ML20031G658
| ML20031G658 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 10/19/1981 |
| From: | Hukill H METROPOLITAN EDISON CO. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| L1L-220, NUDOCS 8110230431 | |
| Download: ML20031G658 (3) | |
Text
Metropolitan Edison Company J
Post Of fice Box 180 g
Middletown, Pennsylvania 17057 Writer's Direct Dial Number October 19, 1981 LlL 220 di i
g( V s
1 Office of Nuclear Reactor Regulation p
l W
At ti. :
J. F. Stolz, Chief j% nJ Division of Licensing l
OCT2 319816 $
Operating Reactors Branch No. 4 2;
y U. S. Nuclear Regulatory Commission w
y!
Washington,.D.C.
20555 j)i g
j
Dear Sir:
q, g,[f \\
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 Dochet No. 50-289 Clarification of TSCR No. 34B H /0 Monitoring System 2 2 Enclosed please find our response to your questions addressed in your letter of July 31, 1981 concerning the Waste Gas System at TMI-1.
This information confirms and supplements our staffs' telephone conversation of July 9,1981 on the subject system.
Additionally, the following information is provided for clarification of an item discussed in L1L 052 of March 27, 1981:
o Grab Sample / Analysis - Although the Hays Gas Analyzer provides the capability of sampling at 10 different points as listed on p ge 2 of TSCR 34B, routinely it is selected to sample less than 10 points in the Waste Gas System.
Additionally, a grab sample analysis of each point takes approximately 40 minutes.
In order to sample 10 points and analyze those 10 points it would require 420 minutes.
Finally, it is our understanding that the semi-annual reports will continue to be done under the previous Technical Specification requirements through i
I the quarter in which the Appendix I Technical Specifications (Amendment 72) are implemented. The annual environmental report will continue to be done under the previous Technical Specifications requirement through the year in which the Appendix I Technical Specifications are implemented.
l Sincerely, Eill Director, TMI-l HDH: CWS:vj f Enclosure i
cc:
R. Jacobs J.
Ropoli C. Willis 8110230431 811019 Metrot P PDR r i the General Pubhc U ltes System 51 {
PDR ADOCK 05000289
c 1
QUESTION:
1.
Are procedures in effect which require keeping waste gas concentrations below 3% M, and 2% 0 by volume at each 2
of the sampling points?
RESPONSE
Radwaste Panel D has an 0 high alarm setpoint of 0.1%
2 by volume and H, high alarm setpoint of 3% by volume ss detected by the' Hays Gas Analyzer. The Hays Gas Analyzer will sample only those points selected.
In the event of an H high alarm, Alarm Response Procedure Rad Waste Panel 2
D requires the following action be taken:
Check Gas Analyzer to determine which tank caused alarm.
If waste gas decay tank is alarming, isolate the tank in preparation for diluting with N and/or venting.
If any 9
other tank is alarming, purge if with N which forces the 2
H t the waste gas decay tank 2
In the event of an 0, high alarm Alarm Response Procedure on Rad Waste Panel D' requires the following action be taken:
Check gas analyzer to determine which tank has high 0 2
concentration.
Verify that N supply is adequate and 2
pressure regulator is working properly.
Purge N int 2
tank with high 0, concentration to reduce the 0 c neentration.
~
2 QUESTION:
2.
Is the waste gas sy? tem pressure contra 11ed automatically so it stays between 15.5 and 16.4 psia?
RESPONSE
The pressure in the low pressure vent header of the waste gas system is automatically maintained between 15.9 psia and 16.4 psia by a vaste gas compressor per the waste gas operating procedure.
If the pressure in the low pressure vent header increases to 16.5 psia or greater, the standby compressor will pick up.
The system is designed-such that WDG-V54 (low pressure vent header nitrogen admission valve) opens to supply nitrogen to the header when header pressure decreases below 15.3 psia. WDG-V54 shuts when i
l pressure increases above 15.5 psia. A Gaseous Waste Disposal System Functional Test, will be conducted prior i
to restart in order to verify that the system performs j
as designed.
Based on test results, the setpoints may be changed.
l QUESTION:
3.
Is N constantly on supply to:
2 a) Bleed tanks at NI-V-17 b) Header at NI-V-37 c) Waste gas delay tank d)
Compressors at NI-V-23 & V-24 e) Make-up tank at NI-V-22 i
L
- - ~ _-_
4
RESPONSE
a)
No. NI-V-17 is normally shut as are the individual nitrogen purge valves for each reactor coolant bleed tank (WDG-V57, WDG-V58, and WDG-V59). These valves must be operated manually to supply nitrogen to the component.
b) Yes - Regulated on an as needed basis by WDG-V54.
[
c) No -WDG-V66 is normally shut.
It must be operated manually to supply nitrogen to the waste gas delay tank.
d) Yes - Regulated on an as needed basis, e) No - NI-V-22 is normally shut.
It must be operated j
nanually to supply nitrogen to the make-up tank.
QUFSTION:
4.
Is the sketch (Figure 1) of the waste gas system essentially correct?
RESPONSE
The latest revisions of the vaste gas system drawings were confirmed during the telephone conversation.
For those drawings held by the NRC which were not the latest j
i revision, a. copy of the latest revision was provided to the NRC. The sketch in Figure 1 of your letter dated July 31, 1961 is essentially correct.
QUESTION:
5.
During normal operation, is the principle source of ~i 3 letdown to the RC bleed tanks? Is this bleed no gres!r?
than 4000 gal / day?
RESPONSE
The principle source of hydrogen in the vent header, during normal operation, can be attributed to reactor coolant system letdown to a reactor coolant bleed tank, except i
for periodic venting of the make-up tank to the vent header.
i Based on our review of cycle 4 operation, letdown to a bleed tank did not exceed 4000 gal / day.
l QUESTION:
6.
When grab samples are necessary, will they be taken from the points where concentrations are most likely to be l
high, such as from CE-108 during degas?
I
RESPONSE
A procedure will be written to establish sample locations I
when grab samples are necessary for various modes of operation.
I i
i
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