ML20009G272
| ML20009G272 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 07/18/1981 |
| From: | Dutton D GEORGIA POWER CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| GN-138, IEB-81-03, IEB-81-3, NUDOCS 8108040065 | |
| Download: ML20009G272 (3) | |
Text
T
~
,.8
~'
Post Ofnce Box 4545 s
Adanta, Georpa 3o302
\\p-I//
gt oject
" * "* *
- 522 "
p
.r.
S 3 1931
(,u.g)$8," O hi
- 0 j
July 18, 1981 f
.'s
,n United States Nuclear Regulatory Commission Refsre'n'c'e Office of Inspection and Enforcement RII:
JP0 Region II - Suite 3100 50-424 101 Marietta Street 50-425 Atlanta, Georgia 30303 File:
X7BC24 Attention: Mr. James P. O'Reilly Log:
GN-138 Gentlemen:
The following is submitted in response to your letter dated April 10, 1981, requesting information concerning IE Bulletin 81-03.
The information format provided herein is similar to the Bulletin question format.
1.
a) Corbicula sp. is present in the Savannah River at the Vogtle jobsite.
b) The design of the Vogtle Nuclear Plant (VNP) incorporates a chlorination system to control biological growth and a travelling screen is used to prevent foreign matter from entering the river water makeup system. There is no instrumentation specifically designed to indicate the presence of organisms.
The potential for Corbicula to enter the VNP river makeup water system piping is credible, as the only physical barrier to infestation is the travelling screen with a 1/4" mesh.
Because this is larger than the size of the Corbicula larva, it is possible for the larva to enter the river makeup water 1
stream at high flow, low water conditions. However, the t
river is only a backup cource or* makeup water. The safety-related cooling water systems normally receive makeup water from the plant's demineralized water system or makeup wells, which have no evidence of Corbicula. Therefore, it is highly unlikely that safety-related cooling system would be i
degraded due to Corbicula infestation.
2.
At the present stage of construction, no potentially affected systems have been completed to the point of filling. Thus, g//
there is currently no infestation at Plant Vogtle.
y
//
810804006S 810718
{DRADOCK 05000424 PDR
Mr. James P. O'Reilly July 18, 1981 page two The potentially affected systems are:
a) River Water Makeup System (RWMS) b) Turbine Plant Cooling System (TPCS) c) Nuclear Service Cooling Water System (NSCWS) d) Waste Water Effluent System (WWES)
The RWMS, TPCS, and NSCW systems are provided with chlori-nation capability. However, only the RWMS and TPCS are felt to have chlorination capabilities sufficient to suc-cessfully combat Corbicula.
3.
a) Environmental monitoring on May 13, 1981, revealed the pre::ence of Corbicula in quantity both upstream and down-stream of the jobsite.
b) The RWMS is the only direct interface with the affected water. The RWMS is to be continuously chlorinated at a level of 10 ppm, providing a residual-free chlorine level of 1 ppm.
The TPCS, which receives makeup water from the river, will be chlorinated on a periodic basis depending upon season.
This chlorination will vary from once or twice per day in the sumer to once a week during the winter, with continuous chlorination during the Corbicula spawnino seasons as required. Maximum free residual cnlorine will be limited to
.5 ppm at the condenser discharge.
The NSCW system primarily obtains its makeup water from the plant makeup wells. The only time the NSCWS interfaces with the river water makeup system is during " low-low" water conditions in the NSCW cooling tower basins, and then only by administrative control. Thus, there is only a remote possibility of the NSCW system becoming contaminated with Corbicula.
In addition, the NSCWS is chlorinated on a periodic basis (from one hour / day in the summer to one hour / week in the winter) to a level of.2 to.f, ppm maximum residual-free chlorine at the outlets of the heat exchangers.
Should river water makeup be provided for the NSCW, proce-dures will insure that there is no infestation of NSCW by Corbicula (e.g., continuous chlorination for a prolonged period of time).
The seismic Category 1 standpipe portion of the fire protec-tion system derives its watar from the NSCWS; however, these lines are normally isolated from the NSCW system and are
" dry" lines.
_____.___d
=.
=__ _- _
~
Mr. James P. O'Reilly
~
July 18, 1981 page three The WWES uses RWMS water to dilute liquid radwaste dis-charges when required to meet 10 CFR 20 radioactivity level requirements.
Due to this requirement, there is direct communication between the RWMS and t.he WWES at the blowdown sump, and contamination may occur in this case. There are no means provided for the control of Corbicula in this system.
This reply contains no proprietary information and may be placed in the NRC's Public Document Room, t
ours,l m.~
D ug Dut n Project G neral Manager RCW: sew l
1 Doug Dutton states that he is Project General Manager of Georgia Power Company's Vogtle Project and is authorized to execute this oath on behalf of Georgia Power Company and that to the best of his knowledge and belief the fac et forth in this letter are true.
\\
\\
GPC:
W Dkug'Dutton Sworn to and subscribed before me this J/ 4/ day of July, 1981.
Cb2 cM ktsry Public, Georgfa. State at tase My Commluion Expires March 21,1985
'xc: U. S. Nuclear Regulatory Commission Attn:
Victor J. Stello, Jr., Director Office of Inspection and Enforcement I
Washington, D.C.
20555 l
J. H. Miller, Jr.
D. E. Dutton R. J. Kelly K. M. Gillespie R. E. Conway E. D. Groover G. F. Head L. T. Gucwa R. H. Pinson B. L. Lex l
C. F. Whitmer C. R. Miles, Jr.
D. L. McCrar,v H. C. Nix R. A. Thomas R. W. Staffa J. A. Bailey J. L. Vota
- 0. Batum
-..