Finding the cause of subsidence in the mineral capital of Nghe An

Tan Hoang Khang's Abnormalities

In late May, we were at Na Hieng village, Chau Hong commune. This is the village most severely damaged by the unusual subsidence, with most of the houses in the village cracked, dozens of “death holes” appeared and wells dried up. According to the locals, in recent days, the subsidence has become worse. Almost every day, at least one house has cracked, along with a series of “death holes” so deep that the bottom is invisible.

About 500m from the residential area of ​​Na Hieng village is the Thung Lun tin mine, owned by Tan Hoang Khang Joint Stock Company. At this mine, according to the reporter's records, some workers are still urgently pumping groundwater from underground tunnels and pouring it into the wastewater dump. Despite this, since May 11, the People's Committee of Quy Hop district has issued a notice requesting this enterprise and other organizations and individuals to temporarily stop pumping and exploiting groundwater.

Thung Lun mine is still pumping underground water out of the mine despite the fact that on May 11, the district People's Committee issued a document requesting a temporary halt. Photo taken on May 24. Photo: Tien Hung

In addition, there are also many vehicles and machines lying around. The pumps used are all high-capacity pumps. Not far away are 3 tunnels leading deep into the mountain, this is the area for tin mining. These tunnels are quite wide, enough for trucks to enter and exit.

According to the reporter's investigation, deep inside the mountain is a dense tunnel system, with a total length of kilometers. To exploit the tin ore seam, the mine owner must ensure that the inside is always dry and not flooded by underground water. Therefore, right in the middle of the mine area, they drilled a water well up to 260m deep. Then, workers used high-capacity pumps to pump water up and then discharge it outside through large pipes installed along the tunnel. According to the people, drilling hundreds of meters deep like that and continuously pumping water has caused the surrounding underground water source to be depleted, leading to subsidence.

Dwarf Valley Mine seen from above. Photo: Tien Hung

Also at this mine, a worker in charge of pumping water said that currently the pumps are pumping at a capacity of 200-300m per hour.³water from the mine. This person also said that it is unclear how much waste the company is licensed to discharge. Meanwhile, according to the approved environmental impact assessment, this mine is only allowed to pump water out of the mine at a flow rate of 5.6m³/hour. Thus, the water flow that this company was pumping at the time we were there was about 40 times higher than the regulation.

Failure to comply with district notice

According to Mr. Truong Van Hoa - Chairman of Chau Hong Commune People's Committee, the situation of groundwater depletion began to occur at the end of 2019. Initially, wells ran dry, then houses cracked and collapsed... Since then, Chau Hong Commune has had up to 30 reports on the unusual subsidence situation sent to superiors. However, up to now, many inspection teams have come but there is still no conclusion on the cause.

Meanwhile, the subsidence situation is getting more and more serious, not only affecting the lives but also threatening the lives of the people. Recently, people are even more upset when many "death holes" were filled by "someone" with excavators just 1 day after they appeared.

“The investigation team is coming back, so they should leave those holes behind to investigate the cause. Why do they have to quietly fill them up like that? Isn’t that erasing traces of the scene and evidence?”, a resident of Na Hieng village asked.

A "death hole" was filled in just 1 day. Photo: TH

Not only the people, but also in many reports of Chau Hong commune, the cause of this situation is due to mineral exploitation companies in the area. "People here have lived here for a long time and this situation has never happened before, when there were no mineral exploitation activities," said the Chairman of Chau Hong commune People's Committee.

Although he said he did not dare to name the culprit who caused the subsidence because he had to wait for the conclusion of the authorities, however, in the conversation with us, the Chairman of the People's Committee of Chau Hong commune also gave many details related to the Thung Lun tin mine of Tan Hoang Khang Joint Stock Company. According to Mr. Hoa, when this mine temporarily stopped pumping water from the mine, some of the people's wells that had previously dried up began to have water again. In addition, recently, Tan Hoang Khang Joint Stock Company also generously supported Chau Hong commune with more than 3 billion VND to build water pipes from streams to households whose wells had dried up. However, this pipe is only enough to provide water for a few dozen households.

Tin mining tunnel of Tan Hoang Khang Company. Photo: Tien Hung

According to the reporter's investigation, in recent days, Tan Hoang Khang Joint Stock Company has sent people to many households with cracked houses to discuss support. "The company came to support us with 200 million VND, but they put forward many conditions. One of the conditions was that we had to demolish the old house and rebuild a new one. How could that amount of money be enough to build a new house? Because they supported us with conditions, my family decided not to accept the money," said a resident of Na Hieng village who asked to remain anonymous. Previously, in early May, this person's fairly decent house had a "death hole" right in the middle of the living room. Since then, the whole family had to move to the porch to live because they were afraid. In addition, the house's walls were also covered with cracks, at risk of collapsing at any time. Meanwhile, the family's water well had dried up since the end of 2019.

“If they were not the culprits, why did they have to spend such a large amount of money to support the commune in building water pipes and supporting people with cracked houses?” another resident told a reporter from Nghe An Newspaper.

The North Central Geological Federation is drilling underground to investigate the cause of the subsidence. Photo: Tien Hung

A new "death hole" appeared under a resident's house on the morning of May 27. Photo: TH

Responding to the fact that the district had previously requested the temporary suspension of groundwater pumping but Thung Lun mine still did not comply, a leader of Quy Hop district said that on May 12, one day after the announcement, the district People's Committee coordinated with the Chau Hong Commune People's Committee to organize inspections and supervision at 8 mineral mining companies in this commune. The inspection results showed that only Tan Hoang Khang Joint Stock Company was still pumping groundwater to exploit tin ore. The district People's Committee then made a record, requesting this company to continue to temporarily suspend mining and pumping groundwater, and at the same time requested the Chau Hong Commune People's Committee to supervise the company's compliance.

Immediately after that, Tan Hoang Khang Joint Stock Company sent a dispatch to the People's Committee of Quy Hop district, in which it requested to create conditions for the company to continue production according to the approved design, including the solution of pumping water from the mine. "Because if we stop pumping water, our company will stop production and the entire mine system, equipment, machinery, and power system will be flooded and the damage to our company will be huge and to repair the flooded mine system will take a lot of time and cost a lot of money; at the same time, 250 officers and employees of Tan Hoang Khang Joint Stock Company and An Vinh Tin Smelting Factory will have to quit their jobs. These two units are the top annual contributors to the district's budget...", the company's dispatch stated. In addition, in this dispatch, Tan Hoang Khang Joint Stock Company also requested the People's Committee of Quy Hop district and the People's Committee of Chau Hong commune to coordinate with the company in supporting people to overcome the phenomenon of subsidence.

The People's Committee of Quy Hop district then issued a document, forwarding the company's proposal to the Department of Natural Resources and Environment for instructions. On May 18, the Department of Natural Resources and Environment responded in writing to this matter. In this document, the Department did not allow Tan Hoang Khang Joint Stock Company to continue pumping groundwater, but only commented that "while waiting for the agency to conclude the cause of the subsidence, enterprises can continue to exploit minerals, produce and do business normally according to regulations". However, Tan Hoang Khang Joint Stock Company still did not comply, and continued to openly pump water from the mine in a massive manner.

By the afternoon of May 27, after the request of the Chairman of the Provincial People's Committee Nguyen Duc Trung, the People's Committee of Quy Hop district had to issue a second notice requesting the immediate suspension of groundwater exploitation and use activities in Chau Hong commune. At the same time, Chau Hong commune was required to strengthen inspection and supervision of compliance by organizations and individuals pumping, exploiting and using groundwater in the area. Timely detect non-compliance, prepare records to handle violations according to the provisions of law.

On May 27, the People's Committee of Nghe An province sent a document on handling subsidence, cracks in land, constructions, houses, and dry wells in Chau Hong commune, Quy Hop district to the Department of Agriculture and Rural Development; Department of Natural Resources and Environment; and People's Committee of Quy Hop district.

The content of the document stated that the Provincial People's Committee issued Document No. 147/UBND-NN dated April 21, 2022 on subsidence, cracking of land, constructions, houses, and dry wells affecting production and daily life of people in Chau Hong commune, Quy Hop district; in which the Department of Agriculture and Rural Development was assigned to preside over and coordinate with the Department of Natural Resources and Environment and the Department of Construction to inspect and advise the Provincial People's Committee on handling measures before April 28, 2022.

However, up to now, the Department of Agriculture and Rural Development has not reported a final solution, which is not strictly implementing the direction of the Provincial People's Committee. To solve this problem, Chairman of the Provincial People's Committee Nguyen Duc Trung has the following opinion:

1. For the People's Committee of Quy Hop district:

- Direct organizations and individuals to immediately suspend groundwater exploitation and use activities of related projects in Chau Hong commune, Quy Hop district. Strengthen inspection, monitoring and have solutions to ensure absolute safety for the lives and properties of people in the affected areas.

2. For the Department of Agriculture and Rural Development:

- Criticize the Department of Agriculture and Rural Development for being slow in advising and reporting to the Provincial People's Committee on the handling plan; Request to review and clarify the responsibilities of relevant parties, and advise and report to the Provincial People's Committee before June 10, 2022.

- Preside and coordinate with the Department of Natural Resources and Environment, Quy Hop District People's Committee and relevant units to inspect the actual situation on the ground, advise the Provincial People's Committee on a plan to handle subsidence, land cracking, constructions, houses, and dry wells in Quy Hop district before May 31, 2022.

3. For the Department of Natural Resources and Environment:

- Request to inspect the compliance with environmental protection work of mineral exploitation enterprises in Quy Hop district.

- Closely and promptly coordinate with the Department of Agriculture and Rural Development and relevant agencies in handling subsidence, land cracks, constructions, houses, and dry wells in Quy Hop district.

A woman cried after witnessing her daughter's house sinking and cracking on the morning of May 27. Photo: TH

Been punished many times

According to the reporter's investigation, Tan Hoang Khang Joint Stock Company is a company that has been administratively fined many times. Most recently, on May 20, the People's Committee of Nghe An province issued a decision to impose a total fine of more than 276 million VND. Specifically, this company was fined 170 million VND for encroaching on 18,380m²agricultural land to build a wastewater treatment system, an operator's house, workers' housing, auxiliary works, roads, material storage area... in Thung Lun area, Chau Hong commune. Not only must the company restore the original state, it is also forced to pay back the illegal profits from administrative violations of 36.76 million VND.

Also in this decision, Tan Hoang Khang Joint Stock Company was fined 70 million VND for not properly implementing one of the contents of the decision approving the environmental impact assessment report. Specifically, in 2022, the company discharged wastewater pumped from the mine into the circulating settling tank system, then pumped wastewater from the circulating settling tank into the casket (discharged into the environment); meanwhile, according to the environmental impact assessment report, wastewater from the production process (from the processing plants) is collected, then mechanically settled and 100% circulated back to the processing system without discharging into the environment.

Cracks at Chau Hong Secondary School. Photo: Tien Hung

In addition, 1 month ago, in April, Tan Hoang Khang Joint Stock Company was fined 19 million VND by the People's Committee of Quy Hop district for not reporting or reporting late on occupational safety and hygiene as prescribed by law and not developing, promulgating or implementing plans, regulations and procedures to ensure occupational safety and hygiene at the workplace. Previously, in 2017, this company was fined 35 million VND because many indicators exceeded the permitted threshold....

Up to now, Chau Hong commune has had 299 dry wells. Photo: TH