.6) and a study of the water permeability of samples drilled from the body of the curtain.

Injection curtains

7.26 To consolidate rocks and make them waterproof, it is necessary to provide for the installation of injection curtains and local grouting of rocks in individual sections of workings using cementation, clayization, resinization and silicization.

7.27 Injection curtains should be provided to protect vertical, inclined and horizontal underground workings from groundwater using rock grouting performed in the soil mass impregnation mode.

With proper justification, it is allowed to provide injection curtains (linear and contour) to protect open-pit mines from groundwater.

Depending on the geological and hydrogeological conditions of the occurrence of aquifers, it is possible to design injection curtains in combination with other types of curtains (trench, pile, etc.).

7.28 Cementation (injection of cement, clay-cement and clay-cement-sand mortars on cements for general construction purposes), as a rule, should be used to install curtains in rocky and semi-rocky fractured rocks with crack openings of more than 0.1 mm, specific water absorption of more than 0.01, free from filling or filled with easily washable secondary materials, with the actual speed of movement of groundwater through cracks no more than 2400 m/day. At higher speeds, the use of cementation should be justified experimentally. When designing and constructing a PFZ using the cementation method in rocks, it is necessary to comply with the requirements of SP 23.13330 and.

It is allowed to provide for the use of cementation using cements for general construction purposes in coarse-grained, gravel-pebble and sandy aquifers with a filtration coefficient of over 80 m/day. The well pattern (well spacing and number of rows), the method of cementation in the impregnation mode (descending, ascending, simultaneous), the amount of solution absorption at a given injection pressure is assigned by the design documentation, taking into account the requirements of 7.27, 7.37.

Cementation of sandy soils with a filtration coefficient from 1 to 80 m/day can be carried out using especially finely dispersed (OVTD) cements (mineral binders of the Microdur type of various brands) in the impregnation mode through injectors or wells. The radius of the soil-cement column after fastening is usually from 0.3 to 0.8 m.

Cementation of sands with a filtration coefficient from 0.1 to 80 m/day of any degree of humidity should be done using vibration cementation technology (immersing the injector into the ground using a high-frequency vibratory driver while simultaneously pumping cement mortar through it using cement for general construction purposes). The radius of the soil-cement column formed during vibration cementation is, as a rule, 0.15-0.4 m.

In the design documentation for cementation using OVTD and vibration cementation with single-row and multi-row arrangement of injectors (wells), the distance between their centers should be assigned with a reduction factor of 0.6 (massive leveling coefficient) from the accepted diameter of distribution of the suspension (solution) when consolidating rocks. When a multi-row arrangement of injectors is used, it is necessary to provide such a grid for their arrangement to ensure the continuity of the soil-cement composite of the curtain both in plan and in depth. The fixation radius depends on the composition of the suspension, the design of the injector, the granulometric composition of the sand being fixed and the injection pressure.

To select the composition of the injected suspension, injection pressure, clarify the dimensions of the resulting soil-cement column (assessing the permeability of rocks), determine the strength and water resistance of the soil-cement composite and other parameters, it is necessary, as a rule, to organize experimental sites.

7.29 When designing rock cementation, the choice of method (descending, ascending, simultaneous), composition and consistency of the cement solution (suspension), injection volume and pressure, and the magnitude of “failure” should be made depending on the purpose of the injection curtain, condition and engineering-geological properties fixed rocks, their fracturing and karst content, the actual rate of filtration of groundwater, filtration coefficient, as well as the chemical composition of groundwater.

7.30 For the preparation of cement mortars, Portland cement grade 400 and higher should be used. It is allowed to use sulfate-resistant cement, slag Portland cement and Portland cement cement. In the presence of aggressive waters, cements that are resistant to groundwater should be used.

Particularly finely dispersed (OVTD) mineral binders of the Microdur type of various brands or their analogues should be used to perform specific cementation work specified in 7.28.

7.31 Claying (injection of clay silicate solutions) should be provided in cases where cementation is uneconomical or unreliable due to the presence of aggressive waters that can corrode cement.

7.32 Resinization (injection of aqueous solutions of synthetic resins with a hardener through injectors or wells) should be provided for the installation of curtains in sandy rocks with filtration coefficients of 0.2-50 m/day.

7.33 Silication (one- and two-solution silicization) should be provided for the installation of curtains in sandy rocks. At the same time, in sands with filtration coefficients of 2-80 m/day, two-solution silicification should be provided: alternately injecting solutions based on sodium silicate and a hardener (calcium chloride, orthophosphoric acid, etc.) into the pores of rocks. In silty and fine sands with a filtration coefficient of 0.5-2.0 m/day, one-solution silicification should be provided - the injection of one solution of sodium silicate with the addition of phosphoric or hydrofluorosilicic acid. The radius of a mass (column) fixed by resinization or silicatization in sandy rocks is, as a rule, from 0.3 to 1 m.

7.34 It is allowed to provide for the combined use of cementation, clayization, resinization and silicization.

7.35 In the absence of special experimental data, the critical pressure gradient in the injection curtain can be taken in accordance with the instructions of SP 23.13330, depending on the type of non-rocky soil enclosing the curtain, and for rock and semi-rocky rocks fixed by cementation - depending on the value of specific water absorption within the curtain, designated by the design documentation.

7.36 The choice of the distance between the wells (well spacing and number of rows) of the injection curtain should be made based on the condition of ensuring its continuity and the filtration coefficient of the curtain, designed in non-rocky rocks, established by the design documentation, and determined by testing samples of fixed soil during experimental work (field or laboratory) . When installing an injection curtain in rocks, the filtration coefficient is determined according to SP 23.13330 depending on permissible value specific water absorption assigned by the design documentation. The thickness of the anti-filtration curtain must ensure that the critical pressure gradient, which determines the filtration strength of the curtain itself, is not exceeded.

The optimal distance between wells, as a rule, should be determined on the basis of experimental work. In the absence of experimental data, the distance between wells can be determined based on the radius of distribution of the injected solution, calculated by the formula

where is the flow rate of the solution injected into the well;

t is the duration of injection of the solution into the well, h;

Thickness of the layer of fixed soil, m;

The coefficient of uneven propagation of cracks and pores in rock;

e - rock porosity coefficient.

The radius of spread of the injected solution, obtained according to formula (4), must be clarified during pilot production work.

The pitch of the injectors in a row is assigned depending on the injection radius (4) and, as a rule, should be taken equal to , and the distance between the rows .

7.37 When designing an injection curtain, it is necessary to establish the method of injection of solution (descending, ascending, simultaneous), the sequence of driving (pressing) injectors or drilling wells, the size of the stope (zone) when injecting the solution, the sequence of injection in a row (in rows) using the sequential approach method. Wells of the first stage should be located at a distance that excludes their hydraulic connection along the pores and cracks of the soil during the process of injection of the solution (knocking out the solution into adjacent injectors or wells) and, as a rule, is taken to be no less than twice the distance between the wells. In rocks with heterogeneous permeability, the layer with greater permeability should be consolidated first. The sequence of injection work during the chemical consolidation of waterlogged sandy soils should ensure guaranteed displacement of groundwater from the volume of soil being consolidated by injected reagents. Entrapment of groundwater in the fixed massif is not allowed.

When installing a curtain in karst rocky soils, preliminary cementation should be carried out to localize the mass being fixed (creating a protective barrier) against the solution leaving the contour of the massif. The solution should be injected through each well until it fails. The anti-filtration properties of the curtain are checked by hydraulic testing, geophysical methods and the requirements of 7.6.

Injection of reagents into rocks during silicatization and resinization, as well as during cementation of coarse soils and gravelly sands, should be carried out under a load, which is used as rocks overlying the injection area or specially laid concrete slabs.

When installing injection curtains, one should control the inclination of the injectors (wells), the dimensions of the fixed rock mass, the continuity, uniformity of the curtain, anti-filtration properties, and, if necessary, the strength of the fixed soil (composite) of the curtain.

7.38 The installation of injection curtains should be provided from the surface or from the mine workings.

7.39 The direction (angle of inclination) of wells should be set taking into account the intersection of the largest number of predominant water-conducting cracks and bedding contacts.

7.40 The diameters of boreholes for the selected drilling method should be assigned in accordance with their depth, composition and structure of the rocks being passed, as well as taking into account the passage of the required flow rates of water and injected solutions.

Well diameters can be set within the range of 42-91 mm, and when filling large cavities and voids with viscous solutions - 91-110 mm.

7.41 In sandy rocks, instead of drilling wells, it is allowed to provide for driving (crushing) perforated injectors of various designs with a maximum immersion depth of up to 12-15 m. Immersion of injectors to greater depths should be provided for in drilled wells.

7.42 When designing injection curtains, the composition and pressure of the injected solutions, the dimensions of the fixed column (assessment of the permeability of rocks), as a rule, should be established according to experimental data. If they are absent, it is allowed to set the pressure based on data from the performance of the curtains under similar conditions.

The design documentation should provide for the necessary measures to prevent breakthroughs of injected solutions onto the surface of the earth or into mine workings (see 7.37).

7.43 The design documentation should provide for operational, acceptance, selective and other types of control over the processes of constructing the PFZ, its dimensions, continuity and characteristics of the material of the curtain body, which must be carried out using non-destructive (geophysical) methods, in combination with opening control pits, drilling out samples from fixed soil mass (composite) of the curtain body for further research in laboratory conditions, as well as the position of the groundwater level in front of and behind the curtain based on observation data from piezometric wells (clause 7.6).

The anti-filtration properties of the non-rocky and rocky rocks of the injection curtain fixed by cementation (filtration coefficient) can be determined by hydraulic testing through control wells in accordance with SP 23.13330 and taking into account the specific water absorption of the curtain body, considering the fixed massif of non-rocky rocks to be rocky rocks.

Ice curtains (fences)

7.44 Ice curtains, made by artificially freezing rocks, should be provided to protect underground (vertical, horizontal and inclined) mine workings during their excavation in non-rocky, unstable and fractured rocky aquifers.

With proper justification, it is permissible to provide for the use of ice curtains to protect open-pit mines during the development period.

7.45 The limits of applicability of rock freezing should be determined by calculation depending on the filtration rate, temperature and degree of mineralization of groundwater and freezing technology.

7.46 Ice curtains must be completely closed when driving underground mine shafts. To protect open workings, ice curtains can be closed (for small excavations), linear or contour open. The curtain must be buried in stable water-resistant rocks by at least 3 m.

7.47 The thickness of the ice curtain should be determined by static calculations depending on its purpose, the shape and size of the excavation in plan, depth, and the strength characteristics of frozen rocks.

7.48 The temperature of the ice curtain and the distance between freezing wells should be established on the basis of experimental data. In the absence of experimental data, it is allowed to accept:

the average temperature of the ice curtain is within 30-40% of the temperature of the coolant circulating in the freezing columns;

the distance between freezing wells with a single-row arrangement is within 1-1.5 m, between rows with a multi-row arrangement - within 2-3 m.

7.49 The capacity of the refrigeration unit should be determined by thermal engineering calculations depending on the design volume of the ice curtain.

7.50 To monitor the freezing process, monitoring wells should be installed - hydrogeological and thermometric. The design documentation should include a monitoring program that includes measures to control the temperature and level of groundwater, coolant temperature, rock temperature, as well as the continuity and thickness of the ice curtain, etc.

8 Regulation of surface runoff, drainage

8.1 When regulating surface runoff, the following should be provided:

drainage of water from quarry and, if possible, mine fields, watercourses and reservoirs;

fencing quarry and mine fields from water entering them from the adjacent territory;

elimination or reduction of infiltration of surface water into rocks in the zone of influence of water-reducing systems and drainage from mine workings, as well as large accumulations of water in low areas of the relief within mine (quarry) fields, including in troughs of displacement of the earth's surface;

planning the surface of the field territory with filling lakes, ravines, karst sinkholes and other depressions to prevent the accumulation of precipitation in natural depressions, installing the necessary drainage and rainwater network on the surface with the discharge of rainwater into watercourses outside the field territory;

prevention of destruction of the sides of the quarry (cut) and disruption of the normal conduct of operational work in it by surface water from atmospheric precipitation falling directly onto the area of ​​the open working, losses of process water, etc.

8.2 The design documentation for the system for regulating surface flow, depending on local conditions, should include upland ditches, enclosing dams, dams, drains and water intakes, straightening and diversion of rivers into a new channel, anti-filtration isolation of riverbeds within the mine (quarry) field and in the adjacent territory, as well as drains, discharge lines and catch basins in open workings, ensuring, together with the designed measures for protection from groundwater, the protection of mine workings from sudden breakthroughs of water and unacceptable inflows from water bodies and at the same time the protection of water bodies of national economic importance from harmful influence of mining workings.

8.3 The provision of calculated hydrological and meteorological characteristics for the design of hydraulic structures of protection systems must be established by the organization approving the terms of reference.

8.4 Refusal to protect underground mine workings from surface water must be justified, including the EIA section developed as part of the project documentation.

8.5 When designing a rainwater network within the upland ditches of a quarry or mine field, the influx of rainwater should be determined using the maximum intensity method. The period of one-time excess of the calculated rain intensity should be taken, as a rule, equal to 5 years, for especially critical objects or dangerous in relation to the stability of the sides of workings (in cases specifically specified in the design assignment) - 10 years.

Upland ditches should be designed based on a maximum flood flow of 5%.

Quarry water reservoirs and pumping stations should be designed based on the total inflow to the quarry, determined by the daily precipitation layer, with a period of its one-time excess, as a rule:

for quarry catch basins - 5 years,

for particularly critical facilities (in cases specifically specified in the design assignment) - for quarry water collectors - 10 years.

The supply of the quarry drainage pumping installation should be determined by the design, taking into account the pumping time from the reservoirs (or the volume of flooding) after the end of the estimated rain.

8.6 Permissible water velocities in drains should be assigned depending on the material of drain structures with a maximum flood flow rate of 5%.

Trays on slopes should be designed with a rectangular, trapezoidal or semicircular cross-section with fastenings that exclude the possibility of them being washed out by rainfall with a probability of 5%.

Ditches used as trench drainage should be designed with gentle slopes without fastening or with the slopes fastened with permeable material (perforated reinforced concrete slabs, rockfill, etc.).

Runoff interceptor trays should be provided at quarry ramps and descents. They should be covered with steel gratings that allow traffic to pass through.

8.7 All quarry runoff must be removed outside the quarry (cut) using drainage (see section 6). If relief conditions allow, the quarry drainage or part of it should be drained by gravity to the mine water discharge sites.

8.8 Out-of-pit and off-mine drainage devices may be made in the form of open ditches, trays, free-flow and pressure pipelines.

When designing out-of-pit and off-mine drainage devices, measures should be taken to prevent groundwater recharge within the zone of influence of water-reducing systems. If it is impossible to carry out these measures, when calculating water reduction, additional groundwater inflow due to recharge should be taken into account.

8.9 To prevent water from freezing in pipelines and pumps in winter, the following should be provided:

laying gravity pipelines with a slope of at least 0.005, and during long breaks in work - with a slope of 0.05-0.02;

installation of valves or valves to release water in low places in pressure pipelines;

installation of pumping units in heated rooms.

Additional measures to protect pipelines from freezing should be provided in accordance with thermal engineering calculations.

8.10 When discharging mine and quarry water onto the surface of the earth, into ravines, watercourses, reservoirs, as well as into water-absorbing layers, the requirements of Section 9 must be observed.

9 Security environment and measures for its implementation

9.1 When designing protection systems, protection of the natural environment should be taken into account by:

selection of design solutions for protection systems and constructive solutions for protective structures and devices that ensure the least damage due to depletion and pollution of groundwater, pollution, clogging, disruption of the regime and erosion of the banks of surface water bodies, erosion and soil erosion, swamping of the territory, displacement and deformations of rocks and the earth's surface, sediment and deformations of structures in the adjacent territory;

carrying out activities, as well as using structures and devices designed specifically for this purpose;

rational compensation for the damage caused.

Measures for the protection and protection of groundwater are justified by section 8 “List of environmental protection measures”, developed as part of the project documentation.

9.2 When designing the phased commissioning of water-reducing devices, one should not allow rapid development of water-reducing systems and a decrease in groundwater levels to a greater extent than provided for in 4.14 and 4.19.

It is necessary, as a rule, to differentiate between the pumping and drainage of clean and dirty water and to provide for the full or partial use of pumped water for water supply, agricultural purposes and other types of water use.

9.3 When designing the discharge of water pumped from dewatering devices and mine workings, as well as water discharged by gravity, it is necessary to comply with the requirements of the Federal laws of the Russian Federation: , , , and the regulatory legal acts adopted in their development.

The place of discharge of mine and surface water must be agreed upon with the interested organizations. The discharge location, excluding water bodies, is recommended to be located outside the depression zone of water-reducing devices.

Discharge of water pumped from dewatering devices and mine workings onto the surface of the earth, as a rule, is not allowed.

It is allowed to provide for the discharge of water onto unused lands, if this excludes the possibility of their entering water bodies, groundwater pollution, soil erosion, swamping of the area and other types of damage to the natural environment.

According to the Decree of the Government of the Russian Federation, an EIA section (environmental impact assessment) must be developed.

Project documentation is subject to environmental impact assessment on the basis of Federal Law.

9.4 When directly discharging mine water into water bodies, ravines and back into drained aquifers, if the requirements specified in 9.3 cannot be met, it is necessary to take appropriate measures aimed at preventing pollution of water bodies from suspended and dissolved substances contained in mine water .

9.5 To reduce the concentration of suspended substances, provision should be made for settling mine water in settling tanks. The capacity of the settling tank should be determined taking into account the volume of pumped mine water, the required settling time and the standard for the permissible discharge of clarified water into a water body, approved by the state examination. The conditions for the discharge of clarified water into a water body must be determined in accordance with 9.3, SP 32.13330 and taking into account. The settling time of mine water to achieve the required reduction in the concentration of suspended solids should, as a rule, be determined experimentally.

9.6 To reduce the concentration of pollutants, it is necessary to provide for the use of appropriate physicochemical and biological methods for purifying mine water. In any case, the standards for maximum permissible concentrations at the design site must be observed when discharging into a water body.

With appropriate justification, the treatment of mine water can be replaced by discharging it into evaporation storage tanks.

In some cases, in agreement with the authorities for regulating the use and protection of water, it is possible to design a storage device-regulator with the discharge from it (subject to the calculated standards of permissible discharges) of mineralized water into watercourses during a flood, subject to compliance with established standards maximum permissible concentrations (MPC) of substances in the water of water bodies at the design site in accordance with SanPiN 2.1.5.980.

Calculated standards for permissible discharges must undergo state examination.

9.7 Drainless depressions (depressions) or small lakes located near mining workings that do not have recreational, fishery or other national economic significance can be used as storage-regulators or storage-evaporators when these objects are provided for separate use on the basis of Federal laws and adopted in their development of normative legal acts. Karst sinkholes and sedimentation troughs are not allowed to be used as storage tanks-regulators and storage tanks-evaporators.

9.8 When designing storage tanks-regulators and storage tanks-evaporators, measures must be taken to eliminate the possibility of contamination of groundwater: installation of impervious curtains, screens, drainages, etc. The design documentation must provide for the installation of observation wells and a monitoring program.

Observation wells, depending on hydrogeological conditions, must be placed along the contour of storage tanks to monitor the level and degree of groundwater contamination in case of possible man-made leaks from drainage systems, violation of the integrity of impervious structures, etc.

Observation wells must be placed in such a way as to most fully characterize groundwater along the studied contour during the operation of the structure.

When studying several aquifers that may be affected by pollution (defined by project documentation), it is necessary to ensure that groundwater data is obtained for each aquifer. Monitoring must begin before installation of anti-filtration measures. Based on the results of the analysis of monitoring data, an assessment is made of the general condition of groundwater levels, starting from their natural position before the start of construction, as well as during the operation of the structure, it is possible to determine the location of leakage of water polluting aquifers, which allows taking measures to eliminate the leakage.

9.9 The design documentation should provide for the collection, removal and neutralization of mine water containing radioactive substances in accordance with current standards radiation safety And sanitary rules work with radioactive substances and other sources of ionizing radiation.

Discharge of mine waters containing radioactive substances onto the surface of the earth, into water bodies used for drinking, cultural and fishing purposes and into aquifers is not allowed.

9.10 The design documentation must provide for devices and measures to protect soils and banks of water bodies from erosion by pumped water.

9.11 The conditions for the discharge of mine water are indicated in the permit for special water use issued by the authorities for regulating the use and protection of water when allocating a site for the construction of a mining enterprise in accordance with Federal laws, and normative legal acts adopted in their development.

9.12 Based on the assessment of the quality of pumped water in the design documentation, decisions should be made on the extraction of useful components from them.

9.13 When designing anti-filtration devices and measures, it should be taken into account that in the area of ​​water intakes for domestic and drinking water supply, injection of water-soluble substances into aquifers is not allowed.

9.14 In the zone of influence of water-reducing systems, it is necessary to take into account possible subsidence of the earth’s surface, deformation and displacement of rocks, and determine additional movements of the foundations of structures.

9.15 Calculation of subsidence of the earth's surface at the base of structures with an expected decrease in groundwater levels should be made by summing the deformations of individual layers.

9.16 Under complex engineering and geological conditions of the construction site, it is recommended to use numerical modeling or engineering calculation programs and software packages to determine the subsidence, deformation and displacement of rock strata.

9.17 When designing water-reducing systems, it is necessary to take into account the possibility of the occurrence or activation of karst and karst-suffosion processes and loosening of soil at the base of buildings and structures, especially if the upper part of the soil layer is composed of sand. The design documentation should provide for appropriate measures to protect the foundations of existing and designed structures (sheet piling, rock clogging, cementation, etc.).

9.18 If it is impossible to fill the mined-out space of a quarry (cut) with rocks, it is allowed to provide for its reclamation by converting it into a reservoir for various types water use.

If you are a user of the Internet version of the GARANT system, you can open this document right now or request by Hotline in the system.

BUILDING CODES AND RULES

PROTECTION OF MINING WORKS FROM UNDERGROUND
AND SURFACE WATER

SNiP 2.06.14-85

USSR STATE COMMITTEE FOR CONSTRUCTION

MOSCOW 1985

DEVELOPED BY GPI Foundation Project Ministry of Montazhspetsstroy USSR (engineers M.L. Morgulis - topic leader G.G. Golubkov, D.P. Efimovich, V.K. Demidov, A.V. Ilyin, I.S. Rabinovich, L.I. Ivanova, Yu.N Egerev, A.D. Neklyudov) VIOGEM Ministry of Ferrous and Metallurgy of the USSR (candidates of technical sciences) E.S. Gledchenko,G.M. Krastoshevsky, V.M. Drag; engineers Yu.I. Lyapin, L.D. Zakharov), NIIOSP named after. Gersevanov of the USSR State Construction Committee (eng. A.B. Meshchansky; Doctor of Engineering sciences M.I. Smorodinov, K.E. Egorov; candidates of technical sciences IN.N. Korolkov, V.T. Ternovskaya), VNII VODGEO of the USSR State Construction Committee (candidate of technical sciences) V.M. Grigoriev), Giprotsvetmet by the USSR Ministry of Tsvetmet (engineers S.V. Parmuzin, V.E. Lurie) with the participation of the design office of the Shakhtspetsstroy trust and the Soyuzshakhtoosushhenie trust of the USSR Ministry of Montazhspetsstroy (engineers Ya.I. Feigin,E.V. Olizarevich, L.N. Moscow), VSEGINGEO Ministry of Geosciences of the USSR (Doctor of Geological Mineralogical Sciences V.N. Golberg; Ph.D. geol. mineralogist. sciences N.IN.Sokulina), VNIIVO Ministry of Water Resources of the USSR (candidate of technical sciences) V.N.Ladyzhensky).

INTRODUCED by the USSR Ministry of Montazhspetsstroy.

PREPARED FOR APPROVAL BY Glavtekhnormirovanie Gosstroy USSR (eng. V.A. Kulinichev).

When using a regulatory document, one should take into account the approved changes to building codes and regulations and state standards published in the journal “Bulletin of Construction Equipment of the State Committee for Construction of the USSR and Information Index” State standards USSR" Gosstandart.

These standards apply to the design of protection from groundwater and surface water (hereinafter referred to as protection) of mine workings using water reduction, dewatering, anti-seepage curtains and regulation of surface flow during open-pit and underground mining of solid mineral deposits.

1. BASIC PROVISIONS

GENERAL INSTRUCTIONS

1.1. When designing, it is necessary to proceed from the fact that the protection of mine workings should:

prevent water inflows into workings that violate the conditions of normal field development;

prevent water breakthroughs into workings;

prevent dangerous destruction by water of rocks surrounding the workings;

ensure organized drainage of surface and mine waters to the places of their discharge;

to prevent depletion of groundwater resources and their pollution, clogging, disruption of the regime and erosion of the banks of surface water bodies, erosion of the soil layer and dangerous consequences of deformation of rocks and structures in the area of ​​protected workings as a result of lowering the groundwater level;

provide structures, devices and measures to regulate the inflow to workings, groundwater pressure and surface runoff in the area of ​​the mine being developed, for the drainage of pumped mine water and environmental protection.

1.2. The choice of types and systems for protecting mine workings, types of protective structures, devices and measures should take into account the production and natural conditions that change over time as the mine is developed, the shape and size of the protected space.

Protection systems, their development, designs of protective structures and devices, protective measures must be interconnected with systems, methods and development of field development.

The considered options for the protection of mine workings should be assessed and compared taking into account the duration of use of protective structures, devices and measures, the conditions created for the development of the deposit, the impact on the environment and the total costs of protection during the construction and operation of a mining enterprise.

When comparing options for water reduction and anti-seepage curtains, it is necessary to take into account the differences between quarry and mine drainage in both cases, as well as the fact that anti-seepage curtains, unlike water reduction, do not entail the formation of harmful runoff and depletion of groundwater resources and do not cause deformation of rocks, the earth's surface and structures in the area of ​​protected objects. At the same time, it is necessary to take into account the disruption they cause to the natural movement of groundwater, which remains even after the liquidation of a mining enterprise.

1.3. Anti-filtration curtains may be provided as the main means to prevent the flow of groundwater into mine workings from the outside and as an auxiliary measure for solving local problems of eliminating local filtration centers.

1.4. The initial data for design should include requirements for the system for protecting mine workings from groundwater and surface water, information about designated mine water discharge sites and survey materials.

Survey materials must meet the requirements of SNiP II-9-78 and contain:

hydrological and meteorological data;

topographic plans of the field area on a scale established by the design organization;

characteristics of the geological structure, tectonic disturbance of strata, neotectonics, seismic conditions and special conditions(presence of permafrost, karst, landslide phenomena, etc.);

geological sections and profiles;

characteristics of hydrogeological conditions, engineering-geological characteristics and information on the physical and mechanical properties of rocks; information about aquifers, sources and areas of their recharge and discharge, the relationship between them and with surface waters, their chemical composition, temperatures;

data on the filtration properties of rocks, determined using experimental pumping and taking into account the schematization of hydrogeological conditions;

maps of the distribution of aquifers, the relief of their roof and base, as well as hydroisohypsum and waterproofing.

Geological and hydrogeological data must be covered within the expected zone of depression and to a depth covering all aquifers from which filtration or breakthrough of groundwater into the mine opening is possible.

1.5. In mining protection projects, except technical documentation, which meets the requirements of current regulatory documents for the preparation of projects and estimates approved in the prescribed manner, must provide the characteristics of agricultural land, as well as existing and constructed structures and enterprises that may be affected by the designed protective measures, information about the methods, sequence and timing of field development and solutions for protecting the natural environment are given.

1.6. Projects should provide for the phased implementation of the designed protection system.

In conditions where, based on survey materials, it is not possible to make sufficiently substantiated calculations or to finally select a protection system, the design of its structures and devices, the project should include pilot production work, the results of which are used to adjust the project.

1.7. Calculations should determine:

decrease in groundwater levels at characteristic points, time to achieve the required decrease, inflows of groundwater and surface water to water-reducing devices and into mine workings - according to the stages of field development;

groundwater inflows through anti-filtration curtains, curtain thickness, position of groundwater levels on both sides of the curtain;

the required number of wells for anti-filtration curtains and the consumption of materials for them, the distribution of initiated materials in the rock mass, the required time to create stable anti-filtration curtains;

productivity, throughput, dimensions, number, placement and other parameters of devices for water reduction, water collection, drainage, anti-filtration curtains and implementation of anti-filtration measures; the need for material and energy resources; assessment of the quality of pumped water and possible changes in the quality of ground and surface water; assessment of damage to river flow, agriculture and forestry, water supply to settlements and enterprises from the operation of water-reducing devices.

In addition, during design it is necessary to determine the expected deformations of the earth's surface in the zone of influence of water-reducing systems.

If necessary, it is allowed to use modeling and justify the calculated values ​​with experimental data.

1.8. Projects should include the installation of observation wells and posts, geodetic benchmarks, marks and surveying points, the installation of control and measuring equipment and the period for putting them into operation for conducting hydrogeological, hydrological, surveying and geodetic observations, as well as observations of the operation of protection system devices during their construction and operation.

The composition and mode of necessary observations must be established in the project. Observations should be made of the levels, temperature, chemical and gas composition of groundwater, air temperature, amount of precipitation, water levels in reservoirs, flow rate, temperature, chemical and gas composition of pumped water, deformation of rocks and the earth’s surface, precipitation and deformation of structures .

DESIGN OF OPEN MINING PROTECTION

1.9. Open pit mine protection projects should include:

external structures and measures to regulate surface runoff in the area adjacent to the quarry (mine);

in-quarry devices and measures designed for the influx of groundwater entering the quarry and the drainage of surface water collected in it: drains, catch basins, drainage installations or devices for discharging water from catch basins into underground workings and, if necessary, depending on local conditions - in-quarry borehole and wellpoint water reduction installations, local grouting of rocks, drainage, loading of slopes;

external drainage devices for discharging quarry water.

1.10. If necessary, due to the conditions for ensuring the stability of the sides of the workings or due to production conditions, reducing the influx of groundwater into the quarry (cut trench, exit trench, etc.), the project, in addition to the devices and measures provided for in clause 1.9, should include contour ring or partial ring and linear external water-reducing systems or impervious curtains.

Ring water-reducing systems should be provided when aquifers spread throughout the entire protected area and beyond.

Non-full-ring water-reducing systems should be designed when aquifers do not spread from all sides of the protected area.

Linear water-reducing systems should be designed to intercept one-way underground flow from the side of a reservoir (watercourse) or along a layer that has a pronounced slope towards the protected area, as well as to protect extended workings and in cases where local conditions make their use advisable.

1.11. Ring, partial ring and linear impervious curtains should be designed in the same cases as the corresponding water-reducing systems (see clause 1.10), taking into account restrictions for the use of certain types of curtains due to natural conditions (according to the instructions of Section 4) and local production capabilities.

1.12. With appropriate justification, water-reducing and anti-filtration devices of quarries (cuts) may be provided in the form of separately located elements of the protection system, placed according to the condition of their greatest efficiency and taking into account the topography of the underlying aquifer, the occurrence of rocks with high water permeability, the direction of underground flow, etc.

1.13. Reducing the piezometric level of pressure water to maintain the stability of rocks and prevent water breakthrough into workings can be provided using devices specially designed for this purpose (wells equipped with pumps, self-flowing wells, etc.).

1.14. When designing a quarry (cut) protection system carried out in several stages, it is necessary to provide for:

before the start of construction of a quarry (mine) - commissioning of external structures and devices to regulate surface runoff and drainage, commissioning of structures, devices and implementation of measures necessary to protect mine workings from groundwater for the period during which the structures can be prepared , devices and activities of the next stage. During the same period, when designing a protection system with external water-reducing or anti-filtration devices, the rapid development of a decrease in the groundwater level or advanced anti-filtration devices must be ensured; when designing a mine workings protection system without external devices, the availability of funds for carrying out the necessary measures and performing the necessary devices in the process development of a quarry (cut);

during the construction of a quarry (mine) - sequential commissioning of additional structures and devices and carrying out the necessary measures provided for by the project (see paragraphs 1.10-1.13);

by the time the quarry (mine) is put into operation - the readiness of structures and devices that ensure the protection of mine workings until the full design productivity of the quarry (mine) is achieved, including the readiness of the designed system for regulating surface runoff, drainage, stationary drainage and drainage of mine water;

during the operation of the quarry - the sequential commissioning of structures and devices and the implementation of measures designed in the protection system and ensuring a constant advance in relation to mining operations in the development of lowering the level of groundwater or impervious devices for the period provided for in the project.

DESIGN OF UNDERGROUND MINING PROTECTION

1.15. In projects for the protection of underground workings, depending on local conditions within the mine field, the use of:

as underground drainage - the protected workings themselves with the installation of drainage grooves in them;

vertical, horizontal and inclined self-flowing wells, drilled, crushed (or driven) from the protected workings themselves, drainage workings and from special niches and chambers;

through filters, drilled from the surface and driven into the protected or drainage workings themselves;

wells equipped with pumps and constructed from the surface or from underground workings; wellpoint filters in underground mines; anti-filtration curtains (rock grouting);

appropriate structures and measures to regulate surface runoff, including water accumulating in troughs of displacement of the earth's surface.

In all cases, projects for the protection of underground workings must provide devices and installations for drainage and drainage of pumped water to places of discharge.

Note. The surface flow control system, if necessary, should cover the territory outside the mine field within the limits established by the project.

1.16. In cases of an immediate threat of breakthroughs in underground workings of water and rocks, in particular when rock aquifers lie above the roof of a mineral deposit, it is allowed, with appropriate justification, to include in the project off-mine water-reducing systems and impervious curtains, installed in accordance with the requirements of paragraphs. 1.10-1.13.

The permissible amount of water inflow into the development and treatment workings at mineral deposits should be taken based on the experience of constructing and operating mines under similar conditions.

1.17. When designing the protection of mine workings passing through an aquifer, from which significant inflows of water are expected, it is allowed, with proper justification, to provide for the creation of special drainage horizons within the mine field, placing drainage workings below the main haulage horizons.

1.18. When designing the protection of mine workings, it is necessary to take into account that their excavation in undrained rocks should be provided with advanced drilling and compliance with the requirements of clause 1.15, and, in necessary cases, with preliminary freezing of rocks or using the shield method.

1.19. When designing an underground mine protection system carried out in several stages, it is necessary to provide for:

before the start of shaft sinking - commissioning of structures and devices for regulating surface runoff enclosing the sites of mine shafts, drilling of advanced control exploration wells to the entire depth of the shaft, readiness of external shaft impervious curtains or water-reducing systems (if they are provided for by the project), readiness for preliminary plugging of rocks ;

before the start of excavation of preparatory workings - commissioning of a drainage installation at the mine shaft (it is allowed to provide for the excavation of preparatory workings with the operation of a temporary pumping station, designed for the expected influx in the period until the planned stationary pumping station is ready); commissioning of sump and pumping stations and off-mine water reduction systems (if they are provided for by the project);

during the period of excavation of preparatory workings - sequential commissioning of additional structures and devices and carrying out the necessary measures provided for by the project (see paragraphs 1.16-1.18);

by the time of the start of cleanup work - the development of a decrease in the level of groundwater, the readiness of structures and devices that ensure the protection of underground workings until the full design productivity of the enterprise is achieved, including the readiness of stationary underground pumping stations and systems for regulating surface runoff and drainage;

during the operation of the enterprise - further sequential commissioning of the designed structures and devices and implementation of measures that ensure constant advance (in relation to mining operations) development of lowering the level of groundwater or corresponding impervious devices for the period determined by the project.

2. WATER REDUCTION

2.1. Water reduction should be designed using open and vacuum dewatering wells, wellpoints, reservoir, trench and tubular drainages, and underground drainage workings.

2.2. The required amount of pressure reduction in aquifers should be determined from the condition of maintaining the stability of the rocks surrounding the workings and preventing the breakthrough of groundwater into them.

2.3. When designing a water reduction system using an external water reduction system that protects an open mine, the groundwater level should be lowered, if possible, below its bottom by an amount determined by the calculated increase in the water level during an emergency shutdown of the water reduction system.

If it is impossible to lower the groundwater level below the bottom of an open pit, in particular when it crosses aquifer layers, it is necessary to proceed from the practically achievable depth of water decline in each aquifer and provide additional in-pit devices and measures in accordance with clause 1.9.

2.4. When designing water reduction using off-mine water reduction devices that protect underground mine workings in aquifers that are not separated by an aquitard from the overlying aquifers, the reduced groundwater level must be below the base of the protected underground workings to a depth that meets the requirements of clause 2.3.

If there is an aquitard (rocks with a filtration coefficient of less than 0.001 m/day), separating the rock mass in which underground workings are designed from the overlying aquifer, a decrease in the groundwater level in this layer can be prescribed, taking into account compliance with the condition

Where at- residual pressure measured from the roof of the separating layer of water-resistant rocks, m;

h d- thickness of the separating layer of waterproof rocks not disturbed during development, m.

At the same time, the requirement to lower the groundwater level in the rock mass where underground mine workings are located, below their base, remains in force.

If it is impossible to lower the groundwater level below the bottom of the mine workings using external mine water-reducing devices, it is allowed, with appropriate justification, to use them for practically achievable water reduction, providing devices and measures within the mine field in accordance with clause 1.15.

2.5. The required time to achieve the required reduction in groundwater levels, the spread of depression and the development of the water reduction system should be determined according to the mining plan.

2.6. The schematization of natural conditions for calculating water reduction should reflect the actual hydrogeological conditions, the geological structure of the strata and the characteristics of its constituent layers.

2.7. Calculation of water reduction, as a rule, should be performed based on the linear filtration law expressed by the formula

Where v- filtration rate, m/day;

k- filtration coefficient, m/day;

I- pressure gradient.

Basic calculation formulas and tables are given in recommended Appendix 1.

If it is necessary to use water reduction in aquifers composed of rocks characterized by high filtration properties (coarse clastic, highly fractured and karst), the calculation of water reduction can be based on experimental data and clarified during the stage-by-stage implementation of the protection system.

2.8. For conditions of increased complexity (non-uniform filtration flow, complex contours of supply and water reduction circuits, etc.), the calculation of water reduction systems can be carried out using modeling or other methods.

2.9. The designs of water-reducing and observation wells and drainages should be adopted in accordance with the instructions of mandatory Appendix 2.

PROTECTION OF MINING WORKS FROM UNDERGROUND

AND SURFACE WATER

SNiP 2.06.14-85

OFFICIAL PUBLICATION

DEVELOPED BY GPI Foundation Project Ministry of Montazhspetsstroy USSR (engineers M.L.Morgulis - topic leader G.G.Golubkov, D.P.Efimovich, V.K.Demidov, A.V. Ilyin, I.S. Rabinovich, L.I. Ivanova, Yu.N Egerev, A.D. Neklyudov) VIOGEM Ministry of Ferrous and Metallurgy of the USSR (candidates of technical sciences) E.S. Gledchenko, G.M. Krastoshevsky,V.M.Drag; engineers Yu.I.Lyapin, L.D. Zakharov). NIIOSP named after. Gersevanov of the USSR State Construction Committee (eng. A.B. Meshshansky; Doctor of Engineering sciences M.I. Smorodinov, K.E. Egorov; candidates of technical sciences IN.N. Korolkov, V.T. Ternovskaya). VNII VODGEO of the USSR State Construction Committee (candidate of technical sciences) V.M. Grigoriev). Giprotsvetmet by the USSR Ministry of Tsvetmet (engineers S.V. Parmuzin, V.E. Lurie) with the participation of the design office of the Shakhtspetsstroy trust and the Soyuzshakhtoosushhenie trust of the USSR Ministry of Montazhspetsstroy (engineers Ya.I. Fagin, E.V. Olizarevich , L.N. Moscow). VSEGINGEO Ministry of Geosciences of the USSR (Doctor of Geol.Mineralogical Sciences V.N. Golberg; Candidate of Geol.Mineralogical Sciences N.IN. Sokupina). VNIIVO Ministry of Water Resources of the USSR (candidate of technical sciences) V.N. Ledyzhensky)

INTRODUCED by the USSR Ministry of Montazhspetsstroy.

PREPARED FOR APPROVAL BY Glavtekhnormirovanie Gosstroy

USSR (eng. V.A. Kulinichev)

These standards apply to the design of protection from groundwater and surface water (hereinafter referred to as protection) of mine workings using water reduction, dewatering, anti-filtration curtains and regulation of surface flow in open-pit and underground mining of solid mineral deposits.

1. Basic provisions general instructions

1.1. When designing, it is necessary to proceed from the fact that the protection of mine workings should:

prevent water inflows into workings that violate the conditions of normal field development;

prevent water breakthroughs into workings;

prevent dangerous destruction by water of rocks surrounding the workings;

ensure organized drainage of surface and mine waters to the places of their discharge;

to prevent depletion of groundwater resources and their pollution, clogging, disruption of the regime and erosion of the banks of surface water bodies, erosion of the soil layer and dangerous consequences of deformation of rocks and structures in the area of ​​protected workings as a result of lowering the groundwater level;

provide structures, devices and measures to regulate the inflow to workings, groundwater pressure and surface runoff in the area of ​​the mine being developed, for the drainage of pumped mine water and environmental protection.

1.2. The choice of types and systems for protecting mine workings, types of protective structures, devices and measures should take into account the production and natural conditions that change over time as the mine is developed, the shape and size of the protected space.

Protection systems, their development, designs of protective structures and devices, protective measures must be interconnected with systems, methods and development of field development.

The considered options for the protection of mine workings should be assessed and compared taking into account the duration of use of protective structures, devices and measures, the conditions created for the development of the deposit, the impact on the environment and the total costs of protection during the construction and operation of a mining enterprise.

When comparing options for water reduction and anti-seepage curtains, it is necessary to take into account the differences between quarry and mine drainage in both cases, as well as the fact that anti-seepage curtains, unlike water reduction, do not entail the formation of harmful runoff and depletion of groundwater resources and do not cause deformation of rocks, the earth's surface and structures in the area of ​​protected objects. At the same time, it is necessary to take into account the disruption they cause to the natural movement of groundwater, which remains even after the liquidation of a mining enterprise.

1.3. Anti-filtration curtains may be provided as the main means to prevent the flow of groundwater into mine workings from the outside and as an auxiliary measure for solving local problems of eliminating local filtration centers.

1.4. The initial data for design should include requirements for the system for protecting mine workings from groundwater and surface water, information about designated mine water discharge sites and survey materials.

Survey materials must meet the requirements of SNiP II-9-78 and contain:

hydrological and meteorological data;

topographic plans of the field area on a scale established by the design organization;

characteristics of the geological structure, tectonic disturbance of strata, neotectonics, seismic conditions and special conditions (presence of permafrost, karst, landslide phenomena, etc.);

geological sections and profiles;

characteristics of hydrogeological conditions. engineering-geological characteristics and information about the physical and mechanical properties of rocks; information about aquifers, sources and areas of their supply and discharge, the relationship between them and with surface waters, their chemical composition, temperatures;

data on the filtration properties of rocks, determined using experimental pumping and taking into account the schematization of hydrogeological conditions;

maps of the distribution of aquifers, the relief of their roof and base, as well as hydroisohypsum and waterproofing.

Geological and hydrogeological data must be covered within the expected zone of depression and to a depth covering all aquifers from which filtration or breakthrough of groundwater into the mine opening is possible.

1.5. In mining protection projects, in addition to technical documentation that meets the requirements of current regulatory documents for the preparation of projects and estimates approved in the established order, the characteristics of agricultural land, as well as existing and constructed structures and enterprises that may be affected by the designed protective measures, information must be given about the methods, sequence and timing of field development and decisions are given to protect the natural environment.

1.6. Projects should provide for the phased implementation of the designed protection system.

In conditions where, based on survey materials, it is not possible to make sufficiently substantiated calculations or to finally select a protection system, the design of its structures and devices, the project should include pilot production work, the results of which are used to adjust the project.

1.7. Calculations should determine:

decrease in groundwater levels at characteristic points, time to achieve the required decrease, inflows of groundwater and surface water to water-reducing devices and into mine workings - according to the stages of field development;

groundwater inflows through anti-filtration curtains; thickness of the curtain; position of groundwater levels on both sides of the curtain:

the required number of wells for anti-filtration curtains and the consumption of materials for them, the distribution of initiated materials in the rock mass, the required time to create stable anti-filtration curtains;

productivity, throughput, size, number, placement and other parameters of devices for water reduction, water collection, drainage, anti-filtration curtains and implementation of anti-filtration measures: the need for material and energy resources; assessment of the quality of pumped water and possible changes in the quality of ground and surface water; assessment of damage to river flow, agriculture and forestry, water supply to settlements and enterprises from the operation of water-reducing devices.

In addition, during design it is necessary to determine the expected deformations of the earth's surface in the zone of influence of water-reducing systems.

If necessary, it is allowed to use modeling and justify the calculated values ​​with experimental data.

1.8. Projects should include the installation of observation wells and posts, geodetic benchmarks, marks and surveying points, the installation of control and measuring equipment and the period for putting them into operation for conducting hydrogeological, hydrological, surveying and geodetic observations, as well as observations of the operation of protection system devices during their construction and operation.

The composition and mode of necessary observations must be established in the project. Observations should be made of the levels, temperature, chemical and gas composition of groundwater, air temperature, amount of precipitation, water levels in reservoirs, flow rate, temperature, chemical and gas composition of pumped water, deformation of rocks and the earth’s surface, precipitation and deformation of structures .