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The Hit ListIn September 1970, Government of India constituted a national committee under the Chairmanship of Shri V.R. Vengurlekar to study in depth and recommend a panel of suitable sites for setting up nuclear power stations. The modus operandi adopted by the committee was to have site investigations carried out by agencies of the different states concerned On the basis of all the accumulated data the committee made comparative evaluations of various sites.
The recommendations of the committee have never been made available to the public,
despite repeated requests.. However, the International Atomic Energy Agency (IAEA) and the OECD Nuclear Energy Agency jointly organised a symposium on ‘Siting of Nuclear Facilities’ in Vienna from 9-13 December 1974. In it a member of the National Site Selection Committee Shri L. Venkatesh and T.P. Sarma of the Health Physics Division of BARC presented a paper entitled
‘Siting of Nuclear Power Stations in India.’ This paper contains the map published on page it as well as a set of guidelines which were used by the committee to determine the relative merits of different sites. The symposium proceedings were published in a book form by the IAEA in April 1975 I strongly recommend this paper as also another by S. Krishnamurthy and S.D. Soman on
siting considerations for fuel reprocessing plants (details in the next issue of Anumukti), to all
antinuclear activists in the country. Unfortunately access to this paper is not easy. Therefore in the following I shall highlight some of the points discussed in the paper.

Site Selection Criteria

Site Selection depends to some extent on the proposed type of reactor. The Indian programme is based primarily on the natural uranium fueled, heavy water moderated CANDU type of reactors. All sites were evaluated on the basis of their suitability for setting up CANDU reactors of 1000 MW (c) capacity in stages. (Thus, existing reactor sites, e. g. Tarapur, Rawatbhata, Kalpakkam are likely to have additional units constructed on them.)

Distance from coal deposits

Even after recourse to creative bookkeeping it makes no economic sense to locate, nuclear power plants in regions with large coal fields. The breakeven distance from coal fields beyond
which nuclear power is expected to be cheaper depends on further of factors like pithead prices and the transport costs of coal, the difference In capital costs in the construction of nuclear and coal powered units the unit size adopted for nuclear units, etc. Estimates of this breakeven distance range from 500 Km. to 800 Km from pithead.

Water requirements

Nuclear power plants are thirsty monsters. They require enormous quantities of water for both process cooling and condensor cooling. The amounts required for a 1000 MW (e) station are 300 cusecs of freshwater for process cooling and 2500 cusecs for condensor cooling. Thus nuclear power stations can only exist near large (1200-1500 acres) reservoirs or canals or on the sea coast with some additional freshwater availability. Even with these huge amounts the temperature of the outgoing condensor water gets raised by 8 degrees centigrade. This outfall water when let into a reservoir forms warm water zones which deplete the dissolved oxygen in the water and consequently provs fatal to fishes.

Condensor water is also used for disposal of liquid radioactive wastes during normal operation at coastal stations. In other words, the sea is used as a dump not only for the heat but also for the radioactivity. At inland sites where water is needed for irrigation and other community uses, this philosophy of dilution and dispersal comes a cropper. Inland sites thus need large cooling towers and storage ponds for chemical treatment and subsequent controlled release to the environment.

Electrical system

Nuclear plants are extremely capital intensive with comparatively low fuel costs and hence it is best to utilize them to the maximum extent, possible. ( In technical jargon—for base load with high load factor.) It is necessary that a good part of the power produced should be absorbed quickly after start-up to avoid problems of poisoning the reactor. This can be achieved satisfactorily only if there are large industrial loads in the grid in the vicinity of the plant which can come on line swiftly. For the satisfactory operation of the plant an assured supply of adequate start-up power of appropriate voltage from the grid is essential. The capacity of the nuclear plant should not be larger than 15% of the total capacity of all the generating units in the grid. Weaknesses in the grid can cause frequent tripping. The choice of the site of India’s first CANDU reactor at Rawatbhata in Rajasthan was subsequently strongly criticised by a review committee
appointed by the DAE itself (Prasad committee). The poor performance of the reactor was blamed on weaknesses in the grid.

Foundation conditions

The geologic stability, the seismic susceptibility and the tectonic features of the area are extremely important from the viewpoint of nuclear plant safety. The nature and the magnitude of any possible future earthquake needs to be accurately estimated from geophysical field experiments. This information helps in determining appropriate design parameters for the station structures, equipment and safety systems. Unfortunately, the science of earthquake prediction is still in its infancy the world over. Even in an extensively studied region like California, last month’s (1. 10. ’87.) Los Angeles earthquake was on a previously unknown fault. In India, as it is, the available local seismic history is rather short. As recently as December 1967, the peninsular shield of India was considered one of the stablest regions of earth free from all seismic activity. The Koyna earthquake put paid to all such comforting theories. Today, some
experts believe that human intervention in the environment, e. g. in the form of large dams,
can by itself be the cause of alterations in the geologic stability. Therefore, the zones should
be taken only as indicators of previous seismic history and not be considered too seriously as
determinants of future earthquake activity. In the aftermath of the Koyna earthquake, changes were instituted in the design of CANDU reactors as it was found that the design adopted
for Rawatbhata and Kalpakkam was inadequate to withstand moderate intensity tremours.
God help us if as a result of the Narmada project there are changes in the stability of
Madhyapradhesh — Rajasthan region.

Environmental conditions

In the normal course of operations, nuclear plants pollute the environment through controlled releases of radioactive nuclides in the form of gases. The acceptability of such releases at a given site depends upon the disposal capacity of the environment, the concentration and transport processes of radioactive products in the neighbourhood of the site, utilization of the environment and radiation safety standards. Under accident conditions, plant behaviour is not under control and large releases of radioactivity to the atmosphere may take place. It is because of this fear of disasterous accidents that plants are situated in areas of low population density.
Population distribution near the site, meteorological conditions, ground water flows, local environmental utilization arc all needed for site evaluation. At present, no residential population is permitted within 1.6 km of the plant and up to 4.8 k.m is only thinly populated. Administrative measures are used to restrict the growth of communities around the plant. Care needs to be taken to see that the predominant wind directions arc not towards any major population center. In
fact because of the frequent storms, hurricanes, heavy littoral drift, etc. most of the cast coast
of India has not been found suitable for reactor siting.

Access

Nuclear plant sites need to have good all weather roads connecting them to equipment manufacturing places as also ports of entry. The largest single piece involved for a 235
MW (e) unit is about 7.5 metres long and has a 7m diameter and weighs about 75 tons.
For a 500 MW unit a single piece may weigh anything up to 280 tons. Movement of such
heavy equipment to the site by tractor-trailer combination over long distances present many
problems. Great length of roads concerned need to be surveyed and improvements made
in bridges and culverts as well as changes made in road alignments and curves. All this takes
a great deal of time.

Conclusions

The moral of the story for the antinuclear activist :

Ideal nuclear sites arc hard to find. There are many exacting preconditions, some of
them mutually contradictory (low population density and close proximity to large industrial
centers) which need to be fulfilled by an adequate site. In its eagerness to promote nuclear power, the nuclear establishment has made choices like  Rawatbhata  which later experience has taught it to be true.

Any serious attempt to achieve the projected target of 10000 MW by the year 2000 AD would mean the prompt (next 2-3 years) acquisition of many of the sites shown in the map.

A strong antinuclear movement specially concentrated around the sites in the form of
well organised local groups can still prevent large scale nuclearisation  of India. It is not
yet too late.

Besides the points discussed above,  Indian reactor sites pose a special hazard.  The whole
programme is based on the reprocessing of spent   fuel   to   extract   plutonium.   Transport  of highly radioactive spent fuel between reactors and reprocessing plants is hazardous. Considering the road and traffic conditions at present in the country DAE proposes to build small
reprocessing plants right next to the reactors. Unfortunately this remedy is worse than the
disease it seeks to cure. Reprocessing plants arc a bigger menace to the surrounding environ-
ment than even reactors. The consensus of opinion the world over has been either to
dispense with reprocessing all together or to build large central reprocessing facilities and
take the transport risks. In the next issue of Anumukti I shall discuss siting criteria for
reprocessing plants.

Surendra Gadekar.

 

In September 1970, Government of India
constituted a national committee under the
Chairmanship of Shri V.R. Vengurlekar to
study in depth and recommend a panel of
suitable sites for setting up nuclear power
stations. The modus operandi adopted by
the committee was to have site investigations
carried out by agencies of the different states
concerned On the basis of all the accumulated
d a t a the committee made comparative evalua-
tions of various sites.

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