Massive expansion

THE TURBINE GENERATOR at Unit-1 of KKNPP. Steam generated by the reactor drives it to produce electricity, which is wheeled into the grid.-A. SHAIKMOHIDEEN

IN front of us, more than a kilometre away, are the aquamarine waters of the Gulf of Mannar. On the shore is an office of M.V. Ranga Prasad & Co, a contractor for Nuclear Power Corporation of India Limited (NPCIL). Some distance away to our left rise the domed reactor buildings of the first two units of the Kudankulam Nuclear Power Project (KKNPP). There are more mounds of soil and rock to our right. A little distance away is a small board that announces "RB-4" (Reactor Building-4).

"Where we stand is the stockyard of all the earth that we took out," said K.S. Rao, Project Director, KKNPP-3 and 4. "We excavated 1.5 lakh cubic metres of soil and rock a month to level the site. We did this for 10 months," he said. Rocks had to be blasted in a controlled way so that the shock waves travelling under ground would not affect the reactor and turbine buildings of the first two units, which are more than a kilometre away. Today, grading and levelling of the site is over for KKNPP-3, 4, 5 and 6. "We are now laying roads and intercepting drains. This location has a lot of natural drains. We have to make provisions for them," he said.

Technical requirements demand that one level at the site be 3.5 metres above mean sea level (MSL), while another be 9 m above MSL and yet another terrace 13 m above MSL. "Various buildings have to be built at different levels to meet the design criteria for the four additional units," Rao explained.

All is set for a massive expansion of the KKNPP with four more Russian VVER units to be built adjoining the first two units whose construction is almost over. Things have already pressed ahead for the start of the construction of units 3, 4, 5 and 6. An inter-governmental agreement was signed by India and Russia in December 2008 for building these four units.

The groundwork for the construction of the third and fourth reactors will begin early in 2010. There will be a two-year gap in the completion of the construction of the two pairs of units. Between the third and fourth units, the gap will be six months.

The geotechnical investigation of the site for Kudankulam- 3, 4, 5 and 6 involved extensive testing of rock and soil. Rao said, "We drilled about 330 boreholes, even to a depth of 100 metres, to understand the rock, soil and water quality, whether there is any water seepage [from the sea], and so on. The services of the Centre for Earth Science Studies, Thiruvananthapuram, were used to study the ocean behaviour."

With the geotechnical investigation complete, "we worked out a strategy for plant layout, infrastructure layout and the additional township. We will have to plan for power evacuation [to the grid] also because there will be a generation of 4,000 MWe [from the additional four units]," Rao said.

He praised the vision of V.K. Chaturvedi, former Chairperson and Managing Director of NPCIL, S.K. Jain, the current incumbent, and the late S.K. Agrawal, who was Director (Projects) and Project Director, KKNPP, for acquiring 1,058 acres (1 acre = 0.4 hectares) in one stretch. This has facilitated six reactors coming up in a straight line on the shore.

As in the case of Kudankulam-1 and 2, Atomstroyexport, the Russian nuclear monopoly, will provide the drawings and equipment for the four additional reactors, and NPCIL will build them. Rao is confident that the reactors can be built fast. "We have also understood the sequence of construction of Light Water Reactors by building the first two units. So we can economise on the time cycle," he said.

According to V. Rajesh, Additional Chief Engineer, Kudankulam-3 and 4, the mini-port, which now exists opposite the first two units, will be shifted closer to the four additional units because heavy equipment from Russia will come by sea.

NPCIL has set up eight windmills near the project site, each generating 1.25 MWe of clean energy. Ravi Kamath, Project Engineer (electrical), NPCIL, pointed out that Kudankulam and the locality around it was "a wind-intense area" and wind blew all through the year. NPCIL sold the power generated from the windmills to the Tamil Nadu Electricity Board. The utility is now planning to use this power for the township.

"There is a big plan for expansion. [Initially], we will put up eight more windmills. This area [Mupanthal, Aralvoilmozhi, Chettikulam, and so on] has about 4,000 windmills. It shows that conventional and non-conventional sources of energy can coexist in the same place," said Kamath.