Terms of Reference HYDROGEOLOGICAL, GEOPHYSICAL INVESTIGATION AND SOCIO-ECONOMIC AND ENVIRONMENTAL ASSESMENT FOR BOREHOLE SITTING
Request for consultancy services (REF: BARI AND NUGAAL/OFDA – WASH/2018
Terms of Reference
HYDROGEOLOGICAL, GEOPHYSICAL INVESTIGATION AND SOCIO-ECONOMIC AND ENVIRONMENTAL ASSESMENT FOR BOREHOLE SITTING
Reference: SCI – Ground Water Consultancy
Area of Interest: Hydrogeological, geophysical investigation and Socio-Economic and Environmental Assestment for borehole sitting
Location: Camaan, Xubabays, Dharoor and Mareer ( Iskushuban district, Bari region) and Barweyn, Uusgure and Budunbuto ( Dangoroyo district, Nugaal region)
Position Type: Consultant/Firm
Duration: 1 month
Start date: DEC 2018
Save the Children has been making a difference in children’s lives in more than 120 countries. We are the world’s largest independent child rights organization, underpinned by a vision in a world in which every child attains the right to survival, protection, development and participation. Our mission to inspire breakthroughs in the way the world treats children, and to achieve immediate and lasting change in their lives.
To ensure delivery of this mission, Save the Children collaborates with local governments, multilaterals, grassroots, non-governmental organizations and others to identify and address supply and demand-related bottlenecks in both humanitarian and development contexts. Save the Children has been engaged in the WASH sector in Somali for more than 20 years.
In Bari and Nugaal regions water is extremely scarce. Most of the local populations in these regions use water from dams, Berkeds and earth pans. The high evaporation rates in the dams and, berkeds and earth pans coupled with the erratic rainfall and soils with poor water retention capacity makes earth pans an unreliable water source. Women and young children are at high risk of contracting water related diseases on a daily basis. In the 2017, cases of drought induced diarrhea have been reported due to use of contaminated water putting young children and expectant mothers at higher risk due to their low immunity. SC plans to target the drilling of two new borehole in Iskushuban and Dangoroyo districts where the assessment shows greatest need for permanent water sources. The five districts are convergence areas for domestic water and pasture during the dry season and has been badly hit by 2017 severe droughts. The districts are also a refuge area for people and livestock from Sool and Sanaag during the wet as well as dry season. The boreholes will act as contingency water points for the three districts. SC will hire a groundwater prospecting specialist to undertake borehole sitting studies in Iskushuban and Dangoroyo district in Bari and Nugaal regions. The key elements of the borehole sitting study are the thorough desk study, followed by fieldwork: hydrogeological reconnaissance in existing boreholes, and geophysical prospecting through 2D electric sounding (vertical and horizontal) and possibly 3D electric resistivity tomography. This survey will inform SC of the most probable locations for targeting the borehole drilling and availability and quantity of groundwater.
Prior to drilling, SC will make sure an appropriate preliminary study is carried out in order to identify the best possible location. This critical phase is called the borehole siting: without appropriate borehole siting through hydrogeological survey and groundwater prospecting, the likelihood to obtain a dry borehole is high. Save the Children will engage the best available consultancy to carry out a hydrogeological survey and groundwater prospecting through geophysical investigation in the selected locations where the new boreholes are to be constructed. The borehole siting will be done in the s first quarter of the project and a complete report will be produced. Based on the results of the hydro-geological survey report and the pump tests conducted after drilling, Save the Children’s WASH technical team will review what type of pump is most appropriate for the water point. A complete report shall be developed for each water point for internal and donor records. In order to ensure that the water provided meets standards allowed quality, Save the Children will conduct bacteriological water sample analysis on all newly constructed and rehabilitated water points. This is proposed to be done periodically; immediately after construction and at every 3 months throughout the span of the project to ensure that there is no fecal or chemical contamination posing danger to consumers. The report will be analyzed and any water point with traces of contamination will be analyzed and treated accordingly.
overall objectives OF THE HYDRO-GEOLOGICAL SURVEY
- Conduct hydrogeological and geophysical investigation for the optimal sitting of a drinking water borehole in Bari and Nugaal (Camaan, Xubabays, Dharoor and Mareer and Barweyn, Uusgure and Budunbuto villages. To conduct geophysical survey of underground water in the four above mentioned locations and identify the most suitable location for drilling of the new borehole in terms of getting sufficient amount of water with acceptable quality and affordable depths
- Review of knowledge people have with regard to the hydro-geological conditions in the area,
- Identify the positive and negative impacts of the proposed borehole and recommend appropriate mitigation measures considering potential impacts on natural and secondary environments and assessed potential on shortand long-term impacts.
- Investigate Social and ecological effects of groundwater development including loss of agricultural and grazing land, population resettlement.
- Examine effects on the existing water supply such as boreholes and shallow wells, including fluctuation of water levels and interference of the cone of depression in the boreholes.
- Potential environmental and social impacts by planned and unplanned (spontaneous) immigration into the area.
- Effects of existing and predicted land use on the functioning and longevity of the water supplies.
scope of THE WORK
The Consultant is expected to use both secondary and primary data in the exercise.Secondary data will involve desk study of available information/data on existing boreholes, drill logs, reports and maps while primary data will be obtained by carrying out field reconnaissance and measurements of existing boreholes and geophysical prospecting within the studied area using a combination of geophysical methods as below described.. : The outcome of the consultancy will be a detailed hydrogeological survey report giving details of the findings and recommendations.
Also the consultant is expected to coduct Socio-economic and environmental impact assessment To identify the positive and negative impacts of the proposed interventions and recommend appropriate mitigation measures considering potential impacts on natural and secondary environments and assessed potential on short and long-term impacts.
SURVEY APPROACHES REQUIRED:
The hydrogeological/geophysical investigations will be carried out in a multistep approach:
- Desk study: Review of existing data, topographical maps, satellite images, existing studies and borehole site investigations in the area, geological reports and maps (if available), borehole and surface water records, etc.
- Hydrogeological fieldwork: Detailed reconnaissance survey of project area. (GPS coordinates/P codes, water level measurements, condition of these boreholes, usage and performance, estimation of the hydraulic characteristics from existing well test and aquifer test, ), vertical geophysical prospecting at known boreholes for calibration purpose : measurement of the real resisitivities of geological formations based on the existing borehole logs.
- Geophysical measurements vertical and horizontal electric sounding, vertical electric 3D tomography, EM method and possibly seismic refraction method are recommended for this assignment.
- Analysis and interpretation of field data for selection of potential sites for drilling
- Presentation of the results to hydrogeologist/geologist experts from SC and Puntland State Agency for Water and Natural Resources (PASWEN) for validation of the best possible site
- Field validation of the site to ensure there is no obstacle for drilling (explaination and agreement with the community, no land tenure or future urban planning issues, access to drilling machine, risk of contamination, …)
The final report will be submitted to Save the children after signed off and approval from the ministry of water in Puntland State Agency for Water and Natural Resources (PASWEN). the report will be a comprehensive account of the whole of the Consultancy; it will review the existing literature and other relevant information, such as drilling logs, satellite images, etc. The report shall include all field data, interpretations and justifications, hydrogeological evaluations, conclusions and recommendations relating to the investigated areas. In addition, appropriate maps, diagrams and data plots shall be presented. Of considerable importance will be an objective assessment of the applicability and success of the methods applied
The outline table of contents of the final report will be as follows:
- Introduction, review of previous studies and environmental background hydrogeological information of the studied area, including history of groundwater depletion or known changes in quality : mineral content including unharmful –iron- and harmful -fluorides, nitrates…-; and toxic elements such as arsenic ; bacteriological pathogens.
- Geology and hydrogeology (incl. Inventory of positive and negative boreholes, aquifer characteristics –storage and hydraulic- and well characteristics –sustainable discharge rate- based on on available data., and water quality)
- Methods of investigations, including Geophysical Techniques
- Calibration of the geophysical instrument at known boreholes (yield, log) for the geophysic characterization of the geological formations, including the aquifer(s).
- Methods of investigations, including combination of geophysical methods.
- Geophysical prospecting on different sites.
- Detailed resistivity survey (Wenner & VES) and seismic refraction to delineate the productive aquifer
- Aquifer potential; sustainable yield & Water quality
- Interpretation and comparison of studied sites: aquifer and borehole potentials, Most suitable drilling site and justification , target aquifer(s) for drinking water production, mentioning assumptions, risks and risk management.
- proposed drilling method, with equipment characteristics (incl. estimation of the casing and screen positions)
- Simplified Environmental and societal impact of the drilling and required risks reduction measures
- Conclusion and recommendations
The consultant/firm is expected to deliver:
- An inception report presenting 1/ the steps and methodology for the assignment against the present Terms of Reference, and justifiying any difference or discard with the TOR ;
- the implementation plan and requirements for the site investigation. A brief note with the recommended sites selected for borehole reconnaissance and geophysical survey, for SC’s validation before the field deployment,
- The presentation of the field work, interpretations and conclusions to the SC and the water authorities.
- The final report
|ACTIVITY DESCRIPTION||Time Line|
|Secondary data collection, review of field documents on existing boreholes and studies, and analysis|
|Key informant interviews (face to face or remote)|
|Field work: Reconnaissance of existing boreholes, geophysical prospecting and final validation of the selected site|
|Presentation to SC and authorities, Reporting|
Save the Children seeks to invite qualified consultants/firms who meet the following requirements to submit their detailed narrative and financial proposal on how to undertake the assignment.
- Technical proposal on how the assignment will be conducted including methodologies, data analyses and interpretation, reports and schedules. ( List software to be used for analysis)
- Proven field technical and field experience of Consultant with Master’s degree in geology, hydrology, engineering geology, physical, or earth science, or in any related field and having good experience of working in this sector.
- Consultancies performed in the last 10 years especially with reference letters for each hydrogeological surveys consultancy
- Proof of availability of all the equipment’, personnel and ability to mobilize them on short notice (Include list of equipment, Brand/Manufacturer, CVs of the personnel) to perform the survey.
- Submit a detailed financial proposal including all professional fees, report costs and subsistence costs. Please note all costs must be broken down into details ( no lump sums, no contingencies etc)
The consultant/firm will be responsible for their own security; insurance while in the field and Save the Children will not be responsible for any injuries or damages incurred during the assignment. The costs submitted must be inclusive of all anticipated expenses.
SC will select the geophysical surveyor in based on their technical competence and experience.
MANDATORY SECURITY TRAINING
The consultant shall be expected to go through mandatory on-line security training and submit the certificate of completion to SC before the commencement of the task. Failure to deliver this will lead to an automatic disqualification. SC will advise on the security plan on appointment.
Interested parties must submit their applications by email referenced under title
HYDROGEOLOGICAL AND GEOPHYSICAL INVESTIGATION FOR BOREHOLE SITTING
Deadline for submission: 10/12/2018
Save the Children will consider applications from both individuals and firms. Applications shall clearly identify a team leader, who will be the sole responsible to deliver the outputs of the assignment.
Consultants are requested to submit a proposal with a cover letter and must mention their expected total remuneration for this assignment.
Applications should include:
- A proposal to the above Terms of Reference including methodology, schedule, budget.
- A financial offer including daily fees in US Dollars
- Up-to-date curriculum vitae(s) of the lead consultant and relevant team members,
- Description of available equipment for the assignment,
- Evidence of past experience in undertaking similar assignments (three most recent documents preferred) of similar works done,
- Three (3) references of previous assignments.
Only shortlisted applications will be contacted.
- Posted by: Somali Jobs Inc
- Company: Save the Children
- Location: Anywhere
- State: Nugal
- Job type: Contract/Consultancy
- Job category: Assestment/Investigation/Data Collecting/ Analaysing
- Tags: No Tags
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