Afghanistan nationals: Topographic, Geotechnical and Hydrological Investigations Expert

Asian Development Bank (ADB)
Afghanistan
Position Type: 
Consultancy
Organization Type: 
International Organization
Experience Level: 
Mid-Level (5-7 Years)

EXPIRED

Please note: this job post has expired! To the best of our knowledge, this job is no longer available and this page remains here for archival purposes only.

Scope of Work

 
 

8. The site is located at the following coordinates: N 34º37’01.87”; E 69º41’55.09”. Exact details of
the boundaries coordinates will be provided prior to the commencement of works. The complete site will
be investigated by the Expert, considering an extension of 30 Ha marked green.

9. The scope of works is divided into three main components:
Component 1: Topographic survey
(i) Perform a topographic survey of the Project site including the adjoining areas and prepare a contour
map.
(ii) Installation of permanent survey control points in the project area.
(iii) Establishment of survey control points and network.
(iv) Detailed topographic survey of the sites using quality Electronic Total Stations (ETS) or DGPS in
RTK mode
(v) Data processing by using suitable survey software.

Component 2: Geotechnical survey:
(i) Conduct site reconnaissance, review site conditions and any other site related documentation and
provide appraisal of site’s geotechnical conditions.
(ii) Drilling of test pits and boreholes to determine site stratigraphy and to collect disturbed and
undisturbed soil for laboratory testing. 1 nos of bore will be sunk every 2 Jarib.
a. Light penetration test technology will be SPT.
b. Boring shall be carried out in accordance with the provision of latest editions of EC7/ IEC. Minimum
diameter of boring shall be 150mm.
(iii) Test pits of 1 nos per 2 Jarib with boreholes to 3.0 m depth and Two (2) borehole to 15 m depth.
(iv) Excavation of test pit where no consolidated rock formation or boulder is encountered specified
across the site. Trial pits depth shall be up to 3 m depth or depth of hard layer whichever is
encountered first.
a. Performance of field density tests by sand replacement method
b. Collection of block soil samples from test pits including their preservation in wooden box,
labelling, packing, storage & transportation to laboratory.
c. Collection of bulk soil samples (50 Kg). Includes labelling, packing, storage and transportation to
laboratory.
d. Collection of groundwater samples (if encountered)
e. The underground water table shall be recorded at each trial pit.
f. Lab testing of soil samples as per standard practice comprising of:
• California bearing ratio (CBR) of every alternate pit sample
• Modified proctor of every alternate pit sample
• Swell pressure of every alternate pit sample. Thermal conductivity tests
(v) The depth of underground water table shall be measured in all the boreholes. Before taking the water
table readings, the water table in the borehole shall be allowed to stabilize after depressing the water
level adequately by bailing. The water table reading shall be recorded after 24 hours of completion of
borehole.
(vi) Testing selected soil or rock and groundwater samples in the laboratory to determine pertinent
index and engineering properties of the soils or rocks.
(vii) Analysing all field and laboratory data to develop engineering recommendations for foundation
design and construction.
(viii) A detailed drawing showing exact test locations and co-ordinates shall be furnished to the Client
(ix) Recording water table in the boreholes
(x) Laboratory tests on soil and water samples collected from boreholes.
(xi) Electrical Resistivity test 8 nos (2 each in either N-S-E-W direction).
(xii) Standard Penetration Tests:
a. Standard penetration tests (‘SPT’) shall be conducted at every change of the strata of soil.
b. The collected record for each sample location needs to be presented in tabular and graphical form.
(xiii) Disturbed Soil Samples:
a. Disturbed soil samples shall be collected at every change of strata. Identification labels indicating
depth, borehole number and visual soil classification shall be affixed on the containers.
b. The sampling to be done through use of slotted rod which shall complement the ramming tip. The
location should be near or at the same point where penetration test is performed (at max. depth).
(xiv) Undisturbed Soil Samples:
a. Undisturbed samples (150mm dia.) shall be collected at every change of stratum. In soft deposits,
piston sampler shall be used to collect UDS. Quoted rates shall include transport of samples to the
laboratory.
b. The boreholes shall be backfilled with sand and compacted properly by pouring water after completion
of boring/samples collection and observation of Ground Water Table.
(xv) Electrical Resistivity Tests:
a. Perform field electrical resistivity tests to provide data for soils at each specified location for
depths of 1, 2, 3, 4, 6 meters below the grade and in both the North-South and East-West directions.
b. Perform electrical resistivity tests in accordance with EC7/ latest IEC codes. For field-testing,
water shall be used to wet the pin locations before each measurement to ensure good contact between the
pins and the soils.
(xvi) Laboratory Tests:
a. After collecting disturbed and undisturbed samples from different boreholes at different depths a
laboratory test schedule shall be prepared and submitted to Owner/Owner’s representative for review.
b. Adequate number of the following tests shall be conducted to clearly determine the mechanical
strength and compressibility characteristics of each strata of soil encountered. All tests on rock and
soil samples shall confirm to IEC codes.
(xvii) Grain Size Distribution:
a. Wherever applicable both the sieve & hydrometer analysis shall be conducted to indicate complete
range of grain sizes of soil samples tested.
(xviii) Chemical Tests:
a. Chemical tests shall be conducted on soils & water samples as per relevant IEC codes to report the
following:
• pH
• Chlorides in ppm & percentage
• Sulphates in ppm and percentage and expressed as SO3 & SO4 California bearing ratio (CBR) of every
alternate pit sample

Component 3: Hydrological survey
(i) Water Table Map
(ii) Water flow direction
(iii) Identification of potential water zones.
(iv) Location for setting up suitable location for tube wells (if required)
(v) Possibility of channeling water into the site from nearby reservoirs
(vi) Water quality analysis.
(vii) Suggestion for further treatment of water, if any.

10. The Expert will be responsible for the coordination with experienced firms and/or individual experts
to conduct the required site studies and laboratory tests. Provisional sums / Lump sum will be allocated
to carry out these tests, and the management of the subcontractors will also be under the responsibility
of the Expert.

11. Safety and security requirements and costs to develop the required field studies shall be allocated
by the Expert. The Expert will guarantee that the required protection and prevention actions are
implemented for the field studies.

Detailed Tasks and/or Expected Output

 
 

D. Expected Output

12. The Final Report for the required studies shall include but not limited to the following:
(i) A plot plan showing all test locations with respect to reference bench mark. The co-ordinates and
RL's of test locations shall be given in a tabular form in the report.
(ii) Contour map of the whole plot.
(iii) Topographic plan of project site at 1:500 scale and 0.5m contour interval in soft form.
(iv) Survey Report including methodology, calculation sheets of control survey, and description sheets
of control points.
(v) Production of topographic survey drawings in CAD format at 1:500 scale.
(vi) Submission of drawings and brief survey report, including methodology, survey control points
summaries, control points description sheets. The topography report should include the quantity of
cutting/filling of earth required, if any.
(vii) General geological information of the region.
(viii) Character and genesis of soil. (Type of soil and is characteristics varying depth of collected
samples)
(ix) Procedure of investigation and method of various testing adopted.
(x) Detailed bore logs indicating co-ordinates, reduced level, ground water table etc., sub soil
profiles along various sections indicating boreholes nos., depth wise in-situ test results like SPT and
other lab test results etc.
(xi) All field and laboratory test results shall be plotted against depth in the bore log and also in
tabular form.
(xii) Summary of results obtained from various tests and their interpretation to evaluate various soil
parameters along with all literature backup.
(xiii) A set of longitudinal and transverse soil profile connecting various boreholes shall be presented
in order to show the variation of soil stratum.
(xiv) Recommendation regarding ground water table fluctuation and design ground water table to be
considered for design of foundations.
(xv) Design soil profiles with various design parameters shall be plotted with depth duly considering
various field and laboratory test results for bearing capacity and tank settlement calculation.
(xvi) Determination of ramming depth - using Eurocode 7-1, DIN 1054 as per EC7 and calculations per
guidelines ZTV- Lsw 88 and ZTV – Lsw 06 or any other International Standard for determination of length
of poles
(xvii) Determination of depth for screw foundation as per EC7 or International standards
(xviii) Determination of details for foundations through predrilling and concrete pouring method as per
EC7 or International standards. If not given in the standards and required to perform calculations, the
reference loads and along with steel profile (C-channel or similar) details shall be provided by
Employer to Expert.
(xix) General Notes / recommendations on above foundations / site civil works with respect to ground
excavatability, gradability and roads shall be given by geotechnical expert firm.
(xx) Recommendation for pipe supports and pavement shall be included.
(xxi) Comments on chemical nature of ground water and soil with due regard to potential deleterious
effect on concrete and steel and firm recommendations on protective measures. Also, remedial measures
for any sulphate attack or detrimental acidic conditions shall be dealt in detail giving clear practical
recommendations.
(xxii) Recommendation related to site preparation including classification, placement and compaction of
fill materials required to bring the general site level of final grade level if so required.
Recommendations regarding excavation, stable slopes for excavation, dewatering and method of dewatering
if warranted.
(xxiii) Recommended laboratory C.B.R values for filled up soil for both soaked and unsoaked conditions.
The compaction characteristics of soils proposed to be used for filling below roads, pavements and
backfilling of foundations must be furnished.
(xxiv) Recommendation of soil resistivity to be considered for design purpose.
(xxv) Recommendations for special soil conditions such as expansive, collapsible, highly compressible
etc.
(xxvi) Recommendation for ground improvement and type of ground improvement techniques applicable if
any.
(xxvii) Assessment of seismic hazard and liquefaction shall be carried out and reported.
(xxviii) Analysis of tank foundations under short term loads (hydro-test), long term loads and seismic
loads shall be made.
(xxix) All calculations, recommended design parameters and measurements shall be reported in SI units.
(xxx) Flood risk assessment of the site.
(xxxi) All recommendations furnished in the report shall be supported by detailed back-up calculations.
Extract of relevant parts of the references/literature used in firming up the recommendation shall be
appended in the Geotechnical report.

13. The Expert will submit the following reports and project documents in English. All deliverables
shall be submitted in a soft copy and a hard copy

Minimum Qualification Requirements

 
 

E. Minimum Qualification Requirements

14. The expert will be allocated in Afghanistan and should preferably have a bachelor or higher degree
in engineering or related fields with at least 8 years of relevant experience in geotechnical,
topographic, or hydrological surveys in accordance with international best practices. Previous
experience in DABS projects is highly desirable. The Expert will provide inputs and assistance to the
experts involved in the project, being responsible of the supervision of tests, analysis of results and
preparation of reports.

A. Background

1. Lack of domestic generation remains the most critical challenge for energy security in Afghanistan.
With the completion of the highly successful TA8808: Renewable Energy Development and the approval of
the 20 MW Naghlu Solar Power Project under the multitranche financing facility (MFF) grant to the
Islamic Republic of Afghanistan for the Energy Supply Improvement Investment Program Tranche 3 in 2017,
the country is on track to achieve its domestic renewable energy targets.

2. TA8808, among other outputs, developed the Afghanistan Renewable Energy Roadmap and several pre-
feasibility studies. Building on the initial due diligence conducted under the TA, individual
consultants are needed to develop the feasibility studies and project designs, prepare technical
specifications and drawings, draft the bidding documents and contracts, and assist DABS in the
procurement.

3. Building on this momentum, the proposed Tranche 6 aims to install a second on-grid utility scale
plant in Surobi district. Afghanistan Independent Land Authority (Arazi), has allocated a proposed 30
Hectares site for the development of the project. The Executing Agency (EA) is Da Afghanistan Breshna
Sherkat (DABS).

B. Objective

4. The proposed study aims to conduct the required Geotechnical, Topographic and Hydrological
Investigations to include a full report as part of the Bidding Documents of the second on-grid utility
scale Solar Power plant in Surobi.

5. The full report will include but will not be limited to: soil characterization, soil resistivity,
chemical tests, topographic and hydrology survey.

6. The full report prepared by the Expert shall assist Consultants and Contractors during Project Design
stage. It must contain the required information to:
• Give recommendations for the foundations of the PV racking structures, buildings, equipment, roads and
trenching for underground cable installations.
• Undertake flood risk assessment of the site and investigate the schemes for provision of water on-site
for the duration of the project.

7. As a reference for the Individual Expert, piling works of the PV racking structures and equipment,
except of using shallow and ballasted foundations, include the following procedures:
• Ramming of steel profile directly in ground
• Screw foundations
• Steel piles installed in Pre-drilled holes filled with filler material or concrete
• Auger piles.