Detailed topographic maps of the surface within the work areas will be prepared at scales of 1:2,000 for detailed areas and 1:1,000 and 1:500, for setting out the locations of trenches, cuts, drill holes, and road alignments in the field.

Topographic and geodetic works are carried out in accordance with the “Instruction on Topographic and Geodetic Support of Geological Exploration Works” (1984). Operational topographic and geodetic control is provided using GPS receivers with centimeter-level positioning accuracy.

The topographic and geodetic coverage of the work area is generally represented by state-published topographic maps at scales of 1:100,000 and 1:50,000. State geodetic network control points are generally available.

Determination of Plan Coordinates

The plan coordinates of geological exploration observation points will be determined using:

  • triangulation networks;

  • angular, linear, and combined linear-angular resection;

  • the polar method.

The elevations of geological exploration observation points will be determined by trigonometric leveling.

Angular measurements will be performed using a total station with 2-second accuracy.

Point coordinates will either be obtained graphically from plans or calculated based on geodetic measurements. Based on the field and office processing of coordinate and elevation measurements, a catalog of coordinates and elevations will be compiled.

Office Processing of Topographic Data

Office-based topographic processing will include:

  • calculation of coordinates and elevations of survey control points;

  • transformation of the coordinates of all initial control points into a unified coordinate system agreed upon in accordance with the technical specifications;

  • creation of digital electronic versions of topographic plans at the required scales;

  • preparation of the relevant section of the report on the completed topographic and geodetic works.

All geodetic measurements will be processed in a unified coordinate system directly at the work site. Adjustment of triangulation networks used to establish the survey control network will be performed using specialized computer software.

The coordinates and elevations of individual survey control points will be calculated using RGS, Credo-Dat, or, where applicable, the MK-52 programmable calculator, based on generally accepted formulas.

The transformation of previously established geodetic networks into a unified network, in accordance with the requirements of the technical specifications, will be carried out using ArcGIS and GPS software. A consolidated catalog of coordinates and elevations will be prepared for all new and previously established survey control points.

Digital Topographic Plans

Electronic versions of topographic plans at the required scales will be created using Easy Trace and ArcGIS software.

The output formats will include:

  • Vector formats: *.shp, *.mdx, *.sdx, with data organized by layers (terrain, hydrography, mine workings, contours, etc.);

  • Raster formats: *.tif, *.jpg for hard-copy materials.

To create an integrated digital environment, terrain and contour data will be consolidated along the boundaries of survey areas at different scales, as well as with data from previous surveys.

The final stage will consist of preparing a technical report covering all types and volumes of completed topographic and geodetic works.

Scope of Topographic and Geodetic Works

To support geological prospecting activities, the following topographic and geodetic works will be performed:

  1. Development of a working survey control network (micro-triangulation), including survey control points and access routes to mine workings — 100 points.

  2. Office processing of micro-triangulation data.

  3. Tacheometric survey at a scale of 1:2,000, with contour intervals of 2.0 m, to support geological mapping and establish the coordinates of geological observation points. Difficulty category — 5.

  4. Preparation of a topographic plan at a scale of 1:2,000.

  5. Surveying and positioning of trenches using three or more control points.