Jinhekou City, Jilin Province, gold deposits, gold, land, land, green, green

First, the basic situation
(1) Basic profile of Meihekou City
Meihekou City is located in the southeast of Jilin Province, in the transition zone from Changbai Mountain to Songliao Plain. It is 97 kilometers long from north to south, 35 kilometers wide from east to west, and covers an area of ​​2174.6 square kilometers. It has 32 township streets in the city. In 1999, it had a population of 610.395. The total output value of the mining industry is 340 million yuan, and the number of employees is 22,198.
Meihekoushi is one of the northeast region an important hub of railway transportation to evacuate, national, provincial and county roads criss-crossing network of railway, highway transportation network provides good conditions for the Meihekoushi economic development.
(B) Meihekoushi sand gold ore basic overview
The Meihekou City gold deposit began preparations in the second half of 1987, and the first phase of the project was completed in November 1988. Trial production was carried out in April 1989. The annual output of gold is about 2000.
Meihekou City Sand Gold Mine is located in Shuitou Town and Zhonghe Town. The ore body is 12.1 kilometers long and covers an area of ​​4,500 acres. The average width is about 245 meters, the widest part is 450 meters, and the narrowest part is 30 meters. The reserves of gold deposits are 3,609.3 kg, the amount of ore is 16.08 million cubic meters, the average buried depth is 7.03 meters, and the average grade of mixed sand is 0.224 g/m3.
(3) Basic situation of gold mining and rehabilitation
In order to develop and utilize this valuable resource, four 100-litre gold mining vessels were initially designed. A medium-sized enterprise with an annual output of 5,889 gold. However, considering that more than 90% of the ore bodies are covered by high-quality paddy fields of 5,000 yuan per mu, there are more than 3,000 agricultural populations living on this land. Their ancestors lived on land for a long time, and the gold mining operations were “destroyed” by gold mining vessels. Whether the farmland and the gold-collecting land can be restored to the pre-harvest level has become the most concerned issue for the relevant departments, gold mine leaders and local farmers. For the sake of stability, the project is divided into two phases. The first phase of the project will only build two 100-litre gold-mining vessels. After the success of Futian, the second phase of construction will be carried out.
The two gold mining vessels will temporarily occupy and “destroy” the farmland by about 300 mu per year. If no effective measures are taken to rehabilitate the land, 4,500 mu of land that cannot be cultivated due to “destruction” after the end of gold mining will be abandoned. More than 3,000 peasants have lost the land they depend on, and will produce 4.5 million jin of rice per year, which will cause irreparable damage to farmers' vital interests and agricultural production. Therefore, the quality of the work of Futian is the premise and basis for the survival and development of the sand gold mine. Since the day of its birth, the city’s gold-gold mine has attached great importance to the work of stripping the land, and put it on the agenda, taking practical measures to pay attention to the work of reclamation, and testing the rice on the land of Futian to obtain a good harvest. Futian has been highly praised and commended by the Ministry of Geology and Mineral Resources, the State Land Administration and the National Gold Bureau.
From the construction of mines in 1988 to the present, at the beginning of each year, the Municipal Land and Minerals Bureau, the Waterway Town Government and the Sand Gold Mine signed the reinstatement agreement of the year (Annex 1 of the 2000 Reclamation Agreement). By the end of 1999, the accumulated land area was 3005 mu, and the land was returned to 2,635 mu. There were still 370 mu of land reclamation. It was re-examined before October 1 this year and returned to farmers.
In order to continuously improve and improve the work of Futian and create a new way to mine gold and summer fields, the work of Futian is reported as follows:
Second, do a good job in the specific work of rehabilitation
(1) The leaders attach importance to putting the work of divesting Futian on the important agenda [next]
1 The leadership team unified understanding and do a concerted effort. Because the use of gold mining vessels for gold mining is the first time in Meihekou City, it is unprecedented, especially in high-quality farmland, gold mining has never been experienced by leaders and employees at all levels of the gold mine. Therefore, at the beginning, the leaders and the masses only considered how to produce gold, how to complete the production task, and did not pay much attention to the work of stripping the land. The necessity of the importance of the work of Futian is also inconsistent in understanding. In response to this phenomenon, the leadership team of the mine held several special meetings and learned the "Mineral Resources Law", "Land Law", environmental protection and reclamation regulations. Let us realize that cherishing the land and protecting resources is a basic national policy of our country. First of all, to unify the understanding of the members of the leadership team, through repeated learning and discussion, it is clear that the work of Futian is the condition for the survival of enterprises. If there is no way to do a good job in Futian, there will be no way out. After the team's understanding was unified, it repeatedly promoted the important significance of the work of Futian to the staff and raised the awareness of the employees. At the same time, the production management department formulates the process plan for stripping and reclaiming the land according to the design plan and the geological conditions of different sections, and often studies and solves the specific problems that arise in the actual work. Therefore, the whole mine has formed the top priority. Good understanding of Futian. Therefore, in the daily life, we can make rational use of land, plan for land occupation, plan for reclamation, and incorporate the work of stripping and reclamation into the unified planning of production and construction of the team. Therefore, we must do a good job of stripping Futian to become the main artery of the whole mine.
2. Guarantee from the organization to the facility.
In order to do a good job of stripping the land, we have a full-time land manager in the Production Technology Section, which is responsible for handling the land occupation procedures, coordinating the specific issues of the land occupation process, and inspecting and guiding the construction site. The Ministry of Mines has set up a production team consisting of 19 people directly from the Futian production team. Two engineers were selected to serve as the team leader for the construction work. They were equipped with 6 bulldozers, purchased ripper, Wuhua plow, and garden hoe. In the spring, rural manpower and equipment are also temporarily employed for leveling operations to ensure that the land is returned to the plan.
3 Strengthening on-site guidance and management of Futian
The engineering and technical personnel, on-site construction workers, production dispatchers and mine-level leaders of the Production Technology Department often divested the work site of Futian, supervised and instructed according to the design and construction, assisted in solving the specific problems that occurred temporarily, and often requested the municipal land. The comrades of the Bureau of Mines and the leaders of the village and township governments and local farmers went to the scene to guide and inspect our work in Futian. We regard the stripping work as a prerequisite for the normal production of gold mining vessels. Unremitting work.
(2) Seriously study the experience of the field and formulate the plan for the stripping of the mine
In order to effectively carry out the work of stripping Futian, we have sent mine-level leaders and engineering technicians twice to study their experiences in the Ankang Gold Mine and Hengshui Gold Mine in Shaanxi Province. After returning, I carefully analyzed the different geological conditions of the two mines and the impact of the climate and geological conditions of the two regions on the growth of crops to find out the differences and commonalities. Through analysis and comparison, we have digested and absorbed the local experience, and practically formulated our stripping and rehabilitative plan and organized it in the production process. We are not only eager to learn from the field experience, but also do not have to work hard in the field to find out that it is suitable for local practice. The situation is used to guide our work in stripping Futian.
Our stripping of the Futian process is actually simple and easy. The bulldozer is used for layering and stripping. After gold mining, the bulldozer is used to backfill and level the soil. The five-bow plough is used to turn the ground. The method of using the garden to loosen the soil is to determine the stripping depth according to the geological conditions of different sections. The farming layer is about 500-600 mm. The mining area is pushed out, and then the clay is pushed out, and the soil stripped in layers is stacked separately. When the gold mining operation is finished, firstly, the tailings are leveled, the clay is backfilled in turn, then the topsoil is backfilled, and then the whole leveling operation is carried out, and finally the five-bow plow is used to loosen. Fill the plate once and you will reach the level of cultivation.
(3) In order to test the effect of Futian, a small-scale experimental field was built.
After the restoration of the land, the surface of the land seems to be flat, but if the land that has been restored by 6-7 meters is able to grow good crops, can it reduce production and reduce the output? This problem is everyone’s concern. In order to test the effect of Futian through practice, in the spring of 1990, we selected a 4  8 mu of land with poor soil quality after the restoration of the land (the foundation pit for the shipbuilding). When the crops grew very well, the harvest in autumn was 755 kg per mu. The yield of this mu was nearly 200 kg lower than the average yield per mu. There are several reasons for the reduction: [next]
1  inserted half a month later. The normal transplanting should be completed at the end of May. The local farmers have a saying that they are not inserted in June, and the experimental field was transplanted on June 20, which affected the production time.
2 seedlings are purchased from each household with the remaining weak seedlings, slowing the seedlings to return to the slower.
3 Originally two-thirds were dry fields, and after the restoration of the fields, the paddy fields were changed.
4 Because of the late evening, in order to promote, the fertilization was slightly larger, and some lacked experience. In the autumn, the water was released a few days later, and the rice blast was significantly reduced.
Without the above four factors, the land planted after the restoration of rice in Putian can be close to or reach the level of per capita harvesting.
(4) In order to grasp the nutrient content of the soil structure and crops after the restoration of the field, and then analyze the impact of the land on the crop growth after the restoration of the field, we sampled the soil after the original soil and the land after the restoration, and requested the Gongzhuling Soil Testing Center. Laboratory analysis. The analysis results show that there is no significant difference between the soil content after the restoration of the field and the soil composition before gold mining. The conclusion is: “The land after the restoration of the land can be planted with rice” (attached to the laboratory report annexes 3 and 4). In the spring of 1991, we In addition, the Tonghua Agricultural Science Research Institute conducted a rice planting comparison test at the production site. The conclusion of the test is that “after the digging at a depth of 5-7 meters, the soil and soil of the restored soil are the same, and because of the local soil thickness, the nutrient content has little effect. The result of the digging makes the permeability of the whole soil layer more than the original. Good soil, (the lower layer of the original soil is basically a loess layer) is conducive to rice growth and root activity, and has factors of increasing yield.
After the land reclamation, the land farmers planted rice according to the conventional habit cultivation method, which generally grew well and obtained a good harvest of an average yield of more than 1,000 kilograms. The peasant said: "I didn't expect the land after Futian to be so strong." This shows that the land after Futian has increased the natural fertility.
Third, the effect of the restoration
(1) Eliminate doubts, reduce land occupation resistance, and improve economic efficiency of enterprises.
Due to the success of gold mining and restoration, the farmland and farmers have not only reduced production but also increased production. It has been proved that the land after gold mining can restore the original land. Agricultural production is not affected, and the interests of farmers are not lost, thus eliminating the harassment of farmers and the doubts of leaders and management departments at all levels. The gold mines reoccupied the land, the farmers did not worry, and reduced the resistance from all aspects. As long as the farmers were paid a reasonable land compensation fee, the farmers originally allowed the gold mine to occupy the land, and the waterway town government wrote to the provincial environmental protection bureau. It is written that “the production practice in the past two years has proved that it not only does not affect the growth of crops, but also promotes the growth of rice and obtains a good harvest.”
Since the land after the restoration of the land is not reduced, the land compensation fee paid to the farmers is reduced to 50% compared with the period of construction. If the annual land occupation is 300 mu, the annual compensation fee can be reduced by 22 million yuan, reducing production. Cost, due to the resumption of successful land and mineral management departments, so as to reduce the burden on enterprises and improve economic efficiency.
(2) The land after Futian is more arable. The soil is relatively loose, does not seep, does not leak, does not return sand, and has good gas permeability for crop growth. The roots of rice grown in the original soil are dark brown, while the roots of rice grown in the soil after the restoration are white. According to Yan Guangbin, a researcher of the Deputy Director of the Institute of Agricultural Research, the rice roots are white, indicating that the roots are best developed. This phenomenon occurs only when the permeability of the soil is good.
(3) After the gold mining and land reclamation, the effective cultivated land area has been increased to facilitate unified planning.
Before the gold mining, the land was uneven, and the local land could not be cultivated. There were also small plots of land mixed with water and dry fields. The water supply system of the paddy fields was not reasonable. After the gold mining, large-scale flattening has turned the past ridiculous land and dry fields into large-scale paddy fields, increasing the area of ​​cultivated land, and can be based on people's subjective will. Re-arrange the water supply channels and refurbish the pool to facilitate standardized management.
(4) The land after the restoration of the land has played a deep-turning role, and the deep-seated nitrogen, phosphorus and potassium are easily absorbed by the plants. The active ingredients increase the fertility of the land, reduce the amount of fertilizer applied, and reduce the cost of agricultural production. By deep turning, pests and diseases can be reduced, which is beneficial to crop growth.
After more than ten years of production practice, under the leadership of governments at all levels and under the care and support of various departments such as land and minerals, we have achieved initial success in the work of Futian, but we are in the process of Production management is still not perfect, and there is still no experience. In addition to constantly unswervingly consolidating the achievements, the future will be open-minded, learn from each other, make the work of collecting gold and reclaiming land better, protect mineral resources, protect cultivated land, and protect the environment. To benefit the people and create a blue sky for future generations.

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