Ingozi Yenuzi yaseFukushima: Izinga le-Tritium emanzini ahlanzekile angaphansi komkhawulo wokusebenza wase-Japan  

I-International Atomic Energy Agency (IAEA) ikuqinisekisile ukuthi izinga le-tritium eqoqweni lesine lokwelashwa okuhlanjululwe. amanzi, i-Tokyo Electric Power Company (TEPCO) eqale ukuyikhipha ngomhla ka-28 February 2024, ingaphansi kakhulu kunomkhawulo wokusebenza wase-Japan. 

Ochwepheshe abamiswe endaweni ye-Fukushima nyukliya amandla isiteshi (i-FDNPS) sithathe amasampula ngemuva kokwelashwa amanzi yahlanjululwa nge amanzi olwandle ezikhungweni zokukhulula ngomhlaka-28 February. Ukuhlaziywa kuqinisekisile ukuthi ukugcwala kwe-tritium kungaphansi kakhulu komkhawulo wokusebenza wama-becquerel ayi-1,500 ilitha. 

I-Japan ikhipha ukwelashwa amanzi kusuka ku-FDNPS ngamaqoqo. Amaqoqo amathathu adlule - isamba esingu-23,400 cubic metres amanzi - ziphinde zaqinisekiswa yi-IAEA ukuthi iqukethe ukugxila kwe-tritium ngaphansi kakhulu kwemikhawulo yokusebenza. 

Kusukela kwenzeka ingozi ngo-2011, amanzi kuyadingeka ukuze kuphole njalo uphethiloli oncibilikisiwe nemfucumfucu kaphethiloli e-Fukushima Daiichi NPS. Ngaphezu kwe- amanzi empontshelwa le njongo, amanzi angaphansi komhlaba nawo angena esizeni esuka endaweni ezungezile, futhi amanzi emvula awela esikhungweni se-reactor esilimele kanye nezakhiwo zomoya. Nini amanzi ihlangana nophethiloli oncibilikisiwe, udoti kaphethiloli nezinye izinto ezikhipha imisebe, ingcoliswa. 

Okungcolisiwe amanzi is waphathwa ngenqubo yokuhlunga eyaziwa ngokuthi I-Advanced Liquid Processing System (ALPS) esebenzisa uchungechunge lokusabela kwamakhemikhali ukususa ama-radionuclide angama-62 emanzini angcolile ngaphambi kokugcinwa. Nokho, i-tritium ayikwazi ukusuka emanzini angcolile nge-ALPS. I-Tritium ingatholwa uma igxiliswe kakhulu emanzini amancane, isibonelo ku- nyukliya izinsiza ze-fusion. Kodwa-ke, amanzi agciniwe e-Fukushima Daiichi NPS ane-concentration ephansi ye-tritium kumthamo omkhulu wamanzi ngakho-ke ubuchwepheshe obukhona abusebenzi. 

I-Tritium iwuhlobo lwe-hydrogen olukhipha imisebe engokwemvelo (uhhafu wempilo engu-12.32) olukhiqizwa emkhathini lapho imisebe ye-cosmic ingqubuzana nama-molecule omoya futhi inomthelela ophansi kakhulu we-radiological wawo wonke ama-radionuclide avela ngokwemvelo emanzini olwandle. I-Tritium iphinde ibe ngumkhiqizo wokusebenza nyukliya izimboni zamandla ukukhiqiza ugesi. Ikhipha izinhlayiya ze-beta ezibuthakathaka, okungukuthi, ama-electron, anesilinganiso samandla angu-5.7 keV (kiloelectron-volts), angangena cishe u-6.0 mm womoya kodwa angakwazi ukungena emzimbeni ngesikhumba somuntu. Ingase yethule ingozi yokukhishwa kwemisebe uma ihogeliwe noma idliwe kodwa iyingozi kuphela kubantu ngemithamo emikhulu kakhulu. 

Njengamanje, amanzi angcolile akhiqizwa eFukushima Daiichi NPS ayaphathwa futhi agcinwe esizeni emathangeni alungiselelwe ngokukhethekile. I-TEPCO, umqhubi wendawo, ufake cishe i-1000 yalawa mathangi endaweni ye-Fukushima Daiichi NPS ukuze abambe cishe ama-cubic metres ayizigidi eziyi-1.3 wamanzi ahlanzekile (kusukela zi-2 Juni 2022). Kusukela ngo-2011, umthamo wamanzi endaweni yokugcina uye wanda kancane kancane, kanye nethangi lamanje isikhala atholakalayo ukugcina la manzi asezogcwala.  

Nakuba kwenziwe ukuthuthukiswa ukuze kuncishiswe kakhulu izinga okukhiqizwa ngalo amanzi angcolile, i-TEPCO inqume ukuthi isixazululo sesikhathi eside sokulahlwa siyadingeka ukuze isize ukuqinisekisa ukuyekwa okuqhubekayo kwesiza. Ngo-Ephreli 2021, uHulumeni wase-Japan wakhipha Inqubomgomo Yakhe Eyisisekelo echaza isiqondiso sokulahla amanzi ane-ALPS ngokusebenzisa ukuthululwa okulawulwayo olwandle okuzoqalwa cishe eminyakeni emi-2, kuncike ekugunyazweni kokulawula kwasekhaya. 

Ngomhla ziyi-11 kuNdasa 2011, iJapan yanyakaziswa yiGreat East Japan (Tohoku) Ukuzamazama komhlaba. Yalandelwa yi-tsunami eyaholela ekubeni amagagasi afinyelele ubude obungaphezu kwamamitha ayi-10. I ukuzamazama komhlaba kanye ne-tsunami yaholela engozini enkulu eFukushima Daiichi Nuclear Isiteshi Samandla, esagcina sahlukaniswa njengeZinga lesi-7 kuMazwe ngamazwe Nuclear kanye ne-Radiological Event Scale, izinga elifanayo ne-Chernobyl yango-1986 ingozi nokho imiphumela yezempilo yomphakathi eFukushima mibi kakhulu. 

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Imithombo:  

1. I-IAEA. Ukukhishwa kwabezindaba – Izinga le-Tritium lingaphansi kakhulu komkhawulo wokusebenza wase-Japan kuqoqo lesine lamanzi ahlanzekile e-ALPS, kuqinisekisa i-IAEA. Ibuyiselwe mhlaka 29 February 2024. https://www.iaea.org/newscenter/pressreleases/tritium-level-far-below-japans-operational-limit-in-fourth-batch-of-alps-treated-water-iaea-confirms  

2. I-IAEA. I-Fukushima Daiichi ALPS Ukukhipha Amanzi Aphathwe. I-Advanced Liquid Processing System (ALPS). https://www.iaea.org/topics/response/fukushima-daiichi-nuclear-accident/fukushima-daiichi-alps-treated-water-discharge 

3. I-IAEA. Ingozi Yenuzi yaseFukushima Daiichi https://www.iaea.org/topics/response/fukushima-daiichi-nuclear-accident  

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