METHODS TO USE FOR TECHNICAL REHABILITATION

Sequence of rehabilitation work

The technical rehabilitation area will be divided into segments, and rehabilitation work in each section will be carried out in the following order.

Lake and pond dewatering – Performs dewatering of lakes, ponds, and water in depressions created for technological purposes. The rehabilitation area will be divided into sections, and the first task will be to dewater the lakes and ponds within each section. This will protect the sections from mudslides, landslides, and collapses, and will determine the depth of the lakes and ponds and the scope of the work. This work is done by digging trenches with an excavator, breaking dams to drain the water, and if this is not possible, installing a pump to remove the water.

Risks: Excavator getting stuck in mud, getting stuck in a pond, or sliding into a pond – to prevent this, first select a trenching route, level the area where the excavator will work, and prepare an exit immediately in case of any landslides, then begin trenching and damming. When digging a trench, start at the lowest point where water flows and then pull it up towards the pond. This will help to dig the trench without water and reduce the risk of the trench collapsing. The excavator operator will identify and secure any areas at risk of collapse during trench digging. Finally, the lake water will be connected to the ditch and drained, and a direct exit will be prepared for the excavator itself. When approaching the lake, carefully inspect the surface for any cracks and determine if a collapse is likely, then prepare a direct exit. The excavator chain should be positioned at a 90-degree angle to the bank of the lake to approach, and if there are signs of the bank collapsing, it is immediately withdrawn.

When installing a pump, there are risks such as the pump hose breaking, the pump foundation collapsing, the cable breaking during the pump lifting process, and electric shock. To prevent this, select a location where the hose is laid, the pump is installed, and the generator is placed so that it will not collapse, slide, or be crushed by the ground, and level the work area with an excavator or bulldozer and prepare the slope to prevent collapse. After that, the pump, generator, hose, etc. are lifted into place. When lifting, first check the load capacity and risk of breakage of the rope, pulley, and lifting hook. After these are installed, an electrician will make the electrical connections, and the electrical cord connecting the generator pump will have a dedicated end cap at the beginning and end, which will not be connected to any load. Additionally, the generator and pump should have a grounding device on them. This work will be carried out under the supervision of the foreman according to the instructions. The generator pump will be operated by the pump operator.

Spreading and tilting piles and embankments– The foreman will first assess the embankments or piles and decide whether to use a bulldozer or excavator. If the side slopes of the pile or embankment are too steep (over 60 degrees), there are overhangs, cracks along the side slopes, or the working area on the pile or embankment is small, these should be made safe by an excavator without using a bulldozer, and then the pile or embankment should be spread out according to standards using a bulldozer.

Risks: During this work, excavators and bulldozers face risks such as slipping, pile collapse, collisions when two or more machines are working on the same pile or embankment, and getting stuck in the mud. To prevent this, measures must be taken to prevent slipping when moving the excavator up and down the pile or embankment, and the road must be prepared so that the slope of the road does not exceed that specified in the excavator’s technical operating documents. Keep a clear path for emergency exit from piles and embankments. When approaching the edge of a pile or embankment, position the chain so that it is at a 90-degree angle to the edge, and if there is a crack along the edge, it is prohibited to cross the crack. The slope of the edge should be adjusted to the angle of the soil’s own collapse, the working area should be leveled by throwing it to the bulldozer, and if it is high, it should be lowered and thrown before the bulldozer is used. Excavators and bulldozers should work and travel at a distance of more than 2m along the edge of the pile or embankment. When technicians are working on the same pile or embankment, they must not enter each other’s working radius and establish positive communication through the station. In the event of getting stuck in mud, notify the foreman and take measures such as digging and pulling according to the foreman’s instructions. In case of mud jam, notify the foreman and take measures such as digging and pulling according to the foreman’s instructions. If pulling is necessary, use steel ropes of the appropriate load capacity.

Backfilling- The foreman will first assess the excavation and the drained lake or pond and decide whether to use a bulldozer or excavator. If the side slopes of the trench are too steep (over 60 degrees), deep, have a slope, or have cracks along the side slopes, these should be made safe by an excavator without using a bulldozer, and then the trench should be filled and graded according to standards using a bulldozer.

Risks: During this work, excavators and bulldozers are exposed to risks such as slipping, collapsing of the side bank, collisions while the equipment is working, and getting stuck in the mud. To prevent this, keep the excavator clear to exit the excavation immediately. When approaching the bank of the ditch, place the chain so that the edge is at a 90-degree angle to it. If there is a crack along the bank, it is forbidden to cross the crack. If the bank has formed a ridge or is too steep, the bank is thrown and tilted until the angle of the soil collapses. If there is a crack along the shore, after taking measures to make the crack safe by demolishing it or filling the crack and making it safe, a bulldozer will be brought into the work area. Excavators and bulldozers will work more than 2m along the shore. When filling the excavation, the bulldozer will be positioned at a 90-degree angle to the shore and will be filled. When filling the trench, the bulldozer is positioned at a 90-degree angle to the bank and will use pressure. During the filling process, if the surface is dry and non-slip, a wheel loader will be used. When the technicians are working, they will not enter each other’s working radius and will establish positive communication with the station. In case of mud jam, notify the foreman and take measures such as digging and pulling according to the foreman’s instructions. If pulling is necessary, use steel ropes of the appropriate load capacity.

River and stream bank restoration and stream bank slope repair- This operation is relatively safe. The dry land, river and stream channels of the damaged land shall be restored close to their original location, and the slope of the restored channel shall not exceed 25 degrees. If the river or stream channel is very dry and the embankment material is unable to enter the river or stream, use a bulldozer or wheel loader to push and tilt it. If the embankment is in contact with the river or stream, use an excavator to tilt the embankment and pull the material out and dilute it according to the environment.

Risks: To prevent risks such as riverbank collapse, collisions, and mudslides while equipment is operating, excavators, bulldozers, and wheel loaders are to be positioned at a 90-degree angle to the riverbank. Technicians will work at a distance of more than 2m along the shore. Technicians will not be within each other’s working radius while working, and will establish positive contact with the station if necessary. In case of mud jam, notify the foreman and take measures such as digging and pulling according to the foreman’s instructions. If pulling is necessary, use steel ropes of the appropriate load capacity.

Shaping 

After the above tasks are completed, the area being rehabilitated is shaped to resemble its natural state. This work usually involves the use of bulldozers, wheel loaders, and, where necessary, excavators.

Risks: When operating machinery, there are risks such as collisions and mudslides, and the above-mentioned measures will be implemented.