Operation & Maintenance Of Ci/Di/Ac/Upvc/Gi Rising Main And Distribution System Of Water Supply Scheme Including Cleaning Of Over Head Tank And Regular Cleaning Of Sewer Line From Hospital Complex To Disposal Including Cleaning Of Other Allied Structures Of Hospital Complex Of N.S.S Covid Hospital And Adjacent Nurses/Doctors' Hostel At Nss Hospital Under Nadia Division, Phe Dte. For One Year