MethodStatement for Project 209-5

VILLA-48 VILLAS AT MOHAMMED BIN ZYED CITY

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DELMA/MS/003

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Trenching & Excavation

METHOD STATEMENTS TRENCHING AND EXCAVATION MS/WW/003

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12/18/2014

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VILLA-48 VILLAS AT MOHAMMED BIN ZYED CITY

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DELMA/MS/003

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Trenching & Excavation

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SIGNATURE OF THE DESIGNATED PERSON 0

18-Dec-14

Issue for Approval

Rev

Date

Description/Detail of Amendment

Prepared By QAQCE

Reviewed By QAQCM

Approved By PM/P’sM

DOCUMENT REVISION

1.0 Purpose 1.1

To ensure that Trenching/excavation and related activities are executed safely and in accordance with the contract requirements and that all quality assurance / control activities are conducted in a systematic manner, works are inspected and conformance is verified and documented.

2.0 Scope of Work 2.1 2.2

This procedure is applicable to the following works associated with the project. This method statement outlines the procedures to be followed in the Trenching/Excavation for the construction of Pipe lines at locations shown on Contract Drawings and as directed by Client / Consultant.

3.0 Definitions 3.1 3.2 3.3 3.4 3.5

P’sM PM SE SU HSEO

Project’s Manager Project Manager Site Engineer Surveyor Health ,Safety & Environmental Officer

4.0 References 4.1 4.2 4.3

Specifications: Contract Documents. Drawings: Approved shop drawings. B.O.Q: Bill of Quantities.

5.0 Materials 5.1 5.2

Sheet Piles Box Frames (as per site condition if required)

6.0 Tools, Plant & Equipment 6.1 6.2 6.3

Excavator. JCB Crane

VILLA-48 VILLAS AT MOHAMMED BIN ZYED CITY

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Shovel & Trucks Surveying equipments to check level and alignments.

7.0 Safety 7.1

Prior to the commencement of any activities, the workforce will receive an inductiontalk on the Project site safety requirements. This induction talk will include both activity safety issues, as well as general safety requirements.

7.2

Where possible hazards may arise from Trenching/Excavation related activities, the necessary safety measures will be taken to prevent accident or injury at all times. This may include barriers, warning tape/ Net, signage, watchman, and proper lighting.

7.3

HSEO will enforce that Personal Protective Equipment be worn by site personnel at all times during construction activities.

7.4

Heat Stress Training will be provided.

7.5

Provisions of adequate cool drinking water, shade, and salt water tablets will be in place.

7.6

Plant & Equipment will be provided back-up alarms, lights, and all other applicable safety Devices.

8.0 Prior Activities 8.1

Identification and setting out of all existing services in proximity of the pipeline route.

8.2

Obtain approval of Service Reservation / Pipeline route.

8.3

Approval of shop drawings for water pipeline layout and pipe line profile.

8.4

Setting out of the pipeline route.

9.0 Procedure      



De-watering (if required) will start after verification of the clearance of utilities. Excavation status and level shall be controlled by surveyor strictly. Excavation will be kept free from water. The depth of excavation shall be as per approved shop drawings for the pipeline profile. The width of trench shall be as per specification. Excavation to be executed up to the approved invert level (as per the approved shop drawings for pipeline profile). In case the soil is not suitable to accommodate the pipeline, the excavation shall be 10 cm deeper than the invert level and a suitable / approved bedding layer will be laid as per the specification. Soft, spongy, unstable materials at formation levels shall be removed and replaced by selected grade materials as per contract specification in specific compacted layers.

VILLA-48 VILLAS AT MOHAMMED BIN ZYED CITY

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DELMA/MS/003

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Trenching & Excavation

Date

12/18/2014

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The bottom of all trenches (pipeline & structures) shall be prepared to correct formation level. In case of sandy soil and if actually required, the same can be stabilized before the excavation through the pouring of water. In case the depth of excavation is above 1.5 m, suitable safety measures/arrangements shall be adopted in order to allow the manpower to enter the trench for the required operations. The following solutions should be considered, proposed and described through specific procedures /method statements: shoring, profiling of the side walls of the trench through suitable slopes, storage of the excavated material at a suitable distance from the limit/edge of trench. Minimum depth of cover for the pipe shall be 900 mm from the ground level (finished) to the crown of pipe. Minimum width of the trench shall be the outside diameter of pipe plus 300 mm on each side. The depth if excavated trench, as per approved shop drawings, shall be documented in the specific quality control form. (Excavation and Backfill Record Form attached). Engineer will check the progress at intervals. Compaction test will be taken as per specification.

10.0 Responsibilities 10.1 Site Engineer: To co-ordinate with consultant, supervise the site works and ensure quality and safety procedures are implemented as required.

10.2 Foreman: To supervise the site works, Control of Manpower and ensures quality and safety procedures are implemented as required. To supervise survey team and ensure that shop drawings are properly followed. 10.4 Surveyor: To check the limits of excavation, to check the levels and alignments and to locate existing services ahead of pipe laying 10.5 Chainman: To assist surveyor 10.6 Operators: To operate the machineries on site and follow safety procedures as required.

10.3 Chief Surveyor:

11.0 Attachments 11.1 Inspection Request Form 11.2 Excavation and Backfill Record Form 11.3 Hazard Aspects/Impact and Risk Assessment for Trenching and Excavation.