This Circular details the investigation, assessment, and exploitation of riverbed and reservoir sand and gravel deposits. It includes technical requirements, environmental monitoring methods, ecological impact predictions during exploitation, as well as third-level resource calculations and recommendations for prospective areas to transfer exploration and exploitation.
적용 범위
Agencies, organizations, and individuals carry out investigations, assessments, and exploitation of riverbed and reservoir sand and gravel deposits.
핵심 사항
- Technical requirements for sample collection and testing
- Environmental monitoring methods and ecological impact predictions during exploitation
- Methods for calculating third-level resources
- Recommendations for prospective areas to transfer exploration and exploitation.
- Effective from October 3, 2025
🌐 이 문서의 사회적 영향
- To ensure quality and efficiency in the investigation and assessment of riverbed and reservoir sand and gravel deposits.
- To support environmental impact predictions during exploitation to promptly address issues.
- To provide a legal basis for transferring exploration and exploitation of prospective areas.
❓ 자주 묻는 질문
Who does this Circular apply to?
It applies to agencies, organizations, and individuals conducting investigations, assessments, and exploitation of riverbed and reservoir sand and gravel deposits.
What are the technical requirements for sample collection and testing under this Circular?
Sample collection must represent the basic characteristics of the deposit; testing must determine the quality and reasonable, effective usability of the mineral.
How does this Circular stipulate environmental impact predictions during exploitation?
Information on bottom, surface flow, tides, waves must be collected; geological disaster conditions must be surveyed, and environmental monitoring must be combined with hydro-mechanical dynamic monitoring work.
What does this Circular stipulate regarding third-level resource calculations?
Resources are determined using geological block methods or specialized software; resources are calculated in cubic meters.
전문
| MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT |
SOCIALIST REPUBLIC OF VIET NAM Independence - Freedom - Happiness |
| Number: 49/2025/TT-BNNMT | Hanoi, August 19, 2025 |
CIRCULAR
Technical Regulations on Surveying and Evaluating Riverbed and Reservoir Sand and Gravel Deposits
_________________
Pursuant to the Law on Geology and Mineral Resources dated November 29, 2024;
Based on Decree No. 35/2025/NĐ-CP dated February 25, 2025 of the Government stipulating the functions, tasks, powers, and organizational structure of the Ministry of Agriculture and Rural Development;
At the proposal of the Director of the Vietnam Geological and Mineral Resources Administration;
The Minister of Agriculture and Environment promulgates this Circular stipulating technical regulations for surveying and evaluating riverbed and reservoir sand and gravel deposits.
PART I
GENERAL PROVISIONS
Article 1. Scope of Regulation
This Circular specifies the technical content of the work of surveying and evaluating riverbed and reservoir sand and gravel deposits for geological surveys of mineral resources.
This Circular does not apply to the surveying and evaluation of marine sand resources from the mouth of rivers towards the sea.
Article 2. Applicability
This Circular applies to state management agencies, organizations, and individuals related to activities of surveying and evaluating riverbed and reservoir sand and gravel deposits.
Article 3. Explanation of Terms
In this Circular, the following terms shall be understood as follows:
1. Riverbed and reservoir sand and gravel deposits refer to accumulations within riverbeds, alluvial plains, river shelves, river mouths, and reservoirs, including pebbles, gravel, grit, and sand used as construction materials.
2. River mouth boundary refers to the point where the river meets the sea, determined by a straight line connecting the outermost points of the lowest tidal water level over many years on both sides of the riverbank.
3. CBR sample is a test sample used to determine the CBR index, an important indicator for assessing the load-bearing capacity of soil and materials used in road construction and other works.
Article 4. Sequence and Proportion of Surveying and Evaluating Riverbed and Reservoir Sand and Gravel Deposits
1. Surveying and evaluating riverbed and reservoir sand and gravel deposits are divided into two stages:
a) Preliminary survey of riverbed and reservoir sand and gravel deposits to delineate the distribution range and quality of these deposits, predict class 334a resources, and delineate promising areas for transitioning to the evaluation stage;
b) Evaluation of riverbed and reservoir sand and gravel deposits to clarify the scale and quality of these deposits, assess class 333 resources, and delineate areas meeting conditions for inclusion in exploration, exploitation, processing, and utilization plans for mineral resources;
c) In cases where preliminary survey results have been obtained as prescribed in Point a Clause 1 of this Article, the evaluation work shall be carried out as prescribed in Point b Clause 1 of this Article.
2. Proportion of Surveying and Evaluating
a) Surveying riverbed and reservoir sand and gravel deposits at a scale of 1:50,000;
b) Evaluating riverbed and reservoir sand and gravel deposits at a scale of 1:10,000.
Article 5. Survey and Evaluation Network for Riverbed and Reservoir Sand and Gravel Deposits
1. Survey and evaluation lines are designed basically perpendicular to the length of the distribution area of riverbed and reservoir sand and gravel deposits or perpendicular to the direction of river flow (current) and the shoreline of the reservoir.
2. The survey and evaluation network is designed to suit the characteristics of the distribution, structural morphology, size of the riverbed and reservoir sand and gravel deposits, topographical features, patterns, and degree of variation in thickness and quality.
3. The network of survey and evaluation tasks shall be implemented in accordance with the provisions of Appendix I attached to this Circular.
4. The network of survey and evaluation structures shall refer to the provisions of Appendix II attached to this Circular.
Article 6. Establishing Original Documents and Digitization
1. The original documents for the work of investigating and assessing riverbed and lake sand and gravel resources shall be established in digital form, fully reflecting information as prescribed in Circular No. 43/2016/TT-BTNMT dated December 26, 2016, issued by the Minister of Natural Resources and Environment on technical regulations for collecting and establishing original documents in basic geological surveys and mineral exploration.
2. Tools, software, and applications used in the work of investigating and assessing riverbed and lake sand and gravel resources must ensure safety and confidentiality.
3. In cases where necessary, printing from updated digital files in the database system may be permitted.
Article 7. Classification of Geological Structure Complexity and Natural Condition Difficulty
1. The classification of geological structure complexity is applied to select networks of investigation and assessment works, and networks of investigation and assessment facilities for riverbed and lake sand and gravel resources. The classification of geological structure complexity is implemented according to Appendix III attached to this Circular.
2. The classification of natural condition difficulty is applied to determine economic-technical factors related to the implementation of the work of investigating and assessing riverbed and lake sand and gravel resources. The classification of natural condition difficulty is implemented according to Appendix IV attached to this Circular.
Article 8. Preparing Investigation and Assessment Plans for Riverbed and Lake Sand and Gravel Resources
1. Content of Work in Preparing the Plan
a) Collecting and compiling research and geological and mineral survey materials, environmental conditions in the investigation and assessment area;
b) Collecting materials on topographic features, geomorphology, riverbed depth; current bank erosion status; climatic and hydrological conditions in the investigation and assessment area;
c) Collecting materials on economic and cultural characteristics; infrastructure, economic activities, and environmental protection along the river; relevant water and land transportation networks in the investigation and assessment area;
Collecting legal basis materials, approved planning and investigation plans for geology and minerals; budget preparation bases;
d) Conducting preliminary surveys of the investigation area, determining construction conditions for the plan;
đ) Summarizing and processing materials, delineating potential areas for investigation and assessment;
e) Analyzing and summarizing materials, establishing current status diagrams, geological and mineral diagrams, proposed investigation and assessment area diagrams, and proposed facility layout diagrams within the investigation and assessment area;
g) Estimating costs, developing construction plans;
h) Preparing a project explanatory report.
2. The format of the plan is implemented according to Circular No. 33/2025/TT-BNNMT dated July 2, 2025, issued by the Minister of Agriculture and Environment on the establishment, review, approval of projects, tasks, reports on the results of basic geological surveys, geological surveys on minerals, and the publication of basic geological survey results.
Article 9. Reporting the Results of Investigating and Assessing Riverbed and Lake Sand and Gravel Resources
1. Content of Work in Preparing the Report on the Results of Mineral Resource Investigation
a) Processing and summarizing all types of project implementation materials;
b) Establishing drawings and accompanying explanations that accurately reflect the actual geological and mineral conditions in the investigation area;
c) Calculating class 334a mineral resources;
d) Delineating potential areas and proposing to move to the evaluation phase;
đ) Calculating incurred costs;
e) Writing the project result report.
2. Content of Work in Preparing the Report on the Results of Mineral Resource Evaluation
a) Processing and summarizing all types of project implementation materials;
b) Establishing drawings and accompanying explanations that accurately reflect the actual geological and mineral conditions in the evaluation area;
c) Calculating class 333 mineral resources;
d) Forecasting sediment balance and movement at the riverbed;
đ) Determining the potential uses and suitable extraction methods and technologies for riverbed and lake sand and gravel resources;
e) Delineating potential areas and proposing to move to exploration and exploitation phases;
g) Calculating incurred costs;
h) Writing the project result report.
3. Content and Presentation Format of the Report on Results
a) The report format follows the provisions of Circular No. 33/2025/TT-BNNMT;
b) The content and scientific requirements for specialized maps and accompanying explanatory reports follow technical industry regulations.
Chapter II
Article 10. Investigation of Riverbed and Reservoir Sand and Gravel Deposits
Article 10. Contents of the investigation of riverbed and reservoir sand and gravel deposits
1. Collecting, compiling, and processing documents.
2. Interpreting remote sensing data.
3. Geodetic work.
4. Geophysical work.
5. Investigating and mapping geological and mineral resources of riverbed and reservoir sand and gravel deposits at a scale of 1:50,000.
6. Investigating and mapping engineering geology at a scale of 1:50,000.
7. Studying geomorphology, geological disasters such as subsidence and bank collapse.
8. Implementing investigation works: drilling to study geological structure, engineering geology, determining sand-bearing structures, checking and interpreting quantitative seismic reflection data; constructing pits, wells, drilling, and vibration tubes to assess resource grade 334a.
9. Sampling, processing, and analyzing samples.
10. Compiling, processing documents, delineating, and selecting promising areas for proposal to move to the evaluation phase.
Article 11. Contents of collecting, compiling, and processing documents
1. Collecting and compiling documents related to mineral activities: exploration, mining of minerals, reports on mineral activities, planning for exploration and mining of minerals, prohibited and temporarily prohibited mineral activity zones.
2. Collecting and compiling documents on the investigation and assessment of riverbed and reservoir sand and gravel deposits.
3. Collecting and compiling documents on hydrogeological and engineering geological investigations.
4. Collecting and compiling documents on urban geological investigations.
5. Collecting and compiling documents on the investigation and reporting of geological disasters (subsidence, bank collapse).
6. Collecting hydrological monitoring data from the national monitoring network and specialized meteorological and hydrological monitoring.
7. Processing and creating current status maps for the investigation, assessment, exploration, and exploitation of riverbed and reservoir sand and gravel deposits; current status of geological disasters (subsidence, bank collapse); delineating potential areas for investigation and assessment of sand and gravel deposits.
Article 12. Interpretation of Remote Sensing Data
1. Interpreting remote sensing data and maps from different periods to clarify the current state and trends of erosion-deposition along the river course.
2. Clarifying geological structure, geomorphological characteristics, structural features, delineating ancient riverbed and ancient bar sand signs, meandering corridors, and channel migration processes on the main river.
3. Establishing longitudinal shoreline change diagrams along the main river.
4. Establishing geological and geomorphological diagrams of the investigation area.
Article 13. Geodetic Work
1. Implementation Content
a) Collecting and compiling topographic maps of the investigation area;
b) Geodetic positioning and route guidance: positioning and guiding for geophysical work (high-resolution seismic reflection and sonar scanning slope measurement), establishing geophysical survey route diagrams, determining coordinates and elevations of observation points;
c) Measuring depths along the route using echo sounders combined with sonar slope scanning to create river bottom topography diagrams of the investigation areas, simultaneously combining monitoring data to calculate sediment inflow and outflow volumes, serving to build sediment transport models;
d) Surveying construction projects and monitoring stations onto maps;
e) Water level monitoring.
2. Technical Requirements
a) Route guidance geodetic positioning and depth measurement along the route using echo sounders shall be carried out according to Circular No. 34/2024/TT-BTNMT dated December 16, 2024, stipulating technical procedures for building national geographic database at a scale of 1:50,000 using echo sounding methods and creating seabed topography maps from the corresponding national geographic database;
b) Determining coordinates and depths of construction projects using satellite positioning technology GNSS according to Circular No. 34/2024/TT-BTNMT;
c) Water level monitoring shall be carried out according to Circular No. 34/2024/TT-BTNMT.
3. Products
a) Original documents;
b) Geophysical survey route diagram at a scale of 1:50,000;
c) Geodetic work report;
d) River bottom topography diagram.
Article 14. Geophysical Work
1. High-resolution shallow seismic survey
a) Content of implementation
- Conduct high-resolution shallow seismic surveys along designed lines;
- Determine and predict the distribution characteristics, thickness, boundary morphology of geological formations, and stratigraphic division according to different lithological components up to the depth of investigation;
- Establish thickness contour maps of seismic groups and bottom structure morphology of seismic groups.
b) Technical requirements
- High-resolution shallow seismic surveys shall be carried out in accordance with the following TCVNs: TCVN 12298-1:2018 on Mineral Exploration, Evaluation, and Survey - High-resolution shallow seismic survey method on sea; TCVN 12298-2:2018 on Mineral Exploration, Evaluation, and Survey - Method for processing and analyzing high-resolution shallow seismic tapes on sea; TCVN 12298-3:2018 on Mineral Exploration, Evaluation, and Survey - Part 3: Method for determining the quality of high-resolution shallow seismic data on sea;
- The materials and results of high-resolution shallow seismic surveys must be compared and contrasted with construction investigation materials to calibrate and check.
c) Products
- Field diary of high-resolution shallow seismic survey work;
- Diagrams of high-resolution shallow seismic survey lines, tapes (including original tapes, original data files, and processed tapes);
- Geological and geophysical cross-sections showing boundaries of sedimentary layers and other geological factors;
- Illustrative drawings of seismic materials, thickness contour maps of seismic groups, bottom structure morphology of seismic groups;
- Report on the results of high-resolution shallow seismic survey work.
2. Side-scan sonar profiling
a) Content of implementation
- Collecting bottom river topography features, predicting sediment composition and changes in bottom river sediment characteristics;
- Identifying characteristic bottom river terrain and landform elements, positions of abnormalities on the river bottom;
b) Technical requirements:
- Scan width ≥ 15 meters each side;
- Resolution ≤ 10 cm;
- Quality of side-scan sonar materials is evaluated based on images obtained at the intersection points between the main survey line and the verification line. At the intersection point, visually examine the images of two tapes and compare them to determine their similarity for evaluation. The verification line is designed to coincide with the verification line of the high-resolution shallow seismic method.
c) Implementation procedure
- Install machinery and equipment;
- Measure and select parameters to obtain field data with the best quality and minimize background noise;
- Adjust the winch up and down to position the towfish at an appropriate distance from the bottom, avoiding noise caused by ship propellers and waves; prevent the towfish from colliding with submerged rocks;
- Data retention includes: original data files in device format standards; data converted to *.tif format;
- Record field diary;
- Remove machinery and equipment;
- Process materials using specialized software after completing the survey line, serving geological survey work.
d) Products
- Field diary of side-scan sonar profiling work;
- Diagram of side-scan sonar profiling lines;
- Set of side-scan sonar image materials collected about the river bottom (including original files integrated with coordinates; side-scan tapes connected by specialized software to fully reflect bottom topography and surface sediment characteristics);
- River bottom surface diagram based on side-scan sonar profiling material processing results;
- Report on the implementation results.
Article 15. Survey and create geological maps of riverbed and lake sand and gravel at a scale of 1:50,000
1. Conduct surveys to collect information on the physical components and structure of geological formations.
2. Combine processing and synthesizing geophysical data and construction project investigation materials to determine geological and mineral characteristics and structural features.
3. Define the distribution areas of riverbed and lake sand and gravel deposits, as well as areas that have been explored and mined.
Article 16. Survey and create engineering geological maps at a scale of 1:50,000
1. Conduct surveys to create engineering geological maps at a scale of 1:50,000 to clarify geological-environmental risks such as the potential for riverbank erosion, riverbed scouring, changes in water flow, sedimentation, and channel migration.
2. The scope of surveying and creating engineering geological maps at a scale of 1:50,000 is determined according to specific projects.
3. Implementation Content
a) Conduct surveys to gather information on the characteristics of engineering geological conditions and geodynamic processes;
b) Collect and analyze various types of mechanical and experimental samples;
c) Classify layers of engineering geological formations;
d) Collaborate with geological studies to investigate geological and engineering geological features in areas prone to riverbank collapse and subsidence.
4. Technical Requirements
Engineering geological mapping shall be carried out in accordance with the regulations for engineering geological mapping at a scale of 1:50,000 (1:25,000) issued together with Decision No. 54/2000/QĐ-BCN dated September 14, 2000, by the Minister of Industry.
Article 17. Study of geomorphology and geological disasters such as subsidence and riverbank collapse
1. Analyze multi-temporal remote sensing images combined with GIS and historical topographic data to monitor the movement patterns of riverbanks, identifying signs of riverbed displacement over space and time.
2. Identify geological objects, geomorphic images, structural features, and ancient riverbed and sandbar indicators as a basis for investigating, surveying, analyzing, and evaluating riverbed and lake sand and gravel deposits.
3. Study geomorphological and neotectonic characteristics.
4. Define areas of subsidence and riverbank collapse and warn of the risk of geological disasters such as subsidence and riverbank collapse.
5. Calculate the degree of riverbank movement based on scale, speed, trend of bank movement, and erosion-deposition.
Article 18. Construction of Projects
1. Investigation projects are designed based on comprehensive geological, geomorphological, geophysical, and related data. The network of investigation projects refers to Appendix II issued together with this Circular.
2. Select appropriate project types based on water depth, construction conditions, and equipment capacity.
3. Construction of boreholes and wells shall be carried out in accordance with Circular No. 16/2020/TT-BTNMT dated December 18, 2020, issued by the Minister of Natural Resources and Environment, which stipulates technical requirements for excavation work and sample collection at mining sites.
4. Vibration-driven pipe installation shall be carried out in accordance with Circular No. 25/2010/TT-BTNMT dated October 27, 2010, issued by the Minister of Natural Resources and Environment, which stipulates technical requirements for eleven geological and mineral survey tasks in marine and island environments.
5. Drilling operations shall be conducted in accordance with the provisions governing drilling construction work in geological surveys for minerals.
6. Sampling rate for machine-drilled projects must be ≥ 80%.
7. Collection and establishment of original documentation shall be carried out in accordance with Article 6 of this Circular.
8. Products
a) Field data diagrams, project design drawings, statistical records;
b) Composite stratigraphic columns of projects clearly showing the characteristics of riverbed and lake sand and gravel layers including: depth of distribution, thickness, layering, interlayering; sediment composition, structure, color of each layer, and supplemented with analytical results;
c) Sample collection logs;
d) Photographs of projects and various types of samples.
Article 19. Sampling, processing, and analysis of samples
1. Sample for particle size analysis
a) Sampling at drilling projects where riverbed sand and gravel, reservoir bed sand and gravel have been identified. The sample length should be from 2 meters to 4 meters depending on the thickness and uniformity of the mineral deposit. The sample is taken by splitting the drill core in half, with one half retained in a tray and the other half processed according to the principle of bisecting, reducing, and selecting 1.0 to 2.0 kilograms for particle size analysis. Each drill hole should take three to four samples;
b) Sample analysis: particle size analysis using sieve and hydrometer methods in accordance with TCVN 4198:2014 on Construction Soil - Particle Size Analysis Method in Laboratory; TCVN 7572-2:2006 on Aggregates for Concrete and Mortar - Test Methods - Part 2: Determination of Particle Size; AASHTO: M145-91(2004) on Classification of Soils and Synthetic Soil Mixtures for Highway Construction Purposes.
2. Sample for mechanical and physical property analysis
a) Sampling: sampling in the original state within the column of the project being evaluated, representative of the body of riverbed and reservoir sand and gravel. Ensure that each sediment layer has one comprehensive mechanical sample to determine the mechanical properties of the sand and gravel bodies and underlying sediment formations. Samples are taken from drill holes, trenches, or outcrops with a sample length of 25 centimeters, following TCVN 2683:2012 on Construction Soil - Sampling, Packaging, Transport, and Preservation of Samples. Each drill hole should take two to four samples;
b) Sample analysis: analyzing moisture content, bulk density, natural volume density, void volume density, compacted volume density, clay and silt content, organic impurity content, dry angle of repose, wet angle of repose. Analysis methods follow the standards specified in TCVN 7572:2006 on Aggregates for Concrete and Mortar;
c) Result processing: determining voids ratio, compacted voids ratio, noting, and evaluating the mechanical properties of the mineral body and riverbed and reservoir sand and gravel materials.
3. Comprehensive quantitative sample
a) Group sampling according to drill holes on representative cross-sections within the body of riverbed and reservoir sand and gravel.
b) Sample analysis: determining mineral content by particle size grade related to resource criteria; analyzing particle size parameters (mean diameter, sorting coefficient, skewness coefficient). Sample analysis follows TCVN 4198:2014 on Construction Soil - Particle Size Analysis Method in Laboratory.
c) Result processing: preliminary interpretation of the environment and transport processes of sediments and percentage of particle size grades.
4. Thin section analysis of loose sediment
a) Sampling: samples are taken according to drill holes on representative cross-sections within the body of riverbed and reservoir sand and gravel with a weight of 0.5 to 1 kilogram. Sampling is done by product layer according to the project on representative cross-sections for the mineral body;
b) Sample analysis: analyzing basic characteristics of sand minerals, interpreting sediment origin. Main minerals include: quartz, feldspar, mica (biotite, muscovite), zircon, tourmaline, rutile, garnet, etc.;
c) Result processing: summarizing analysis results, accurately determining the origin, sedimentary environment, and geological history of the research area.
5. Heavy mineral sample
a) Sampling: representative sampling at the project site; heavy mineral comprehensive group sampling according to drill holes on representative cross-sections within the body of riverbed and reservoir sand and gravel. Samples are taken from drill holes, trenches, or outcrops, with each sample sent for analysis weighing 0.5 to 1 kilogram, following the principle of bisecting, reducing, and retaining the remainder in a tray;
b) Sample analysis: identifying mineral types such as quartz, feldspar, mica, amphibole, pyroxene, zircon, rutile, ilmenite;
c) Result processing: commenting and evaluating valuable heavy minerals, sedimentary geology (determining river and swamp deposition environments), petrology (tracing parent rock origins), engineering geology, and environmental aspects (evaluating soil stability, mechanical strength, water permeability).
6. Comprehensive silicate sample for determining the main oxide composition of riverbed and reservoir sand and gravel: SiO2, Al2O3, FeO, Fe2O3, CaO, Na2O, K2O, MgO, MKN.
a) Sampling: group sampling according to drill holes on representative cross-sections within the body of riverbed and reservoir sand and gravel. Sample weight: 1.0 kilogram/sample;
b) Sample processing and analysis: carried out according to the following standards:
TCVN 9910:2013 on Silicate Soil, Rock, and Ore - Determination of Total Iron Content - Photometric Method;
TCVN 9911:2013 on Silicate Soil, Rock, and Ore - Determination of Silicon Dioxide Content - Gravimetric Method;
TCVN 9912:2013 on Silicate Soil, Rock, and Ore - Determination of Calcium Oxide Content - Complexometric Titration Method;
TCVN 9914:2013 on Silicate Soil, Rock, and Ore - Determination of Total Iron Content - Titration Method;
TCVN 9915:2013 on Silicate Soil, Rock, and Ore - Determination of Aluminum Oxide Content - Complexometric Titration Method;
TCVN 9916:2013 on Silicate Soil, Rock, and Ore - Determination of Magnesium Oxide Content by Complexometric Titration Method;
TCVN 9917:2013 on Silicate Soil, Rock, and Ore - Determination of Potassium, Sodium, Lithium, Rubidium, and Cesium Elements.
7. Total radioactivity activity
a) Group sampling according to projects on representative cross-sections within the body of riverbed and reservoir sand and gravel in accordance with TCVN 10758-2:2016 (ISO 18589-2:2015) on Radioactivity Measurement in the Environment - Soil - Part 2: Strategic Sampling Guidance, Sampling, and Initial Sample Processing;
b) Sample analysis is carried out according to TCVN 10758-6:2016 (ISO 18589-6:2009) on Radioactivity Measurement in the Environment - Soil - Part 6: Measurement of Total Alpha Activity and Total Beta Activity or equivalent standards.
8. Small bulk density sample
a) Sampling: sampling in the original state within the column of the project, representative of the body of riverbed and reservoir sand and gravel. Ensure that each sediment layer has one sample. Samples are taken from drill holes, trenches, or outcrops with a sample length of 25 centimeters, following TCVN 2683:2012 on Construction Soil - Sampling, Packaging, Transport, and Preservation of Samples. Each drill hole should take two to four samples;
b) Sample analysis: analyzing indicators such as moisture content, natural volume density, bulk density. Sample analysis follows TCVN 4201:2012 on Construction Soil - Laboratory Method for Determining Standard Density.
c) Processing results: calculate dry bulk density indices, porosity, and saturation rates.
9. Chloride (Cl-) component analysis sample
a) Sample collection: collect group samples from drill holes on representative cross-sections within the sand and gravel riverbed and lakebed layers. The sample weight should be between 0.5 to 1.0 kg/sample, collected according to the standards specified in TCVN 7570-2006 regarding Aggregates for Concrete and Mortar.
b) Sample processing and analysis: process the sample to particle size
c) Processing results: assess the degree of salinity in the sand, identify the presence of ions affecting construction material properties according to TCVN 13754:2023 on Saline Sand for Concrete and Mortar.
10. Loose Bulk Density Sample
a) Sampling: sampling in the original state within the column of the project, representative of the body of riverbed and reservoir sand and gravel. Ensure that each sediment layer has one sample. Samples are taken from drill holes, trenches, or outcrops with a sample length of 25 centimeters, following TCVN 2683:2012 on Construction Soil - Sampling, Packaging, Transport, and Preservation of Samples. Each drill hole should take two to four samples;
b) Sample analysis: analyze natural bulk density, loose bulk density (porous bulk density). Analyze the sample according to TCVN 4201:2012 on Construction Soil - Laboratory Method for Determining Standard Density.
c) Processing results: calculate and determine the loose bulk density coefficient (by volume) of the mineral (sand).
11. Standard Compaction Sample
a) Sample collection: at determined boreholes for sand and gravel riverbed and lakebed projects. Samples are taken with lengths ranging from 2m to 4m depending on layer thickness and uniformity. Samples are taken from boreholes, trenches, or exposures with each sample weighing more than 15 kg, following the principle of top-bottom division and reduction for analysis, with the remainder stored in trays. Sampling follows TCVN 2683:2012 on Construction Soil - Sampling, Packaging, Transport, and Storage of Samples. Each borehole collects three to five samples.
b) Sample analysis: analyze the maximum bulk density corresponding to moisture content according to TCVN 12790:2020 on Crushed Stone and Gravel Used in Transportation Projects - Proctor Compaction.
c) Processing results: process results, plot correlation graphs between bulk density and moisture content.
12. CBR Sample
a) Sample collection: samples are taken at determined boreholes for sand and gravel riverbed and lakebed projects. Samples are taken with lengths ranging from 2m to 4m depending on layer thickness and uniformity. Samples are taken from boreholes, trenches, or exposures with each sample weighing between 30 to 40 kg, following the principle of top-bottom division and reduction for analysis, with the remainder stored in trays. Sampling follows TCVN 2683:2012 on Construction Soil - Sampling, Packaging, Transport, and Storage of Samples. Each borehole collects one sample.
b) Sample analysis:
- Particle composition analysis conducted according to TCVN 7572-4:2006 on Aggregates for Concrete and Mortar - Testing Methods;
- Natural moisture content analysis conducted according to TCVN 4196:2012 on Construction Soil - Laboratory Method for Determining Moisture Content and Hygroscopicity;
- Natural and dry bulk density analysis conducted according to TCVN 4202:2012 on Construction Soil - Laboratory Method for Determining Bulk Density;
- Unit weight analysis conducted according to TCVN 4195:2012 on Construction Soil - Laboratory Method for Determining Unit Weight;
- Standard Proctor compaction analysis conducted according to TCVN 4200-2:2012 on Construction Soil - Laboratory Method for Determining Compression Characteristics; TCVN 12790:2020 on Crushed Stone and Gravel Used in Transportation Projects - Proctor Compaction;
- CBR index analysis conducted according to TCVN 4200-5:2012 on Construction Soil - Laboratory Method for Determining Compression Characteristics.
c) Processing results: evaluate and compare the dry bulk density of the sample with the maximum bulk density to assess the degree of compaction achieved.
13. Organic Impurities Sample
a) Sample collection: at determined boreholes for sand and gravel riverbed and lakebed projects. Samples are taken with lengths ranging from 2m to 4m depending on layer thickness and uniformity. Samples are taken from boreholes, trenches, or exposures with each sample weighing between 1 to 2 kg, following the principle of top-bottom division and reduction for analysis, with the remainder stored in trays. Sampling follows TCVN 7572-1:2006 on Aggregates for Concrete and Mortar - Testing Methods - Part 1: Sampling. Each borehole collects three to five samples.
b) Sample analysis: conduct analysis according to TCVN 7572-9:2016 on Aggregates for Concrete and Mortar - Testing Methods - Part 9: Determining Organic Impurities.
c) Processing results: organic impurities in the sand are evaluated according to TCVN 7572-9:2016 on Aggregates for Concrete and Mortar - Testing Methods - Part 9: Determining Organic Impurities.
14. Small Aggregate Test Sample
Determine technical characteristics of aggregates used in concrete and mortar production including specific gravity; dry surface bulk density; porous bulk density; porosity; modulus of elasticity; gradation; clay and silt content; clay lumps and other coarse impurities; organic impurities; alkali-silica reactivity. Sampling and testing methods follow the provisions of TCVN 7572-2006 on Aggregates for Concrete and Mortar; TCVN 7570-2006 on Technical Requirements for Aggregates for Concrete and Mortar.
15. Surface Water Sample
Conduct physical and chemical component determination including: pH, Color, Odor, Electrical Conductivity; chemical properties including: SiO2 (mg/l), CO2 (mg/l), Hardness (meq/l); Cations: Na+, K+, Ca2+, Mg2+, NH4+, Fe2+, Fe3+, Al3+; Anions: HCO3-, Cl-, SO42-, NO3-, NO2-, CO32- and calculated total Cations, total Anions, total mineralization. Collection and analysis of surface water samples follow the regulations stipulated in Circular No. 10/2021/TT-BTNMT issued by the Minister of Natural Resources and Environment on environmental monitoring techniques and management of environmental quality monitoring information and data.
16. Technical (Technology) Sample
a) Sample collection: collect large representative samples of sand and gravel riverbed and lakebed through trial suction.
b) Analysis criteria: particle composition, modulus of elasticity; porous bulk density, unit weight, void ratio, dry bulk density, saturated bulk density, clay and silt impurities, organic impurities, surface dry bulk density at saturation moisture content, chloride content, SO3 content, expansion of mortar sample after 14 days in 1M NaOH at 80°C.
c) Processing results: evaluate the usability of sand and gravel riverbed and lakebed in both unprocessed and processed states.
Article 20. Compilation of documents, estimation of resources, delineation, and proposal of areas with potential
1. Estimation of level 334a resources
a) Documents used for estimating sand and gravel mineral resources include: results of riverbed surface layer surveys, geophysical measurement results delineating sand and gravel layers that have been verified by construction projects; quality analysis results of sand and gravel;
b) Method of resource estimation: using geological block method, encouraging the use of specialized software when estimating sand and gravel resources;
c) Resources are estimated in cubic meters.
2. Propose areas with potential sand and gravel mineral resources to transfer to the evaluation phase based on criteria specific to each area, resources, and exploitation purposes.
Article 21. Products of sand and gravel mineral survey in riverbeds and lake beds
1. The report on the results of the sand and gravel mineral survey in riverbeds and lake beds reflects comprehensively, truthfully, and scientifically all achieved results; clarifies the current geological conditions, mineral resources, exploration, and exploitation status within the surveyed area; delineates areas at risk of geological disasters (subsidence, riverbank erosion); delineates areas with potential sand and gravel mineral resources in riverbeds and lake beds for proposal to transfer to the evaluation phase.
2. Accompanying drawings and appendices must reflect the entire results of each project phase.
3. Original documentation system implemented according to Article 6 of this Circular.
Chapter III
EVALUATION OF SAND AND GRAVEL MINERALS IN RIVERBEDS AND LAKE BEDS
Article 22. Content of sand and gravel mineral evaluation in riverbeds and lake beds
1. Collection, compilation, and processing of existing documents.
2. Surveying work.
3. Geophysical work.
4. Preparation of a geological map of sand and gravel minerals in riverbeds and lake beds at a scale of 1:10,000.
5. Construction of evaluation works.
6. Sampling, processing, and analysis.
7. Monitoring and measuring the amount of sand replenishment and sediment material movement at the riverbed bottom.
8. Determination of usability.
9. Preliminary prediction of the impact of sand and gravel mineral extraction activities in riverbeds and lake beds on the environment.
10. Compilation of documents, estimation of level 333 resources, delineation, and proposal of areas with potential sand and gravel mineral resources in riverbeds and lake beds for transfer to exploration and exploitation phases.
Article 23. Surveying Work
1. Scope of work
a) Surveying positioning, depth measurement along the line using echo sounders, determination of coordinates and depths of structures, river water level monitoring carried out according to Article 13 of this Circular;
b) Establishment of control grids for coordinates and elevations;
c) Mapping of riverbed depth at a scale of 1:10,000 to serve the preparation of thematic maps of the project and resource estimation work for sand and gravel minerals in riverbeds and lake beds.
2. Technical Requirements
a) Establishment of control grids for coordinates and elevations: according to QCVN 04:2009/BTNMT national technical regulation on coordinate grid establishment; QCVN 11:2008/BTNMT national technical regulation on elevation grid establishment;
b) Riverbed depth map at a scale of 1:10,000 with basic contour intervals of 1 meter; technical regulations implemented according to Circular No. 12/2020/TT-BTNMT dated September 30, 2020 issued by the Minister of Natural Resources and Environment regarding technical regulations on the content and symbols of national topographic maps at scales of 1:10,000 and 1:25,000.
3. Products
a) Original documents;
b) Geophysical survey line diagram at a scale of 1:10,000;
c) Riverbed depth map at a scale of 1:10,000;
d) Report on surveying work results.
Article 24. Geophysical Work
Geophysical work shall be carried out in accordance with the provisions of Article 14 of this Circular.
Article 25. Preparation of Geological Maps for River and Lake Sand and Gravel Deposits at Scale 1:10,000
1. Scope of work
a) Implement construction according to the network specified in Appendix I attached to this Circular;
b) Synthesize, analyze, and process geological, topographical, and geophysical data to design evaluation works;
c) Compile the results of geophysical, topographical, and riverbed geomorphological measurements; the results of evaluation work construction; and sample analysis results to calculate resources of river and lake sand and gravel deposits.
2. Products
a) Geological diary;
b) Collected samples;
c) Photographic materials;
d) Actual condition maps fully displaying all construction items and quantities: survey lines and stations, sampling locations; evaluation works; monitoring stations;
đ) Geological and mineral maps of river and lake sand and gravel deposits established at scale 1:10,000;
e) Report on the implementation results.
Article 26. Construction of Evaluation Works
The construction content of evaluation works and sample collection within evaluation works shall be carried out in accordance with the provisions of Article 18 of this Circular.
Article 27. Sample Collection, Processing, and Analysis
The content of sample collection, processing, and analysis shall be carried out in accordance with the provisions of Article 19 of this Circular.
Article 28. Monitoring Current Conditions and Preliminary Assessment of River Bed Erosion and Deposition
1. Current condition monitoring and preliminary assessment of river bed erosion and deposition shall be applied within each river section or key river areas with significant changes; monitoring activities shall be conducted along fixed routes, and additional routes may be added based on annual changes in the riverbed and shoreline.
2. The monitoring cycle shall be conducted twice per year (once during the dry season and once during the flood season). Continuous 7-day monitoring at one station per cycle. Meteorological and hydrodynamic monitoring at river stations once per hour. Meteorological and shoreline monitoring at riverbank stations once per hour. Continuous sediment bottom sampling twice daily for seven days. Continuous recording of sediment deposition rates for seven days. Monitoring frequency is once per hour. Conduct four monitoring sessions per day at fixed times. Monitoring station density in the watershed must not exceed 100 km² per station; the distance between adjacent stations must not exceed 15 km.
3. Current condition monitoring and preliminary assessment of river bed erosion and deposition shall be carried out in accordance with TCVN 8303:2022 on procedures for river bed and coastal dynamics surveys and assessments.
Article 29. Determination of the Usability of River and Lake Sand and Gravel Deposits
1. Technical sample testing to determine suitable construction materials that can be used from river and lake sand and gravel deposits (aggregates for mortar, fine aggregates for concrete, fill material). The quality of river and lake sand and gravel deposits used in construction and transportation must meet national technical standards.
2. Technical samples must assess the usability of river and lake sand and gravel deposits in their raw state, after washing, and after processing. Based on this, propose usage fields for river and lake sand and gravel deposits for different ore bodies.
Article 30. Preliminary Environmental Impact Assessment of Sand and Gravel Mining Activities on the Environment
1. Collect and compile parameters related to bottom flow, surface flow, tides, waves, and physical factors of the river; trends in sediment movement (erosion zones, accumulation, and balance).
2. Conduct surveys to collect information on surface sediment layers and water environment, take representative samples to assess the current state of sediment quality according to QCVN 43:2025/BNNMT national technical regulation on sediment quality. Water environment needs to identify signs of pollution caused by human activities (oil slicks, waste, other pollutants), evaluate dispersion potential under hydrological conditions; measure and collect parameters; take and analyze representative surface water samples according to QCVN 08:2023/BTNMT national technical regulation on surface water quality to assess the current state of surface water environment quality.
3. Survey current geological disasters, including: riverbank erosion, channel filling, subsidence, environmental pollution, sand flow, erosion, landslides.
4. Monitor the environment in conjunction with hydro-meteorological monitoring work.
5. Evaluate flow regime; waves; water level; trend of near-bottom mud and sand transport; characteristics of bank erosion and accretion; predict impacts on the stability of the riverbed, banks, and beaches and environmental pollution when mining.
6. The preliminary environmental impact assessment results of sand and gravel mining activities require expert opinions from relevant fields before officially reporting to competent authorities.
Article 31. Requirements for Evaluation Level and Resource Boundary Delimitation at Level 333
1. Requirements for Evaluation Level of River and Reservoir Bed Sand and Gravel Resources
a) Determine basic characteristics regarding shape and distribution of ore bodies;
b) Determine thickness, structure, and stability of ore bodies;
c) Ore quality is determined based on analysis results of samples from evaluation works in the assessment area;
d) Technical sample analysis has been conducted to determine basic technological properties, reasonable and effective use of river and reservoir bed sand and gravel resources;
đ) A preliminary assessment and prediction of the impact of sand and gravel mining activities on the ecological environment have been conducted; solutions to mitigate and protect the environment have been proposed;
2. Requirements for Resource Boundary Delimitation
a) Resource boundaries at level 333 are delineated within the range of river and reservoir bed sand and gravel bodies, based on evaluation works meeting resource calculation criteria, allowing limited extrapolation based on geological, geomorphological, geophysical data or higher-level resource block boundaries;
b) The reliability of level 333 resources must be at least 20%.
Article 32. Compilation of Documentation, Calculation of Level 333 Resources, Delineation, and Proposal of Prospective Areas for Sand and Gravel Exploration and Mining
1. Calculation of Level 333 Resources
a) Resource calculation criteria for river and reservoir bed sand and gravel are determined according to the project proposal;
b) Resource calculation method: using geological block method or specialized software; resources are calculated in cubic meters;
c) For accompanying valuable minerals, depending on their variation compared to the main mineral and their concentration, they may be classified at the same level or reduced by one level.
2. Delineation of Prospective Areas for Transfer to Exploration and Mining: Compile evaluation results, related socio-economic factors, and delineate areas with conditions suitable for transfer to exploration and mining.
Article 33. Mineral assessment products for riverbed sand and gravel, lake sand and gravel
1. The report on the results of mineral assessment for riverbed sand and gravel, lake sand and gravel shall reflect all outcomes of each project component; forecast the impacts and effects of extracting riverbed sand and gravel, lake sand and gravel on the environment; delineate areas with conditions suitable for transferring exploration and exploitation.
2. The drawings and appendices accompanying shall reflect all outcomes of each project component at each stage.
3. The original documentation system as prescribed in Article 6 of this Circular.
Chapter IV
IMPLEMENTING PROVISIONS
Article 34. Effective Date
1. This Circular takes effect from October 3, 2025.
2. In cases where referenced documents in this Circular are amended, supplemented, or replaced, they shall be implemented according to the new provisions.
Article 35. Implementation
1. The Head of the Ministry's Office, heads of agencies, organizations, and individuals specified in Article 2 are responsible for implementing this Circular.
2. During the implementation process, if there are difficulties or obstacles, they should be reported to the Ministry of Agriculture and Environment for timely review and resolution./.
DEPUTY MINISTER
DEPUTY MINISTER
(Signed)
Tran Quy Kien
원본 문서(PDF)
관계도
문서를 클릭하면 열립니다. 빨간 테두리＝효력을 변경하는 관계.