Sludge 'kills' the regulating lake: The suspicious origin of the underground sewer!
(Baonghean) - Located 1.7m below the surface of the perimeter road, the underground sewer connecting the sludge settling pit to the Cua Nam regulating lake is the object that needs to be decoded to determine whether the incident of sludge overflowing into the regulating lake was due to an accident or intentional...
Search for blueprints
On the morning of October 22, 2019, returning to Cua Nam regulating lake, the state of the lake water pollution was clearly evident with schools of fish floating to the surface; around the lake shore, many fish died. At the mud discharge point, officers and workers of Nghe An Water Supply Joint Stock Company were operating mud suction equipment.
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The urban order officer of Cua Nam ward and Nghe An Newspaper reporter measured the mouth of the underground sewer; the mouth of the underground sewer connecting the sludge settling pit to Cua Nam regulating lake. Photo: Nhat Lan |
Together with the urban order officers of Cua Nam ward, we measured the sludge discharge culvert, determined that it was 1.5m long, nearly 1m wide; the discharge gate cross-section of the culvert was over 0.4m.2(0.9m long, 0.47m wide); the underground sewer is located 1.7m deep below the road surface surrounding the regulating lake. Estimated by the naked eye, the depth of the underground sewer (on the regulating lake side) is equivalent to or deeper than the sludge settling pits of Hung Vinh Water Plant.
Because the minutes prepared by the Working Group of the Environmental Police Department (with confirmation from the representative of the Hung Vinh Water Plant) determined that the wastewater from the sludge settling pit was reused by the plant, we asked a responsible officer who was working with the workers of Nghe An Water Supply Joint Stock Company to pump out the sludge: Why did Nghe An Water Supply Joint Stock Company build an underground sewer connecting the sludge settling pit to the regulating lake? This person replied: "That is in the design, I am not very clear..." After saying that, he went somewhere else.
Fish in the regulating lake suffocated and floated dead around the shore. Photo: Nhat Lan
Meeting some local people, they said that about ten years ago, this entire area was agricultural land of Dong Vinh Ward people (commonly known as Lang Vang lake) and not the place where the wastewater and sludge storage system of Hung Vinh Water Plant was located. At that time, the wastewater of the water plant flowed into the agricultural production area, negatively affecting the production activities of the people, and causing environmental pollution. Faced with this situation, the people made a petition, the authorities inspected and handled it, and then Hung Vinh Water Plant built this settling pit system.
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Nghe An Water Supply Joint Stock Company organized the pumping of sludge from the regulating lake back to the settling pit on October 22, 2019. Photo: Nhat Lan |
Verifying the information provided by the people, we were told by an environmental officer that in 2010, the press reported that Dong Vinh Water Plant discharged waste sludge into Lang Vang lake area, Dong Vinh ward, Vinh city, affecting the production activities of local people. Therefore, the Provincial People's Committee directed the relevant agencies to conduct an inspection. Through verification, the reason for this situation was that Hung Vinh Water Plant did not have a sludge collection and treatment system. From there, the Provincial People's Committee requested Nghe An Water Supply One Member Co., Ltd. (now Nghe An Water Supply Joint Stock Company) to urgently implement the Project of building a sludge collection and treatment pit; make a commitment to protect the environment... Around 2013, the new sludge settling pit system was put into use.
Taking sludge samples for testing. Photo: Nhat Lan
Where can I find the design of the sludge settling pit system and environmental protection commitments? This official said: According to regulations, the authorities where Nghe An Water Supply Joint Stock Company places the sludge settling pit system must have documents to carry out monitoring work... However, when asking the People's Committees of Cua Nam Ward and Dong Vinh Ward, the answer that Nghe An Newspaper reporters received was: They have never received the design documents of the sludge settling pit system of Hung Vinh Water Plant, or the environmental protection commitment documents of Nghe An Water Supply Joint Stock Company?
The project of the sludge collection pit for treatment of Hung Vinh Water Plant, belonging to Nghe An Water Supply Company Limited, was approved by the Provincial People's Committee to adjust the total investment in Decision 3681/QD.UBND-CNXD dated August 18, 2010. According to this decision, the total investment of the project is 5,704 million VND. Of which, the cost of site clearance (provisional) is 1,071 million VND; the construction cost is 3,983 million VND.
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The detailed planning drawing of the overall sludge settling area and the monitoring diagram do not show any underground sewer connecting to Cua Nam regulating lake. Photo: Nhat Lan |
Sewers of dubious origin!
It took a long time, but we finally got access to the files and documents of the Hung Vinh Water Plant's investment project to build a sludge collection and treatment pit, along with the environmental protection commitment of Nghe An Water Supply Company Limited.
In the Certificate of registration of environmental protection commitment No. 05/GXN-UBND dated November 26, 2011 issued by Vinh City People's Committee to Nghe An Water Supply Company Limited, the project owner "Investment in construction of a sludge collection and treatment pit of Hung Vinh Water Plant", Vinh City People's Committee has set out very specific requirements: The project owner is responsible for properly and fully implementing the environmental protection contents stated in the commitment, including: 100% of wastewater is collected, must ensure to meet QCVN 24:2009/BTNMT (column B) - National technical regulation on industrial wastewater before being discharged into the common drainage system of Dong Vinh ward;
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Environmental protection commitment of Nghe An Water Supply Company Limited when implementing the project of sludge collection and treatment pit of Hung Vinh Water Plant. Photo: Nhat Lan |
Regarding waste sludge: The Company signed a contract with Nghe An Province Urban Environment Company Limited to periodically collect and transport it to the city's construction waste disposal site in Hung Dong Commune or at places permitted by the competent authority (Vinh City People's Committee), achieving a rate of 100%; taking legal responsibility if violating the Law on Environmental Protection...
Also in the Certificate of registration of environmental protection commitment No. 05/GXN-UBND, Vinh City People's Committee also requires Nghe An Water Supply Company Limited to implement. In particular, it must report to Dong Vinh Ward People's Committee and Cua Nam Ward People's Committee on the content of the project's environmental protection commitment.
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An officer from the Environmental Police Department explains to a representative of Hung Vinh Water Plant the legal regulations on taking sludge samples for testing. Photo: Nhat Lan |
The most concerning thing is that in the detailed planning drawing of the overall layout of the sludge settling pit for the 60,000 m3/day treatment area, the drawing of the environmental monitoring location... apart from the sludge collection pits, the drainage system connected to the drainage ditch of Nguyen Tiem street, there is no trace of the underground sewer connecting the sludge settling pit to Cua Nam regulating lake.
This proves that the origin of the underground sewer connecting the sludge settling pit to the regulating lake is suspicious. And the opinion of many officials and people of Cua Nam and Dong Vinh wards that Nghe An Water Supply Joint Stock Company took advantage of the prolonged heavy rain to discharge sludge into Cua Nam regulating lake is well-founded!.
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The Vinh Citadel area is covered in ice and water (photo taken on October 16, 2019). Photo: Nhat Lan |
Working with Vinh Urban Infrastructure Management and Development Company (the unit managing the system of regulating lakes in Vinh City), Deputy Director Tran Van Cam confirmed that he witnessed the Working Group of the Environmental Police Department (Provincial Police) making a record of the incident on October 21, 2019. At that time, he heard a representative of Hung Vinh Water Plant present the wastewater and sludge treatment process of the plant. When he learned that the wastewater after settling was collected and reused by the plant, he was concerned about the purpose of the underground sewer. Mr. Cam said: "After this incident, we should consider plugging the underground sewer. In case the underground sewer still exists, Nghe An Water Supply Joint Stock Company must commit to only being allowed to drain treated water in the settling pits into the regulating lake...".
According to Mr. Tran Van Suu - urban order officer of Cua Nam Ward People's Committee, discharging large amounts of sludge into the regulating lake will have two risks. Firstly, it will cause environmental pollution. Secondly, the regulating lake has the function of draining water. When sludge overflows in large amounts, in addition to occupying a part of the lake's volume, it will cause blockage at the drainage gates, leading to slow drainage. The heavy rain on October 16th, the area of 4 blocks of Cua Nam Ward in Vinh Citadel had a deep and long-lasting flooding situation, which is very likely due to this cause.