Uranium mine geological radiation protection and environmental protection regulations

1 Subject content and scope of application

This standard specifies the geological radiation protection and environmental protection principles, dose limit standards, protection requirements and management measures for uranium mines.

This standard applies to the production, scientific research, and education departments of uranium geology. Other geological departments that contain natural radioactive materials may also refer to implementation. 

2 Reference standard

GB 4792 Basic Standards for Radiation Hygiene Protection

GB 8703 radiation protection regulations

GB 9133 Classification Standard for Radioactive Waste

General provisions for GB 11215 nuclear radiation environmental quality assessment

GB 11806 Regulations for the Safe Transport of Radioactive Material

3 terms

3.1 Uranium geological radiation staff: In the uranium mine geological work, its professional posts are accompanied by radiation exposure workers.

3.2 Uranium mine exploration: The uranium geology unit conducts underground operations for the exploration of uranium geological resources. 

3.3 By-product ore, uranium ore produced in the process of uranium ore exploration. 

3.4 Uranium geological waste residue: General term for by-product ore and other solid waste generated during production processes such as uranium geology

3.5 æ°¡Precipitation rate: The amount of sputum released from the unit area interface in unit time interval, the unit is Bq/m ² ·s.

3.6 Equilibrium Equivalent Concentration (ECRn): Any mixture of radon and its radioactive imbalance in the air

In the case of coexistence of activity, in order to facilitate the convenience of monitoring, an amount used to measure the concentration of strontium in place of the alpha potential concentration of the scorpion body mixture is measured. The ECRn of the radioactive unbalanced scorpion body mixture in air is the erbium concentration at which the scorpion body mixture is in a radioactive equilibrium, at which point the two scorpion body mixtures have the same total alpha potential concentration. The unit is J/m ³ or Bq/m ³ . 

3.7 Balance factor of alpha potential (F): ratio of equilibrium equivalent enthalpy concentration (ECRn) to actual radioactive concentration (CRn) of krypton in air: F = ECRnCRn (1)

3.8 scorpion body: short-lived decay product of 氡-222. These include 钋-218 (RaA), lead- 214 (RaB), -214 (RaC), and 钋-214 (RaC'). 

3.9 Exposure of radon progeny: time integral of radon progeny in air concentration. The unit of exposure is different depending on the unit used for the concentration of the scorpion. When the concentration of the radon progeny is in units of Bq/m ³ or J/m ³ , the exposure amount is represented by Bq·h/m ³ or J·h/m ³ , respectively. 

3.10 Sub-body: short-lived decay product of 氡-220. These include 钋-216 (ThA), lead-212 (ThB), -212 (ThC), and 钋-212 (ThC'). 

3.11 alpha potential: The alpha potential of an atom in a decay chain or a decay chain is the total alpha energy emitted by the atom as it decays into lead-210 (RaD) or lead-208, respectively, in units of J.

3.12 Alpha potential in air: The sum of the alpha potential of all helium or short-lived decay product atoms present in air per unit volume, in J/m ³ . 3.13 Long-lived alpha radiator concentration in air: the sum of long-lived alpha radiators per unit volume of air, in units of Bq/m ³ . It is usually obtained by analyzing the total alpha concentration in a unit volume after the decay of the short-lived daughter. 

3.14 Working Level (WL): A unit commonly used in uranium mines and geology to indicate the concentration of radon progenitor alpha potential. When the total alpha potential of the scorpion or scorpion in 1 L of air (regardless of the composition of various short-lived daughters) is 1.3 × 10 ⁵ Mev, its alpha potential concentration is called 1 WL. When expressed in SI units, 1WL is equivalent to 2.08 × 10 ^-5 J/m ³ .

4 General provisions

4.1 Radiation protection must comply with the three principles of “practical legitimacy, radiation protection optimization, and personal dose limits”; environmental protection must implement environmental regulations and standards promulgated by the state, and adhere to the principle of “who pollutes who is governed”. 

4.2 Radiation protection and “three wastes” treatment facilities for new construction, expansion and reconstruction projects must be designed, constructed, and put into operation simultaneously with the main project. 

4.3 The uranium ore geological research institute, the uranium ore processing room and the excavation tunnel with a length of more than 500m in the main lane shall be submitted to the “Environmental Impact Assessment Report” in accordance with relevant regulations before construction or expansion. 

4.4 All units engaged in geological radiation work of uranium mines shall set up protective agencies or dispatch special (part-time) protective technical personnel to be responsible for radiation protection work, and report radiation protection monitoring data in accordance with relevant regulations. 

4.5 For uranium geological radiation workers, education on safety and radiation protection knowledge should be strengthened, and assessments should be carried out on a regular basis to consciously abide by the various systems and regulations for radiation protection. The newly-employed personnel must undergo training and assessment by the radiation protection department, and they can engage in radiation work after passing the qualification.

4.6 The uranium geological radiation work unit shall, in accordance with the requirements of these regulations, and the specific conditions of the unit, formulate the management measures for radiation protection and environmental protection of the unit, radiation monitoring and quality assurance program and post responsibility system. 

5 dose limit

5.1 The uranium geological radiation workers and the public are subject to the control of the source and practice of radiation exposure annual dose equivalent limit see GB 8703. 

5.2 Pregnant women, breastfeeding women and those under the age of 18 (including students and apprentices who are required to receive radiation) may not engage in uranium geology underground operations and may not receive special pre-planned exposures. Women of childbearing age who are engaged in radiation work should control the dose evenly on a monthly basis. Except for a uniform monthly dose, the annual effective dose equivalent should be limited to less than 15 mSv. 

5.3 The limits for the intake of common nuclides in uranium geology are shown in Appendix A (Supplementary). For the annual intake limit (ALI) of other nuclides, see GB 8703. 

5.4 For the workplaces where the short-lived daughters of 氡-222 and 氡-220 are the main hazards, their short-lived daughters have an annual intake limit of 0.02 J and 0.06 J, respectively. 

5.5 Radiation workers shall meet both the requirements for formula (2) and the annual dose equivalent limits for the relevant organ or tissue, both when exposed to external exposure and by multiple radionuclides.

(HE) outside 50+ΣjIZ (ALI) Z≤1 (2)

Where: (H _E ) annual effective dose equivalent produced by _{external and} external irradiation, mSv;

I _Z - annual intake of radionuclide j, Bq/a;

(ALI) _Z -radioactive nuclear factor j annual intake limit, Bq/a;

In the uranium exploration underground operation site, if the dose contribution of the uranium long-lived radionuclide is negligible, then the formula (2) can be simplified to the formula (3):

(H _{E) outside the} + (H _{E) sub} ≤50 (3) 

Formula: (H _E) of radon daughters in _{the sub-workers} have effective dose equivalent, mSv; other symbols as in equation (2). 

5.6 When the concentration of α potential of the scorpion body is more than 4.16×10 ^-5 J/m ³ (2 WL), the site should stop working in principle, the concentration is (2.08~4.16)×10 ^-5 J/m ³ (1~2WL) ) Take effective protective measures.

5.7 Radiation workers shall not exceed 100 mSv (10 rem) in one event and not more than 250 mSv (25 rem) in one lifetime and shall be subject to the annual dose equivalent limit of the organ or tissue, due to the effective dose equivalent of the special radiation planned in advance. . Specially planned special exposures must be approved by the unit or the superior radiation protection department and carefully planned.

6 Derived concentration of radionuclide

6.1 The air-derived concentration of common nuclides in uranium geology and the derived ingestion concentration are detailed in Appendix A (Supplementary). See the GB 8703 for the air derived concentrations of other nuclide. 

6.2 The derived concentration is only a reference value given for the convenience of design, management and monitoring. Based on the annual intake limit, the derived concentration may be increased or decreased according to the actual intake. 

6.3 Exposure to only 氡-222, 氡-220 gas itself without its child body mixture, or the amount of short-lived daughters inhaled, is negligible (such as masks made with high-efficiency filter materials), 氡The air derivation concentration of -222 and 氡-220 can be increased by 100 times. 

7 Control level of radioactive surface pollution

7.1 The control level of radioactive surface contamination shall be implemented in accordance with GB 8703. 

7.2 Radiation in the indoor walls adjacent to the workplace, the level of pollution of equipment and the ground shall not exceed one tenth of the level of surface pollution control in the workplace. 

8 Main protective requirements for the workplace

8.1 Classification of radiation workplaces and classification of open radioactive workplaces is given in GB 4792. 

8.2 Class A open radiation workplaces shall not be located in urban areas. When necessary, it needs to be reviewed and approved by the radiation protection and environmental protection departments. 

8.3 Newly built radiation workplaces should choose locations with low population density and good dilution and diffusion conditions of radioactive waste gas, and should be concentrated in one area as much as possible, and set in the residential area or other workplaces according to the local minimum frequency wind direction. side. 

8.4 In the newly created workplace, at least three candidate sites should be selected for comprehensive evaluation and selection. 

8.5 Radiation workplaces should have a certain protective distance from residential areas and drinking water sources, as shown in Table 1. The area within this distance is delineated as a planning restricted area. Radioactive materials in the area should be monitored regularly. 

8.6 Where the workplace where radioactive dust or aerosol is generated, the floor, walls and canopy shall be decorated with building materials that are not easily stained, and strive to be smooth; the indoor structure shall be simple, reduce the dust surface and facilitate cleaning. Mineral analysis rooms, broken samples, etc. should be paved with cement floors, and ground drains and sewage treatment tanks. For workplaces with strong acid and alkali, an acid-resistant and alkali-resistant workbench should be installed. 

8.7 Uranium ore samples should not be stacked in places where people frequently enter and exit. 

8.8 The height of the exhaust pipe of the uranium ore processing room and the smelting chamber must exceed the highest ridge of the surrounding (50m range). 

Table 1 Planning limit distance of uranium geology and radioactive workplace

9 dustproof and falling

9.1 In underground working places, comprehensive measures such as “enhanced ventilation, adhere to wet operation, close dust source, personal protection, strengthen protection facility management and regular inspection” must be adopted to reduce the concentration of harmful substances in the air below the national standard.

9.2 Where there is a ground working place where radioactive dust and harmful gases are generated, ventilation means shall be provided. The ventilation system shall prevent backflow of pollutants. The dust concentration of the air inlet shall not exceed 0.1 mg/m ³ and the concentration of antimony shall not exceed 150 Bq/m ³ . 

9.3 Downhole ventilation requirements:

9.3.1 For all overpass and inclined wells exceeding 20m, shafts or shallow wells exceeding 10m, and patios exceeding 5m, mechanical ventilation shall be used. Pressing ventilation should be adopted for the working face. The end of the air duct should not exceed 10m from the working face. When the roadway or roadway is turned into a tunnel, the depth should exceed 5m, and special ventilation should be provided. 

9.3.2 When entering the tunnel, ventilation must be carried out to reduce the equilibrium equivalent enthalpy concentration in the pit to about 2.08×10 ^-5 J/m ³ and the ventilation time should not be less than 15 min. There is no time to stop the wind in the pit. 

9.3.3 The determination of the amount of ventilation should first satisfy the air volume required to reduce the enthalpy and its daughters in the roadway below the restricted concentration.

9.3.4 The exhaust air outlet of the tunnel shall be located on the windward side of the minimum wind frequency of the air inlet. The air outlet and the air inlet shall have a certain distance, so that the dust concentration of the main air inlet of the tunnel is not more than 0.1mg/m ³ and the radon concentration is not more than 150Bq/ m ³ ; The dust concentration of the working surface is not more than 2 mg/m ³ . 

9.4 Downhole sealing and lowering measures:

9.4.1 Completed roadways should be closed in time. The closure should be tight and firm. If you need to enter the closed tunnel due to work, you must wear the anti-virus respirator and personal dosimeter with the consent of the protection department, and re-sealing it immediately afterwards. 

9.4.2 The seepage and crack development areas of the main roadway shall be sprayed with anti-mite cover to reduce the precipitation of plutonium. And minimize the residence time of the ore in the unclosed roadway. 

9.4.3 The drainage ditch shall be cleaned frequently to keep the water flowing smoothly. For the downhole water with high radon concentration, special pipes shall be provided to discharge the water directly into the waste water treatment facilities outside the pit. 

9.4.4 Along the vein tunnel must be designed outside the vein. By-product ore and waste rock must be stacked separately during construction. 

10 Uranium mine geological waste discharge and treatment

10.1 Uranium geological wastes with specific activity greater than 7.4×10 ⁴ Bq/kg should be backfilled as much as possible. The waste slag with specific activity less than 7.4×10 ⁴ Bq/kg should be stored stably or shallowly buried on the ground, and then the loess should cover the vegetation; the buried place should be selected from the living area of ​​the residential area and the water source, and it is not easy to be washed by rainwater and groundwater. Undeveloped place. 

10.2 When using the heap leaching method to treat by-product ore, measures should be taken to prevent secondary pollution to the environment. The waste generated by heap leaching should be disposed of at 10.1. 

10.3 Flammable pollutants such as labor insurance products, paper, wood, etc. that cannot be recycled shall be incinerated in places where the protection requirements are met, and the remaining ash shall be stored together with other solid wastes. 

10.4 The waste liquid in the uranium analysis room should be poured into the special waste liquid pool, and it should be disposed of regularly and prohibited from being discharged. A special tailings pool must be set up between the samples and processed regularly. 10.5 The wastewater discharged during the drilling process must be set up for treatment and should not be discharged directly into farmland or economic waters. After the drilling is completed, proper and reliable sealing measures must be taken. 

10.6 When wastewater is discharged into rivers, the wastewater discharge and discharge concentration should be controlled according to the river dilution capacity to ensure that under the most unfavorable conditions, the concentration of radionuclides at the nearest water intake point downstream of the discharge port is not greater than the derived feed concentration. 

10.7 The additional concentration of airborne radionuclides in the public living environment caused by exhaust emissions shall not exceed 0.6 times the annual average of the DAC _public . When exhaust emissions make the annual intake of key groups more than 1/3 of the corresponding annual intake of the public, in addition to limiting the concentration of emissions, the total emissions must also be limited. 10.8 The discharge and treatment of non-radioactive nuclide are in accordance with relevant national regulations. 

11 Decommissioning treatment in radiation workplaces

11.1 If the radionuclide content in the discharged water of the completed tunnel exceeds the prescribed standard, the water blocking wall shall be constructed at the tunnel entrance. 

11.2 Radiation workplaces must be disposed of before disposal. After treatment, the waste slag yard should be set with strong and obvious marks to prevent damage. The surface enthalpy precipitation rate should be no more than 0.74Bq/m ² ·s. 

11.3 When the radiation workplace is decommissioned, comprehensive monitoring shall be carried out and the radiation environmental quality assessment shall be made. 

11.4 Radioactive waste should not be used as building materials and should not be used on radioactive waste dumps. 

12 Radioactive source management and transport of radioactive material

12.1 Sealed radioactive sources with a radioactivity greater than 5×10 ⁴ Bq must be uniformly registered and managed by the department in charge of the geological unit, designated to be kept by a special person, strictly handle the procedures for diversion and handover, and regularly inspect and check. Ordering, distribution and scrapping of radioactive sources shall be reported to the security and security department for record. Scrapped radioactive sources must be disposed of in accordance with relevant regulations. 

12.2 The solid radium source shall be placed in a lead can and placed in a tightly packed container with a dose equivalent rate of no more than 2.5 μSv/h at any point 5 cm from the surface of the container and placed in a safe and reliable source bank. 

12.3 The radium source must be checked regularly for leaks. 

12.4 To transport solid radium sources, the source must be placed in a container that meets the protective requirements. It is strictly forbidden to take public transport with you. 

12.5 If the radium source is lost or damaged, take immediate measures to prevent the accident from expanding and avoid contamination of the body and wounds. And report to the supervisor and supervision department in a timely manner. Refer to GB 8703 for the format of radioactive source loss accident classification and accident report. 

12.6 When using a radium standard source, it is necessary to minimize contact time and increase the operating distance, and to take shielding measures. 

12.7 For the transportation of ore and mineral samples, measures must be taken to prevent leakage and dust. Vehicles carrying ore must be carefully cleaned and decontaminated after use. 

12.8 railway transport performed in GB 11806. 

13 Personal protection and sanitation

13.1 In the radioactive dust working places such as the tunnel entrance and the broken sample room of the uranium mine exploration, it is necessary to establish a shower, a dressing room and a health care box. 

13.2 Into the radiation workplace, protective equipment must be worn; no food, water, smoking or food should be eaten in the radiation workplace; radiation workers must wash their hands and rinse their mouths before eating. The protective equipment used should be cleaned frequently and must not be brought back to the living area. 

13.3 In case of injury during radiation operation, it is necessary to decontaminate the wound around with the medical disinfectant in time and ask the doctor for treatment. 

14 Medical supervision

14.1 Any person engaged in geological radiation operation of uranium mines must carry out health examinations in accordance with the requirements of 10.1.3 of GB 8703 before employment. Those who do not meet the requirements of “basic health” shall not engage in this work. See Table K of GB 8703 for the health standards of radiation workers. 

14.2 Uranium geological radiation workers are subject to medical supervision. If the exposure dose equivalent is close to or may exceed the annual dose equivalent limit, the medical examination shall be performed once a year (dust operators shall add a chest radiograph); those who are less than three times the annual dose equivalent limit shall have a physical examination every two to three years; For those who are exposed to radioactive source accidents, if the radionuclide intake exceeds the annual intake limit by two times, the blood test should be carried out in time and necessary treatment should be carried out. 

14.3 The diagnosis of occupational diseases such as silicosis should be carried out by an occupational disease specialist hospital designated by the competent authority. 

14.4 Units engaged in uranium ore geological work shall have specialized (part-time) occupational health doctors responsible for occupational health management and establish a health record for radiation workers. The health file is kept for at least 30 years after the job is stopped. 

14.5 Personnel who are not suitable for geological radiation work in uranium mines must change jobs in a timely manner. 

14.6 Before the dust-proof measures are not completely solved, the cumulative sampling time shall not exceed 2a. 

14.7 The medical treatment of radiation workers subjected to abnormal irradiation shall be handled in accordance with the provisions of 10.2.3 to 10.2.5 of GB 8703. 

15 Monitoring

15.1 Personal Dose Monitoring:

15.1.1 Uranium ore geological downhole operations, ore crushing, high-grade ore model making and other radiation workers whose annual intake may exceed three tenths of the annual dose limit shall be monitored for personal internal dose and skin and clothing. Pollution monitoring.

15.1.2 Personnel engaged in radium standard source calibration and leak detection, personnel engaged in pit exploration operations in areas with a uranium ore grade greater than 0.5% and other radiation workers whose external dose may exceed three times the annual dose limit must be carried out. Irradiation personal dose monitoring. 

15.1.3 Radioactive source accidents and other abnormally exposed persons should conduct personal dose tracking monitoring in a timely manner. 

15.1.4 Persons whose internal and external exposure doses are greater than one-tenth of the annual limit, but are unlikely to exceed three-tenths of the annual dose limit, can be routinely monitored and worked through workplace sputum, scorpion and gamma external exposure. Time surveys are carried out to estimate, if necessary, individual dose monitoring of radon and gamma radiation for some representative staff. 

15.1.5 When the radiation worker's internal and external exposure dose is equal to or higher than three tenths of the annual dose limit, the cause should be identified and the corresponding radiation protection evaluation should be made. 

15.1.6 When the radiation staff is transferred, their personal dose file information should be transferred to the radiation health department of the new unit. The personal dose file should be kept 30a after the radiation worker has been out of radiation. 

15.1.7 When radiation workers are diagnosed with radiation damage, personal dose monitoring data must be used as a basis. 

15.2 Workplace Monitoring:

15.2.1 Routine monitoring should be carried out in radiation workplaces. 

15.2.2 Workplace monitoring projects should include:

a. The concentration of alpha potential in the air, the concentration of dust and the concentration of long-lived alpha radiation in air. 

b. gamma radiation levels. 

c. discharged wastewater uranium, radium, thorium, and the total content of α. 

d. Ventilation systems, “three wastes” treatment systems and the detection of the effects of protective equipment. 

15.2.3 The monitoring period of various types of radiation workplaces is shown in the monitoring cycle of the radiation workplace in the table.

15.3 Radiation Environment Monitoring:

15.3.1 Background survey before the commencement of radiation workplaces

15.3.1.1 For the excavation tunnels, hydrometallurgical workshops, medium-sized and above uranium deposits above the main road, and the mineral crushing samples, processing rooms and analysis rooms above Grade C, the background investigation shall be carried out before construction. 

15.3.1.2 Scope of the background investigation: excavation tunnels, hydrometallurgical plants and medium-sized ore deposits with a monitoring radius of 3000m and other radioactive workplaces of 1000m; with pollution sources as the center, 500, 1000, 2000 in the monitoring area respectively 3,000m or 50, 100, 500, 1000m are concentric circles, divided into 64 sub-areas according to 16 directions, and the sub-areas where the residents live and have close relationship with the residents and the dominant wind downwind sub-area are mainly investigated. The river should be investigated along its flow direction. If the background is monitored and the impact is large, the scope of the investigation should be expanded. 

15.3.1.3 Survey objects: surface water, atmosphere, sediment, soil and edible organisms. 

15.3.1.4 Investigation of nuclide: strontium and its daughters in the atmosphere; natural uranium, radium-226, natural strontium, strontium, soil and natural uranium in edible organisms, radium-226, natural sputum, total α, Pb-210, Po-210 should be further analyzed when the total α in the sample is high. 

15.3.1.5 Investigation time: once during the wet season and the dry period. 

15.3.2 Environmental monitoring and monitoring items, frequencies, nuclide and location in normal production, see Table 2. The scope of monitoring is the same as 15.3.1.2. 

15.4 In the event of a radioactive source loss such as radium, the dose-monitoring of the exposed person shall be carried out. When contaminated by the broken radium source, the surface of the victim's clothing and the exposed human body shall be monitored for alpha and beta surface contamination. Perform internal exposure monitoring. 

Table 2 Routine items, frequency, nuclide and location of the radiation environment

15.5 Monitoring analysis methods and quality assurance:

15.5.1 Monitoring and analysis methods are carried out according to relevant national standards. The methods for monitoring dust, mites, scorpions and γ external exposure are as follows:

a. The dust concentration is measured by the filter. 

b. The concentration of germanium is determined by the scintillation chamber method, the balloon method or the ionization chamber method. The cumulative measurement of the radon concentration can be performed by the track etching method. 

c. The radon potential of the radon progeny is determined by the Markov method or the Kuznets method. 

d. Individual gamma exposure, using a thermoluminescent dosimeter. 

15.5.2 Monitoring quality assurance must be carried out throughout the stages of monitoring program development, sample collection, storage, transportation, analysis and monitoring results evaluation. For specific quality assurance measures, refer to relevant regulations. 

15.6 Radiation protection assessment and radiation environmental quality assessment of radiation workplaces shall be carried out in accordance with relevant standards such as GB 8703 and GB 11215. 

15.7 The results of personal dose monitoring and radiation monitoring shall be reported to the supervisor and supervisory authority in the form of a table in Appendix B (Supplementary) and filed.

Appendix A

Annual intake limit (ALI) and derived air concentration (DAC) of common radionuclides in uranium geology, derived ingestion concentration (DIC)

(Supplementary)

Note: 1) ALI inhalation using its oxides and hydroxides. 

2 Uranium uses its ALI ingestion of water-soluble inorganic compounds and ALI inhalation of oxides. 

3 Refer to GB 9133 for the calculation method of publicly derived air concentration and derived ingestion concentration.

Appendix B

Comprehensive annual report on radiation monitoring data

(Supplementary)

Table B1 Radiation workers personal dose annual report type of work name number of people monitoring number of scorpion body dose mSv γ ray irradiation dose, mSvα aerosol dose, mSv total dose, mSv collective dose, person · mSv Remarks

Unit name: Unit responsible person:

Person in charge of security department: Fill in the form:

Date of filing: year, month and day

Additional information:

This standard was proposed by the China National Nuclear Corporation. 

This standard was drafted by the Nuclear Industry Geology Bureau. 

The main drafters of this standard are Lin Qingquan, Song Lanxuan, Zhang Zhiku, Zhang Hong, and Lao Jieyu.

Technical Supervision Bureau 1995-12-13

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