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..C, ATOMIC ENdRGY COMMISE*3N D
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Skovhol't. Assistant Director for Opurating Roactors, L V. )toore. Assistant Director f ar Boi].ing Water Reactors, L CHARCOAL OFF-CAS SYSTE!! ACCIDEi;T ASSESSIIEliTS FOR QUAD CITICS 14 2, A!!D DRCSDC;! 203 The Accident Analysis Branch has evaluated the conocquences of a postulated failure of tha Quad Cities Unles 152 off-gas sys tain and thn Drendon 243 off-nc.n s y s t ra n.
The assumptions used.for the.:uo sites aro identical except for power loval and meteorological dispersion-parameters.
Table 1 gives the assumptions and calculated doses.
The dispersion factor for Dresden is a Safety Guide 3 value since no onsite data could be found.
The analysis includon l
the nobio gas raloaan ratos specified in C.E.
topical report.
tiEDO 10734 based on a release rate of 100,000 microcuries por second after 30 minuta docay.
He have scaled this u p -- t o 350,000 uci/sec por unit at 30 minutes.
The analysis in-dicates chap failure of tho off-gas system'at Quad Cition and Dresden Units 203 uill produco doses in encess of the
. 5 rem guideline which we believe appropriata for this vintago plant to dofine Catogory 1 dosign.
(Itau plants would hava to moot.a 500 mr limit.)
tle recommand wither modifications to the system (such as ma kin:t the delay line or charcoal tanks seismic Category 1), or limiting oporation at high off-gas ratas.
The combined off-gan rato for th a.
units at Quad Cities would havn to be limitod to 175,000 uC1/sec at 30 ninutos.
The combinod oft-gan rato for Dcondon Units 2&3 should be limited to 650,000 uC1/noc at 30 minutos in order to keep tho potential done belou 5 rom.
'.Qv., cf.&g.% r.'.:.,. P i
,M lla ro l'd R. Donton, Asnistant Director for Sito Safaty Directorate o f Licensin ;
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D.
Silver J.
Kohlor R.
7.avadomki 3.
Griman A. Gintbugno J. !!. Ilondrio
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{ljt,1gv0 (121207 HIMilla-545 ppg
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-Q TABLE 1 SU.MMARY OF ACC'IDENT CALCULATIONS h*
't QUAD CITIES DRESDEL Power Level (nut) 2511 2527 Sumber of Units Using Common Delay Line 2
2
)
Condenser Lake Rata (SCFM) 18.5 18. '5.
Xenon Dela~y Ti=c (br) 377 377 Krypton Delay Ti=c (hr) 21, 21 Delay Time to Charcoal Sed 4
4 Noble Gas Release Rate Per Unit (uci/sec) (at 30 350,000 350,000 minutes delay)
,X~odine Release Rate (uCi/sec)
.5
.5 Accident Meteorology X/Q (sec/r.3) 3x10-3 6x10-A Whole Body Dose Contributions (for 2 units rem) a.
steam jet air ejector for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 8.7 1.7 b.
delay line for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 8.1 1.' G' c.
charcoal beds for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 5.8 d, A i
d.
total 22 4.5 Thyroid Dose (for 2 units)
.83
.'17 S
W e
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