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Topographical Survey Methodology | Types

1.         PURPOSE

 

1.1      This engineering specification establishes the elements required for the preparation of drawings for any parcel of land/property.

 

 

2.         scope

 

2.1       This specification applies to any parcel of land/property purchased or leased by Air Products Gases Group Europe.

 

2.2      Information (for example, drawings or reports) offered and supplied shall be in full compliance with this specification. Deviations are not permitted without the written approval of Air Products.

 

2.3       The supplier’s scope of supply includes the topographical survey and survey drawings.

 

2.4       The completed information/documentation shall remain the sole property and copyright of Air Products and shall not be used for any other purpose without the written approval of Air Products.

 

 

3.         related documents

 

3.1       Air Products Engineering Documents

 

4ECS-0055       Geophysical Survey

 

 

  1. SITE DESCRIPTION

 

4.1      The following descriptions will be advised:

 

               Location

Address/Contact

               Access

Site Rules and Regulations

 

 

  1. AUTHORITY REQUIREMENTS

 

5.1      The contractor shall be deemed to have acquainted himself with the current requirements of all relevant authorities, laws, codes of practice, and standards as are applicable to these works.

 

 

  1. PERMANENT SURVEYS: GENERAL

 

6.1      All surveys shall relate all information and features to at least two permanent survey stations and shall be linked where possible to the National Survey grid.

 

6.2      The surveys shall include clear item descriptions for each feature. Units shall be in millimetres, but when existing site data and coordinates are in other units, these shall be stated and shall be linked where possible to the National Survey grid.

 

  1. PERMANENT SURVEY STATIONS

 

7.1      Survey stations shall be located and constructed in positions that are within a maximum of 50 m from the site, so that they remain throughout any construction work proposed on the facility. Care shall be taken to locate them on rock, concrete, or similar semi-permanent hard areas clear of all obstructions and clearly visible from one to the other. Their location shall be clearly indicated on the drawing.

 

7.2      Survey stations shall consist of a proprietary permanent marker system which is suitable for the location and ground conditions. For hard surfaces, a nail or equivalent shall be driven or fixed firmly into the surface. In this latter case, the physical location shall be clearly marked with appropriate bright coloured permanent paint surrounding the point. All types of markers shall be of suitable quality/durability and shall not form a trip hazard.

 

7.3      The distance between each station, both horizontal and vertical, shall be established to within an accuracy of 3 mm.

 

7.4      Each station shall be located relative to the existing site grid coordinates and elevations or to the national datum and grid reference, as specified on the drawing to within an accuracy of 5 mm.

 

 

  1. ABOVE GROUND SURVEY

 

8.1      The survey shall contain, but not be limited to, the following information:

 

               All adjoining properties and names of owners, together with fence or boundary ownership, and the former use of the plot. Description of the type of fence/wall/hedge or marking of boundary as required.

 

               The location and name of two or more locating roads giving access to the plot.

 

               The location of railway lines or waterways within 100 metres of the property boundary.

 

               The presence of any coal mining operations or underground workings within 1 kilometre of the site (see also 4ECS-0055).

 

               Indication of any known concentrations of toxic materials within the boundary (see also
4ECS-0055).

 

               The location and size of drains, both foul and surface outside the property, together with the nearest fire hydrant, water services, gas main, electrical supply, and telecommunications network.

 

 

  1. SURVEY OF UNDERGROUND SERVICES AND CABLES

 

9.1      A survey of all underground features, using radio/electronic/electromagnetic equipment specially designed for the purpose, shall be used to locate (without disturbing the ground) all underground metal features, pipes, and underground cables. The underground features shall include all of the following:

 

               Location, direction of flow, invert levels at manholes, and size of drains both foul and surface

               Location, depth, and size of potable water

               Location, depth, and size of electrical supply

               Location, depth, and size of gas supply

               Location and depth of telecommunications network connection point

               The building line restrictions and rights of way or other legal or planning restrictions on the use of the land including above or below ground permanent easements

 

  1. SURVEY OF OTHER FEATURES

 

10.1       When buildings are included within the site, the survey shall also contain the following:

 

10.1.1    The measurement, location, extent, and construction details shall be shown. This also applies to car parking hard standing, illumination, plant/machinery foundations, or if the site has been previously demolished and buildings removed, the location of old foundations or areas of possible contamination. In all cases, the uses of these buildings/areas shall be established.

 

10.1.2    The survey should, when possible, be linked to the national survey grid system.

 

10.1.3    Dependent on plot size, surveys shall be drawn to a scale of 1:200, 1:500, or 1:1250.

 

 

  1. DRAWINGS

 

11.1       Location Drawing shall be drawn to a scale of 1:1250.

 

11.2       Detail drawings shall be accurately drawn to a scale of 1:200.

 

11.3       They shall show all the features outlined and with clear description and all other information requested or obtained from the survey.

 

11.4       The survey shall produce sufficient data to enable, from the fixed datum, a closed survey eliminating all discrepancies.

 

11.5       When the location of the nearest permanent ordnance survey station, or other station, is off the site to be surveyed, its location shall be indicated by additional descriptions and sketches at appropriate scales.

 

11.6       True north shall be indicated. When an existing reference system is in use, the relation of this system to true north shall be given.

 

11.7       All dimensions and levels shall be in metric units.

 

11.8       All information shall be in the English language.

 

11.9       These drawings shall be supplied in AutoCAD format or compatible.

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