Lakhasly

The area to be excavated shall be free and clear of any materials stored related to other packages that might hinder a continuous and smooth working environment. All these materials shall be removed and transferred out of the border of excavation areas.

Dust that will be generated during excavation shall be controlled by regular spraying/sprinkling of water through the use of water trucks.

Adequate safeguards and barriers will be provided to prevent workers inside excavations from surface hazards, as well as to provide pedestrians and motorists with safeguards that prevent falling, walking, or driving into open excavations. This requirement pertains to any excavation within twenty (20) meters of a pedestrian walkway or road.

Solid barriers will be placed around all excavations over 1.2m deep at a distance at least 1.2m. Where night-time pedestrian or vehicle access is adjacent to excavation, then all solid barriers will be fitted with warning lights.

Prior to start, the excavation works, the Surveyor will verify the current excavation level by taking the As-built Survey and furnish the site team for their reference.

The works shall be closely monitored by Surveyor to ensure that the required formation-level will be reached and avoiding any over-excavation.

Excavation works shall be done as follows:

Excavation will be carried out using a combination of excavators with hydraulic rock breaking hammers.

Number of equipment within the combination will be deployed in the project site and shall work simultaneously. All excavation equipment will be fitted with sound suppression devices such as mufflers or as recommended by manufacturers.

Contractor to use multiple excavators and breaking hammer (if required) to adhere to the programme of works provided HSE rues are adhered to.

All personnel including operators/riggers shall wear adequate ear protection and respiratory face mask in addition to the required PPE’s on site. In order to keep dust emission to minimum levels, frequent water spraying will be done on the working area with the water trucks assigned for each location.

The contractor shall establish a maintenance scheme considering numerous equipment to be utilized for the project. Pre-inspection, repairs, greasing, and refueling activities shall be done on the area designated for the project including parking areas at the end of everyday work.

All extracted materials from the excavation site shall be properly hauled by loading onto Dump Trucks / Tipper Trailers using Wheel Loaders or Bucket Excavators and shall be disposed only to the approved disposal area directed by the Consultant.

Precautions shall be practiced while loading excavated materials since overloading might happen that will be dangerous during transportation. Loading shall be strictly monitored and ensure all dump trucks/tipper trailers will only carry as per maximum required loading capacity to prevent overloading that will result in an uncontrollable wheel and or tipping or slanting. The type of trucks to be used for hauling operation shall have a capacity of between 16m³ – 19m³ for smaller dump trucks and 22m³ – 32m³ for much bigger dump trucks. To control the weights being loaded on each truck, a weighbridge shall be in place.

All trucks/vehicles shall have a maximum speed limit of 15 km/hr. which will be imposed strictly and any violators shall be noted for fine/removal on the site premises.

The supervisor will closely monitor the loading of materials and will assign “Spotter” to guide and control the required maximum volume every dump truck should carry. A vantage point in the form of a scaffold tower will be erected for monitoring.

A “Checker” will record per trip all dump trucks loaded/leaving from the hauling area and a separate recording will be done while dumping on the temporary stockpile/storage area in order to monitor the volume of excavated materials. The “Checker” will be stationed at the exit point most probably at the level ground before entering the ramps. Each trip of the truck shall be recorded with truck details (i.e. Body Number, Driver’s Name, etc.) with the driver’s signature for each corresponding trip.

All equipment/vehicles to be used during the operation shall have an operational A/C unit, especially during the summer period.

All dump trucks to be used upon transporting excavated materials inside or outside site premises shall be covered with mats or safety nets to ensure that materials are intact and there will be no dust formation or scattering/falling objects.

Dump trucks shall not be over-filled not to exceed the top level of the hopper for easy fixing of mats or safety nets.

Option 1: Dump truck to be fitted with mechanically operated rolling cover mats or safety nets pulled by a rope in position (see sample attached).

Option 2: Mats or safety nets shall be spread evenly to cover the entire hopper by personnel using ladders to hook the nets to the edges of the hopper. Personnel on the ladder fixing the mats or safety nets shall be assisted by another worker on the ground holding the ladder secure.

In the event of transporting/disposing of unsuitable materials outside site premises, ensure that all wheels of dump trucks are thoroughly cleaned and Dump Box shall not be deteriorated to prevent falling of materials while entering the main road. Prior to moving out on the excavation area, all trucks will drive across a rumble strips above a catch pit to remove collected materials from wheels.

Any purpose of use of all excavated/extracted materials on site shall be underwritten permission from the client through the Consultant as per project specification requirements. Furthermore, all extracted materials shall be hauled and stored and/or disposed of only on the areas approved by the Client and/or Municipality as applicable, with information and under the supervision of the Consultant staff.

Excavated materials arising from the project area shall be hauled and stored at a dedicated contractor stockpile area.

Stockpile area shall be of adequate distance from the excavation areas and a bulldozer and/or a wheel loader will periodically grade the stockpile to allow stockpiling the material in layers and give the area neat and healthy look. Provision of safety nets around the perimeter of stockpiles to prevent unexpected wearing down/rolling of rock pieces or soil materials.

The final 0.5m of rock layer before reaching the formation level shall be excavated using light jackhammers to ensure the integrity of the founding stratum after the excavation is complete. In case after reaching the formation level, any loose or unsuitable surface found during the inspection of the consultant will be removed and will be backfilled with C30 concrete or suitable soil materials in accordance with the approved Method Statement.

The formation level shall be checked by Surveyor once the excavation is done in accordance with approved shop drawings where the final formation levels shall comply with the approved design requirements. Any over-excavation shall be backfilled with C30 concrete and work shall be done as per approved Method Statement for Backfilling Works using C30 Mass Concrete (for Over Excavated Areas and Unsuitable Soil / Surface).

The final excavation level shall be leveled together with the side slope shall be trimmed and shall be free from any loose/soft materials. The area will be clean and free from debris, deleterious materials, and any unsuitable soil/surface as defined in project specifications.

The final excavated surface at approved levels is restricted against vehicle accessibility. Damaged foundation materials due to passage of vehicles or other detrimental factors shall be repaired by the Contractor at no extra cost, and to the approval of the Engineer.

Maintenance of access ramps and access routes shall be done periodically for easy and convenient working conditions. Access ramps shall be properly sloped, graded and embankment shall be properly shored/supported. Both sides of access ramps shall be installed with a concrete barrier for fall protection.

Access roads shall be maintained by proper grading, backfilling and compaction of heavily degraded portions. Continuous water spraying shall be done to prevent dust formation which is hazardous to everyone’s health.