19bY7025Q0020_SOW_WaterDrilling.pdf

Embassy of the United States of America

Bujumbura, Burundi

STATEMENT OF WORK

For

WATER WELL DRILLING PROJECT AT EMB02

June 30, 2025

Statement of Work for Water Well Drilling project at EMB02 U.S. Embassy Burundi, Bujumbura

1.0 SUMMARY

The US Embassy in Bujumbura, Burundi, has requirements for drilling a new well to include purchasing and installing the well pump and connecting the well to the bulk water supply fill station that will be located at Embassy 02 Compound outside perimeter wall.

The objective is to have a fully functioning water well that will supply water to the rest of

Embassy residential areas using water distribution truck, the truck must be able to connect easily to bulk supply filling station. In accordance with the terms and conditions set forth below, the Contractor will furnish all supervision, labor, management, facilities, supplies, equipment and material, and all required services necessary for the performance of the work. The Contractor will provide the required services to the U.S. Government as described in the requirements below.

2.0 REQUIREMENTS AND DESCRIPTION OF WORK

2.1 Continuous Verified Yield of 48-120 Cubic Meters per Day (CMD). The contractor shall design and install a complete well system with sufficient integration of well components and other systems to ensure all components are matched and capable of delivering, conveying, and treating (as required) the required continuous yield from the well.

2.2 Investigations and Analysis. The contractor will investigate and analyze geotechnical, geophysical, and groundwater hydrology characteristics required to plan, locate, and construct a complete well system that will provide the required continuous yield.

2.3 Well Location Requirements. The well must be protected from the pollution of non-sanitary surroundings and should be located at the minimum distances from the structures or topographic features identified in Table 1 below:

Table 1. Minimum Well Location Distances Current well location distances Structure or Topographic Feature Minimum distance

(M)

Distance (M)

Building Foundation – Non-Treated 3 17

Building Foundation with Termite Treatment 15 17

Residential Sewer Line 15 16

Wastewater Treatment Plant or Sewage Lift Station 30 N/A

Individual Septic Tanks 15 39

Septic Tank Drain fields 30 66

Underground Fuel Storage Tanks 30 N/A

Table 1. Minimum Well Location Distances Current well location distances Structure or Topographic Feature Minimum distance

(M)

Distance (M)

Cemetery 30 N/A

Non-Potable Water Well 30 N/A

Property Line 15 30

Storm Water Detention Basin or Infiltration Beds 15 40

2.4 Well site for the CMR and DCMR are shown in Attachment # 1

2.5 Pump Specifications

The contractor shall provide a pump with footing and a protective screen sized to prevent the introduction of sand or silt into the suction line. The pump motor shall be a three-phase, 10 HP, 400 V, or higher pump. Capable of pumping water at a head pressure of

145 psi at a minimum of 40 m above the ground surface. The following model or COR approved alternate is acceptable:

MFR: Grundfos Electric

Model #: SP14-25

Electrical spec: 16A,400V ac up to 19Amps in all three phases.

The Embassy reserves the right to reject any pump that does not meet the specifications provided above.

2.6 Well Specifications

2.6.1 Well depth: 80m to 120m depending on the soil topology.

2.6.2 Diameter: 6inch [Outer Diameter.]

2.6.3 Pipe type: [Unplasticized polyvinyl chloride Casing (ASTM F480 and NSF 14, Schedule 40) or as approved by COR]

2.6.4 Optimum Pumping Rate:2 to 5 m3/h

2.6.5 Typical Well Section: 65.15m Depth of Casing, 14.85m Depth of Screen, 80m to

120m Depth of Sump depending on soil topology.

2.6.6 Typical Water Elevation: 80m to 120m Distance below the surface depending on soil topology.

2.6.7 Screen Material: Type 304 Stainless steel or as approved by COR.

2.7 The contractor shall perform the following services:

2.7.1 Drill well at 80m to 120m depth depending on soil topology and 10-inch width (diameter).

2.7.2 Preparation of UPVC and PN16 pipes infiltration and placement of filter element.

The contractor is responsible for all materials.

2.7.3 Development of drilling via Development by air lift-normally rotary drilled & DTH drilled Method. Complete drilling to an estimated depth of usable groundwater and estimate safe yield for well prior to completion. Develop wells to maximum yield per meter (foot) of drawdown.

2.7.4 Fill annular space from top to bottom with concrete grout and provide permanent casing with temporary well cap. The top of the casing should be 900 mm (36 inches) above the finished grade.

2.7.5 Finalization of the project with concrete cover at the annular space extending at least one meter from well casing. Provide casing vent that extends above the top of the well casing, with pipe turned down and capped with mesh to prevent insects from entering well. Seal space between well casing and concrete with silicone sealant.

2.7.6 Connection of the well water pipe with the water distribution pipe up to the fill station that will be located outside the perimeter – nearest filling point will be identified during the site visit.

2.7.7 Construct a bulk water supply filling station outside the perimeter wall for water supply truck.

2.7.8 Purchase of 1 pump, Grundfos,15m3/h, 3 Phase with 2584 mm of 4x4mm2 electric wire and installation accessories

2.7.9 Install the pump and test for plumbness and alignment per AWWA A100. Electrical connection will be made by the US embassy

2.7.10 Conduct final pumping tests after wells have been constructed, cleaned, and tested for plumbness and alignment.

2.7.11 Disinfection, testing, and measuring the flow of the well.

2.7.11.1 Upon completion, the well shall be disinfected in

accordance with current AWWA (American Water Works

Association) standards (AWWA C654 -13) for well disinfection except that the disinfectant shall remain in the well for at least twenty-four hours.

2.7.11.2 Before placing the well in service, the water containing the disinfectant shall be flushed from the well. Then samples of water shall be collected and submitted for microbiological analysis until three successive daily raw water samples are free of coliform organisms.

2.7.11.3 A complete physical and chemical analysis of the water produced from a new well must be made after 36 hours of continuous pumping at the design withdrawal rate. The samples should be submitted to a certified laboratory for analyses. Water quality tests shall include those parameters and methods shown in Table 2 below.

2.7.12 Pumphouse Structure: See the drawings in the Attachment #2.

2.7.12.1 Remove foundation excavation soil for pumphouse

construction.

2.7.12.2 Concreted Pad

2.7.12.2.1 A new reinforced concrete pad shall be constructed for the new well.

2.7.12.2.2 Concrete pad dimensions of the well house's footprint shall be 3-meter x 3-meter slab on grade 50cm thick with specified rebar reinforcement.

2.7.12.2.3 The Contractor shall provide structural computations for the concrete pad design, considering the following loads and actions:

• Liquid load

• Wind load

• Flotation

• Earthquake, to meet seismic zone-3 requirements

• Ground movements

• Structural loads

2.7.12.2.4 Concrete shall be batched at a concrete plant and

delivered by a concrete truck with a mixing drum.

2.7.12.2.5 At a minimum, the pad shall be cast in place concrete, 20-inch thick, with a single layer of #10 rebar (1 1/8-inches) on 18-inch centers each way located in the center of the slab. The new, extended slab rebar shall be dowelled into the existing slab, with a 6-inch of crushed stone under the slab for drainage. The concrete should be air-entrained (for workability) to a working pressure of 20 MPA and finished to match the existing slab. The sub-base should be prepared to eliminate any areas with a bearing capacity of less than 10 KPA or alternately proof roll the area with a loaded 9000kg 10 wheel or similar truck and over excavate, replace, and compact the sub-base. The Contractor shall recommend any additional work deemed necessary to expand the pad and tie into the existing pad, subject to

COR approval.

2.7.12.3 Walls shall be made of concrete block. Plaster and mortar shall cover walls on the inside and outside of the structure.

2.7.12.4 Concrete flooring shall be smooth

2.7.12.5 Entrance door shall be steel that is 2m tall x 1m wide x

2mm thick, gasket seal (all sides) and stainless-steel hinges, Aluminum vent with a screen on top of the door with

Italian Yale padlock with deadbolt

2.7.12.6 Power to the well and associated electrical works

1) Sub-panel with a 4-wire service near utility room

(determined during the site visit)

2) Well pump house sub panel with a 4-wire service

3) Exterior light and light switch

4) Interior light and light switch

5) Interior 220–230-volt GFI duplex outlet

6) Well pump house sub panel with a 4-wire service

7) The sub-panel service should be larger than the required circuit for the well pump. This way, the sub-panel may provide a circuit for the well and have additional capacity for lighting and freeze protection or other accessories.

2.7.12.7 Roof shall have facia board with galvanized corrugated sheets BG 28 repainted

2.7.13 Clean work site area after completion of the work each day

2.7.14 Restore work site to pre-construction conditions

2.7.15 Monitor any discrepancies and corrective action

3.0 DELIVERABLES

3.1 Water Well (Borehole) with the specified casing 8-inch inside diameter PVC meeting

ASTM standards for wall thickness.

3.2 Pump meeting Lorentz variable frequency or better capable of utilizing city power AC or inverted PV solar power with appropriate PV panels to meet water demand specified in this SOW and maintain 40psi.

3.3 Control Panel - The pump must be operated in both Manual and AUTO Mode and be provided with adequate protection such as level probes, pressure switch, flow switch and backflow preventers to prevent the submersible pump from operating in the absence of water to ensure its long life and avoid costly maintenance.

3.4 90mm supply pipe to the outside filling point or port station to be installed with sand filter (this will be provided with Post) to filter sand from being filled in to the water supply truck.

3.5 Install sample port/valve if necessary. Exact sample port/valve location shall be determined by contractors on a pre-bid walk through.

3.6 If possible, the control panel made by pump manufacturer can be installed with signal communication to float switch in existing water storage tank also controlling water supply to the EMB02 residence. The water tank must be 90% full before the pump can be used to supply water to the outside filling port station.

3.7 Pump house that encapsulates the new well head built on a 3-meter x 3-meter slab on grade 50cm thick with specified rebar reinforcement. Pumphouse specifications are detailed in section 2.7.11 in this SOW.

3.8 Clean-up site, remove all spoils from drill location, re-landscape the site back to its original condition, plant trees and grass as necessary.

3.9 Provide a comprehensive one-year warranty on all work done to meet specifications and performance set forth in this statement of work.

3.10 Provide water quality testing analysis as per Table 2 below.

1 Includes constituents and contaminants identified in EPA 570/9-75-001 (Manual of

Water Well Construction). Additional Safe Drinking Water Act regulated parameters should be tested if water is intended to be used for human consumption as identified in

EPA 816-F-09-004 (per current OBO specifications, i.e. SECTION 332100 - WATER

SUPPLY WELLS, January 2012).2 Field Measurement

Table 2. Basic Water Quality Analyses for Well Water Samples1 Type Parameter Collection Procedures

Chemical/Physical Parameters

Arsenic Barium

Cadmium Chromium

Cyanide Fluoride

Iron, Total Lead

Manganese, Total Mercury Nitrate Nitrite

Selenium Sodium Sulfate Zinc

Calcium Chloride

Magnesium Potassium

Alkalinity

Color Conductivity2

Carbon Dioxide (CO2) Dissolved Oxygen (DO) Hardness (Total and Ca) Hydrogen sulfide (H2S) pH2 Temperature2

Total Dissolved Solids (TDS) 2 Turbidity

Samples should be collected after the well has been pumped (or bailed) long enough to remove standing water, mud and other foreign material, including development and disinfectant chemicals, so as to insure that ground water has entered the well and the sample is representative of the water in the aquifer(s) .

Bacteriological Total and Fecal Coliform Total Plate Count

Testing for bacteriological quality is the final step in well completion. The sample is collected from the pump discharge after the well has been disinfected and the chlorine removed by pumping.

4.0 MATERIALS, TOOLS AND PERSONNEL

4.1 As requested under this contract, the contractor shall provide all the materials, tools and equipment for proper installation of the well and connection of the pump. The inbound and outbound shipping cost for the tools or equipment is the responsibility of the contractor.

4.2 G.2 calls for the contractor to have its own medical insurance and any other type of insurance required by local laws. The contractor shall also set up a Medical Evacuation Plan in case of a real emergency during the period of performance.

The contractor is required per Section G.5 to provide in advance the names and National Identification Number of all personnel who will access the site. The contractor is also required to provide all vehicle ID plates or equipment ID plates with all drivers’ names 3 days prior to access to the site.

The contractor should designate a point of contact or a supervisor with phones numbers to contact during the period of performance.

The contractor will not be allowed to bring any electronic devices or cellular phones exception for their supervisor, and this should be approved in advance.

5.0 WRITTEN REPORT

The contractor is required to provide the following written reports:

a) Field documentation report to include:

i. Casing material, diameter, and depth below grade

ii. Screen material, construction, diameter, and opening size

iii. Pumping test with static water level, maximum safe yield, and drawdown at maximum yield

iv. Well log indicating strata encountered

b) Operation and Maintenance information for each well pump, [valves, motors, and well screen] to include in emergency, operation, and maintenance manuals.

c) List of recommendations for repair and improvements with proposed costs to ensure the well is performing per the original design.

a) Copy of all inspection and test results (hydrostatic, water quality analysis, performance test data).

b) Debrief to Embassy point of contact.

c) List of immediate safety issues

6.0 ATTACHMENTS

6.1 Attachment #1: Site Map of well location

6.2 Attachment # 2: Pump House

2 D drawing.

END OF SOW