I-Arhente yaMandla eAtomic yaMazwe ngaMazwe (IAEA) iqinisekisile ukuba inqanaba le-tritium kwibhetshi yesine ye-diluted enyangweni. amanzi, apho iTokyo Electric Power Company (TEPCO) iqale ukuyikhupha nge-28 February 2024, ingaphantsi kakhulu kumda wokusebenza waseJapan.
Iingcali ezimise kwindawo yeFukushima nyukliya amandla isikhululo (FDNPS) sathatha iisampuli emva kokunyangwa amanzi yaxutywa nge Amanzi olwandle kwiindawo zokukhuphela nge-28 kaFebruwari. Uhlalutyo luqinisekisile ukuba i-tritium concentration ingaphantsi kakhulu kumda wokusebenza we-1,500 becquerels ilitha nganye.
IJapan ikhupha unyango amanzi ukusuka kwi-FDNPS kwiibhetshi. Iibhetshi ezintathu zangaphambili - iyonke yi-23,400 cubic metres ye amanzi -kwaye kwaqinisekiswa yi-IAEA ukuba iqulathe ugxininiso lwe-tritium ngaphantsi kwemida yokusebenza.
Ukusukela oko kwenzeka ingozi ngo-2011, amanzi iyafuneka ngokuqhubekayo ukupholisa isibaso esinyibilikisiweyo kunye nenkunkuma yamafutha kwi-NPS ye-Fukushima Daiichi. Ukongeza kwi amanzi ukumpontshelwa le njongo, amanzi aphantsi komhlaba nawo ayangena kwisiza esuka kwindawo engqongileyo, kwaye amanzi emvula awela kwireactor eyonakeleyo kunye nezakhiwo zomoya. Nini amanzi idibana ne-fuel enyibilikisiweyo, inkunkuma yamafutha kunye nezinye izinto ze-radioactive, ingcoliseka.
Eyosuleleneyo amanzi is baphathwa ngenkqubo yokuhluza eyaziwa ngokuba yi-Advanced Liquid Processing System (ALPS) esebenzisa uthotho lweekhemikhali zokusabela ukususa ama-radionuclides angama-62 kumanzi angcolisekileyo phambi kokuba agcinwe. Nangona kunjalo, i-tritium ayinakusuka kumanzi angcolileyo nge-ALPS. I-Tritium inokufunyanwa kwakhona xa igxininiswe kakhulu kumlinganiselo omncinci wamanzi, umzekelo nyukliya izibonelelo zokudibanisa. Nangona kunjalo, amanzi agciniweyo kwi-NPS ye-Fukushima Daiichi ine-concentration ephantsi ye-tritium kumthamo omkhulu wamanzi kwaye ngoko ke ubugcisa obukhoyo abusebenzi.
I-Tritium luhlobo lwe-radioactive lwe-hydrogen oluvele ngokwendalo (isiqingatha sobomi beminyaka eyi-12.32) eveliswa kwi-atmosfera xa imitha ye-cosmic ingqubana neemolekyuli zomoya kwaye ineempembelelo zeradiological ezisezantsi kuzo zonke ezenzeka ngokwendalo iiradionuclides emanzini olwandle. I-Tritium ikwayimveliso yemveliso yokusebenza nyukliya amaziko ombane ukuvelisa umbane. Ikhupha ii-beta-particles ezibuthathaka, oko kukuthi, ii-electron, kunye namandla aphakathi kwe-5.7 keV (i-kiloelectron-volts), enokungena malunga ne-6.0 mm yomoya kodwa ayikwazi ukungena emzimbeni ngolusu lomntu. Isenokubonisa ingozi yokusasazeka kwemitha ukuba irholiwe okanye ityiwe kodwa iyingozi kuphela ebantwini kwiidosi ezinkulu kakhulu.
Okwangoku, amanzi angcolileyo aveliswa kwi-NPS ye-Fukushima Daiichi ayaphathwa kwaye agcinwe kwisiza kwiitanki ezilungiselelwe ngokukodwa. I-TEPCO, umsebenzisi weplanti, ufakele malunga ne-1000 yala matanki kwindawo ye-NPS ye-Fukushima Daiichi ukubamba malunga ne-1.3 yezigidi ze-cubic metres zamanzi acociweyo (ukusukela nge-2 Juni 2022). Ukususela ngo-2011, umthamo wamanzi kwindawo yokugcina unyuke ngokukhawuleza, kunye netanki yangoku isithuba akhoyo ukugcina la manzi sele esondele kumthamo opheleleyo.
Ngelixa uphuculo lwenziwe ukunciphisa kakhulu isantya sokwenziwa kwamanzi angcolisekileyo, i-TEPCO imisele isisombululo sokulahlwa kwexesha elide siyafuneka ukuze kuqinisekiswe ukupheliswa okuqhubekayo kwesiza. Ngo-Epreli ka-2021, uRhulumente wase-Japan ukhuphe uMgaqo-nkqubo wakhe oSisiseko ochaza isikhokelo sokulahla amanzi acociweyo e-ALPS ngokukhutshelwa ngokulawulwayo elwandle ukuze aqaliswe malunga neminyaka emi-2, ngokuxhomekeke kwimvume yolawulo lwasekhaya.
Ngomhla we-11 kuMatshi ka-2011, iJapan yashukunyiswa yiGreat East Japan (Tohoku) Ukuzamazama komhlaba. Yalandelwa yitsunami eyakhokelela ekubeni amaza afikelele ukuphakama ngaphezu kweemitha ezili-10. I inyikima kunye netsunami yakhokelela kwingozi enkulu eFukushima Daiichi Nyukliya Isitishi saMandla, esathi ekugqibeleni sahlelwa njengeNqanaba lesi-7 kuMazwe ngaMazwe Nyukliya kunye neRadiological Event Scale, inqanaba elifanayo neChernobyl ka-1986 ingozi nangona kunjalo iziphumo zempilo yoluntu eFukushima zincinci kakhulu.
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Imithombo:
- IAEA. Ukukhutshwa kweendaba - inqanaba le-Tritium kude kakhulu kumda wokusebenza waseJapan kwibhetshi yesine yamanzi acociweyo e-ALPS, iqinisekisa i-IAEA. Ithunyelwe nge-29 kaFebruwari 2024. https://www.iaea.org/newscenter/pressreleases/tritium-level-far-below-japans-operational-limit-in-fourth-batch-of-alps-treated-water-iaea-confirms
- IAEA. I-Fukushima Daiichi ALPS eNyangelwe ukukhutshwa kwamanzi. Inkqubo ekwinqanaba eliphezulu loLungiselelo lwamanzi (ALPS). https://www.iaea.org/topics/response/fukushima-daiichi-nuclear-accident/fukushima-daiichi-alps-treated-water-discharge
- IAEA. Ingozi yeNyukliya yaseFukushima Daiichi https://www.iaea.org/topics/response/fukushima-daiichi-nuclear-accident
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