National Environmental Engineering Research Institute Tender

Second Cleaning in a year ( For next six months of contract after completion of first cleaning) Cleaning of Under ground & Overhead water storage reservoirs and tanks of any height as per the hygienic & scientific methods of tank cleaning as per specification , procedure(attached in Annexure 'A' * and instruction of Engineer in charge . ( polythelene and RCC tank) arge . ( polythelene and RCC tank)

Storage Capacity more than 25000 - 1000000 Ltrs.

Storage Capacity from 500 to 5000 Ltrs.

Annexure 'A' Procedure to be adopted for Tank cleaning Stage I In the first stage of Tank cleaning involves the thoroughly cleaning of the manhole and surroundings which is usually full of dirt, mud and algae. Stage II The process further continues with cleaning of the walls and ceiling of the tanks with special high pressure jet which dislodges the layer of dirt and algae which sticks on the walls and ceiling of the tank. The cleaning of this tank fully removes the layer of calcinations and dirt. This is the only method of cleaning where it is physically possible to clean the ceiling thoroughly. The ceiling incidentally has a very high concentration of germs and bacteria due to the availability of oxygen and dampness arising out of condensation of the water vapour. Stage III After cleaning of all the walls and the ceiling totally, the dirty water and sludge is removed using a special sludge pump. This pump disposes off the dirty sludge to any convenient and safe place outside the drinking water tank.

Stage IV After removal of major part of sludge the floor of the tank is to be thoroughly cleaned by the high pressure water jet removing all the remaining dirt and algae. The remaining sludge is again removed by our special high pressure vacuum pump. The same process is adapted for the overhead terrace tanks as well. After the sludge is removed the remaining dirt is vacuumed out using a Vacuum Cleaner making the floor of the tank totally dirt free. The sludge is then taken out of the tank and disposed off to a safe place. Stage V The next important process is the treatment at the inside walls and the ceiling by disinficent agents which ensures that the entire surface of the walls and ceiling is made totally sterilsed from any disease causing the bacteria’s. The anti-bacterial agents are thoroughly sprayed in all the nooks and corners of the tank which ensures total sterilization of the tank from the inside. Stage VI In the final and the most important stage of the cleaning the inside of the tanks with UV Radiator which kills any further suspended or floating bacteria that might have remained in the tank.After this a drinking water tank which gets totally clean, bacteria-free and safe for storing drinking water.

Note:- Contractor may visit the site before quoting the rates.Tools , plants, Dewatering pumps ,plumbing related damage and issue including labour and material like sterilised boot, gloves etc. shall be arranged /provided by the contractor. Contractor has to quote his rate in word as well as in figure(for one time cleaning) and it should be inclusive of all safety precautions required for the work. Cleaning will be done twice in a year. Deductions for GST, Income tax, Building worker Cess and electricity charges as per actual consumption will be made from the bill.Time period for each cleaning will be two months. Second cleaning will be done six months after the first cleaning.