Attachment 2 Scope of Work.pdf

LTD

A/e services to replace the sewer system and create ADA pedestrian ramp at

Arnona

Contract No.1910S40-22-c-0009

Scope of Works

Final Submission

April, 10th, 2023 Warning: This document is the property of the U.S. Government.

Further reproduction and for distribution is prohibited without the

Express written permission of: American Embassy .18 AGRON Road –

Jerusalem. Information on this document is not to be altered

Except with the written approval of this individual whose seal appears hereon.

DixonLJ Permitting OBO_STAMO

DixonLJ Typewritten Text 5/9/2023

DixonLJ Typewritten Text 23-0113

November, 2022

USA Embassy Jerusalem

Scope of works and specifications

Existing situation:

I. The sewage system:

The sewage system running through the US Embassy premises in Arnona neighborhood in

Jerusalem, has been facing some problems, causing system closure and other similar discomforts.

Tests were done to point out the reasons for this malfunction.

A camera Robot was administered into the whole network to point out the problems

A major problem was the negative slope of the pipes between manholes. This issue caused the sewage to run backwards in the opposite direction, and as a result, a stand still. Accumulation of solid waste resulted in the closure of the pipes or the connection at that specific place and causing blockages.

Unfortunately, this negative slope was seen in large portion of the network

There were other problems like broken pipes, bad connections, torn flanges and others

Objectives:

Our goal in this project is to get the system working with minimum and regular maintenance.

This will be done by fixing the slopes into the right direction and angle, as well as fixing all the torn parts of the system

Works:

Before the start of the works, the contractor shall submit a detailed time schedule to be approved by site engineer, the contractor shall also submit shop drawings for all the works, including all phases of the works with all finishes.

Submittals:

The contractor shall submit all items he will supply for the entire project by the supervisor engineer.

I. Civil works part A:

The needed bottom and top levels of most of the existing manholes do not match the required levels, there is a need to fully replace them by new ones.

Once these manholes are installed, new pipes with the specified diameter will be installed with the right connections as per specifications

Excavations parallel to the existing sewage system will be carried out, taking into consideration the bottom level of the new manholes, and all the bedding needed as per profile plan #M02

The contractor shall make a wide enough excavation that will let him maneuver his works easily, for applying connections, and installations.

The same applies for the diameter of excavation for the manholes

It is important to note that there are several kinds of finish surface at the site e.g. natural soil, tiles, key stone, or aggregates. When making the excavations the contractor shall care to restore this finish as per origin

To do that, the contractor shall do the following steps in each case, and shall provide shop drawings for the excavations and restorations for the following:

A) Soil: dig with care for any infrastructure. In case of any infrastructure found, consult with supervising engineer and Embassy personnel to find solutions. After finishing the works and cover of the pipes and surroundings, the soil finish will be restored to match the nearby soil

B) Stone Tiles: beneath the tiles to be removed will be selected carefully. With a mechanical saw, the pointing will be removed, and deeper cutting will be administered, to be able to remove the specific tiles without damaging the adjacent tiles. In case there is a concrete layer below the tiles (most likely) the specified are for excavation will be cut with mechanical saw, causing no damage to the surrounding structures. The rest of the excavation will be carried out carefully until the designated level is reached. In case of any infrastructure found, consult with supervising engineer and Embassy personnel to find solutions.

C) Aggregates: The area for excavation will be marked. The layer of aggregates will be removed, The rest of the excavation will be carried. Aggregates layer to be relayed after the sewage network has been installed and tested.

out carefully until the designated level is reached. In case of any infrastructure found, consult with supervising engineer and Embassy personnel to find solutions.

D) Key stone: The area for excavation will be marked. The designated tiles will be marked in case of several colors (pictures can be of help) and removed and stored in a suitable place to reinstall afterwards. The rest of the excavation will be carried out carefully until the designated level is reached. In case of any infrastructure found, consult with supervising engineer and Embassy personnel to find solutions.

Once the excavations are ready beddings will be prepared as per detailed plans & details in M04 and

M05

Kindly note that these works can be done in segments with a thorough preparation of levels.

And the right connections between segments.

All trenching / excavation for new utility should be done in compliance with OSHA

2- Mechanical works:

The construction works required for changing and replacing the existing 160mm sewer PVC lines at as shown in the attached new design sewage plans to better meet the depths and slopes, which describe the sequence of connection plan to the utility infrastructure and to keep up the sewer system running at all times; according to the new design drawings could be summarized as follows:

1) Topographical survey for top and bottom levels of existing manholes (not to be replaced) and new manholes (located adjacent to near existing and replaced manholes).

2) Digging and excavation along and around the path of the new sewage pipes according the routes shown in the design drawings down to the appropriate invert levels of manholes and pipes (as per profile drawing for pipes and depths levels shown on manholes schedule plan).

This step shall be executed carefully to ensure that there are no existing installations of water pipes, fire pipes, electrical conduits and others (if there) at the zone or region of excavation.

3) Placing the new manholes (MH-2, MH-5, MH-6, MH-6.1, MH-7, MH-8, and MH-8.1) on their locations as shown on drawings after levelling under the manholes.

4) Laying and installing of the new sewage pipes according to the route shown on the drawing

(green color path) and placing concrete bases at certain interval distances along the pipes for fixation and slope aligning of the pipes (1.5% gradient)

5) Connecting the sewage pipes with the new manholes after making holes openings on the manholes walls at the levels determined and calculated according to top and invert levels of pipes entering and leaving the manholes respectively.

6) Closing gaps around pipes penetrating the manholes using special water-proof insulated material as per engineer approval.

7) Making water leakage test for manholes and pipes according to specifications and criteria agreed with engineer. This step could be accomplished in portions.

8) Laying a layer of sand under the pipes, and on their sides and above, with thickness shown on specifications and tamping by plain concrete with a thickness fit with the levels, shown in the drawings.

9) Making fine coarse plastering of new manholes walls, and benching the bottom of the manholes as per drawings and specifications.

10) Repairing and treating of cracks (where found) in the walls of the existing manholes using special certified and approved compound material.

11) Installing of new concrete trench with its floor drain as per location shown on drawings with its steel frame. The works include drainage pipes connection to existing drain pipe.

12) Arranging and coordinating with the Embassy administration to stop the neighboring buildings from using the water and the drainage network leading to the external (existing) network for two days (may be at the end of the week) for the purpose of:

A) Connecting their pipes to the new manholes.

B) Connecting the new sewage adjacent pipes with the near existing manholes.

C) Benching works of the existing manholes along with the angle of new entry and exit sewage pipes connected to manholes.

D) Plastering of manholes walls (if needed) and closing the existing openings of old

(cancelled) pipes connected to current manholes with cement compound of approved material.

E) Making leakage test of the existing manholes with the same procedure as mentioned above for the new manholes.

13) Installing of manholes covers.

14) Final testing, commissioning and works preliminary handing over.

After finishing all the mechanical works, and prior to filling above the pipes and around the manholes, it is required to do the necessary testing to make sure the system works well.

These tests including the robot camera will be on the expense of the contractor, and all reports will be handed to the supervising engineer.

In case any part wrong after tests. This part will be fixed and the whole tests will be redone to make sure all is right (on the expense of the contractor).

3- Civil works part B

After filling the finish surface will be restored as originally was.

It is worth noting the following:

Stone Tiles finish: similar tiles in kind, size, texture will be used for finishing surface

In case there is a slab on grade below the tiles originally, the new slab on grade under the new tiles will be casted with steel rods joining the old and new (FI 10@20 cm)

Aggregates: the necessary base coarse compaction works will be done and a layer of aggregates similar to existing & original will be laid in place of old aggregates

Keystone: the necessary base coarse compaction works will be done and a layer of sand will be laid to receive the stored tiles taken away previously.

Soil: the surface of the soil will be restored as originally was. With the necessary plantation if existed in the specific area.

II. The ADA pedestrian Ramp:

In part of the walkway within the premises, there is one section where the only way to reach is through an open stairway (7 steps)

Objectives:

To remake the pathway into a suitable ADA compliant ramp with respect to safety and other measurements.

Works:

Before the start of the works shall submit a detailed time schedule to be approved by site engineer.

The contractor shall also submit shop drawings for all the works, including all phases of the works with all finishes, Submittals:

The contractor shall submit all items he will supply for the entire project by the supervisor engineer.

Civil works:

The contractor shall carefully remove the stairs as marked in plan A102

These stairs can be kept in a safe place to be partially used when reinstalling them at the right phase of works.

It is noted that any break of the stones, or mismatching of the dimensions will be at the contractor’s expenses to bring substitutes.

Any substitute for the stones has to match in origin, quality, and texture and pattern (interlocking or running bond pattern to be maintained)

The stone tiles in the pathway will be removed to set space for the foundation of the structure (see plan A102 and A202)

The contractor shall carry the excavation works as per plan A101, A102, taking into consideration, cutting the pointing prior to removing the stone tiles, cutting any concrete (slab on grade) by mechanical saw. In case of any infrastructure found, consult with supervising engineer and Embassy personnel to find solutions

In this space there is a rain water trench connected to the sewage system. This trench will be removed, pipes extended to the new position as per plan, and a new similar one will be installed.

Pouring the blinding concrete after laying the polyurethane sheets, painting the foundation and retaining wall with special membrane (bitumen waterproofing membrane) minimum after 2 days from casting.

Installing all steelwork and shuttering of the foundations as per plan. Concrete pouring of B300, with suitable vibration. The contractor shall administer concrete testing from an approved lab.

After the casting in two days, the wood shuttering will be removed and all the foundations will be painted with membrane as noted in BOQ (item #6)

New shuttering will be done for the retaining wall with all steel works as per plans and BOQ

Base coarse will be filled in with the right compaction see BOQ item # 2.6

A polythene sheet will cover the finish level of the base coarse, ready for steel mesh to be placed and concrete casted on it

The new level will be tiled with similar stone tiles, similar in origin, color, texture and size.

Mortar for tiling will be used cement: sand / 1:3 ratio

Pointing with white cement and sand 1:3 will be applied to new stone tiles

The wall will be cladded from one side with the galvanized steel mesh anchored to the wall with cement / sand 1:3 mortar 5 cm thick, all as per drawing detail # A204

Note that the plate for the rails will be fixed and anchored before installing coping tiles

Stone coping will be installed 5cm thick with fillet form both sides, all as per detail # A202 section 2-2. Same mortar will be used

Above coping a galvanized steel railing as per drawing will be installed with additional handle bars at 950 mm high and 750 mm high.

Another wall mounted galvanized steel hand rail with loop like shape will be installed at the opposite existing stone wall. See sheet A203 and 3D images in A205

Two more wall mounted handrails at 900mm height will be installed at the stair leading to the upper level, one side to be mounted on the existing building and the other will be mounted partly on the new retaining wall & the new Ramp’s handrail, including all the accessories, hangers and welding.

All handrails will be coated with hammerton Dulux rough granulated paint (see catalogue)

This stair will be retiled with either the existing stair tiles or with new ones similar in origin, texture and size. Stair tread and risers will be of the same texture, the nosing will be 2cm extruding over the riser with a filleted/chamfered corner as per detail ST1 in Sheet A204

Same mortar and pointing as stone tiles will be used.