SL-1 - SL-1

SL-1 yadroviy eritmasi
AQSh AEC SL-1.JPG
1961 yil 29-noyabr: SL-1 reaktor kemasi kabi harakat qilgan reaktor binosidan olib tashlanmoqda qamoqxona binosi zamonaviy yadro inshootlarida ishlatiladi. 60 tonna Manitovok Model 3900 kranida operatorni himoya qilish uchun 9,25 dyuym (23 sm) qalinlikdagi qo'rg'oshin oynali oynasi bo'lgan 5,25 dyuymli (13,3 sm) po'lat qalqon bor edi.
Sana1961 yil 3-yanvar
ManzilMilliy reaktor sinov stantsiyasi, Aydaho sharsharasi, Aydaho (hozir Aydaho milliy laboratoriyasi )
Koordinatalar43 ° 31′05 ″ N. 112 ° 49′24 ″ V / 43.518 ° N 112.8234 ° Vt / 43.518; -112.8234Koordinatalar: 43 ° 31′05 ″ N. 112 ° 49′24 ″ V / 43.518 ° N 112.8234 ° Vt / 43.518; -112.8234
NatijaINES 4-daraja (mahalliy oqibatlarga olib keladigan avariya)
O'limlar3
SL-1 Aydaho shtatida joylashgan
SL-1
SL-1
Joylashuv: Aydaho, g'arbiy Aydaho sharsharasi

The SL-1, yoki Statsionar kam quvvatli birinchi reaktor, edi a Amerika Qo'shma Shtatlari armiyasi eksperimental atom reaktori ichida Qo'shma Shtatlar sodir bo'lgan a bug 'portlashi va erish 1961 yil 3-yanvarda uchta operatorini o'ldirdi.[1][2][3][4] To'g'ridan-to'g'ri sabab markazning noto'g'ri olib qo'yilishi edi boshqaruv tayoqchasi, reaktor yadrosidagi neytronlarni yutish uchun javobgardir. Ushbu voqea AQSh tarixidagi zudlik bilan o'limga olib kelgan yagona reaktor avariyasi hisoblanadi.[5] Hodisa 80 ga yaqin odamni ozod qildi kurilar (3.0 TBq ) ning yod-131,[6] uzoq cho'lda joylashganligi sababli muhim deb hisoblanmagan Aydaho sharqida. Taxminan 1100 kuryer (41 TBq) ning bo'linish mahsulotlari atmosferaga chiqarildi.[7]

Joylashgan bino Milliy reaktor sinov stantsiyasi (NRTS) g'arbiy qismdan qirq milya (65 km) Aydaho sharsharasi, Aydaho, qismi edi Armiya atom energiyasi dasturi va loyihalash va qurish bosqichida Argonne Low Power Reactor (ALPR) sifatida tanilgan. Bu kichik, uzoqdagi harbiy ob'ektlarni, masalan, radar joylarini elektr energiyasi va issiqlik bilan ta'minlashga mo'ljallangan edi Arktika doirasi va unda bo'lganlar DEW liniyasi.[8] Dizayn quvvati 3 ga teng edi MW (issiqlik ),[9] ammo baxtsiz hodisadan bir necha oy oldin ba'zi 4,7 MVt sinovlar o'tkazildi. Ishlash quvvati 200 edi kVt elektr va kosmik isitish uchun 400 kVt quvvatli termal.[9]

Voqea paytida asosiy quvvat darajasi 20 ga etdi GW faqat to'rt millisekundada, bug 'portlashini tezlashtiradi.[10][11][12][13]

Dizayn va operatsiyalar

1954 yildan 1955 yilgacha AQSh armiyasi ularning chekka mintaqalarida ishlaydigan atom reaktori zavodlariga bo'lgan ehtiyojlarini baholadi. Arktika. Reaktorlar dizel generatorlari va armiyaning radiolokatsion stansiyalarini elektr energiyasi va issiqlik bilan ta'minlaydigan qozonlarni almashtirishlari kerak edi. Armiya reaktorlari bo'limi loyiha bo'yicha ko'rsatmalarni tuzdi va shartnoma tuzdi Argonne milliy laboratoriyasi (ANL) loyihalashtirish, qurish va prototipli reaktor stantsiyasini sinovdan o'tkazish uchun Argonne past quvvatli reaktor (ALPR).[14]

Ba'zi muhim mezonlarga quyidagilar kiritilgan:

  • Barcha komponentlar havo orqali tashilishi mumkin[9]
  • Barcha komponentlar 7,5 dan 9 20 fut (2,3 m × 2,7 m × 6,1 m) va og'irligi 20,000 funt (9,100 kg) bo'lgan paketlar bilan cheklangan.[9]
  • Standart komponentlardan foydalanish
  • Joyda minimal qurilish[9]
  • Oddiylik va ishonchlilik[9]
  • Arktikaning "doimiy muzli mintaqasi" ga moslashuvchan[9]
  • Har bir yadro uchun 3 yillik yoqilg'ining ishlash muddati[14][9]

Prototip NRTS saytida 1957 yil iyuldan 1958 yil iyulgacha qurilgan. 1958 yil 11 avgustda juda muhim bo'lgan,[14] 24 oktyabrda ish boshladi va 1958 yil 2 dekabrda rasmiy ravishda bag'ishlandi.[14] 3 MVt (termal) qaynoq suv reaktori (BWR) 93,20% ishlatilgan yuqori darajada boyitilgan uran yoqilg'i.[15] U bilan ishlagan tabiiy aylanish, sovutish suyuqligi sifatida engil suvdan foydalaning (va boshqalar). og'ir suv ) va moderator. ANL o'z tajribasidan foydalangan BORAX tajribalari BWRni loyihalash uchun. Aylanma suv tizimi uran-alyuminiy qotishmasining yonilg'i plitalari orqali oqib o'tadigan kvadrat dyuym (2100 kPa) uchun 300 funt sterling bilan ishladi. Zavod 1958 yil dekabr oyida keng ko'lamli sinovlardan so'ng o'qitish va ishlash tajribasi uchun AQSh armiyasiga topshirildi Yonish muhandisligi Birlashtirilgan (CEI) 1959 yil 5-fevraldan boshlab bosh pudratchi sifatida ishlaydi.[16]

CEI SL-1 reaktorining haqiqiy ishlashi, harbiy kadrlarni muntazam o'qitish va rivojlanish tadqiqot dasturlari uchun javobgardir.

Pudratchi saytga loyiha menejeri, operatsiyalar bo'yicha nazoratchi, sinov rahbari va taxminan olti kishidan iborat texnik xodimlarni taqdim etdi. So'nggi oylarda Loyiha menejeri bu erda taxminan yarim soatni va Konnektikutdagi pudratchining ofisida o'tkazdi. U yo'q bo'lganda, operatsiyalar bo'yicha nazoratchi yoki test nazoratchisi loyiha menejeri etib tayinlangan.

... Kengash oldidagi guvohliklardan ko'rinib turibdiki, odatiy bo'lmagan ish olib borilayotganda CEI har qanday smenada nazoratni amalga oshiradi.

... AEC ning Aydaho idorasi va armiya reaktorlari idorasi tungi nazoratchilarning qo'shilishi faqat odatdagi ishlarga jalb qilingan bo'lsa, reaktorni mavjud tartibda ishlatish maqsadining bir qismini, ya'ni zavod bilan ishlash tajribasini olish bilan bartaraf etishiga ishongan. faqat harbiy xizmatchilar.

— SL-1 hodisasi haqida hisobot, 1961 yil 3-yanvar, 6-7 betlar[17]

Armiya reaktorlarini tayyorlash dasturida tinglovchilar orasida AQSh armiyasining chaqirilgan a'zolari bor edi kadrlar, asosan, zavod operatorlari bo'lganlar, garchi ko'plab "dengiz" fuqarolari (qarang) NS Savana ) AQSh havo kuchlari va AQSh dengiz kuchlarining bir nechta xodimlari bilan birgalikda o'qitilgan.[16] Zavodning ishlashi odatda tomonidan bajarilgan bo'lsa-da kadrlar ikki kishilik ekipajlarda reaktorning har qanday rivojlanishi to'g'ridan-to'g'ri CEI xodimlari tomonidan boshqarilishi kerak edi. CEI yaqinda 1960 yilning ikkinchi yarmida reaktor ustida ish olib borishga qaror qildi, unda reaktor 4,7 MVt quvvat bilan ishlaydi.issiqlik "PL-1 kondanser sinovi" uchun.[18] Reaktor yadrosi qarigan va bor "zahar "chiziqlar korroziyaga uchradi va yirtilib ketdi, CEI yadro tarkibidagi borning 18% ga yaqini" yo'qolgan "deb hisobladi. Natijada"kadmiy choyshab "(shuningdek," zahar "), voqea sodir bo'lishidan ikki oy oldin, 1960 yil 11-noyabrda. Bor zaharli chiziqlarining po'sti va / yoki korroziyasini yo'qotishi bo'yicha tuzatuv ishlari yaqinda[tushuntirish kerak ] yangi kadmiy varaqlari o'rnatiladigan reaktor yadrosiga o'tish "reaktorning yopilish chegarasini oshirish uchun bir nechta tee slot holatiga."[19] Ushbu o'zgartirish 1960 yil 15-noyabrda, voqea sodir bo'lishidan bir necha hafta oldin amalga oshirildi.

Voqea sodir bo'lganidan oldin ALPR. Silindr shaklidagi katta bino pastki qismida shag'alga singdirilgan yadro reaktorini, o'rtada asosiy ish joyini yoki ishchi qavatni va tepaga yaqin joylashgan kondensatorning fan xonasini ushlab turadi. Turli xil qo'llab-quvvatlash va ma'muriy binolar uni o'rab oladi.

Zavod uskunalarining aksariyati diametri 38,5 fut (11,7 m) bo'lgan silindrsimon po'lat reaktor binosida joylashgan bo'lib, umumiy balandligi 48 fut (15 m) bo'lgan.[9] ARA-602 deb nomlanuvchi reaktor binosi plastinka po'latdan yasalgan bo'lib, ularning aksariyati qalinligi 1/4 dyuym (6 mm) bo'lgan. Binoga kirish odatiy eshik orqali ARA-603, qo'llab-quvvatlash inshootlari binosining yopiq tashqi zinapoyasi orqali ta'minlandi. Favqulodda chiqish eshigi ham kiritilgan bo'lib, uning tashqi zinapoyasi zamin darajasiga ko'tarilgan.[9] Reaktor binosi, aholi punktlarida joylashgan reaktorlar uchun ishlatilgandek, bosim turidagi to'suvchi qobiq emas edi. Shunga qaramay, bino oxir-oqibat portlash natijasida chiqarilgan radioaktiv zarralarning ko'p qismini o'z ichiga olgan.

Reaktor yadrosi konstruktsiyasi 59 ta yonilg'i yig'ish moslamasi uchun qurilgan ishga tushirish neytron manbai yig'ish va 9 ta novda. Amaldagi yadro 40 ta yonilg'i elementiga ega va 5 ta xoch shaklidagi novda bilan boshqarilgan.[9] 5 ta faol tayoq kesmada plyus belgisi (+) shaklida bo'lgan: markazda 1 ta (tayoq raqami 9) va 4 ta faol yadro atroflarida (1, 3, 5 va 7 tayoqchalar).[9] Boshqarish tayoqchalari 60 mils (1,5 mm) qalin kadmiydan tayyorlangan, 80 mils (2,0 mm) alyuminiy bilan qoplangan. Ularning umumiy uzunligi 14 dyuym (36 sm) va samarali uzunligi 32 dyuym (81 sm) bo'lgan.[9] 40 ta yonilg'i to'plamlari har biri 9 ta yonilg'i plitalaridan iborat edi.[9] Plitalar 120 mils (3,0 mm) qalinlikda bo'lib, 50 mil (1,3 mm) uran-alyuminiy qotishmasidan iborat "go'sht" dan iborat bo'lib, X-8001 alyuminiy qoplamasi 35 mil (0,89 mm) bilan qoplangan.[9] Go'shtning uzunligi 25,8 dyuym (66 sm) va eni 3,5 dyuym (8,9 sm) edi. Yoqilg'i plitalari orasidagi suv oralig'i 310 mils (7,9 mm) ni tashkil etdi.[9] Boshqarish tayog'i kafanidagi suv kanallari 0,5 dyuym (13 mm) ni tashkil etdi. 40 ta montaj yadrosining dastlabki yuklanishi 93,2% uran-235 bilan yuqori darajada boyitilgan va U-235 tarkibidagi 31 funt (14 kg) ni o'z ichiga olgan.[9]

Kichikroq yoqilg'ini yuklashni qasddan tanlash markaz yonidagi hududni 59 yoqilg'i yig'ish vositalaridan ko'ra faolroq qildi. Sinovlar kerak emas degan xulosaga kelgandan so'ng, to'rtta tashqi boshqaruv tayoqchalari hatto kichik yadroda ham ishlatilmadi.[9][17] Ishlayotgan SL-1 yadrosida 2, 4, 6 va 8-sonli tayoqchalar qo'g'irchoq tayoqlar bo'lib, 1960 yil 11-noyabrdan keyin kadmiyum shillari bo'lgan yoki sinov datchiklari bilan to'ldirilgan va katta T harfiga o'xshash bo'lgan.[18] Yadro hajmini minimallashtirishga qaratilgan harakat markaziy tayoqqa g'ayritabiiy darajada katta reaktivlik berdi.

Baxtsiz hodisa va javob

1960 yil 21-dekabrda reaktor texnik xizmat ko'rsatish, asboblarni kalibrlash, yordamchi asboblarni o'rnatish va 44 ta oqim simlarini o'rnatish uchun o'chirildi neytron oqimi reaktor yadrosidagi darajalar. Simlar alyuminiydan yasalgan va tarkibida alyuminiy-kobalt shlyuzlari bo'lgan qotishma.

1961 yil 3-yanvarda ta'til davomida o'n bir kunlik yopilishdan so'ng reaktor qayta ishga tushirishga tayyorlanmoqda. Xizmat ko'rsatish protseduralari asosiy markazlashtiruvchi novda uni qo'zg'aysan mexanizmiga qayta ulash uchun bir necha dyuymni qo'lda tortib olishni talab qildi. 21:01 da bu tayoq to'satdan juda uzoqqa tortib olindi va SL-1 ketishiga sabab bo'ldi tezkor tanqidiy bir zumda. To'rt millisekundada hosil bo'lgan issiqlik juda katta quvvat ekskursiyasi yadro ichidagi yoqilg'ining erishiga va portlash bilan bug'lanishiga olib keldi. Kengayayotgan yoqilg'i haddan tashqari bosim to'lqini hosil qilib, suvni yuqoriga ko'tarib, reaktor kemasining yuqori qismiga kvadrat dyuym (69000 kPa) uchun eng yuqori bosimni urib yubordi. Tuproqli suv sekundiga 159 fut (48 m / s) tezlikda harakatlanib, o'rtacha bosimi kvadrat dyuymga 500 funt (3400 kPa) ga teng.[15] Ushbu ekstremal shakl suv bolg'asi butun reaktor kemasini yuqoriga qarab sekundiga 27 fut (8,2 m / s) ga surdi, qalqon tiqinlari esa sekundiga 85 futdan (26 m / s) chiqarildi.[15] Reaktor idishining yuqori qismida 6 teshik bo'lgan, yuqori bosimli suv va bug 'butun xonani buzilgan yadrodan radioaktiv chiqindilar bilan purkagan. Keyinchalik olib borilgan tergov natijalariga ko'ra, 26000 funt (12000 kg) (yoki 13 qisqa tonna) kema 9 fut 1 dyuym (2.77 m) ga sakrab tushgan, uning qismlari reaktor binosining shiftiga urilib, asl joyiga qaytmasdan oldin,[11][20][15] va ish joyiga izolyatsiya va shag'al yotqizish.[15] Agar kemaning # 5 muhr korpusi yuqori kranga urilgan bo'lsa, bosim kemasi taxminan 3 metrga ko'tarilish uchun yuqoriga ko'tarilgan momentumga ega edi.[15] Ekskursiya, bug 'portlashi va kemalarning harakatlanishi uchun butun vaqt ikki va to'rt soniya orasida davom etdi.[15]

Suv va bug 'purkagichining oqibatida ikkita operator polga qulab tushdi, natijada biri halok bo'ldi, boshqasi og'ir jarohat oldi. Reaktor kemasining yuqori qismidagi 7-sonli qalqon vilkasi uchinchi kishini tos suyagi orqali mixlab qo'ydi va yelkasidan chiqib, shiftga mahkamlab qo'ydi.[11] Qurbonlar armiya edi Mutaxassislar Jon A. Byorns (22 yosh) va Richard Leroy Makkinli (27 yosh) va Dengiz kuchlari Dengiz Qurilish bo'yicha elektr bo'yicha mutaxassis Birinchi sinf (CE1) Richard C. Legg (26 yosh).[21][22][23] Keyinchalik muallif Todd Taker tomonidan Byorns (reaktor operatori) tayoqchani ko'tarib ekskursiyaga sabab bo'lganligi aniqlandi; Legg (smena boshlig'i) reaktor kemasining tepasida turgan va ustunga mixlangan va shiftga mahkamlangan; va Makkinli (stajyor) yaqin joyda turdi. Qutqaruvchilar faqat Makkinlini tirik holda, hushsiz va chuqur shok holatida topdilar.[11] Bu SL-1 Tergov kengashining tahliliga mos keldi[24] va Byrnes va Legg bir zumda vafot etgan degan xulosaga kelgan otopsi natijalariga mos keladigan bo'lsa, McKinleyda uning bosh terisida diffuz qon ketish alomatlari borligi, bu uning yaralariga bo'ysunishdan taxminan ikki soat oldin omon qolganligini ko'rsatmoqda.[25] Uchala erkak ham jismoniy shikastlanishdan jarohat olishdi;[11][25] ammo, yadroviy ekskursiya natijasida paydo bo'ladigan radiatsiya odamlarga tirik qolish imkoniyatini bermagan bo'lar edi, hatto agar ular portlash natijasida o'lmagan bo'lsa ham tanqidiy voqea sodir bo'lgan.

Reaktor printsiplari va hodisalari

Bir nechta "kinetik" omillar yadro reaktorida ishlab chiqarilgan quvvat (issiqlik) ning boshqaruv tayoqchasi holatidagi o'zgarishlarga ta'sir qilish tezligiga ta'sir qiladi. Dizaynning boshqa xususiyatlari issiqlikning reaktor yoqilg'isidan sovutish suyuqligiga qanchalik tez uzatilishini boshqaradi.

The yadro zanjiri reaktsiyasi bor ijobiy fikr har doim tanqidiy massa yaratilganda komponent; xususan, har bir bo'linish uchun ortiqcha neytronlar ishlab chiqariladi. Yadro reaktori ichida bu ortiqcha neytronlar juda muhim massa mavjud bo'lguncha boshqarilishi kerak. Eng muhim va samarali boshqaruv mexanizmi ortiqcha neytronlarni yutish uchun boshqaruv tayoqchalarini ishlatishdir. Boshqa boshqaruv elementlariga reaktor hajmi va shakli va mavjudligi kiradi neytronli reflektorlar yadro ichida va atrofida. Yutish yoki neytronlarni aks ettirish miqdorini o'zgartirish neytron oqimiga ta'sir qiladi va shuning uchun reaktorning quvvatiga ta'sir qiladi.

Bitta kinetik omil - ko'pchilikning moyilligi engil suv bilan boshqariladigan reaktor (LWR) dizaynlari salbiy bo'lishi kerak moderator harorat va reaktivlikning bekor koeffitsientlari. (Bug'ning zichligi pastligi sababli, suv bug'ining cho'ntaklari LWRda "bo'shliqlar" deb nomlanadi.) Salbiy reaktivlik koeffitsienti shuni anglatadiki, suv moderatori qizib ketganda molekulalar bir-biridan uzoqlashadi (suv kengayadi va oxir-oqibat qaynaydi) va neytronlar yoqilg'ida bo'linishni keltirib chiqaradigan energiya uchun to'qnashuv bilan sekinlashishi ehtimoldan yiroq. Shu sababli salbiy teskari aloqa mexanizmlar, aksariyat LWRlar tabiiy ravishda reaktor yadrosida hosil bo'ladigan qo'shimcha issiqlikka javoban ularning parchalanish tezligini pasaytiradi. Agar suv yadro ichida qaynab ketadigan darajada issiqlik hosil qilinsa, bu atrofdagi chiqindilar keskin kamayadi.

Ammo, yadroviy reaktsiyadan quvvat chiqishi tez o'sganda, suvning isishi va qaynashi bo'shliqlar yadro reaktsiyalarining pasayishiga olib kelgandan ko'ra ko'proq vaqt talab qilishi mumkin. Bunday holatda, reaktor quvvati suvning kengayishi yoki qaynatilishidan salbiy teskari aloqa qilmasdan tez o'sishi mumkin, hatto u atigi 1 sm (0,39 dyuym) masofada joylashgan kanalda bo'lsa ham. Kuchli isitish yadro yoqilg'isida paydo bo'ladi, bu yadro ichidagi metallarning erishi va bug'lanishiga olib keladi. Tez kengayish, bosimning oshishi va yadro qismlarining ishdan chiqishi SL-1da bo'lgani kabi yadroviy reaktorning yo'q qilinishiga olib kelishi mumkin. Kengayish va issiqlik energiyasi yadro yoqilg'isidan suvga va idishga borgan sari, etarli moderator yo'qligidan yoki yoqilg'i tanqidiy massa. Avtohalokatdan keyingi SL-1 tahlilida olimlar ikkita o'chirish mexanizmining deyarli teng kelishini aniqladilar (pastga qarang).

Yana bir tegishli kinetik omil - bu nima deyiladi kechiktirilgan neytronlar yadrodagi zanjir reaktsiyasiga. Ko'pgina neytronlar ( tezkor neytronlar) deyarli bir zumda bo'linish orqali hosil bo'ladi. Ammo bir nechtasi - taxminan 0,7 foiz U-235 - barqaror holatida ishlaydigan yonilg'i bilan ishlaydigan reaktor - ma'lum bo'linish mahsulotlarining nisbatan sekin radioaktiv parchalanishi natijasida hosil bo'ladi. (Ushbu bo'linish mahsulotlari yonilg'i plitalari ichida uran-235 yoqilg'isiga yaqin joyda saqlanib qoladi.) Neytronlarning bir qismini ishlab chiqarishni kechiktirish - bu reaktor quvvatining o'zgarishini odamlar va mashinalar uchun qulay bo'lgan vaqt shkalasi bo'yicha boshqariladigan bo'lishiga imkon beradi.[26]

Chiqarilgan boshqaruv moslamasi yoki zahar bo'lsa, reaktor paydo bo'lishi mumkin tanqidiy faqat tezkor neytronlarda (ya'ni tezkor tanqidiy ). Reaktor tezkor vaziyatga tushganda, quvvatni ikki baravar oshirish vaqti 10 mikrosaniyadagi tartibda bo'ladi. Haroratning quvvat darajasiga rioya qilishi uchun zarur bo'lgan vaqt reaktor yadrosi dizayniga bog'liq. Odatda, sovutish suvi harorati an'anaviy LWRda quvvatdan 3-5 soniya orqada qoladi. SL-1 dizaynida bug 'hosil bo'lishidan oldin u taxminan 6 millisekund edi.[15]

SL-1, agar u butunlay olib tashlangan bo'lsa, juda katta ortiqcha reaktivlikni ishlab chiqarishga qodir bo'lgan asosiy markaziy boshqaruv tayoqchasi bilan qurilgan. Qo'shimcha tayoq qisman yadro yoqilg'isiga ega bo'lgan 59 ta yonilg'i agregatlaridan atigi 40 tasini yuklash to'g'risida qaror qabul qilganligi sababli paydo bo'ldi va shu bilan protetib reaktor yadrosi markazda faolroq bo'ldi. Oddiy ish rejimida boshqaruv tayoqchalari tortib olinadi, ular doimiy yadroviy reaktsiya va elektr energiyasini ishlab chiqarish uchun etarli reaktivlikni keltirib chiqaradi. Biroq, ushbu baxtsiz hodisada reaktivlik qo'shilishi reaktorni tezligini 4 millisekundda taxmin qilingan vaqt ichida qabul qilishi uchun etarli edi.[27] Yoqilg'i isishi alyuminiy qoplamadan o'tishi va yadroning barcha qismlarida quvvatni o'sishini manfiy moderator harorati va bekor qilingan teskari aloqa orqali to'liq to'xtatish uchun etarli miqdorda suvni qaynatish uchun juda tez edi.[15][27]

Baxtsiz hodisadan keyingi tahlil natijada yakuniy nazorat qilish usuli (ya'ni tezkor kritik holatning tarqalishi va doimiy yadroviy reaktsiyaning tugashi) yadroni halokatli demontaj qilish yo'li bilan sodir bo'ldi: halokatli eritish, bug'lanish va natijada qismlarning an'anaviy portlovchi kengayishi eng katta issiqlik tez ishlab chiqariladigan reaktor yadrosi. Hisob-kitoblarga ko'ra, bu yadro isitish va bug'lanish jarayoni taxminan 7,5 millisekundada sodir bo'lgan, bug'ning reaktsiyasini to'xtatish uchun etarli miqdordagi bug 'hosil bo'lishidan oldin, bug' yopilishini bir necha millisekundaga urgan. Asosiy statistik ma'lumotlarga ko'ra yadro nima uchun parchalangani aniq ko'rsatib turibdi: 3 MVt quvvatga ega bo'lgan reaktor bir zumda 20 GVt yuqori nuqtada ishladi, quvvat zichligi uning xavfsiz ishlash chegarasidan 6000 baravar yuqori.[13] Bu tanqidiy voqea sodir bo'lgan 4.4 x 10 hosil qilgan deb taxmin qilinadi18 yoriqlar,[13] yoki taxminan 133 megajoul (32 kilogramm trotil).[27]

Kuchli ekskursiyadan keyingi tadbirlar

Tekshirilmoqda radioaktiv ifloslanish yaqin atrofda 20-avtomagistral

Reaktor joylashgan joyda boshqa odamlar bo'lmagan. Yadro reaktsiyasining tugashiga faqat reaktor dizayni va isitiladigan suv va yadro elementlarining erishi, yadro elementlarini ajratish va moderatorni olib tashlashning asosiy fizikasi sabab bo'lgan.

Reaktorning ustidagi issiqlik sezgichlari soat 21: 01da markaziy sinov maydonchasi qo'riqxonasida signalni o'rnatdi. MST, voqea sodir bo'lgan vaqt. O'sha kuni ertalab va tushdan keyin soxta signallar paydo bo'ldi. Olti nafar o't o'chiruvchidan iborat birinchi javob brigadasi (Ken Dirden Asst boshlig'i, Mel Xess podpolkovnik, Bob Archer, Karl Jonson, Egon Lemprext, Jerald Styuart va Vern Konlon) to'qqiz daqiqadan so'ng yana bir yolg'on signalni kutishdi.[28] Dastlab ular hech qanday g'ayrioddiy narsani sezmadilar, binodan faqat bir oz bug 'ko'tarildi, sovuq 6 ° F (-14 ° C) kecha uchun normal edi. Boshqarish binosi odatdagidek ko'rinardi. Yong'in o'chiruvchilar reaktor binosiga kirib, radiatsion ogohlantiruvchi chiroqni payqashdi. Zinapoyadan SL-1 qavat darajasiga ko'tarilayotganda ularning nurlanish detektorlari maksimal chegaradan keskin sakrab tushishdi. Chetga chiqishdan oldin ular reaktor xonasiga qarashdi.[28]

21: 17da, a sog'liqni saqlash fizigi keldi. U va o't o'chiruvchi, ikkalasi ham havo tanklari va har qanday potentsial ifloslantiruvchi moddalarni chiqarib tashlash uchun niqobda ijobiy bosim bo'lgan niqoblarni kiyib, reaktor binosi zinapoyalariga yaqinlashdilar. Ularning detektorlari 25 ni o'qiydilar röntgenlar soatiga (R / soat) ular zinadan ko'tarilayotganda va orqaga chekinishdi.[29]

Bir necha daqiqadan so'ng sog'liqni saqlash fizikasi javob guruhi o'lchash qobiliyatiga ega radiatsiya o'lchagichlari bilan kelishdi gamma nurlanishi soatiga 500 R gacha va to'liq tanadagi himoya kiyimlari. Bitta sog'liqni saqlash fizigi va ikkita o't o'chiruvchi zinapoyadan yuqoriga ko'tarilib, tepadan, reaktor xonasida zarar ko'rdi. Maksimal o'lchov ko'rsatkichlarini ko'rsatadigan hisoblagich bilan ular reaktorga yaqinroq borishdan va orqaga qaytish xavfidan ko'ra orqaga chekindilar.

Zambil uskunasi. Maxsus kimyoviy radiologik bo'linmaning armiya ko'ngillilari Dugway isbotlanadigan zamin kran qurilmani SL-1 reaktor binosiga to'g'ridan-to'g'ri reaktor idishi ustidagi shiftga mahkamlangan odamning tanasini (Legg) yig'ish uchun kiritishdan oldin mashq qilingan.

22:30 atrofida. MST, saytni boshqarayotgan pudratchining SL-1 operatsiyalari bo'yicha rahbari (Yonish muhandisligi ) va sog'liqni saqlash fizikasi rahbari keldi. Ular soat 22:45 atrofida reaktor binosiga kirib, suvga botgan ikki tanasi buzilgan odamni topdilar: biri aniq o'lik (Byorns), ikkinchisi salgina harakatlanib (Makkinli) va nola qilmoqda. Bir kishiga bitta kirish va 1 daqiqalik cheklov bilan zambilga ega 5 kishidan iborat guruh hanuzgacha 10:50 atrofida nafas olayotgan operatorni tikladilar; u hushiga kelmadi va soat 23:00 atrofida boshidan jarohat olib vafot etdi. Hatto echintirilgan tanasi shu qadar ifloslanganki, u taxminan 500 R / soat chiqardi. Ayni paytda, taxminan 23:38 da shiftga mixlangan uchinchi odam topildi. Barcha potentsial omon qolganlar tiklangan holda, qutqaruvchilarning xavfsizligi birinchi o'ringa chiqdi va ularni himoya qilish ishlari sustlashdi.

Birinchi jabrlanuvchini qutqarish paytida uch kishi uni tashqi zinapoyadan olib chiqishga urinishdi, lekin uni operatsiya joyidan o'tib chiqqandan so'ng, favqulodda chiqish eshigini to'sib turadigan uskunani topdilar, bu ularni orqaga burilib, asosiy zinapoyadan foydalanishga majbur qildi. Birinchi qurbonning harakatlanishi paytida, ikki kishi Scott Air Paks-ni muzlatib qo'ydi va ishlashni to'xtatdi. Bir kishi ishlamay qolganligi sababli evakuatsiya qilingan, boshqasi esa niqobini olib tashlagan va McKinley-ni evakuatsiya qilishni yakunlash uchun ifloslangan havo bilan nafas olgan.[30]

Uchinchi odam oxirgi marta topilgan, chunki u reaktor ustidagi shiftga qalqon vilkasi bilan mahkamlangan va uni osongina tanib bo'lmaydi.[11] 4 yanvarga o'tar kechasi oltita ko'ngillilar jamoasi Byornsning jasadini tiklash uchun ikki kishilik guruhlar ishtirokidagi rejadan foydalanganlar. 9-yanvar kuni bir vaqtning o'zida ikkitadan o'tkaziladigan estafetada o'n kishidan iborat guruh har biriga 65 soniyadan oshmasligi kerak edi, uzun tirgaklarning uchida o'tkir ilgaklar yordamida Leggning tanasini qalqon vilkasidan ushlab tortib, uni Bino tashqarisidagi kranga biriktirilgan 5 x 20 fut (1,5 x 6,1 m) zambil.[11]

Radioaktiv oltin 198Au odamning oltin soatlar tokasidan va misidan 64Cu Keyinchalik, sigaret zajigalka ichidagi vintdan reaktor haqiqatan ham juda muhim bo'lganligini isbotladi. Kashf qilinishidan oldin neytron bilan faollashtirilgan elementlar erkaklar buyumlarida olimlar yadro ekskursiyasi sodir bo'lganligiga shubha qilishgan, bu reaktor tabiatan xavfsiz ekanligiga ishonishgan. Ushbu topilmalar kimyoviy portlash avariyaga sabab bo'lgan degan dastlabki taxminlarni rad etdi.[20]

Uchalasining ham jasadlari qo'rg'oshin bilan o'ralgan qutilarga beton bilan muhrlangan va beton qopqoqli metall kassalarga qo'yilgan. Ba'zi yuqori radioaktiv tana qismlari Aydaho cho'lida radioaktiv chiqindilar sifatida ko'milgan. Armiya mutaxassisi Richard Leroy Makkinli 31-bo'limda dafn etilgan Arlington milliy qabristoni.

Ba'zi manbalar va guvohlarning ma'lumotlari har bir qurbonning ismlari va lavozimlarini chalkashtirib yuboradi.[11] Yilda Aydaho sharsharasi: Amerikadagi birinchi yadroviy avariya haqida aytilmagan voqea,[31] muallif shuni ko'rsatadiki, dastlabki qutqaruv guruhlari Byornni avval tirik deb topgan odam, Leggning jasadi reaktor qalqoni yonida topilgan va avtohalokatdan keyin kechasi tiklangan deb hisoblashgan va McKinley-ni to'g'ridan-to'g'ri shipga tirgak tirgak bilan mixlangan deb hisoblashgan. reaktor ustida. Jabrlanuvchilarga etkazilgan og'ir portlashlar natijasida yuzaga kelgan ushbu noto'g'ri identifikatsiya, keyinchalik murdani tekshirish paytida tuzatildi, ammo bu biroz vaqtgacha chalkashliklarni keltirib chiqaradi.[31]

McKinley-ni olib yurgan va Karnegi Qahramoni Jamg'armasi Komissiyasining Karnegi Qahramoni mukofotlarini olgan ettita qutqaruvchi: Pol-Dakvort, SL-1 operatsiyalari rahbari; Sidney Koen, SL-1 test rahbari; Uilyam Raush, SL-1 operatsiyalar bo'yicha yordamchi yordamchisi; Ed Vallario, SL-1 sog'liqni saqlash fizigi; Uilyam Gammill, navbatchi AEC sayt tadqiqotlari boshlig'i; Lovell J. Kallister, sog'liqni saqlash fizigi va Delos E. Richards, sog'liqni saqlash fizikasi bo'yicha texnik.[32]

Sababi

Kerakli parvarishlash protseduralaridan biri markaziy dastani uzib qo'yilgan avtomatlashtirilgan boshqaruv mexanizmiga biriktirish uchun uni taxminan 10 dyuym (10 sm) qo'lda tortib olishni talab qildi. Avariyadan keyingi hisob-kitoblarga ko'ra, asosiy boshqaruv tayoqchasi taxminan 51 dyuymdan tortib olingan va reaktorning ketishiga sabab bo'lgan tezkor tanqidiy natijada bug 'portlashi sodir bo'ldi. Yoqilg'i, yonilg'i plitalarining qismlari va yonilg'i plitalarini o'rab turgan suv juda issiqda bug'lanib ketdi. Ushbu isitish jarayonining kengayishi sabab bo'ldi suv bolg'asi chunki suv reaktor kemasi boshiga qarab yuqoriga qarab tezlashib, havo va undan keyin suv boshiga soniyasiga 160 fut urganida reaktor kemasining boshiga kvadrat dyuymiga (69000 kPa) eng yuqori bosimni keltirib chiqaradi (50 m / s). .[27]

Suv bolg'asi nafaqat reaktor kemasining o'ta jismoniy shikastlanishiga va buzilishiga olib keldi, balki idishning qalqon uchlarini ham chiqarib yubordi, shulardan biri Leggga mixlandi. Bug 'portlashi va suv bolg'asining eng ajablantiradigan va kutilmagan dalillari, reaktor kemasi ustidagi shiftdagi havoga 9 fut 1 dyuym (2,77 m) ga sakrab tushganida, avvalgi joyiga qaytmasdan oldin paydo bo'lgan taassurotlar edi. Avariyadan keyin o'tkazilgan tahlil natijasida reaktor idishi quruq degan xulosaga keldi, chunki suv va bug 'ko'p qismi zudlik bilan chiqarib yuborilgan yoki reaktor ichidagi issiqlik tufayli bug'lanib ketgan. A boreskop reaktorni olib tashlashdan oldin buni tasdiqlash uchun ishlatilgan.

Aynan suv bolg'asi reaktorga jismoniy zarar etkazdi, tepada va yaqin joyda turgan xodimlarning tez o'limiga va atrof-muhitga radioaktiv izotoplarning tarqalishiga sabab bo'ldi. SL-1 dan olingan saboqlardan biri shundan iboratki, o'chirish reaktori xona haroratiga qadar soviganida va suvning yuqori qismi bilan reaktor idishi boshi o'rtasida havo bo'shlig'i bo'lganida suv zarbasi o'ta xavfli. Baxtsiz hodisani tahlil qilishda berilgan tavsiyalardan biri shundan iboratki, o'chirish reaktorlari suv bilan yuqoriga to'ldirilib, quvvat ekskursiyasi bunday kuchli suv bolg'asini keltirib chiqara olmaydi. Havo suvni sezilarli darajada sekinlashtiradigan darajada zich emas, suv esa (deyarli siqilib bo'lmaydigan) portlovchi kuchlarni taqsimlashga va eng yuqori bosimni cheklashga qodir. Qo'shimcha suv, shuningdek, to'g'ridan-to'g'ri kema ustida bo'lganlar uchun juda samarali radiatsion qalqondir. SL-1-da yozma protseduralar reaktorni yo'q qilgan texnik protseduradan oldin suv sathini quyish bo'yicha ko'rsatmani o'z ichiga olgan.

Asosni tortib olish uchun eng keng tarqalgan nazariyalar quyidagilardir: (1) operatorlardan biri tomonidan sabotaj yoki o'z joniga qasd qilish, (2) boshqa operatorlardan birining xotini bilan aloqada bo'lgan o'z joniga qasd qilish, (3) asosiy boshqaruv tayoqchasi yoki (4) qasddan tayoqchani "mashq qilish" ga urinish (uning qobig'i ichida yanada silliq yurishini ta'minlash uchun).[33][34]Ta'mirlash jurnallarida texnik xodimlar nima qilmoqchi bo'lganligi haqida ma'lumot berilmagan va shu sababli avariyaning haqiqiy sababi hech qachon ma'lum bo'lmaydi. Tekshiruv deyarli ikki yil davom etdi.

Tergovchilar quvvatni chiqarish darajasini aniqlash uchun texnik xizmat ko'rsatish vaqtida o'rnatilgan oqim simlarini tahlil qildilar. Shuningdek, ular markaziy boshqaruv pog'onasidagi chizishlarni tekshirdilar. Ushbu ma'lumotlardan foydalanib, ular markaziy tayoq 20 dyuym (50,8 sm) tortib olingan degan xulosaga kelishdi. Reaktor 16,7 dyuymda (42,4 sm) juda muhim bo'lar edi va tayoq so'nggi 3,3 dyuymni (8,4 sm) bosib o'tishi uchun taxminan 100 milodiy kerak bo'ldi.[15] Bu hisoblab chiqilgandan so'ng, bir yoki ikki erkak buni amalga oshirishi mumkin yoki mumkin emasligini aniqlash uchun bir xil og'irlikdagi soxta nazorat tayoqchasi bilan tajribalar o'tkazildi. Tajribalar 48 funt (22 kg) vaznini simulyatsiya qilishni o'z ichiga olgan[35] markaziy tayoq tiqilib qoldi va bir kishi uni o'zi ozod qildi va tergovchilar eng yaxshi tushuntirish deb hisoblagan stsenariyni takrorladi: Byorns boshqaruv tayoqchasini bo'shashtirib sindirib, tasodifan tortib oldi va uchala erkakni ham o'ldirdi.[11] Markaziy tayoq qo'l bilan tezda tortib olinishi haqidagi nazariyani sinab ko'rishda uch kishi vaqt sinovlarida qatnashdi va ularning sa'y-harakatlari sodir bo'lgan yadroviy ekskursiya energiyasi bilan taqqoslandi.[36]

Maket uchun zaxira SL-1 qo'mondon tayoqchasi aktuatori ishlatilgan bo'lib, unda bir nechta predmetlar uchun qo'lni tortib olish tezligi o'lchangan. Uskunalar SL-1 dagi harakatga keltiruvchi umumiy yukni 84 kg funt sterlingga etkazish uchun og'irlik bilan simulyatsiya qilingan boshqaruv tayoqchasidan tashqari bir xil. [...] Sinov sub'ektga tayoqchani iloji boricha tezroq ko'tarishni buyurish orqali o'tkazildi, elektr taymer esa tayoq harakatining boshlanishidan tortib olishning oldindan belgilangan masofasigacha o'tgan vaqtni o'lchadi. 30 dyuymgacha bo'lgan masofalar o'lchandi.

[...]

Yuqoridagi fikrlar shuni ko'rsatadiki, 5,3 millisekundagacha qisqa muddat ishlab chiqarish uchun tayoqni tortib olishning talab qilinadigan darajasi inson qobiliyati chegaralarida bo'lgan.[36]

— IDO-19300, 1961 yil 3-yanvarda SL-1 reaktorining avariyasi, vaqtinchalik hisobot, 1961 yil 15-may

SL-1da boshqaruv tayoqchalari vaqti-vaqti bilan boshqaruv tayoqchasi kanaliga tiqilib qoladi. Boshqaruv tayoqchalarini to'g'ri ishlashini ta'minlash uchun ularni baholash bo'yicha ko'plab protseduralar o'tkazildi. Vaqti-vaqti bilan mashq bajarish va normal ishlash uchun tayoqchalarni tortib olishdan tashqari, har bir tayoqchaning tayoqchalarini tushirish sinovlari va skram-sinovlari mavjud edi. 1959 yil fevraldan 1960 yil 18 noyabrgacha skram va tayoqchalarni tushirish sinovlari uchun tirgakning tiqilib qolishining 40 ta holati va taxminan 2,5% ishlamay qolish darajasi bo'lgan. 1960 yil 18-noyabrdan 1960-yil 23-dekabrgacha tiqilib qolgan tayoqlarning keskin ko'payishi kuzatildi, bu davrda 23 ta va ishlamay qolish darajasi 13,0% ni tashkil etdi. Ushbu sinov muvaffaqiyatsizliklaridan tashqari, 1959 yil fevraldan 1960 yil dekabrgacha qo'shimcha 21 ta tayoqcha hodisasi yuz berdi; Ulardan 4 tasi operatsiyaning so'nggi oyida muntazam ravishda tayoqni tortib olish paytida sodir bo'lgan. 9-sonli markaziy novda, boshqa har qanday tayoqchalarga qaraganda tez-tez ishlatilgan bo'lsa ham, eng yaxshi operatsion ko'rsatkichga ega edi.

Tayoqning yopishishi noto'g'ri joylashish, korroziya mahsulotining ko'payishi, rulmaning aşınması, debriyaj aşınması va qo'zg'aysan mexanizmining muhr aşınmasıyla bog'liq. Sinovlar paytida tirgakka sabab bo'lgan ko'plab nosozlik rejimlari (masalan, rulman va debriyajning aşınması kabi) faqat nazorat qilish çubuğunun qo'zg'alish mexanizmi tomonidan amalga oshiriladigan harakatga tegishli bo'ladi. 9-sonli tayoq markazda joylashganligi sababli, uning hizalanishi yopishishga moyil bo'lgan 1, 3, 5 va 7-sonlardan yaxshiroq bo'lishi mumkin. Voqea sodir bo'lganidan so'ng, jurnallar va sobiq zavod operatorlari bilan Byorns amalga oshirayotgan qayta yig'ish jarayonida bironta tayoq bor-yo'qligini aniqlash uchun maslahatlashildi. Bir kishi buni 300 marta, boshqasi 250 marta amalga oshirgan; Ushbu protsedura davomida qo'lda ko'tarilganda ham hech qachon tayoq tayog'ini sezmagan edingiz. Bundan tashqari, hech kim hech qachon qo'l bilan qayta ulash paytida tiqilib qolgan tayoq haqida xabar bermagan.

1961 yil iyun oyida bo'lib o'tgan Kongress tinglovlari paytida SL-1 loyihasi menejeri JB Allred SL-1 zavodining yonish muhandisligi tomonidan "kecha-kunduz" ishlashini nazorat qilmaganligi, Atom energiyasi bo'yicha komissiya rad etganligi bilan bog'liqligini tan oldi. g'oya "byudjet sabablari bilan".[18] Allred 1960 yil 16-noyabr va 23-dekabrdagi so'nggi o'chirish oralig'ida tayoqning ko'payishi masalasida ham panjara qildi. O'sish to'g'risida Allred: "Men sezilarli darajada o'sish haqida to'liq xabardor emas edim" va "Men bu keskinlik haqida bilmas edim o'sish sodir bo'ldi. "[18]

Unga yopishib qolgan muammo haqida xabar berish uchun mas'ul shaxs kimligini so'raganda, Allred SL-1 operatsiyalari rahbari Pol Dakkuort bu haqda unga xabar berishi kerak edi, ammo aytmaganligini aytdi. Bosilganida, Allred agar boshqaruv tayoqchasi yopishib qolganligini bilganida, "batafsilroq tekshirish uchun zavodni yopgan bo'lar edi", deb aytdi.[18]

Mexanik va ashyoviy dalillar, yadro va kimyoviy dalillar bilan birgalikda ularni markaziy boshqaruv tayoqchasi juda tez tortib olingan deb ishonishga majbur qildi. ... Olimlar [SL-1 ning sobiq operatorlari] ga savol berishdi: "Agar siz markaziy boshqaruv tayoqchasini olib tashlasangiz, reaktor juda muhim bo'lishini bilasizmi?" Javob: "Albatta! Biz tez-tez radiolokatsiya stantsiyasida bo'lganimizda va ruslar kelganda nima qilishimiz haqida suhbatlashdik. Biz buni rad etgan edik."

— Susan M. Stacy, Printsipni isbotlash, 2000 yil[20]

Oqibatlari

The accident caused this design to be abandoned and future reactors to be designed so that a single control rod removal would not have the ability to produce the very large excess reactivity that was possible with this design. Today this is known as the "one stuck rod" criterion and requires complete shutdown capability even with the most reactive rod stuck in the fully withdrawn position. The reduced excess reactivity limits the possible size and speed of the power surge. The "one stuck rod" criterion did not originate as a result of the SL-1 accident. It was, in fact, a hard and fast design criterion long before the SL-1, from the beginning of the Dengiz reaktorlari program, under the leadership of Admiral Hyman Rickover. This design criterion started with the USSNautilus, and continued throughout subsequent submarine and surface ship designs, and with the Shippingport civilian nuclear plant. It continues to be a requirement for all U.S. reactor designs to this day.[qarama-qarshi ]

Although portions of the center of the reactor core had been vaporized briefly, very little korium tiklandi. The fuel plates showed signs of catastrophic destruction leaving voids, but "no appreciable amount of glazed molten material was recovered or observed." Additionally, "There is no evidence of molten material having flowed out between the plates." It is believed that rapid cooling of the core was responsible for the small amount of molten material. There was insufficient heat generated for any corium to reach or penetrate the bottom of the reactor vessel. The reactor vessel was removed on November 29, 1961, without accident. The only holes in the bottom of the vessel were the ones drilled to allow the insertion of boreskoplar to determine the condition of the melted core.

Even without an engineered qamoqxona binosi like those used today, the SL-1 reactor building contained most of the radioactivity, though yod-131 levels on plant buildings during several days of monitoring reached fifty times background levels downwind. Radiation surveys of the Support Facilities Building, for example, indicated high contamination in halls, but light contamination in offices.

Radiation exposure limits prior to the accident were 100 röntgens to save a life and 25 to save valuable property. During the response to the accident, 22 people received doses of 3 to 27 Röntgens full-body exposure.[37] Removal of radioactive waste and disposal of the three bodies eventually exposed 790 people to harmful levels of radiation.[38] In March 1962, the Atom energiyasi bo'yicha komissiya awarded certificates of heroism to 32 participants in the response.

The documentation and procedures required for operating nuclear reactors expanded substantially, becoming far more formal as procedures that had previously taken two pages expanded to hundreds. Radiation meters were changed to allow higher ranges for emergency response activities.

After a pause for evaluation of procedures, the Army continued its use of reactors, operating the Mobile Low-Power Reactor (ML-1 ), which started full power operation on February 28, 1963, becoming the smallest nuclear power plant on record to do so. This design was eventually abandoned after korroziya muammolar. While the tests had shown that nuclear power was likely to have lower total costs, the financial pressures of the Vetnam urushi caused the Army to favor lower initial costs and it stopped the development of its reactor program in 1965, although the existing reactors continued operating (MH-1A until 1977).

Tozalamoq

General Electric Corporation was tasked with the removal of the reactor vessel and the dismantling and cleanup of the contaminated buildings at the SL-1 project site.[15] The site was cleaned in 1961 to 1962, removing the bulk of the contaminated debris and burying it.[15] The massive cleanup operation included the transport of the reactor vessel to a nearby "hot shop" for extensive analysis.[15] Other items of less importance were either disposed of or transported to decontamination sites for various kinds of cleaning. About 475 people took part in the SL-1 site cleanup, including volunteers from the U.S. Army and the Atomic Energy Commission.[15]

The recovery operation included clearing the operating room floor of radioactive debris. The extremely high radiation areas surrounding the reactor vessel and the fan room directly above it contributed to the difficulty of recovering the reactor vessel. Remotely operated equipment, cranes, boom trucks, and safety precautions had to be developed and tested by the recovery team. Radiation surveys and photographic analysis was used to determine what items needed to be removed from the building first.[15] Powerful vacuum cleaners, operated manually by teams of men, collected vast quantities of debris.[15] The manual overhead crane above the operating floor was used to move numerous heavy objects weighing up to 19,600 pounds (8,900 kg) for them to be dumped out onto the ground outside.[15] Hot spots up to 400 R/hr were discovered and removed from the work area.

With the operating room floor relatively clean and radiation fields manageable, the manual overhead crane was employed to do a trial lift of the reactor vessel.[15] The crane was fitted with a dial-type load indicator and the vessel was lifted a few inches. The successful test found that the estimated 23,000 pounds (10,000 kg) vessel plus an unknown amount of debris weighed about 26,000 pounds (12,000 kg). After removing a large amount of the building structure above the reactor vessel, a 60-ton Manitowoc Model 3900 crane lifted the vessel out of the building into an awaiting transport cask attached to a tractor-trailer combination with a low-boy 60-ton capacity trailer.[15] After raising or removing 45 power lines, phone lines, and guy wires from the proposed roadway, the tractor-trailer, accompanied by numerous observers and supervisors, proceeded at about 10 mph (16 km/h) to the ANP Hot Shop (originally associated with the Yadro harakatlantiruvchi samolyot program), located in a remote area of the NRTS known as Sinov maydoni Shimoliy, about 35 miles (56 km) away.[15]

A burial ground was constructed approximately 1,600 feet (500 m) northeast of the original site of the reactor. It was opened on May 21, 1961.[14] Burial of the waste helped minimize radiation exposure to the public and site workers that would have resulted from transport of contaminated debris from SL-1 to the Radioactive-Waste Management Complex over 16 miles (26 km) of public highway. The original cleanup of the site took about 18 months. The entire reactor building, contaminated materials from nearby buildings, and soil and gravel contaminated during cleanup operations were disposed of in the burial ground. The majority of buried materials consist of soils and gravel.[39][40]

SL-1 burial site in 2003, capped with rap rap

Recovered portions of the reactor core, including the fuel and all other parts of the reactor that were important to the accident investigation, were taken to the ANP Hot Shop for study. After the accident investigation was complete, the reactor fuel was sent to the Idaho Chemical Processing Plant qayta ishlash uchun. The reactor core minus the fuel, along with the other components sent to the Hot Shop for study, was eventually disposed of at the Radioactive Waste Management Complex.[39]

The remains of the SL-1 reactor are now buried near the original site at 43°31′17.8″N 112°49′04.8″W / 43.521611°N 112.818000°W / 43.521611; -112.818000.[41] The SL-1 burial ground consists of three excavations, in which a total volume of 99,000 cubic feet (2800 m3) of contaminated material was deposited. The excavations were dug as close to basalt as the equipment used would allow and ranges from 8 to 14 feet (2.4 to 4.3 m) in depth. At least 2 feet (0.6 m) of clean backfill was placed over each excavation. Shallow mounds of soil over the excavations were added at the completion of cleanup activities in September 1962. The site and burial mound are collectively known as Qo'shma Shtatlar atrof-muhitni muhofaza qilish agentligi Superfund Operable Unit 5-05.[39][42]

Numerous radiation surveys and cleanup of the surface of the burial ground and surrounding area have been performed in the years since the SL-1 accident. Aerial surveys were performed by EG&G Las Vegas in 1974, 1982, 1990, and 1993. The Radiological and Environmental Sciences Laboratory conducted gamma radiation surveys every 3 to 4 years between 1973 and 1987 and every year between 1987 and 1994. Particle-picking at the site was performed in 1985 and 1993. Results from the surveys indicated that seziy-137 and its progeny (decay products) are the primary surface-soil contaminants. During a survey of surface soil in June 1994, "hot spots," areas of higher radioactivity, were found within the burial ground with activities ranging from 0.1 to 50 milliroentgen (mR)/hour. On November 17, 1994, the highest radiation reading measured at 2.5 feet (0.75 m) above the surface at the SL-1 burial ground was 0.5 mR/hour; local background radiation was 0.2 mR/hour. A 1995 assessment by the EPA recommended that a cap be placed over the burial mounds. The primary remedy for SL-1 was to be containment by capping with an engineered barrier constructed primarily of native materials.[39] This remedial action was completed in 2000 and first reviewed by the EPA in 2003.[42]

Movies and books

Animation of the film produced by the Atom energiyasi bo'yicha komissiya, mavjud Internet arxivi.

The U.S. Government produced a film about the accident for internal use in the 1960s. The video was subsequently released and can be viewed at Internet arxivi[43] va YouTube. SL-1 is the title of a 1983 movie, written and directed by Diane Orr and C. Larry Roberts, about the nuclear reactor explosion.[38] Interviews with scientists, archival film, and contemporary footage, as well as slow-motion sequences, are used in the film.[44][45] The events of the accident are also the subject of one book: Idaho Falls: The untold story of America's first nuclear accident (2003)[31] and 2 chapters in Proving the Principle - A History of The Idaho National Engineering and Environmental Laboratory, 1949–1999 (2000).[46]

In 1975, the anti-nuclear book Biz Detroytni deyarli yo'qotdik, tomonidan Jon G. Fuller was published, referring at one point to the Idaho Falls accident. Prompt Critical is the title of a 2012 short film, viewable on YouTube, written and directed by James Lawrence Sicard, dramatizing the events surrounding the SL-1 accident.[47] A documentary about the accident was shown on the Tarix kanali.[48]

A safety poster designed for engineering offices depicting the eritilgan SL-1 reactor core.[49]

Another author, Todd Tucker, studied the accident and published a book detailing the historical aspects of nuclear reactor programs of the U.S. military branches. Tucker used the Axborot erkinligi to'g'risidagi qonun to obtain reports, including autopsies of the victims, writing in detail how each person died and how parts of their bodies were severed, analyzed, and buried as radioaktiv chiqindilar.[11] The autopsies were performed by the same pathologist known for his work following the Sesil Kelli avtohalokati. Tucker explains the reasoning behind the autopsies and the severing of victims' body parts, one of which gave off 1,500 R/hour on contact. Because the SL-1 accident killed all three of the military operators on site, Tucker calls it "the deadliest nuclear reactor incident in U.S. history."[50]

Shuningdek qarang

Adabiyotlar

  1. ^ "3 die in reactor blast". Spokane Daily Chronicle. (Vashington). Associated Press. 1961 yil 4-yanvar. 1.
  2. ^ Hale, Steve (January 4, 1961). "3 killed in severe blast at Idaho A-reactor site". Deseret yangiliklari. (Solt Leyk-Siti, Yuta). p. A1.
  3. ^ "Reactor blast kills three, pours out radiation". Lewiston Morning Tribune. (Aydaho). Associated Press. 1961 yil 5-yanvar. P. 1.
  4. ^ "3 technicians die in reactor blast". Matbuot kotibi-sharh. (Spokane, Vashington). Associated Press. 1961 yil 5-yanvar. P. 2018-04-02 121 2.
  5. ^ Stacy, Susan M. (2000). "Chapter 16: The Aftermath" (PDF). Proving the Principle: A History of The Idaho National Engineering and Environmental Laboratory, 1949-1999. AQSh Energetika vazirligi, Idaho Operations Office. 150-157 betlar. ISBN  0-16-059185-6.
  6. ^ The Nuclear Power Deception Table 7: Some Reactor Accidents
  7. ^ Horan, J. R., and J. B. Braun, 1993, Occupational Radiation Exposure History of Idaho Field Office Operations at the INEL, EGG-CS-11143, EG&G Idaho, Inc., October, Idaho Falls, Idaho.
  8. ^ "Idaho: Runaway Reactor". Vaqt. 1961 yil 13-yanvar. Olingan 30 iyul, 2010.
  9. ^ a b v d e f g h men j k l m n o p q r Design of the Argonne Low Power Reactor (ALPR), ANL-6076 Reactor Technology, Grant, Hamer, Hooker, Jorgensen, Kann, Lipinski, Milak, Rossin, Shaftman, Smaardyk, Treshow, May 1961, University of Chicago, Argonne National Laboratory.
  10. ^ Steve Wander (editor) (February 2007). "Supercritical" (PDF). System Failure Case Studies. NASA. 1 (4). Arxivlandi asl nusxasi (PDF) 2007-11-27 kunlari. Olingan 2007-10-05.CS1 maint: qo'shimcha matn: mualliflar ro'yxati (havola)
  11. ^ a b v d e f g h men j Taker, Todd (2009). Atomik Amerika: halokatli portlash va qo'rqinchli admiral yadro tarixi yo'nalishini qanday o'zgartirdi. Nyu-York: Bepul matbuot. ISBN  978-1-4165-4433-3. Xulosa: [1]
  12. ^ LA-3611 A Review of Criticality Accidents, William R. Stratton, Los Alamos ilmiy laboratoriyasi, 1967
  13. ^ a b v LA-13638 A Review of Criticality Accidents (2000 Revision), Thomas P. McLaughlin, et al., Los Alamos milliy laboratoriyasi, 2000.
  14. ^ a b v d e SEC-00219, Petition Evaluation Report, Idaho National Laboratory (INL), Revision 2, NIOSH/ORAU, Idaho National Laboratory, March 2017
  15. ^ a b v d e f g h men j k l m n o p q r s t IDO-19311 Final Report of SL-1 Recovery Operation, Idaho Test Station, General Electric Corporation, July 27, 1962.
  16. ^ a b IDO-19012, CEND-82, SL-1 Annual Operating Report, Feb. 1959 - Feb 1960, Canfield, Vallario, Crudele, Young, Rausch, Combustion Engineering Nuclear Division, May 1, 1960.
  17. ^ a b Report on the SL-1 Incident, January 3, 1961, The General Manager's Board of Investigation, For Release in Newspapers dated Sunday, Curtis A. Nelson, Clifford Beck, Peter Morris, Donald Walker, Forrest Western, June 11, 1961.
  18. ^ a b v d e Radiation Safety and Regulation Hearings, Joint Committee on Atomic Energy, US Congress, June 12-15, 1961, including SL-1 Accident Atomic Energy Commission Investigation Board Report, Joint Committee on Atomic Energy Congress of the United States, First Session on Radiation Safety and Regulation, Washington, DC.
  19. ^ IDO-19024 SL-1 Annual Operating Report, February 1960 - January 3, 1961 Combustion Engineering Nuclear Division, CEND-1009, W. B. Allred, June 15, 1961.
  20. ^ a b v Stacy, Susan M. (2000). Proving the Principle - A History of The Idaho National Engineering and Environmental Laboratory, 1949-1999 (PDF). U.S. Department of Energy, Idaho Operations Office. ISBN  0-16-059185-6. Arxivlandi asl nusxasi (PDF) 2011-08-07 da. 15-bob.
  21. ^ "Nuclear Experts Probe Fatal Reactor Explosion". Times Daily. 1961 yil 5-yanvar. Olingan 30 iyul, 2010.
  22. ^ "Richard Legg" (JPEG). Qabrni toping. 2011 yil 14-may. Olingan 5 mart 2013.
  23. ^ Spokane Daily Chronicle - Jan 4, 1961. The article notes that Byrnes was a "Spec. 5" from Utica, Nyu-York, McKinley was a "Spec. 4" from Kenton, Ogayo shtati, Legg was a "Navy electrician L.C." dan Roskommon, Michigan.
  24. ^ Final Report of SL-1 Accident Investigation Board, SL-1 Board of Investigation, Curtis A. Nelson, Atomic Energy Commission, Joint Committee on Atomic Energy, September 5, 1962 (See Annual Report to Congress - U.S. Atomic Energy Commission, 1962, Appendix 8, pp. 518 to 523)
  25. ^ a b LAMS-2550 SL-1 Reactor Accident Autopsy Procedures and Results, Clarence Lushbaugh, et al., Los Alamos Scientific Laboratory, June 21, 1961.
  26. ^ Lamarsh, Jon R.; Baratta, Anthony J. (2001). Yadro muhandisligiga kirish. Yuqori Egar daryosi, Nyu-Jersi: Prentis-Xoll. p. 783. ISBN  0-201-82498-1.
  27. ^ a b v d IDO-19313: Additional Analysis of the SL-1 Excursion Arxivlandi 2011-09-27 da Orqaga qaytish mashinasi Final Report of Progress July through October 1962, November 21, 1962, Flight Propulsion Laboratory Department, General Electric Company, Idaho Falls, Idaho, U.S. Atomic Energy Commission, Division of Technical Information.
  28. ^ a b Berg, Sven (December 12, 2009). "Nuclear accident still mystery to rescue worker". Argus kuzatuvchisi. Olingan 6 aprel, 2015.
  29. ^ IDO-19302 IDO Report on the Nuclear Accident at the SL-1 Reactor January 3, 1961 at the National Reactor Testing Station, TID-4500 (16th Ed.), SL-1 Report Task Force, US Atomic Energy Commission, Idaho Operations Office, January 1962.
  30. ^ Carnegie Hero Fund Commission, Vallario award
  31. ^ a b v McKeown, William (2003). Idaho Falls: The Untold Story of America's First Nuclear Accident. Toronto: ECW Press. ISBN  978-1-55022-562-4., [2]
  32. ^ Carnegie Hero Fund Commission heroes:Duckworth award,Cohen award,Rausch award,Vallario award (with details of the event),Gammill award (some details),Callister award,Richards award.
  33. ^ ATOMIC CITY, by Justin Nobel Arxivlandi 2012-05-22 da Orqaga qaytish mashinasi Tin House Magazine, Issue #51, Spring, 2012.
  34. ^ A Nuclear Family, By Maud Newton The New York Times Magazine, April 1, 2012.
  35. ^ Grant, N. R.; Hamer, E. E.; Hooker, H. H.; Jorgensen, G. L.; Kann, W. J.; Lipinski, W. C.; Milak, G. C.; Rossin, A. D.; Shaftman, D. H. (1961-05-01). "Design of the Argonne Low Power Reactor (Alpr)": 75. doi:10.2172/4014868. OSTI  4014868. Iqtibos jurnali talab qiladi | jurnal = (Yordam bering)
  36. ^ a b "SL-1 Reactor Accident on January 3, 1961, Interim Report," May 15, 1961, IDO-19300, CEND-128, Combustion Engineering, Inc., Nuclear Division, Windsor, Connecticut.
  37. ^ Jonston, Vm. Robert. "SL-1 reactor excursion, 1961". Jonsonning arxivi. Olingan 30 iyul 2010.
  38. ^ a b Maslin, Janet (March 21, 1984). "Sl-1 (1983): Looking at Perils of Toxicity". The New York Times. Olingan 30 iyul, 2010.
  39. ^ a b v d EPA,OSWER,OSRTI, US. "Superfund - US EPA" (PDF). AQSh EPA.CS1 maint: bir nechta ism: mualliflar ro'yxati (havola)
  40. ^ Qarorni qayd etish, Stationary Low-Power Reactor-1 and Boiling Water Reactor Experiment-I Burial Grounds (Operable Units 5-05 and 6-01), and 10 No Action Sites (Operable Units 5-01, 5-03, 5-04, and 5-11), January 1996.
  41. ^ "2003 Annual Inspection Summary for the Stationary Low-Power Reactor-1 Burial Ground" (PDF). INEEL.
  42. ^ a b 2003 Annual Inspection Summary for the Stationary Low-Power Reactor Burial Ground, Operable Unit 5-05
  43. ^ "SL-1 The Accident: Phases I and II".
  44. ^ SL-1 kuni IMDb
  45. ^ "Film sharhlari".
  46. ^ Stacy, Susan M. (2000). Proving the Principle: A History of The Idaho National Engineering and Environmental Laboratory, 1949-1999. AQSh Energetika vazirligi, Idaho Operations Office. ISBN  0-16-059185-6.
  47. ^ Prompt Critical kuni YouTube by James Lawrence Sicard.
  48. ^ SL-1 Nuclear Accident kuni YouTube Tarix kanali
  49. ^ Mahaffey, James (2010). Atomic Awakening. Pegasus kitoblari. ISBN  978-1605982038.
  50. ^ Shulman, Review by Seth (19 April 2009). "Book Reviews: 'The Day We Lost the H-Bomb' - 'Atomic America'; by Barbara Moran - by Todd Tucker" - www.washingtonpost.com orqali.

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