tender for cleaning/maintenance of underground sump and water storage tank; cleaning of underground sump, over head r.c.c. tank (independent staging) including disposal of silt and rubbish, all as per direction of engineer-in charge. the cleaning shall consist following operations:(i) tank shall be emptied of water by pumping & bottom shall be cleaned of slit and other deposits. (ii) entire surface area of the sump shall then scrubbed thoroughly with wire brush etc. and pressure washed with water.(iii) chlorination of rcc internal surface by liquid chlorine. (iv) the treated surface shall be dried using air jetting and all loose particles shall be removal from the surface.(v) finally the surface shall be treated with ultraviolet radiation etc. as per direction of engineer in-charge.note :- 1). the contractor/firm should ensure all safety precautions including all safety equipment to be taken care during the execution of the job and work to be executed only by trained manpower for the job. 2). cost of formwork/staging is included in the item, additional payment will not be paid for these.