1 of 18  Construction of Giresun Wastewater Treatment Plant  Tender Dossier Volume 3 Employer’s Requirements  Section 06: Concrete and Steel Works  The Contractor shall analyze the groundwater in the project area in accordance to TS 3440. If the  groundwater is found to have aggressive effect on concrete, then the concrete used in structures in  contact with groundwater shall be made with sulphate-resisting Portland cement. Alternatively ground  granulated blast furnace slag (GGBFS) may be used together with Portland cement, complying with  EN197, in lieu of the Sulphate Resistant Portland Cement. In this case, the Contractor shall provide  the Engineer with the method on how to use the GGBFS cement.  Tests of Cement  The Contractor shall submit to the Engineer, free of charge, test certificates relating to each consign- ment of cement. Each certificate shall show that a sample of the consignment has been tested by the  manufacturer or by an approved laboratory and that it complies in all respects with the Herewith Em- ployer’s Requirements.  When required by the Engineer, the Contractor shall supply samples of cement taken on delivery to  site, or during storage on the site, for testing at a nominated laboratory free of charge.  No cement from any consignment shall be used without the approval of the Engineer and the Contrac- tor shall maintain a record of the locations of the concrete made from each consignment which record  shall be available for inspection by the Engineer.  If, for any reason, the Contractor shall decide to vary the source of supply, country or manufacture in  respect of any type of cement already approved by the Engineer at any time during the Contract, then  the Contractor shall give adequate notice of every such variation to the Engineer. The Contractor shall  carry out all the tests called for by the Engineer’s written approval of such variation before ordering  any material from the new source or supplier.  If cement has been stored on the site for more than 40 days or in the opinion of the Engineer is of  doubtful quality, new tests may be required, at the Contractor’s expense, to check whether or not the  cement still conforms to the requirements.  All cement shall be delivered to the site in properly and permanently marked, sound and sealed bags or  other approved containers, unless written approval from the Engineer is obtained for the delivery and  storage of cement in bulk.  Delivery and Storage of Cement  Rejection of Cement  Notwithstanding the receipt of the test certificate and the approval of the Engineer, the Engineer may  reject any cement as a result of further tests. The Engineer may also reject cement which has deterio- rated as a result of inadequate protection or other causes or in any other case where the cement is not  to his satisfaction. The Contractor shall remove all rejected cement from the site without delay at his  own expense.  Water for use in concrete, mortar mixing and curing shall be obtained from an approved source and  shall be of a quality that will not affect the setting time, strength, durability of the concrete or mortar,  or the appearance of hardened concrete or mortar by discoloration or efflorescence, or the reinforce- ment at any age of the concrete or mortar.  Quality of Water  Water shall be clean, potable, blended or unblended, with a pH between 5.0 and 9.0 and shall be tested  in accordance with TS EN 1008. The following limits shall not be exceeded:  6_Vol3_d4.3_Section 6 Concrete and steel works_en_GIR_rev6.docx 