Heavy Water Plant Thal is the first of second-generation plants in India and is made completely with indigenous efforts. The vast technical resources available with Heavy Water Board with the experience gained by commissioning and sustained operation of the earlier plants were utilised for setting up of the plant. It is located at Thal-Vaishet village in Raigad district of Maharashtra and is about 100 kms south of Mumbai on National Highway No.17 It is about 20 kms away from Pen railway station of Panvel - Roha section. The site is also accessible from Gateway of India, Mumbai by Catamaran services. HWP Thal was commissioned in 1987. Setting up of the plant was a major task as a number of components were to be developed for the first time indigenously. Some of them were special tower internals, canned motor pumps, glass seals, mass spectrometers, multilayer vessels etc. and this involved considerable pre-project effort by Heavy Water Board.

The plant adopts the latest technology using micro-processor based distributed digital control system for instrumentation and process control instead of the conventional pneumatic analogue system. The system provides supervisory and monitoring functions for feed control stations. It displays and records data acquired from the plant system and has facilities for data logging and printing alarm messages.

This plant comprises of two streams with some common units like synthesis unit, sub-station, inert gas unit, instrument air unit, catalyst preparation unit, cooling towers etc.

Completion of the project has been successfully achieved without any time overrun.