02.02.2024

 

Search and rescue operations at the mine Maikainzoloto, risks and international experience of implementation.

 

 

 

Circumstances of the emergency and group accident that occurred on January 4, 2024 at the mine of JSC "Maikainzoloto".

 

Brief reference from the Act of special investigation of a group labor-related accident due to an emergency (collapse of the topsoil layer), which occurred on January 04, 2024 at the mine of JSC "Maikainzoloto":

 

04.01.2024 at about 01.00 am on the territory of MUMC JSC there was a collapse of the topsoil layer into the mine cleaning space with subsequent escape to the surface.

 

According to the scheme of dump trucks movement, available in the approved and valid from 01.07.2021 TR for loading and delivery works of rock mass by road transport from Maikain site to MC, there is a section of technological road in the collapse zone.

 

At 01:14 am the 1st Mine rescue department of Maikain MERP of Pavlodar branch of LLP "CRH MPERS" (hereinafter - the department) consisting of four people left on the operational bus TAVZ 3270, g/n number 295AU14 on the reconnaissance of the fire (position № 9 ARP for the 1st half of 2024).

 

At 01:17 am the 2nd squad consisting of four people left on the fire truck AC-40 to extinguish the fire (position No. 9 of the ARP for the 1st half of 2024).

 

While driving an operational bus TAVZ-3270 g/n 295AU14, on the technological highway to the area of the suspected fire, the bus with the rescuers inside fell into an existing dip.

The boundaries of the resulting slump were unstable and the area was cordoned off.

 

The forces of the Emergency Situations Department of Pavlodar region (units from Pavlodar and Ekibastuz) together with PF (professional formations) of "CRH MPERS" LLP started search and rescue works.

 

The main dangerous production factor that led to the group accident was the collapse of the upper ground layer into the mine clearing space.

 

 

Causes of the accident

 

The Commission, having considered the documentation, conclusions of expert organizations, subcommissions and interviews with eyewitnesses concluded that the causes of the group accident due to the collapse of rock mass into the mined-out space are:

 

1. Unsatisfactory organization of works, which was expressed in the following: -

Production control over safe mining operations was not properly controlled by the responsible persons of JSC Maikainzoloto.

 

2. Control over the process of caving from the mine workings during block mining was not carried out properly.

 

3 There were no (not developed) projects for mining of excavation units (block) during mining of ore body II above and below horizon +90м (160).

 

Search works

 

Search work has been going on since January 4, 2024 around the clock. Two dead rescuers were found on the first day.

 

About 170 people were involved in the search operations, more than 40 units of various machinery, special equipment - geoscanners, magnetometers, three canine teams, two UAVs.

 

  

 

The dimensions of the cave-in (surveyor data) initially amounted to 176m in length, 130m in width and 67m in depth. Over time, the dimensions of the collapse have changed insignificantly.

 

 

Soil was removed to lay a path for small-sized equipment to the site of the accident.

 

  

 

More than 200,000 cubic meters of earth and rock have been moved at the site of the collapse, including to make a slope to the suspected location of the people.

 

  

 

Heavy equipment laid a side ramp to the edge of the excavation, which allowed the small excavator to descend to the location of the bus.

 

The movement and fall of rock mass pieces are monitored from the edge of the funnel 24 hours a day.  At the initial stage, geo-scanning was carried out by specialists of JSC AK Altynalmas to coordinate the direction of excavators.

 

      

 

Then, to continue geoscanning, a crane was installed, with its help specialists of Qazaq Geophysics JSC Kazakhmys LLP and rescuers went down to the site and surveyed the formed dump with special equipment to search for voids, metal and other anomalies.

 

 

 

Subsequently, geo-scanning was carried out by specialists of GRP Ridder Group LLP, including the use of a drone.

 

  

 

 

Rescuers constantly provide insurance and safety for two excavators and other specialists at the bottom of the sinkhole. Fuel, food, specialists - surveyors, as well as the lifting of found objects is carried out with compliance with safety rules. 

 

  

 

Multiple fragments of the bus and personal equipment of the rescuers were brought to the surface from the excavation site.

 

  

The small excavator moved about 850 cubic meters of soil, allowing more space for the second excavator to operate.

 

With the help of two bulldozers, vertical and horizontal insurance, lowered the second small excavator with the driver.

 

   

 

Complexities of the search operation and risks to its continuation

 

The search operation is complicated by weather conditions - sub-zero temperatures and strong winds, extremely unstable soil conditions, constant crumbling of soil from the slopes of the sinkhole, and possible voids under it, which increases the risk of further collapses and, accordingly, there is a huge risk for the rescuers themselves - to fall down even deeper, then it will be necessary to conduct another rescue operation.

 

The main problem is not in the lack of forces and means, there is enough equipment and personnel working at the scene, but in determining the actual location of the victims.

The small-sized equipment used (mini excavator - IHI50Z, bucket volume 0.25m3) has to work under large boulders (larger than the excavator itself) actually on a stretch on cables, which are secured on the surface by two heavy bulldozers and an excavator.

The bucket volume of the excavator is small, so the volume of rock mass extraction is also insignificant, which delays the search process. And heavier equipment cannot be used.

 

The excavator himself is insured with ropes by MES and CRH MPERS rescuers, periodically interchanged each other.

 

 

Cracks on the surface and in the collapse zone can also lead to further collapse of the rock mass.

Currently, there is scree along the sides of the crater. There is a risk of large boulders collapsing. Rescuers, excavator operators and specialists from various services working at the bottom of the crater are at risk. Due to the existing voids under the bottom of the funnel, the probability of failure is high.

 

 

Consulting with foreign partners

 

Given the seriousness of the situation, the Association of Emergency Rescue Services of the Republic of Kazakhstan (accredited by the Ministry of Emergency Situations of the Republic of Kazakhstan and the International Mine Rescue Body IMRB) consulted with foreign partners - leading professional emergency rescue ( mine rescue) services on the expediency of further search operations and assessment of the actions of Kazakh rescuers.

 

Reviews of foreign experts on the actions of rescuers from Kazakhstan - are positive. A enormous amount of work was noted, with the involvement of maximum forces and means. 

 

But, all foreign experts note the high risk of further work to search for the remaining two people, as work at the site is complicated by the extremely unstable state of the soil, the constant crumbling of soil from the slopes of the funnel, and possible voids under the funnel, which increases the risk of further collapses and, consequently, the risk to rescuers.

 

International experience in search and rescue operations

 

Foreign specialists shared their experience of similar search and rescue operations, sending detailed information on their conduct.

 

 

Mines rescue services PTY, South Africa.

 

        

Mannas Fourie – Chief Executive Officer of Mines rescue services.

 

They had a similar collapse relatively recently in 2020 at the Gamsberg mine. During the search for the dead, in order not to risk the rescuers chose the safest approach to the area of the victims - an additional tunnel was passed. During the search operations 1 victim was found.

 

   

 

In 2016 at the Lily Mine, three miners were in a container that went with the ground when it collapsed. Because the operation became too dangerous due to cracking and deteriorating ground conditions and would have required expensive emergency operation to access the casualty site, which the owners could not afford, the operation was halted. The three men who died have not been found.

 

 

 

Mannas Fourie also noted that no matter how advanced the technology is, the most effective thing to do is to use search dogs. Unmanned drones with metal detectors in most cases give ambiguous signals due to the presence of other metal objects in the same area.

 

    

 

FSUE "Militarized Mine Rescue Unit" of the Ministry of Emergency Situations of the Russian Federation, Russia.

 

    

Rudenko Vitaliy - First Deputy General Director for Operations and Technical Work.

 

Experience of the search operation at the flooding of the Mir Mine, 2017:

On August 4, 2017, an uncontrolled increase in water inflow into the underground mine workings occurred as a result of erosion of the host rock in the Mir open pit.

 

After several hours of work by mine rescue units, 142 people out of 151 were brought to the surface.

 

On August 26, 2017, after 528.55 hours of the search operation, due to the risk of a one-stage descent of water from the pit into the underground mine workings, the decision was made to stop mine rescue operations.

 

 

 

 

 

 

 

 

 

 

 

International Mines Rescue Body (IMRB), Canada.

 

              

 

Alex Gryska – Secretary-Treasurer of the International Mines Rescue Body (IMRB)

 

Proposal to improve the effectiveness of the search operation:

 

Conduct surveillance using a helicopter with infrared and thermal imaging capabilities, both day and night, to determine the presence of "heat signatures" that may indicate the location of the vehicle.

 

Apply seismic reflection to identify anomalies.

 

Use radar ground probing.

 

Perform soil compaction using polymer resin

 

Apply the method of vacuum excavation of rock mass.   

 

Consider the use of a water inductor similar to that used in sand mining.

 

Recommendations:

Given the high level of difficulty and the real risks to rescuers due to constant ground collapse, it is recommended that a comprehensive assessment of the situation be conducted on the need to continue the search and rescue operation.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

National Association of Rescue and Environmental Organizations, Russian Federation.

 

      

Korotkin Gennadiy – President of the Association, Chairman of the Association Council, Col. Gen.

 

Given the scale of the accident, the experience and professionalism of rescuers in such situations is crucial, and it is important to properly assess all risks and opportunities to optimize search and rescue operations.

 

Having carefully considered the information provided and given the complexity of conditions and weather factors, we believe that the best strategy may be to suspend the operation until more favorable weather conditions arrive. This will provide additional time to assess the situation and make more informed decisions.

 

At the current stage, based on the information provided, the rescuers face an increased risk associated with the continuation of search operations. The incident area is characterized by extremely unstable soil conditions, constant soil collapses from the slopes of the sinkhole, as well as possible voids under the surface, which increases the likelihood of new collapses and, therefore, seriously threatens the safety of rescuers.

 

I note that even in the warm season, conducting search operations does not exclude risks for rescuers. In this regard, consideration of the option of completing the operation at this stage seems more appropriate.

 

Understanding the seriousness and danger of the current situation, we sincerely empathize with the families of the rescuers who find themselves in this difficult situation. However, our top priority must remain the protection and safety of all those involved in the rescue operation.

In light of the current circumstances and given the unpredictability of the elements, we must recognize that risking the lives of additional people in the search operation is not justified. If there is a second collapse, it will require launching a new rescue operation, which will further increase the risks and result in additional losses. Therefore, it is our duty to weigh every decision to protect the rescuers working in the collapse zone.

We are confident that the decisions taken by the leadership of the operation will be based on a thorough and comprehensive assessment of all factors. We express our sincere hope for the successful and safe completion of this mission.

 

On our part, we will follow developments closely and learn valuable lessons from your experience.

 

We are also fully prepared to provide any necessary support. Our participation in this process is an expression of our deep respect for the efforts of Kazakhstani rescuers, our desire to assist in achieving the common goal of ensuring safety and efficiency of rescue operations.

 

Conclusion

The world wide experience of search and rescue operations shows that in cases of high risk, real threat to life and health of rescuers, it is necessary to make a difficult decision to suspend operations or to stop them completely.

 

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