Along the Gongyi section of Zhengzhou-Xi 'an high-speed railway, you can reach Wogou, Beisi Village, Huiguo Town, gongyi city, where there is a huge "fortress" with a volume of 3 1.647 cubic meters. Looking up from the edge of the "fortress", the dam made of hard stones is 10 meters high.
The villagers near Huiguo Town, especially those in Beiluo and Qingxi villages, know that this "fortress" only 3 kilometers away from Luo Yi River stores more than 50,000 tons of chromium slag. Since 1990, the "chromium slag fortress" has existed here for 20 years.
The chromium slag heap was not here originally, but was piled in the open air in the yard of a local chemical plant. Because it caused a lot of dissatisfaction, it was removed at 1990.
201012 Wu Jiwei, chief of the disposal department of gongyi city Environmental Protection Bureau and director of the hazardous waste radiation center, said: The chromium slag piled up in Huiguo Town is the chromium slag produced in the production process of the second chemical plant in Huiguo Town, Gongxian County, and is called "the second child" by the local people.
"Laoerhua" was established in April of 1976, mainly producing chromic anhydride. "At that time, the business was quite prosperous. It was the backbone enterprise of Huiguo Town and even the whole gongyi city, with a large tax source."
However, the process of producing chromic anhydride will produce a lot of chromium waste residue. "At that time, the awareness of environmental protection was weak, and the harm of chromium slag was not well understood. Untreated and piled up everywhere, the groundwater in villages such as Beiluo and Qingxi was polluted. When the rainy season comes, the chromium slag leaching solution enters the Luo Yi River with the rain, and the surface water is seriously polluted ... "
In the early years, the vegetables and grain grown by farmers who returned to Guo Town were sold to other places without eating them themselves. Sometimes the land is almost barren, the fish in the water are hard to survive, and some inexplicable diseases of the surrounding villagers are hard to find. The villagers blamed it on chromium slag pollution, and disputes between factories and groups continued.
1990 under pressure, "Laoerhua" expropriated 6 mu of land in Wogou, Nanbeisi Village, Huiguo Town, and built a chromium slag dump. Although the bottom of the garbage dump has hardened, a slag dam has been built and covered with a 50 cm thick lime-soil cushion, the new chromium slag produced by the factory is still threatening the surrounding environment.
1992, the "second child" was forced to shut down. Chromium slag is sealed in pits and cracks.
According to the investigation by the Provincial Environmental Protection Department, there are five chromium slag piles like Huiguo Town in the province, which are hiding in Sijianfang Township, hua county, Anyang, Dakuai Town, Fengquan District, Longting District, Kaifeng, Sanmenxia, yima city and Dawei Town, xinmi city, Zhengzhou.
The six chromium slag piles are all 520,000 tons, of which the smallest is in Xinxiang with 28,400 tons, and the largest is in yima city with 325,000 tons. The chromium slag of Yima accounts for 67% of the whole province. "Once these pollutants enter water or soil, they are difficult to remove and may affect generations."
What is chromium slag? What's the harm?
Shao Fengshou, director of the Solid Waste Management Center of Henan Provincial Environmental Protection Department, told reporters that chromium is a silvery hard metal, which is slightly lighter than iron and has trivalent and hexavalent compounds. All compounds containing chromium are toxic, among which hexavalent chromium is the most toxic. Chromium slag is an industrial waste produced in the process of producing metal chromium and chromium salt, and it is a kind of hazardous waste with strong toxicity.
Due to the specific needs of the production process, as long as chromium is not converted into products and fixed and becomes insoluble, these chromium will become ionic chromium, soluble in water, and soon become highly toxic hexavalent chromium.
"If soil and water are rich in hexavalent chromium, they are easily absorbed by organisms. If the chromium residue left over from history is not effectively disposed of, it is a very serious safety hazard to the entire ecosystem. " Shao Fengshou said.
1June18th, relevant personnel of Henan Institute of Occupational Disease Prevention and Control introduced that chromium poisoning refers to that the content of chromium in human blood and urine exceeds the normal standard. Workers engaged in chemical industry and electroplating are prone to chromium poisoning, and hexavalent chromium is easily absorbed and accumulated in the body.
A doctor engaged in toxicity research said that industrial exposure to chromium and its compounds is mainly dust and smoke produced by chromium ore and chromium smelting. Clinically, chromium and its compounds mainly infringe on skin and respiratory tract, leading to dermatitis, ulcer, rhinitis, perforation of nasal septum, pharyngitis and so on. Long-term exposure is also very harmful to the digestive system, and gastrointestinal ulcers will occur, and taste and smell will be reduced or even disappeared. "But there is no specific treatment for acute and chronic chromium poisoning in clinic, and it is generally treated according to the symptoms of metal poisoning. Chromium has carcinogenic effect, and the carcinogenic site of chromium is mainly lung, followed by liver and kidney. "
A researcher at the Occupational Health and Poisoning Control Institute of China Center for Disease Control and Prevention said: Hexavalent chromium is mainly a chronic poison to human beings. After it invades human body through digestive tract, respiratory tract, skin and mucous membrane, it mainly accumulates in liver, kidney and endocrine glands. After people and animals drink water containing hexavalent chromium, hexavalent chromium will be absorbed by cells of many tissues and organs in the body. The lethal dose for humans is 5 grams. But at the same time, the researcher also said: chromium is also an essential trace element for human body, and the normal range of chromium intake per day is 0.05 micrograms. Eye myopia and diabetes are related to chromium deficiency.
According to the information of the Ministry of Environmental Protection, the main heavy metal pollution in surface water in China is mercury, followed by cadmium, chromium and lead. At present, the cultivated land area polluted by heavy metals such as cadmium, arsenic, chromium and lead in China is nearly 20 million hectares, accounting for about 1/5 of the total cultivated land area. Heavy metal pollution reduces China's grain production by 10 million tons every year.
Zhao Qiguo, an academician of Chinese Academy of Sciences who has been dealing with soil all his life, said: "After years of production in metallurgy, chemical industry and other industries, pollutants have already penetrated into the soil. Some chemicals have infiltrated into the soil, and some still exist even after 30 years. Once these pollutants enter water or soil, they are difficult to remove and may affect generations. After the chemicals in the soil enter the food chain, they are still eaten by humans themselves. "
During the interview, the reporter learned that in 2005, the State Council issued a notice to the whole country, demanding that all historical chromium residues should be disposed of harmlessly by the end of the Eleventh Five-Year Plan, that is to say, the end of this year is the time limit for disposal. The phenomenon of extravasation still exists under continuous dressing.
So, why have these "poison castles" been threatening people's safety for decades?
Since 1950s, more than 70 sodium dichromate chemical enterprises, also known as chromate enterprises, have been established in China. Sodium dichromate is the mother product of chromate series products, which has a wide range of uses, good enterprise benefits, but serious pollution.
Han Chongting, Minister of Security of Yima Zhenxing Chemical Group Co., Ltd., is from Kaifeng. He has been a technician in the chromium salt industry for nearly 30 years. He attributed the formation of chromium slag heap to backward technology. However, there is a great demand for products containing chromium. "Stainless steel faucets, spoons, chrome-plated handlebars and bicycle rims, jewelry, tapes, watchbands and even coins all contain chromium. Ordinary metals can be rustproof after chromium plating, and low-priced metals are durable and beautiful after plating with a thin chromium film. "
Chromium salt enterprises mainly extract metal chromium and chromium compounds from chromite, and a large amount of chromium slag is produced in the production process. According to the data, due to the backward production technology in that year, the extraction rate of chromium salt was only 75%, and 2.5 tons or even 3 tons of highly toxic chromium slag was discharged per ton of chromium salt products. Most of these chromium residues are piled up around the factory in situ, and only a few of them are protected by damming and sealing.
In 1980s and 1990s, the international community generally recognized the harm of chromium slag. Our government began to pay attention to the treatment of chromium slag pollution, comprehensively rectified the chromium salt industry, and gradually shut down and transferred more than 40 chromium salt enterprises.
The enterprise closed down, but left a large number of "ownerless" chromium slag piles. More than 6 million tons of chromium residue were left in more than 20 cities including Shanghai, Tianjin, Suzhou, Jinzhou, Baotou, Wuhan, Qingdao, Hangzhou, Shenyang, Jiangmen, Changsha, Guangzhou, Shaoguan and Zhengzhou. Due to the limitation of technology and financial resources, these chromium residues were not treated harmlessly in that year, thus forming a "fortress" of chromium residues. 101On October 20th, the reporter saw a bigger "chromium slag fortress" in Lianggou, 4 kilometers away from Yima city, which was 4 times larger than that in Wogou, Huiguo Town. The chromium slag scattered under the dam showed dazzling yellow under the drizzle that day, and there was a striking danger sign on the outer wall at intervals.
Zhang Weidong, head of the pollution control department of yima city Environmental Protection Bureau, said that hundreds of thousands of tons of chromium slag have been sealed for 26 years, which is the "legacy" after the vigorous development of Yima Zhenxing Chemical Plant.
According to a document of the Ministry of Environmental Protection, almost all enterprises that produce chromium slag are built in densely populated areas, scenic spots and upstream water sources. Only a few enterprises have anti-leakage facilities, and most of them are simply stacked. After being washed away by rain, hexavalent chromium in chromium slag flows into nearby surface water or seeps into groundwater, causing serious pollution to surface water, groundwater and soil.
However, the chromium slag piles in Huaxian, Xinxiang and Kaifeng Long Ting in Quanfeng have no protective measures from beginning to end. Wulipu Village Landfill Site in Dawei Town, xinmi city is located in the slag field of low-lying tunnel reconstruction opposite the former Wulipu Chemical General Factory in Zhengzhou City. This 3000-square-meter chromium slag dump has no protective facilities at the bottom, but the surface is completely covered by construction waste and domestic waste from nearby enterprises and residents.
101October 12, the director of the hazardous waste radiation center of gongyi city Environmental Protection Bureau said with emotion: "Even if all these 50,000 tons of chromium slag (returned to Guozhen) are treated harmlessly, it is likely that it will take 40 years for the ecological water system and soil in this area to recover to the past ..."