Thông tư 75/2017/TT-BTNMT về quy định bảo vệ nước dưới đất trong hoạt động khoan, đào, thăm dò, khai thác nước dưới đất

CIRCULAR

GROUNDWATER PROTECTION IN DRILLING, DIGGING, SURVEYING AND EXTRACTING GROUNDWATER

Pursuant to Law on Water Resources in 2012;

Pursuant to Decree No. 36/2017/ND-CP dated April 4, 2017 of the Government administering functions, tasks, powers, and organizational structure of Ministry of Natural Resources and Environment;

Pursuant to Decree No.201/2013/ND-CP dated November 27, 2013 of Government on elaborating to Law on Water Resources;

At the request of Director General of Department of Water Resources Management and Director of Department of Legal Affairs;

Minister of Natural Resources and Environment promulgates Circular on groundwater protection in drilling, digging, surveying and extracting groundwater.

Article 1. Scope

1. This Circular prescribes ground water protection in drilling, digging, surveying and extracting groundwater, including following activities: conducting survey and extracting ground water, conducting geological survey drilling, conducting geological survey drilling, conducting geological survey and extracting minerals, handling construction foundation, mine dewatering and other drilling and digging activities related to groundwater.

2. Drilling for petroleum exploration and extraction is not under the scope of this Circular.

Article 2. Regulated entities

This Circular applies to regulatory agencies managing water resource and organizations, individuals and households (hereinafter referred to as “organizations and individuals”) related to protection of groundwater in drilling, digging, surveying and extracting groundwater.

Article 3. Groundwater protection principles

1. Protect groundwater by focusing on preventive measures; prioritize protecting groundwater in areas susceptible to overextraction or severe deterioration, restricted or limited extraction areas, areas providing domestic water, urban areas, industrial zones, industrial clusters, export-processing zones, trade villages, populated areas, areas with water scarcity, areas whose groundwater is potentially susceptible to exhaustion, pollution, salt-water intrusion and areas potentially susceptible to depression.

2. Groundwater protection must accompany efficient extraction and use of groundwater resources, Protection of surface water, environment, forest and natural resources.

3. Groundwater protection must be considered and implemented when preparing plans related to water resource extraction and utilization. With respect to investment projects relating surveying, extracting and utilizing groundwater or including drilling and digging activities that affect groundwater quantity and quality, groundwater protection must be implemented during preparation phase of the projects.

Article 4. General requirements regarding groundwater protection in borehole and drilled well design and construction

During survey and extraction of groundwater, geological survey drilling, geological survey, mineral survey and extraction, handling of construction foundation, mine dewatering and other drilling and digging activities related to groundwater, organizations and individuals designing and constructing boreholes and drilled wells (hereinafter referred to as “drilled wells”) must:

1. Implement regulations under Circular No. 59/2015/TT-BTNMT dated December 14, 2015 of Minister of Natural Resources and Environment on techniques of drilling to survey, assess and explore groundwater.

2. Seal the bore of the drilled well and temporary casing with natural clay or anti-permeable materials similar to clay.         Reinforce and elevate the area within a radius of 1m around the drilled well opening with natural clay or other anti-permeable materials to prevent dirty water from falling into the drilled wells or seeping through the bores and cases of the drilled wells into the aquifers.

3. Not use wastewater, dirty water or water containing fats, oils or toxic substances as drilling fluids or to mix with drilling fluid and bring into the drilled well; not let fuel, fats and oils leak into the environment around the drilled well.

4. Ensure stability of soil around the drilled well area while drilling and conducting research and experiments in the drilled wells or while using the drilled wells.

5. In case of drilled wells expected to be used for 2 years or more, install casings and seal in order to prevent water from infiltrating aquifers or water in aquifers with different quality from seeping through the bores.

6. In case of depression or any other irregular incidents during drilled well construction or use, promptly cease construction and use in order to rectify the incidents and compensate for the damage (if any); promptly inform People’s Committees of communes, wards and towns (hereinafter referred to as “Commune-level People’s Committees”) and Departments of Natural Resources and Environment of provinces and central-affiliated cities (hereinafter referred to as “Departments of Natural Resources and Environment”) where the incidents occur.

7. Unused drilled wells or drilled wells that are damaged during construction and use must be disposed and sealed according to water resource laws.

Article 5. Requirements regarding drilled well design and construction for groundwater extraction

Organizations and individuals extracting groundwater must comply with Article 4 of this Circular and following specific requirements:

1. Designing drilled wells for groundwater extraction must be performed by persons primarily responsible for technical operations of organizations and individuals licensed for drilling for groundwater or persons responsible for technical operations of organizations and individuals providing consulting services for preparation of schemes and reports who are specified in applications for groundwater exploration and extraction license.

2. Drilled wells for groundwater extraction must be constructed by organizations and individuals licensed for drilling for groundwater according to water resource laws.

3. Casings and filter pipes installed in drilled wells for groundwater extraction must be pipes specialized for drilled wells for groundwater extraction and: specify code, number, standards and name of manufacturers; have thickness, mechanical and chemical properties satisfactory to soil profile, depth, diameter, useful life and chemical weathering properties of soil and water at the location of the drilled wells; ensure stability of the drilled wells throughout the useful life thereof.

4. Well heads that are installed above-ground must be at least 0.3m off the ground or surface of pump pads, or higher than average annual flood level in case of drilled wells situated in areas regularly susceptible to flood.

Basements where underground well heads are installed must be waterproofed to isolate from surface water; the area within 1.5m around the well heads must be elevated or raised to normal level and reinforced with concrete or cement grout to prevent dirty water from infiltrating into aquifers through the drilled wells.

5. Drawings for design of drilled well structure and construction methods shall be required and must be able to present following information:

a) Name of owners of the drilled wells and organizations, individuals designing the drilled wells;

b) Stratigraphic column, description of soil profile and depth of each soil layer at the drilled well location; type, diameter, thickness and depth of each section of casing and filter pipe; dimension and location of casing centralizers (if any);

c) Depth, thickness, type and dimension of filtering materials of each well screen section;

d) Depth, thickness and type of sealing materials of each section surrounding the casings. Sealing the outside of casings shall comply with Clause 6 of this Article;

dd) Extraction rate and estimated maximum static water level and pumping water level; diagrams of installation of extraction devices and devices monitoring water level and rate of extraction;

e) Dimensions of concrete section protecting well heads and elevation of the well heads;

g) Methods of installing filtering materials, sealing, inspecting and supervising well construction.

6. Sealing the outside of casings specified in Point d Clause 5 of this Article must satisfy following requirements:

a) The portion of at least 5m from the surface must be sealed with cement grouts;

b) The next portion leading to the top of the aquifers or top of filtering materials must be filled with cement grouts, cement grouts mixed with natural clay or bentonite;

c) In addition to requirements specified in Points a and b of this Clause, in case of a portion whose diameter exceeds the greatest outside diameter of casing by 250mm or a drilled well whose casing diameter is less than 60mm and depth does not exceed 30m, may use natural clay pebbles which are 0.25 times smaller than thickness of the seal as sealing materials.

d) In case of a drilled well simultaneously extracting water from at least 2 discontinuous aquifers, seal the sections in-between the aquifers as specified in Point b of this Clause;

dd) The seal must be at least 30mm thick in case of casings whose diameter is less than 60mm or at least 50mm thick for other cases.

7. Temporary casings must be installed at at least 3m below surface during drilled well construction; openings of such casings must be at least 0.2m off from the surface where well heads are situated and must be protected, maintained throughout the construction.

8. Materials utilized during drilled well construction must not contain toxic substances or pathogens and must be preserved in dry areas, away from potential pollutants. In case of using chemicals to submerge and clean drilled wells, the used chemicals must be permitted for use as per the law and must not pollute the environment and water sources.

Article 6. Requirements regarding designing and constructing drilled wells for exploration, investigation and assessment of groundwater resources, geological survey, mineral survey and extraction, foundation handling and mine and well dewatering

Organizations and individuals designing and constructing drilled wells must comply with Article 4 of this Circular and following specific requirements:

1. In case of drilled wells for exploration, investigation and assessment of groundwater resources:

a) In case a drilled well is utilized to extract groundwater, monitor over long period or expected to have useful life of at least 2 years, comply with Article 5 of this Article;

b) Drilled wells other than those specified in Point a of this Clause must be sealed from well heads to the highest point of aquifers or to the highest point of filtering materials.

2. In case of drilled wells for construction geological survey, geological survey, mineral survey and extraction, foundation handling and mine dewatering:

a) In case a drilled well is expected to have a useful life of at least 2 years, seal according to Clause 6 Article 5 of this Article;

b) In case of drilled wells other than those specified in Point a of this Clause, seal from the depth of 5m below ground level.

3. In case of dug wells:

a) The wells must be at least 10m away from husbandry farms, toilets, rubbish holes and other potential pollutants;

b) Headwalls must be constructed with bricks, rocks and concrete and must be at least 0.5m of the ground surface and watertight to prevent surface water from seeping into the wells.

Article 7. Requirements regarding groundwater protection during experiments in drilled wells

Organizations and individuals constructing and utilizing drilled wells while performing experiments within the drilled wells must satisfy following requirements:

1. Methods and process of experiments conducted inside the drilled wells must be fully presented in scientific research schemes, topics, projects and construction technical documents.  The experiments shall be conducted under examination and supervision of competent regulatory agencies.

2. In case of any incidents namely depression, cracking of surrounding buildings or constructions or other irregular events during the experiments, the experiments must be immediately stopped for rectification and compensation for damage (if any); promptly inform Commune-level People’s Committees and Departments of Natural Resources and Environment where the incidents occur.

3. Chemicals and radioactive substances used during the experiments must be permitted for use as per the law and must not be able to pollute the environment and water sources.

4. Prepare measures to prevent wastewater or water containing toxic substances from entering the drilled wells.

5. In case of experimenting suction pumps, in addition to regulations under Clauses 1, 2, 3 and 4 of this Article, following requirements must be met:

a) Water pumped to the surface must be collected and directed at least 10m away from the well heads in manner that does not cause inundation or affect surrounding environment;

b) Water level must not be dramatically declined which drastically impacts extraction of neighboring groundwater extraction structures;

c) In case water pumped to the surface shows irregular characteristics or kills animals or plants around the areas, immediately stop pumping to promptly rectify and compensate for any damage (if any); promptly inform Commune-level People’s Committees and Departments of Natural Resources and Environment where the accidents occur.

Article 8. Groundwater protection during extraction

1. Owners of groundwater extraction structures are responsible for maintaining hygiene in the well’s vicinity and adopting measures to prevent groundwater pollution via extraction wells.

2. Owners of groundwater extraction structures which serve providing domestic water must construct protection zones according to water resource laws.

3. Owners of extraction structures who are licensed for extraction and use of groundwater shall install equipment and assign personnel to monitor flow rate, water level and water quality at wells for extraction and wells for monitor of the structures satisfactory to figures, methods and regulations on monitor to provide and update figures in systems for monitoring water resource extraction and use of regulatory agencies according to water resource laws.

Monitoring water level at wells for monitor of extraction structures must be implemented at at least 1 well in case of structures whose flow rate ranges from 3,000 m³/24 hours to less than 5,000 m³/24 hours; at at least 2 wells in case of structures whose flow rate ranges from 5,000 m³/24 hours to less than 10,000 m³/24 hours; at at least 3 wells in case of structures whose flow rate reaches 10,000 m³/24 hours or higher.

4. Detect, handle and rectify irregular events or incidents regarding water quality or water level during extraction process and other incidents caused by the extraction process; in case of incidents, immediately stop the extraction, promptly rectify and compensate for any damage (if any); promptly inform Commune-level People’s Committees and Departments of Natural Resources and Environment where the incidents occur and report to agencies that issue license for groundwater extraction and use.

Article 9. Groundwater protection in investigation and assessment of groundwater resources, construction geological survey, geological survey, mineral survey, foundation handling and mine and well dewatering

1. Organizations and individuals drilling, digging or conducting experiments in wells while investigating, assessing groundwater resources, conducting construction geological survey, geological survey, mineral exploration and extraction, handling foundations and dewatering mines must comply with Articles 4, 6 and 7 of this Circular in addition to relevant regulations, standards and technical regulations.

2. Organizations and individuals handling foundations shall only use materials permitted for use as per the law; wastewater, dirty water or water containing fats and oils must not be used for handling foundations.

3. In case of draining water for mine dewatering, comply with Clause 4 Article 26 of Law on Water Resource dated 2012.

4. Reservoirs, tanks or areas containing wastewater, residues and other liquid waste produced during mineral extraction process must comply with environment protection requirements according to regulations and law on environment protection, minerals and water resources to prevent groundwater pollution.

Article 10. Entry into force

1. This Circular comes into force from February 12, 2018.

2. Chapter III, Chapter IV, Chapter V and Article 21 Chapter VI of Decision No. 15/2008/QD-BTNMT dated December 31, 2008 of Minister of Natural Resources and Environment on protection of groundwater resource shall expire from the effective date hereof.

Article 11. Implementation

1. Department of Water Resources Management is responsible for providing guidelines and examining implementation of this Circular.

2. Ministries, ministerial agencies, governmental agencies, People’s Committees of all levels, Departments of Natural Resources and Environment of provinces and central-affiliated cities and relevant organizations, individuals are responsible for the implementation of this Circular./.

3. Difficulties that arise during the implementation of this Circular should be reported to the Ministry of Natural Resources and Environment for consideration and revision./.