What is the current state of soil pollution? Who is the “responsible person” for governance? What are the innovations in soil remediation technology? The reporter interviewed a number of industry, academia and research practitioners in the field of soil control, from the policy interpretation, technical response, industrial research and development and other aspects to inventory the current problems and opportunities in the field of soil pollution control in China.

Pollution status
Wide range, risk potential, can not be ignored
“A recent survey on soil pollution in the country shows that the quality of the soil environment in the country is not optimistic. The human factors such as industry, mining and agriculture are the main factors.” Luo Yongming, a researcher at the Nanjing Institute of Soil Science, Chinese Academy of Sciences, said that soil pollution includes heavy metal pollution and organic pollution. Pollution reduces or loses productivity and threatens the safety of agricultural, groundwater and human settlements.

“Because the early management of China’s industrial enterprises is not systematic, the operation records of most polluted sites have not been filed, making it difficult to trace the source of the site, the scope and extent of the pollution, and the analysis of the migration and transformation of pollutants.” Researcher, Nanjing Institute of Soil Science, Chinese Academy of Sciences Song Yu said.

Soil pollution is a huge threat to the “rice bag”, “vegetable basket” and “water tank”. In April 2014, the “National Soil Pollution Survey Bulletin” jointly issued by the Ministry of Environmental Protection and the Ministry of Land and Resources showed that the total over-standard rate of soil points in the country was 16.1%. From the perspective of pollution distribution, soil pollution in the south is heavier than in the north; soil pollution problems in some areas such as the Yangtze River Delta, the Pearl River Delta, and the old industrial bases in the Northeast are more prominent, and the soils in the southwest and south-central regions have a large range of heavy metals.

In the investigation, the reporter found that dangerous waste burial and industrial and mining development have also aggravated soil pollution in some areas. Since 2018, Taizhou, Yancheng, and Lianyungang in Jiangsu Province have repeatedly exposed environmental pollution problems such as solid waste smuggling, waste smuggling, and irregular wastewater treatment. Some enterprises bury buried pipes for 30 meters of sewage, some enterprises have not obtained the EIA procedures, and heavy metal pollutants are randomly stacked in the open air. According to statistics, from January to November 2018, there were 390 accused in Jiangsu Province due to the environment. The crime of pollution was sentenced to more than a maximum of 20 million yuan in fines.

Chen Mengxi, a researcher at the Chinese Academy of Sciences’ Hundred Talents Program, said that for Jiangsu in the Yangtze River Delta, soil pollution and treatment of chemical companies such as coking, electroplating, printing and dyeing, and pesticides are the main problems currently facing. With the development of urbanization, there are soil remediation needs after the relocation of some chemical companies.

Once the soil is contaminated, the consequences are very serious. Some industry experts said that soil pollution is characterized by concealment, latency and long-term. Through the layer conduction of the food chain, the health of animals and humans is deeply affected by soil pollution, and the process is very subtle and difficult to detect. And soil pollution has cumulative characteristics at the same time, pollutants are not easy to migrate, diffuse and dilute in the soil; even, soil pollution is irreversible, heavy metal pollution to the soil is basically an irreversible process, and many organic compounds are also polluted. It takes a long time to degrade. More importantly, the cost of soil pollution is high and the process of effectiveness is slow.
Repair technology
Path diversity, precise governance, system thinking
In terms of the treatment and remediation technology of contaminated soil, it is currently characterized by a diversified path in China.

“In the early days of the industry, most of the contaminated soil was treated by relatively simple technical methods such as cement kiln co-incineration or safe landfill. Nowadays, thermal desorption, soil leaching, in situ thermal desorption, in situ chemical oxidation, biological Advanced technologies such as restoration have become mainstream, and the overall level is synchronized with foreign countries. Li Shupeng, secretary general of the Soil and Groundwater Remediation Committee of China Environmental Protection Industry Association and deputy general manager of Beijing Construction Engineering Repair Co., said that the diversification and continuous improvement of repair technology is repairing. Engineering application innovation offers the possibility.

Earlier, the relevant departments had announced a number of technical equipment “tools” to repair the soil. In December 2017, the Ministry of Science and Technology and other five departments organized the Catalogue of Advanced Technical Equipment for Soil Pollution Prevention and Control, which published ectopic leaching and remediation technologies including contaminated soil, arsenic-contaminated soil sedge restoration technology, and ectopic indirect heat removal. Technical route, main indicators and trial range of 15 soil remediation technologies (equipment) with technical equipment.

Technologies such as bioremediation are a frontier area of ​​current researchers’ attention. “Bioremediation is a relatively good method of soil remediation, including the cultivation of hyperaccumulators, inoculation of microorganisms, etc. Hyperaccumulators such as mines can quickly transport cadmium to the aboveground parts, repair through winter and spring, summer and autumn rice. The way of recycling, after plant restoration, can reduce the heavy metal cadmium in the soil by 50%.” Luo Yongming said that some special plants can continue to accumulate heavy metal elements like “miners”. The current way in China is to incinerate these plants. Foreign countries can even collect and refine metals.

At present, two types of soil restoration are extremely urgent, one is the soil after the relocation of industrial and mining enterprises, and the other is farmland soil. “What the academic community is doing now is to strengthen the analysis of different industries, different regions and different types of soils, and provide accurate, green and sustainable restoration technologies.” Li Shupeng said that the soil remediation technology is diversified and the technical solutions are fine. It is the development direction of this field in the future.

Soil remediation should not only stay in the technology itself, but also involve extensions such as agricultural production and resource reuse. “In the past ten years, China has made great progress in soil management from theory to technical equipment, but there is still a gap with foreign pollution control technologies. Now we must not only manage for governance, but also consider system solutions to ensure food science production. On the basis of disposal, it is necessary to update the thinking.” Shen Renfang, director of the Nanjing Institute of Soil Science, Chinese Academy of Sciences said.
Responsible subject
Pollution control according to law, social participation, industry orientation
Who is the first person responsible for soil pollution control? The official promulgation of the Law of the People’s Republic of China on Soil Pollution Prevention and Control has made it possible for China’s soil pollution prevention and control to be law-abiding for the first time. It provides a rule of law guarantee for clarifying the main body of responsibility, carrying out soil pollution prevention and control work, and solidly promoting the “clean land war”.

The Law on the Prevention and Control of Soil Pollution stipulates that the person responsible for land pollution is the person responsible for land pollution and the owner of land use rights. Specifically, it includes key monitoring units for soil pollution, enterprises and institutions that demolish facilities, equipment or buildings, structures, key supervision units, tailings storage operations and management units, and local people’s governments.

“The domestic soil remediation industry has gone through three stages from economy and law to responsibility.” Gao Yanli, general manager of Beijing Construction Engineering Rehabilitation Co., believes that in the first phase, many soil remediation work is dominated by real estate development companies. Most of the development is driven by economic factors; in the second stage, soil pollution prevention and control strengthens the government and polluters’ responsibility for governance, and promotes the main body of soil pollution prevention and control, and the “regulation of pollution according to law” is the development direction; With the increasing awareness of public soil protection responsibility and the increase of central environmental protection inspectors, responsibility driving will become the main driving force for soil remediation.

At present, the field of soil remediation has attracted the active involvement of social capital. According to industry estimates, China’s soil pollution prevention and repair industry currently accounts for less than 1% of the total output value of environmental protection industry. However, in developed countries such as Europe, the United States and Japan, this proportion is as high as 30%, which means that the soil remediation market in the future will have potential for deep digging.

From the perspective of development mode, the soil remediation industry is mainly engaged in the contracting of traditional pollution control projects, and it is developing into a multi-model such as environmental steward, brownfield development and PPP. Insiders pointed out that according to the route set up by the “Ten Shi”, the deterioration of soil pollution in China will be effectively controlled in 2020, and then enter a benign development stage. In the process of soil pollution prevention and control work, the door of the soil remediation market will continue to open to social capital, and it is expected to open up a blue ocean space for the development of the industry.

The capital investment in soil remediation is huge, and it requires tens of millions or even billions of capital investment. At present, the state funds are mainly used to initiate the management and restoration of the remaining soil, and the expected capital investment will be much larger than the national start-up funds. Some experts suggest that the national and local soil remediation fund system be established as soon as possible, or that the leading enterprises should be reinforced by investing and integrating, and the technology-led type will be transferred to capital operation to ensure the sustainable development of China’s soil remediation industry.