5.10) Dummy Fuel
Dummy Fuel is used to simulate the Nuclear Fuel Assembly, both by geometrical and by weight consideration. Dummy Fuel is made of lead encapsulated in steel tubes and has no radioactive material.
These are required to be installed in the reactor during commissioning, to study hydraulic characteristics like pressure and temperature variations, flow pattern with various combinations of Reactor Coolant Pumps, temperature etc., in the Primary Coolant System.
The Dummy Fuel assemblies have no problems of disposal as they are non‐radioactive, but in fact are preserved and re‐used in subsequent new reactors during commissioning test.
5.11) Fuel Supply
Fuel for initial and reload of Unit‐1&2 of KKNPP is procured as per Fuel Contract signed between Russian Federation Russia
The finished fuel assemblies are packed in specially designed casks and transported by special air craft from Russia to India Russia
5.12) Fresh Water Supply
Desalination plant, based on Mechanical Vapour Compression technology, at KKNPP site has been designed to meet the process requirements of Unit # 1&2 and the potable water requirements.
The plant water requirement is 5664 m3/day and the potable water requirement is 1272 m3/day. Against this, the installed desalination plant capacity is 7680m3/day. This is met by three units, each of capacity 2560 m3/day, with one additional unit of 2560 m3/day unit, as a standby. The output water from the desalination plant is further purified by demineralizing and used for industrial purpose. The product water is treated further for making it potable water.
The provision of water storage and inventory available in various tanks are adequate for cooling requirements of Reactor Plant for at least ten days, in case of power failure from the Grid (even though the regulatory requirement is only 7 days).
5.13) Other Water Sources
The desalination plants have been designed for sufficient capacity and have been erected and commissioned. Hence, the question of water utilization from other sources such as Pechiparai dam and Tamirabharani river does not arise.
5.14) Desalination Plants
Desalination Plant at KKNPP site is based on thermal desalination i.e Mechanical Vapour Compression (MVC) system. The system draws sea water from the main cooling water intake channel provided for the power plant. The brine reject from the desalination plant will be mixed with the condensed cooling water discharges, diluted and released into the sea through the existing outfall channel.
A base line environmental assessment and mathematical modeling study on flow, dispersion of brine reject and extent of mixing in the sea has been done by Indomer Coastal Hydraulics Pvt Ltd, Chennai, who is a certified consultant by Ministry of Agriculture, Department of Animal Husbandry & Dairying, New Delhi and also a certified ‘A’ grade hydrographic surveyor by Inland Waterways Authority of India, Noida.
The brine reject volume is 350 m3/ hour and it gets diluted with sea water discharge through the outlet canal which is 2,50,000 m3/hour during plant normal operation. This will give an initial dilution of the order 700. This pre‐dilution would reduce the brine concentration from 69 ppt to an ambient value of 35.1 ppt.
The brine reject will not have any impact in the marine environment while joining the sea.
The brine reject does not contain any toxic or organic pollutant.
5.15) Environmental Impact of Desalination Plants
This is covered at 5.14) above.
5.16) Nuclear Waste Management
The origin of radioactivity in a reactor is the fuel that is undergoing irradiation/ fission. The fuel is clad in a metallic tube so all the radioactivity produced in the fuel stays within the fuel tube or clad. In the unlikely event of any pinhole leak from the fuel tube, radioactivity could come into contact with the circulating coolant water which is constantly being recirculated through the core of the reactor for removal of heat, produced by fission.
1.1 If any radioactivity enters the primary cooling water circuit, it is effectively removed by Filters and Ion‐Exchange columns provided in the circuit. As the primary cooling water circuit in KKNPP is a closed cycle, any radioactivity that escaped from the fuel gets trapped in Filters and Ion Exchangers and would not pose any hazard to either plant or personnel and there is no way it can find its way to environment. Other liquid process effluents are evaporated for an extremely high decontamination, rendering the condensate with insignificant contamination, considered fit for reuse in the plant and the concentrates are concreted to result in a stable matrix for safe storage and subsequent disposal
1.2 Similarly if any solid wastes get contaminated with radioactivity, they are carefully collected and as a first step volume of the wastes produced are reduced to a small fraction by treatment methods like incineration and compaction, apart from size reduction; then the wastes are conditioned by being fixed in cement concrete before they are stored safely for an interim period, .They would be considered for disposal in a Near Surface Disposal Facility, in a few years time, giving adequate time for decay of short‐lived radioactivity.
1.3 Any radioactivity, in the exhaust air system from the reactor buildings, though insignificant is invariably treated through a series of off‐gas clean up system, before release through tall stacks.
1.4 Due to the total containment of all radioactivity in the fuel tube, the type of wastes that result from various systems in this reactor are essentially low level wastes, with a small quantity of intermediate level wastes. There are no high level wastes associated with the operation of the reactors at Kudankulam
1.5 Thus, as a matter of abundant caution and abiding concern for safety of environment and members of Public, a number of state‐of‐the art technologies are employed in the Safe Management of Radioactive Wastes. The track record of DAE in this regard has been exemplary over the past four decades, and compares favourably with the best in the world.
2.0 Spent fuel: First and foremost it should be remembered that Spent Fuel is not a waste in the Indian Nuclear Programme. A closed fuel cycle is followed, where the valuable fissile materials like Uranium and Plutonium which are present in the Spent Fuel are recovered for reuse.
2.1 Spent fuel is therefore an asset that needs to be preserved. At Kudankulam, Spent Fuel from the Reactors will be carefully stored in Storage Pools, which are always filled with pure, demineralized, borated water which is constantly recirculated. These pools are highintegrity concrete pools which are additionally lined with stainless steel sheets, to ensure effective containment for extended periods of time. The Department of Atomic Energy has long experience and expertise of a high order in the safe management of Spent Fuel
2.2 There is no plan to do the reprocessing of the Spent Fuel at Kudankulam site. As such the storage of Spent Fuel at Kudankulam is to be considered only as an interim measure till they are transported to a Reprocessing Facility.
2.3 Adequate Technology and years of experience are available with Department of Atomic Energy for transporting Spent Fuel from one site to another through both Railways and by roadways, in a safe manner without any public hazard. This is done as per stipulations of AERB, regarding Transport Regulations that govern safety.
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