cleaning of under ground , overhead water tank on quarterly basis , cleaning of gully traps , manholes etc , cleaning of sewerline manually at delhi state cancer institute ( east ) , dilshad garden and janakpuri ( west ) , delhi . ( re-call ) , cleaning , cleaning of terrace/loft water storage tank ( inside surface area ) upto 5000 litre capacity at all heights with coconut brushes , duster etc . , removal of silt , rubbish from the tank and cleaning the tank with fresh water disinfecting with bleaching powder @ 0 . 5gm per litre capacity of tank , including marking the date of cleaning on the side of tank body with the help of stencil and paint and disposing of malba , all complete outside hospital campus as per direction of engineer-in-charge . ( the old date already written on tank should be removed with paint remover or black paint and if date is not written with the stencil or old date is not removed deduction will be made @ rs . 0 . 10 per litre if during cleaningany gi fittings or ball cock is damaged that is to be repairedby contractor at his own cost and nothing extra will be paid on this account , cleaning and desilting of gully trap chamber , including removal of rubbish mixed with earth etc . and disposal of same , all including disposal malba/slit complete outside hospital campus as per the direction of engineer-in-charge , cleaning of under ground sump , over head r . c . c . tank ( independent staging ) including disposal of slit and rubbish , including disposal malba/slit all complete outside hospital campus 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 . , cleaning of chocked sewer line manually by skilled labour , beldar etc . including cleaning and partial desilting of manholes and de chocking of sewer lines . de chocking and flushing of sewer line from one manhole to another for sewer line from 150mm dia upto 300mm dia for all depth including disposal malba/slit all complete outside hospital campus as per direction of engineer-in-charge . , collection of water samples for physical , chemical and bacteriological analysis of water testing ( essential parameters ) as per is:10500 , water collected from under ground tanks of dsci ( east ) as per direction of engineer-in-charge