ML19317F419
| ML19317F419 | |
| Person / Time | |
|---|---|
| Site: | Oconee, Peach Bottom  |
| Issue date: | 06/05/1973 |
| From: | US ATOMIC ENERGY COMMISSION (AEC) |
| To: | |
| Shared Package | |
| ML19317F412 | List: |
| References | |
| NUDOCS 8001140664 | |
| Download: ML19317F419 (5) | |
Text
. _.
si n
^
-(
~
1-
^
Y,,
OCONEE 2-3 SER SUPPLEMENT DOSE CALCULATIONS g
' Dose calculat' ions.for the'Oconce 2/3'SER Supplement were performed as the result of a revision in'the' site meteorological data (memo from H. R. Denton l
to-R.' C.lDeYoung,' dated 0ctober 19, 1972).
The revised meteorological Rdiffusion! factor-(X/Q) at the-site boundary was.about a factor of two greater than the dif fusion factor. used in the earlier dose calculations.
The accident cases investigated were the design basis loss-of-coolant accident, the fuel h'andling accident, and the hydrogen purge.
The LOCA dose calculations -include credit for iodine removal.by boric acid i
sprays, a refinement to the calculational technique which was not included in the original oconee dose calculations. The sprays were assumed to
. affect the removal of the elemental and particulate fractions of the iodine in the containment.
The spray removal rate for elemental iodine was calculated to be'1.1 hr~
for the injection period and 0.7 hr-for the recirculation period. The effbetiveness of the boric acid sprays for elemental iodine removal was assumed to terminate once the initial elemental iodine activity;had - been reduced-by a factor-of two.
For the particulate iodine,1 the. cffectiveness of the s' prays was assumed to terminate when the
. particulate activity had been reduced by a factor of 100.
The containment
-spray system patameters employed to calculate the elemental spray removal rates are shown in Table'l.
Fif ty : percent of the leakage.following a LOCA was assumed to go through the
~
penetration room l ventilation system filters which were considered to be 90% efficient for'the removal of elemental and particulate iodine and 70%
efficient for'the removal of organic iodine. The assumption that 50% of the leakage-was treated by the penetration room filters was consistent with
-the previous calculations and was addressed in the Ocnnee 1-Technical Specifications.-
.4 8001140hy
4
. for penetration room filtration and spray removal, the LOCA unith credit 2-hour. site exclusion boundary dose was calculated to be 235 rem to the thyroid and 5.5 rem-to the whole body.*
At the low population zone dis-
.tance the.30 day dose was calculated to be 108 rem to the thyroid and 1.5 rem to the whole body.
The 0-2 hour iodine dose reduction factor attributed to.the filters alone was 1.8 and to the sprays alone was 1.6 for a total
~ dose reduction factor of 2.9 for the filters and sprays.
The assumptions included in the LOCA dose calculation are shown in Table 2.
The fuel handling accident analysis assumed that all 208 rods in a fual bundle were damaged and that the accident occurred 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after shutdown of the reactor. The USAECAAR computer program which incorporates the source: terms and release assumptions of Regulatory Guide 1.25 was utilized to perform the dose calculations. The 2-hour dose at the site exclusion boundary was calculated to be 56 rem to the thyroid (1.0 rem to the whole body) without filters in the src..t fuel building ventilation system and 9.4 rem with filters.
We recommend the inclusion of filters even though
' the doses without the filters would be within 10 CFR Part 100 Guidelines.
The hydrogen purge dose levels at the site exclusion boundary were reported previously in a memo to R. C. DeYoung from H. R. Denton, dated September 14, 19725
^
The doses at the site boundary were 150 rem to the thyroid and 0.80 rem to the whole body. At the LPZ distance the doses were determined to be
'9.5 rem to the thyroid and 0.05 rem to the whole body.
The data input to the hydrogen purge dose model are shown in Table 3.
The purge dose plus the LOCA dose at the LPZ, 118 rem to the thyroid and 1.6 rem to the whole body, are' less than 10 CFR Part 100 doses and are acceptabic.
, *The USAECAAR and TACT computer' programs were used to calculate the doses.
t-
-=
= _
TABLE 1 BORIC ACID SPRAY PARAMETERS FOR 19240 VAL OF ELEMENTAL IODINE Injection Period 0 - 30 Min.
Recirculation Period (unt13 ef f ectiveness of spray terminates) 30 - 46 Min.
pH 4.5 Pump Flow Rate - Injection 1500 gpm Pump Flow Rate - Recirculation 1000 gpm Spray licight 82.5 ft.
6 Containment Volume 1.91 x 10 ft Mean Drop Size 3800 Microns Spray Renoval Rate (A )
g Injection Period 1.1 hr~
Recirculation Period 0.7 hr~
(,
i
TABLE 2 ElcjggSE_ASSU:UJIO q 2568 init Power Level Source Release Fractions, Reg. Guide 1.4 Breathing Rates Containment Leak Rate 0 - 1 Day 0.25% Day ~
~1 0.125% Day 1 - 30 Day
!!cteorological Dilution Factors 0-2 11ours Site Aoundary (1609m) 2.2 x 10
- sec/ra
~
-5 0-8 liours LPZ (9650s) 2.35 x 10
-6 4.7 x 10 8 - 24 11ours
-6 1.5 x 10 24 - 96 11ours
~7 96 - 72011ours 3.3 x 10 I
y
4 i
TABLE 3 DATA 11PUT FOR HYDROGEN PURGE DOSE MODEL 2568 Mit Power Level 0
3 1.9 x 10 ft Building Volume Continuous Type of Purge 460 Hours (19.2 Days) llold-up Time j
Duration of Purge 30 Days 10 Filter Reduction
-6 5.2 x 10 X/Q at Site Boundary
~7 3.3 x 10 X/Q at LPZ e
-