ML20236C093
| ML20236C093 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 07/23/1987 |
| From: | Bailey J GEORGIA POWER CO., SOUTHERN COMPANY SERVICES, INC. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| GN-1387, NUDOCS 8707290335 | |
| Download: ML20236C093 (2) | |
Text
1 i
~ * ' '
' Georgia Power Company ;
'f l Post Office Box 282.
l
, Waynesboro, Georgia 30830
- Telephone 404 554-9961, 404 724 8114
_j Souther mpany ervic'es,Inc.
Birmingham, Alabama 35202 Telephone 205 870 6011 -
V tle Project 7
l July 23,1987 1
United. States Nuclear Regulatory Commission l
Document Control Desk File: X7BC35.
-i Washington, D. C.
20555 Log:
GN-1387 j
NRC DOCKET NUMBER 50-425 CONSTRUCTION PERMIT NUMBER CPPR-109 V0GTLE ELECTRIC GENERATING PLANT - UNIT 2 RADIOLOGICAL CONSEQUENCES OF ELECTRICAL' PENETRATION FILTER AND EXHAUST-SYSTEM DELETION
Reference:
Letter GN-1374, dated-June l',
1987 Letter GN-1384, dated July 15, 1987 Gentlemen:
In. the referenced letters we described a proposed revision to the design-bases of the Unit 2 _ Control Building HVAC' System, eliminating.
the electrical penetration filter and exhaust ' system.
'In response
'to questions from your staff: regarding this subject the following.
discussion is provided.
Concern:
Please provide a comparison of the post-LOCA radioactivity concentration outside the' control building to that inside' the control building:(levels A and B).
Response
A calculation was performed to compare. radioactivity concentration outside the control building to _ that inside the control building on levels A and B.
The results of this calculation indicate that the concentration inside
- 4 the control building levels A and B will' be approximately 15% higher than outside the control building at 30 days 1
post-LOCA.
Conservatively multiplying the FSAR Table-15.6.5-6 control room thyroid dose by 1.15 results in i
a dose which is within the guidelines established by General j
Design Criterion 19.
)
The' above comparisons and results are conservative for ~ the following j
reasons:
J i
1.
Electrical penetration leakage represents a small-contribution.
~j to the -total control building level A and B activity,. thus. the concentration slowly builds up to 1.15 times the = outside air-concentration.
Applying ' a constant factor of.1.15 to the entire.
(time dependent) calculated dose is conservative.
l.fo-i f
g' lh; jd/d k5 I
lo o
- _ - _ = - _
+ n Radiological Consequences of Electrical Penetration' Filter and Exhaust System Deletion:
File:
X7BC35 Log:
GN-1387
' July 23. 1987 Page two 2.
The' control room filtered HVAC intake source terms are comparable to tne unfiltered-inleakage source terms.
The filtered HVAC intake source terms are unaffected. by higher _ control building a
level A and B concentration thus ' applying a factor of 1.15 to the entire calculated dose is conservative.
3.
The control room is pressurized to minimize unfiltered inleakage.
l Accident analyses assume.10 cfm unfiltered inleakage. to account for air transfer through' doorways on' ingress or egrass from the-control room even though a "two-door vestibule" type entry into the. control room is provided as described in FSAR Section 6.4.
4.
Because the doors into the control room are located on' level 1 which,has no HVAC system interconnections to the levels A and B HVAC ' system, the higher level A and B. concentration would be slowly transferred, diluted, and mixed by the level 1 and 2 HVAC
-system. No credit for this additional' dilution has been taken.
If you have.-any further questions regarding this proposal; we would be pleased to meet.with you at your convenience.
Sincerely.
h-J. A. Bailey Project Licensing Manager JAB /wk1 xc: NRC Regional Administrator NRC Resident Inspector J. P. O'Reilly R. E. Conway L. T. Gucwa R. A. Thomas J. E. Joiner, Esquire B. W. Churchill, Esquire M. A. Miller (2)
G. Bockhold, Jr.
R. Goddard, Esquire D. Feig-R. W. McManus Vogtle. Project' File l
y L
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