ISSN (Print) - 0012-9976 | ISSN (Online) - 2349-8846

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Playing Fast and Loose

Playing Fast and Loose THE accident at Tarapur when radioactive water found its way into the storm-water drain at the waste immobilisation plant is, according to the chief of the Atomic Energy Regulatory Board (AERB), a negligible incident. "On the international nuclear events scale the incident rates well below zero. The total radiation dose was well below 100 millicuries." Further, while routine checks had shown an increase in radioactivity in March, only in April was it considered to be statistically significant. The contamination took place because of "two unlucky things"; one, a pipe which carries steam under pressure and passes through radioactive waste and is open to radioactive contamination leaked at a joint and, two, the dilution tank designed to be an extra precaution against leakage of radioactive water had been eliminated at the construction stage. And why did the department wait for the leak to be revealed by the press and not take steps itself to inform the public when the leak occurred,? "We fell there was no need to make a public announcement because we took care of the leak appropriately." This entire episode illustrates very well the extraordinary falitude that has been allowed to the atomic energy department and the nuclear industry in matters which ought to come under public scrutiny. First, a pipe which goes through radioactive material necessarily exposes its contents to radioactivity, which means that the steam passing through it becomes radioactive, even if to a small degree. Such a system must be considered a primary loop and must logically be a closed one, to be discharged periodically and treated. This is expensive and the amount of radioactive contamination in the steam-pipes was apparently not considered to be high enough to require this sort of handling. The alternative adopted was to minimise the radioactivity released by diluting the condensed steam. This is done, according to the department, through dilution tanks, which are therefore essential. That one of the steam pipes led directly to the storm-water drain because those responsible for construction had dispensed with the dilution tank for whatever reason is not simply a construction flaw. It is a serious technical and safety lapse which ought to be the subject of a high-level probe. Second, one may even question whether the method adopted for treating the radioactive waste was indeed the best or whether it was simply the cheapest. Third, the fact that a critical pipe joint or joints developed a leak is, to anyone familiar with pipe design, incomprehensible. For, critical joints even in chemical plants which do not handle radioactive material arc subject to a series of tests to establish the integrity of the pipe system and the material used, such as pressure tests, non-destructive tests like radiographic and ultrasonic scrutiny, and so on. This being a critical service the entire system should, following the usual practice in the chemical industry, have been tested. This would have revealed flaws which eventually developed into doles'. This clearly was not done and the AERB has chosen to gloss over the lapse. Ironically, BARC itself sells these testing services to industry. Further, the department spokesperson's claim that the leaks occurred due to corrosion is again unacceptable for the design of such sensitive piping systems normally requires that allowance is provided for material deterioration due to corrosion when determining the thickness of the pipes. The point is that in any other chemical plant there would have been checks at various levels prompted by various concerns the interests of the owners of the industry, the consultants responsible for the design, the construction firm or department, each wanting to safeguard itself against possible accidents later on. While even these checks fail sometimes and, of course, they often delay processes, they do overall contribute to better design, construction and safety standards.

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