The Tarapur Atomic Power Project-4 has entered the phase of commissioning. This is within four years from the first pour of concreting (zero date). A monthly average of 25,000 inch-diameter welding and about 35,000 inch-meter erection of piping has helped complete all the major systems of the unit in time.

Fresh water system, auxiliary cooling water system, fire hydrant system, end-shield cooling system, part calandria vault cooling system have been commissioned and operating from the control room. Production of de-mineralized water is in full swing to meet the commissioning requirement. Test run of all auxiliary service water pumps and service water pumps has also been completed. Different categories of compressors and chillers are under commissioning. Testing of heavy water recovery system is also nearing completion. The turbo generator has been boxed up. Installation of incoming and outgoing transmission power lines is in progress. The system needed for hydro-test has been commissioned ahead of schedule. So far 93 per cent of TAPP-4 is over.

The progress of TAPP-3 has also picked up a momentum. Three steam generators are already installed and electrical, piping and instrumentation system is progressing as per schedule.

The dream of constructing a nuclear power plant in less than six years will be fulfilled for the first time by TAPP-4, which has a 540 MW pressurized Heavy Water Reactor (PHWR).