Questions, and some answers

Print edition : September 25, 1999

QUESTIONS of safety relating to nuclear installations in the country have come up time and again, and those who raise them put the blame on lack of transparency on the part of the nuclear energy establishment. They say that the Department of Atomic Energ y (DAE) has not made public data about the levels of radioactivity released by nuclear stations and facilities, or about the cumulative exposure of each employee at the various nuclear power stations, the uranium mines in Bihar or the Nuclear Fuel Comple x in Hyderabad. These sections state that if the natural radiation levels recorded at a site by the Environmental Survey Laboratory (ESL) before work begins on a nuclear power project are made public, it will help measure any increase in radiation levels after the plant is commissioned.

Sceptics say that in cases where heavy water leak from a Pressurised Heavy Water Reactor (PHWR) occurred, no information was given out on whether it was the coolant heavy water or the moderator heavy water that leaked. (The radioactivity release from mod erator heavy water would be much higher than that from coolant heavy water.)

Issues relating to the decommissioning of ageing nuclear reactors are a cause for concern among environmentalists. In normal circumstances, a reactor is decommissioned 30 to 35 years after it attains criticality. On this criterion, two units of the Tarap ur Atomic Power Station (TAPS) are candidates for decommissioning as they started generating electricity in 1969. Further, the high cost of decommissioning is not factored into calculations of the total cost.

There are also fears about waste management. Nuclear waste may be vitrified, encased in metal cans and stored in underground repositories, but there is a risk that in the event of an earthquake, they may seep into the soil and water.

Whenever a nuclear power project is planned, it arouses fears among the local communities. This is especially so when the site is in a seismic zone (as is the case with the Narora Atomic Power Station) or in a densely forested area (the Kaiga Atomic Pow er Project) or on a coastal site (Kudangulam Atomic Power Project). In the case of Kudangulam, local fishermen were concerned that the coolant water let into the sea from the reactors might affect marine life. Besides, the local population feared that th e drawal of water from the Pechipara dam for the requirements of the plant and the township would deplete the availability of water for their irrigation and drinking water needs.

DAE officials, however, dismiss all fears. Top officials of the Health, Safety and Environment Group at the Bhabha Atomic Research Centre (BARC) say that Environmental Survey Laboratories (ESL) are open to the public and the data they collect are in the public domain. The officials say that when heavy water leaked into the reactor vault of the second unit at the Madras Atomic Power Station (MAPS), Kalpakkam, on March 26, 1999 (Frontline, April 23) details about the amount of heavy water that had leaked (and the fact that it was coolant heavy water that had leaked), the extent of tritium released and the number of workers affected were made available to the press.

As for the issue of decommissioning, DAE officials said that the department had "broadbased experience" in this area. A dedicated group had studied the decommissioning prerequisites and made detailed plans for Indian plants. According to these officials, decommissioning costs account for less than two per cent of the project cost and they were factored into the tariff.

Man-rem exposures were less than 0.1 per cent of those caused by natural background radiation.

The DAE, the officials said, had expertise in both liquid and solid waste management. High-level solid waste would be stored in deep repositories in locations where it would not come into contact with ground water. It would be vitrified in the form of gl ass, and any leaching of plutonium from glass would be negligible even over thousands of years.

At Kaiga, the reactor plant, the buildings and other facilities occupied only about 25 hectares of a total of 120 ha of forest land that was acquired. Compensatory afforestation was undertaken, and when academics from Mangalore University, who set up a n ursery at Kaiga, studied the flora and fauna of the area, they discovered some rare species of plants, which the DAE was preserving.

At Kudangulam, the DAE officials said, the entire area acquired was uninhabited. The local fishermen were given assurances that no radioactive substance would be let into the sea, and that the coolant water let into the sea would not affect fish life the re. Only 120 mcft of water a year would be drawn from the Pechipara dam: this would form only about 0.6 per cent of its annual yield of 14,500 mcft, and according to the officials, this will not affect local irrigation interests in any way.

This article is closed for comments.
Please Email the Editor