Expertise: hydrogeology
Expertise Group: Biological Sciences & Ecology
Consultant Source: International
TOR Keywords: hydrogeology, sampling, bore holes
Objective and Purpose of the Assignment
The Integrated Urban Services and Resilient Improvement Project (IUSRIP) has been established to improve
the three urban services of water supply, sanitation, and solid waste management in the Republic of the
Marshall Islands (RMI). One component of the IUSRIP required the construction of a desalination plant in
Majuro as part of building resilience to climate change in that island. The desalination plant shall be
a Sea Water Reverse Osmosis (SWRO) plant and shall be constructed close to the shore of Majuro. It is
proposed to use saline bore water drawn from bore(s) located in the vicinity of the beach to supply the
plant. This assignment is to gain an understanding of the availability of bore water leading to the
concept design and specification of a bore field to supply the desalination plant.
The SWRO desalination plant will initially supply 1,500 kl/d but may be expanded in the future to supply
2,500 kl/d at some future date. The minimum plant recovery rate will be 40% meaning that some 3,750 kl/d
(44 l/s) will initially be required to feed the desalination plant potentially expanding to 6,250 kl/d
(72 l/s) at some future date. The brine will be discharged to the ocean via an outfall.
Scope of Work
The purpose of this role is to lead the undertaking of a hydrogeological study to determine the
suitability of using groundwater as the raw water source for a 1,500 kl/d SWRO desalination plant to be
constructed in the vicinity the Marshall Islands High School,* Majuro and to assist in the preparation
of requirements and specifications for the subsequent groundwater extraction works. The study shall also
consider the possible future expansion of the SWRO desalination plant to 2,500 kl/d as some future date,
although such an expansion does not form part of this project.
*Note that final project site may change; to be confirmed with the project executing and implementing
agencies.
Detailed Tasks and/or Expected Output
The duties of the position are:
• Throughout the drilling of the bores liaise with (a) the MWSC, (b) the drilling contractor engaged
under Grant 6028 and (c) the water sampling and testing specialist and coordinate their activities
regarding this assignment.
• Inspect the transport and setting up of the drilling rig onsite and the provision for drilling waste
disposal and comment as appropriate.
• Inspect the drilling equipment and comment as appropriate.
• As applicable review the drilling methodology and comment as appropriate.
• Inspect the drilling of the two bores (test and monitoring) and confirm the recording of the bore logs
by the Contractor.
• Confirm with the Contractor the optimum depth of the planned production bores.
• Inspect the step test (at least four steps required) and continuous flow test of the bores and confirm
the recording of the results by the Contractor.
• Discuss the results with the Contractor and analyse/confirm the Contractor’s analysis of the data and
(a) confirm the sustainability of the design flow from the bore and (b) the recovery time for the bores.
Comment on the diameter of the bore as appropriate.
• Facilitate the collection of water quality testing samples by the water sampling and testing
specialist.
• Collect the tide gauge data from the Marshall Islands Weather Service and correlate the change in sea
level with the change in water level in the monitoring bore over a full tidal cycle following the
completion of the testing (post pumping).
• Inspect the capping of the bores, the removal of any waste material and the removal of the drilling
equipment from site.
• Prepare a report containing the following:
o The bore logs
o The results of the pump test and the flow test and comment on the proposed design flow.
o Comment on the required spacing between the proposed four bores (3 production, 1 monitoring).
o Comment on the relationship between the tide level and the bore water level
• Prepare a specification for the proposed bores suitable for including in a bidding document.
• Other related tasks that may be assigned as required.
Reports
The consultant shall prepare and submit the following documents:
• Progress and final reports of project activities and outputs as per terms of reference.
Programme
The consultant shall advise the Project Implementation Unit of the likely consultancy completion date
following the first field visit (given the dependency on mobilising a drilling contractor). The
consultant shall submit its final report as soon as practical but at least within four months of being
awarded the assignment.
Minimum Qualification Requirements
Qualification:
• Tertiary qualification in hydrogeology or similar.
Experience:
• At least 10 years field experience as a hydrogeologist.
• Has undertaken at least three hydrogeological studies in Pacific Islands.
• Has overseen at least one hydrogeological study involving the construction of test or production bores
in coral islands.
• Has overseen at least once the testing of bore water for a range of water quality parameters, similar
to this assignment.
Minimum General Experience: 10 Years
Minimum Specific Experience (relevant to assignment): 7 Years
