13 of 49 Construction of Giresun Wastewater Treatment Plant  Tender Dossier Volume 3 Employer’s Requirements  Section 05: Earth Works, Pipe Works and Ground Improvement  Operations on earthwork shall be suspended at any time when satisfactory results cannot be obtained  because of rain, or other unsatisfactory field conditions. The Contractor shall drag, blade, or slope the  embankment to provide proper surface drainage.  The material in the layers shall be of the proper moisture content before compaction. Wetting or dry- ing of the material and manipulation when necessary to secure uniform moisture content throughout  the layer may be required.  The Contractor shall take all necessary precautions to protect exposed faces against deterioration.  The Contractor shall compact the fill using approved compacting methods and equipment. Backfilling  shall not impose uneven or excessive load on a structure.  All material used for filling shall be deposited and compacted as soon as practicable after excavation  in layers of thickness appropriate to the compaction plant used. Filling of areas and embankments shall  be built up evenly over the full width and shall be maintained at all times with a sufficient camber and  a surface sufficiently even to enable surface water to drain readily from them.  5.2.9.3 Trial Area of Filling  Where required by the Engineer and before commencing filling, the Contractor shall at his own ex- pense compact a trial area of filling of the type proposed using the equipment proposed for the works  in accordance with specified standards of compaction. The area shall be of a size and depth to the ap- proval of the Engineer sufficient for the trial to adequately represent the work involved in the general  filling operations.  Variations of method or equipment will only be permitted when the Contractor demonstrates by field  trials that the compaction obtained by the alternative method achieves compaction equivalent to that  obtained by the approved method.  During the progress of the works the Contractor shall inform the Engineer of any factors outside his  control which may adversely affect the compaction achieve so that the Engineer can give considera- tion to a variation of the equipment or method.  5.2.9.4 Filling Adjacent to Structures  Filling against the perimeter of structures shall not be carried out until the Engineer agrees that the  construction is sufficiently advanced implying no risk of interferences or damage from either the com- paction equipment or the backfilling material.  Filling material for excavations and for making up levels within the perimeter of structures shall be  suitable material and shall contain no particular size in excess of 50 mm. The compaction of fill mate- rial within the perimeter of structures shall be carried out with equipment suited to the area being  compacted.  5.2.9.5 Tolerances for Filling  5.2.9.6 Control and Testing of the Fill The fill shall be placed and compacted to a tolerance of –10 mm/+ 15 mm for a final surface. Where  further works will be carried out above the fill the tolerance shall be –25 mm/+0 mm.  Within the above tolerances the surface shall have a smooth regular face all to the approval of the En- gineer.  Control testing shall be carried out by members of the Contractor's staff competent to perform the re- quired tests. Additional testing may be carried out at the discretion of the Engineer.  Soil compaction tests shall be carried out according to the relevant standards.  5_Vol3_d4.3_Section 5 Earth and pipe works_en_GIR_rev6.docx 