partially closed cycle. In open cycle, the SNF is considered as high-level waste and
disposed in a safe storage facility without going through any chemical processes to
mitigate its radiotoxicity. The SNF is supposed to be remained in that situation for
millions of years until it gives off its radiotoxicity naturally and transforms itself into
safe uranium levels. While in case of closed cycle, much of SNF is reprocessed to
extract uranium and plutonium. It is estimated that around 94–96% of uranium and
1–1.5% of plutonium can be recycled from its original SNF quantity to be used as a
nuclear fuel, and rests are disposed. Different strategies or technologies are used in
different countries to recycle the SNF in closed cycle process.
The final disposal of nuclear wastes from various processes of nuclear fuel cycles
should end up in a deep geological repository (DGR), but as of now, there is none
operating but under process. The safety of DGR is very much debated but in many
international forums it has been accepted as an option for recent time until new
strategies arise for better disposal option. For current measures, low and intermediate
levels of wastes are buried close to surface but high levels of wastes are disposed of
to an underground engineered facility for its radioactivity to decay naturally. The
time taken for nuclear wastes in safe storage repositories to reach to its safe levels
depends much on its reprocessing technologies.
Radioactive wastes may generate from NFC during or between various stages of
characterization, segregation, treatment, transport and disposal. Radioisotopes like
89Sr, 90Y, 95Zr, 103Ru, 105Rh, 129Te, 140Ba, 144Ce, 144Pr and their relevant
isotopes are considered as significant hazards at reactor stage and may get released
into environment. Apart from that, during fuel element transport and fuel
reprocessing state, 90Sr, 129Te, 131I, 137Cs, 95Zr, 95Nb, 106Ru, 144Ce or their
other relevant radioisotopes may also get released. Contamination may also happen
during solidification of fusion product and final disposal process. The content of final
disposal from NFC may get leeched in repository and contaminate the soil mostly
with radionuclides like 137Cs, 90Sr and actinides (Smičiklas and Šljivić-Ivanović
2016).
13.1.3 Radioactive Wastes from Medicine
Radioisotopes are increasingly used in health care for therapeutic and diagnostic
purposes. The radioisotopes which are mostly used include Technetium 99m
(Tc-99m), Iodine 131 (I-131), Iodine 125 (I-125), Iodine 123 (I-123), Tritium
3 (H-3), Carbon 14 (C-14), Yttrium 90 (Y-90), Cobalt 60 (Co-60), Strontium
89 (Sr-89), Iridium 192 (Ir-192), Caesium 137 (Cs-137), Xenon 133 (Xn-133), etc.
The department of nuclear medicine in each hospital generates most of the radioactive wastes. The radioactive wastes are mostly in the form of liquid with little solid
wastes as used in syringes, needles, vials, contaminated gloves, cotton swabs,
clothing, absorbent materials and utensils of patients and minimal amount of gaseous
products. Strategies used in disposal of radioactive wastes in hospitals involves safe
storage until its radioactivity is reduced to safe levels naturally through decaying and
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U. K. Vandana et al.
disposed in a safe storage facility without going through any chemical processes to
mitigate its radiotoxicity. The SNF is supposed to be remained in that situation for
millions of years until it gives off its radiotoxicity naturally and transforms itself into
safe uranium levels. While in case of closed cycle, much of SNF is reprocessed to
extract uranium and plutonium. It is estimated that around 94–96% of uranium and
1–1.5% of plutonium can be recycled from its original SNF quantity to be used as a
nuclear fuel, and rests are disposed. Different strategies or technologies are used in
different countries to recycle the SNF in closed cycle process.
The final disposal of nuclear wastes from various processes of nuclear fuel cycles
should end up in a deep geological repository (DGR), but as of now, there is none
operating but under process. The safety of DGR is very much debated but in many
international forums it has been accepted as an option for recent time until new
strategies arise for better disposal option. For current measures, low and intermediate
levels of wastes are buried close to surface but high levels of wastes are disposed of
to an underground engineered facility for its radioactivity to decay naturally. The
time taken for nuclear wastes in safe storage repositories to reach to its safe levels
depends much on its reprocessing technologies.
Radioactive wastes may generate from NFC during or between various stages of
characterization, segregation, treatment, transport and disposal. Radioisotopes like
89Sr, 90Y, 95Zr, 103Ru, 105Rh, 129Te, 140Ba, 144Ce, 144Pr and their relevant
isotopes are considered as significant hazards at reactor stage and may get released
into environment. Apart from that, during fuel element transport and fuel
reprocessing state, 90Sr, 129Te, 131I, 137Cs, 95Zr, 95Nb, 106Ru, 144Ce or their
other relevant radioisotopes may also get released. Contamination may also happen
during solidification of fusion product and final disposal process. The content of final
disposal from NFC may get leeched in repository and contaminate the soil mostly
with radionuclides like 137Cs, 90Sr and actinides (Smičiklas and Šljivić-Ivanović
2016).
13.1.3 Radioactive Wastes from Medicine
Radioisotopes are increasingly used in health care for therapeutic and diagnostic
purposes. The radioisotopes which are mostly used include Technetium 99m
(Tc-99m), Iodine 131 (I-131), Iodine 125 (I-125), Iodine 123 (I-123), Tritium
3 (H-3), Carbon 14 (C-14), Yttrium 90 (Y-90), Cobalt 60 (Co-60), Strontium
89 (Sr-89), Iridium 192 (Ir-192), Caesium 137 (Cs-137), Xenon 133 (Xn-133), etc.
The department of nuclear medicine in each hospital generates most of the radioactive wastes. The radioactive wastes are mostly in the form of liquid with little solid
wastes as used in syringes, needles, vials, contaminated gloves, cotton swabs,
clothing, absorbent materials and utensils of patients and minimal amount of gaseous
products. Strategies used in disposal of radioactive wastes in hospitals involves safe
storage until its radioactivity is reduced to safe levels naturally through decaying and
332
U. K. Vandana et al.