Circular No. 10/2014/TT-BTNMT on technical guidelines for mapping groundwater quality at a scale of 1:100,000

CIRCULAR
Technical regulations for creating groundwater quality maps at a scale of 1:100,000

Pursuant to the Law on Water Resources No. 17/2012/QH13 dated June 21, 2012;

Pursuant to Decree No. 21/2013/NĐ-CP dated March 4, 2013, promulgated by the Government, stipulating the functions, tasks, powers, and organizational structure of the Ministry of Natural Resources and Environment;

Considering the proposal of the Director of the National Water Resources Management Department; the General Director of the National Center for Water Resources Planning and Investigation; the Head of the Science and Technology Department and the Head of the Legal Affairs Department;

The Minister of Natural Resources and Environment promulgates this Circular on technical regulations for creating groundwater quality maps at a scale of 1:100,000.

PART I
GENERAL PROVISIONS

Article 1. Scope of Regulation and Applicability

Article 1. This Circular specifies in detail the contents and technical procedures for creating groundwater quality maps and products of such maps at a scale of 1:100,000.

Article 2. This Circular applies to state management agencies for water resources, organizations and individuals who undertake the creation of groundwater quality maps at a scale of 1:100,000.

Article 2. Purpose of Creating Groundwater Quality Maps at a Scale of 1:100,000

Point 1. To reflect the results of groundwater resource investigation and assessment work at a scale of 1:100,000 or larger scales and other related studies on water quality.

Point 2. To serve state management of water resources and groundwater exploitation and utilization within key economic regions and inter-provincial river basins.

Point 3. To serve the preparation of groundwater resource planning within key economic regions and inter-provincial river basins, and socio-economic development planning at provincial and centrally-administered city levels.

Point 4. To meet the needs of information extraction for relevant sectors, localities, organizations, and individuals involved in groundwater exploitation and utilization activities.

Article 3. Base Maps for Creating Groundwater Quality Maps at a Scale of 1:100,000

Point 1. Groundwater quality maps at a scale of 1:100,000 are established based on topographic and hydrogeological base maps at the same scale or larger scales.

Point 2. The topographic base map is a topographic map at a scale of 1:100,000 (VN-2000 coordinate system) or a larger-scale map adjusted to a scale of 1:100,000.

Point 3. The hydrogeological base map used is a hydrogeological map at a scale of 1:100,000 (VN-2000 coordinate system) or a larger-scale map adjusted to a scale of 1:100,000.

Point 4. In cases where there are no existing hydrogeological maps in the research area, it is necessary to conduct surveys and create specialized hydrogeological maps with sufficient information to support the creation of groundwater quality maps.

Article 4. Mathematical Basis for Groundwater Quality Maps at a Scale of 1:100,000

Point 1. Groundwater quality maps at a scale of 1:100,000 are established in the VN-2000 National Geodetic Reference System and Coordinate System with characteristics: Global Ellipsoid WGS-84 suitable for Vietnam's territory; International UTM Plane Coordinate System; Zone 6.

Point 2. The projection system and central meridian will be implemented according to Circular No. 973/2001/TT-TCĐC dated June 20, 2001 of the Land Administration General Department guiding the application of the VN-2000 National Geodetic Reference System and Coordinate System.

Article 5. Technical Inspection and Product Acceptance Work

Technical inspection and product acceptance work shall be carried out in accordance with current regulations of the Ministry of Natural Resources and Environment.

Article 6. Types of products

1. Products of groundwater quality maps at a scale of 1:100,000 include:

a) Groundwater quality maps at a scale of 1:100,000 and cross-sections;

b) Groundwater quality maps for important aquifer layers or complexes at a scale of 1:200,000;

c) Appendices of data for map compilation: Books on chemical composition and groundwater quality statistics;

d) Special reports: Characteristics of groundwater quality.

2. The products are published in paper and digital formats.

Chapter II
CONTENT OF GROUNDWATER QUALITY MAPS AT A SCALE OF 1:100,000

Article 7. Base elements

1. Topographic base elements On groundwater quality maps at a scale of 1:100,000, the following base topographic elements must be represented:

a) Mathematical base layer: Map name, grid frame, and elements outside the frame;

b) Topographic layer: Contour lines, points and elevation values;

c) Hydrographic layer: Rivers, streams, lakes, ponds, canals, and their names;

d) Transportation layer: Roads, railways, bridges, and their names;

đ) Settlement layer: Concentrated residential areas, clusters of residents;

e) Administrative layer: For district level including the headquarters of district people's committees, city people's committees directly under provinces; for provincial level including the headquarters of provincial people's committees, centrally governed cities; names of administrative units: districts, counties, cities directly under provinces, provinces, centrally governed cities;

g) Boundary layer: District, county, city, provincial boundaries directly under provinces, watershed boundaries, border lines. Detailed topographic elements must comply with the provisions of geographic information standards issued by the Ministry of Natural Resources and Environment. Base topographic elements may be reduced by 15% to 25% to ensure priority representation of groundwater quality elements.

2. Hydrogeological base elements:

a) Distribution areas of water-bearing and non-water-bearing objects, including: Water-bearing structures, water-bearing rock formations or large water-bearing complexes, and non-water-bearing structures, formations, or complexes;

b) Water-bearing faults, predicted water-bearing faults, and faults with undetermined water-bearing conditions.

Article 8. Professional elements

Professional elements depicted on groundwater quality maps at a scale of 1:100,000 include:

1. Water quality for various uses.

2. Chemical composition of water at locations where analysis results are available.

3. Trace element composition and nitrate compounds.

4. Pollution zones, saltwater intrusion zones.

Chapter III
TECHNIQUES FOR REPRESENTING GROUNDWATER QUALITY MAPS AT A SCALE OF 1:100,000

Article 9. Principles for representing groundwater quality maps at a scale of 1:100,000

Groundwater quality maps at a scale of 1:100,000 must depict the contents of research results from investigations and assessments of groundwater resources at a scale of 1:100,000. The contents and information displayed on groundwater quality maps at a scale of 1:100,000 are based on the following principles:

1. Aquifers are divided according to aquifer layers, complexes, and non-aquifer formations, indicated by information such as the name of the complex or aquifer layer, distribution area, and distribution boundary.

2. Areas of water with different total mineralization suitable for different uses are represented by color.

3. Total mineralization (M) of aquifer layers or complexes at locations where analysis results are available is shown at representative points; the saline boundaries of covered complexes or aquifer layers are shown by lines of equal value M=1g/l.

4. Groundwater pollution indicators due to trace elements and nitrate compounds exceeding QCVN 09:2008/BTNMT standards are represented by area and point forms.

5. Chemical composition: Represent major ions by the dominant concentration symbols at each sampling investigation point and Kurlov formula on cross-sections.

6. Groundwater survey points such as drill holes, dug wells, and groundwater outcrop points are shown by symbols accompanied by identification numbers and symbols of the surveyed aquifer layers or complexes.

7. Faults: On groundwater quality maps at a scale of 1:100,000, water-bearing faults, predicted water-bearing faults, and faults with undetermined water-bearing conditions are represented by line forms.

8. Cross-sections: Cross-sections are established along characteristic directions such as perpendicular to structural orientation, along typical groundwater flow direction. The number of cross-section lines is selected according to specific mapping regions but must ensure comprehensive representation of regional information.

Article 10. Form of the Groundwater Quality Map at a Scale of 1:100,000

1. The name of the map, frame, and label shall be displayed according to the model prescribed in Appendix 3 attached hereto.

2. In cases where the map consists of multiple pieces, a piece assembly diagram shall be shown in the lower right corner of the map frame.

3. The map explanation is usually placed on the right side of the map frame, cross-sections are placed below the map frame. In some cases, the explanation may be placed within the map frame at an appropriate position or below the map frame.

4. Size of objects to be represented

On the groundwater quality map at a scale of 1:100,000, objects represented as areas must have a minimum actual width of 200 meters; objects represented as lines must have an actual length greater than or equal to 1,000 meters.

Article 11. Content to be Represented on the Groundwater Quality Map at a Scale of 1:100,000

1. Aquifer systems, aquifers, and non-aquifer layers:

a) Boundaries of primary aquifer systems or aquifers are continuous purple lines with a thickness of 0.4 mm, and boundaries of covered aquifer systems are dashed purple lines with a thickness of 0.7 mm, indicating the direction towards the distribution area accompanied by symbols for aquifer systems or aquifers.

b) Layers that prevent water flow or geological formations that do not contain water are represented by brown areas.

2. Distribution of water with different total mineralization levels:

a) Total mineralization value scale M (g/l):

- Fresh water: M < 1.0;

- Brackish water: 1.0 ≤ M < 3.0;

- Saline water: 3.0 ≤ M < 10.0;

- Briny water: M ≥ 10.0.

b) Representation of total mineralization values: For primary aquifer systems or aquifers on the map and cross-sections, the value of M will be represented by color according to the following scale:

- Areas of underground water with a value of M less than 1.0 g/l are represented by yellow;

- Areas of underground water with a value of M from 1.0 g/l to less than 3.0 g/l are represented by orange;

- Areas of underground water with a value of M from 3.0 g/l to less than 10.0 g/l are represented by light purple;

- Areas of underground water with a value of M equal to or greater than 10.0 g/l are represented by dark purple.

c) Boundaries of areas with different M values are represented by continuous green lines with a thickness of 0.7 mm.

3. Total mineralization of covered aquifer systems and aquifers

The total mineralization of covered aquifer systems and aquifers will be represented in two forms:

a) The boundary of salinity M = 1 g/l is represented by a dashed orange line with a thickness of 0.7 mm, accompanied by symbols for aquifer systems or aquifers, with the number of dashes corresponding to each aquifer system or aquifer, pointing towards the area with a value of M greater than 1 g/l;

b) The range of M values for aquifer systems or aquifers is represented by red hatch marks in columns at representative points.

4. Pollution indicators:

a) Areas of underground water showing pollution by trace elements and nitrate compounds exceeding the limit values of QCVN 09:2008/BTNMT are represented by areas with a brown-yellow dotted background symbol; boundaries of the same color, with a thickness of 0.3 mm, accompanied by symbols for aquifer systems or aquifers;

b) Points showing pollution of underground water due to pollution factors are represented by brown-yellow circles with a diameter of 3 mm at sampling points, accompanied by symbols for those factors and aquifer systems or aquifers in red, represented in fractional form.

5. Chemical composition

The chemical composition of water is represented at drilling holes, wells, and springs by symbols showing the dominant ion concentrations of major elements and Kurlov formulas on cross-sections.

6. Groundwater survey points:

a) Drilling holes: Represented by black circles with a diameter of 3 mm, accompanied by information: drilling hole number, symbol for the surveyed aquifer or aquifer system, total mineralization, and chemical composition;

b) Wells: Represented by black squares with a side length of 3 mm, accompanied by information: well number, symbol for the surveyed aquifer or aquifer system, total mineralization, and chemical composition;

c) Springs: Represented by black circles with a diameter of 3 mm, with arrows pointing upwards for spring outflows and downwards for spring inflows, accompanied by information: spring number, symbol for the surveyed aquifer or aquifer system, total mineralization, and chemical composition.

7. Faults: Represented by red lines with a thickness of 0.7 mm. Water-bearing faults are represented by continuous lines with crosses (×), predicted water-bearing faults are represented by dashed lines with dots (.), and faults with undetermined water-bearing conditions are represented by dashed lines.

8. Cross-sections: On cross-sections, the distribution of aquifers, aquifer systems, and non-aquifer layers is shown; areas of underground water with different total mineralization levels within each aquifer or aquifer system; chemical composition and Kurlov formulas at drilling holes, symbols for pollution parameters according to QCVN 09:2008/BTNMT.

9. The representation method and symbols on the map and explanations are detailed in Appendices 1 and 2 attached hereto.

Chapter IV
IMPLEMENTING PROVISIONS

Article 12. Implementation Organization

1. The Minister, Heads of Ministries equivalent to Ministries, Agencies under the Government, Chairpersons of Provincial People's Committees, Deputy Chairpersons of the National Center for Water Resources Planning and Investigation, Heads of Units under the Ministry, and related organizations and individuals are responsible for implementing this Circular.

2. The Department of Water Resources Management is responsible for guiding and inspecting the implementation of this Circular.

3. The limit values of water quality criteria specified in this Circular according to QCVN 09:2008/BTNMT. In case this QCVN is amended, supplemented, or replaced, the new limit values shall be applied.

Article 13. Effective Date

1. This Circular takes effect from April 7, 2014.

2. During the implementation process, if there are difficulties, it is recommended that agencies, organizations, and individuals promptly reflect them to the Ministry of Natural Resources and Environment for research, amendment, and supplementation./.