ML022680543
| ML022680543 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry, Watts Bar, Sequoyah  |
| Issue date: | 09/19/2002 |
| From: | Burzynski M Tennessee Valley Authority |
| To: | NRC/ADM/DAS/RDB |
| References | |
| 67FR31385 00007 | |
| Download: ML022680543 (6) | |
Text
"T 2_3 P; 1 2: 53 I.L.JRul!cs E, d D~ractiveas Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402-2801 Sp e rI 9 20 C i September 19, 2002
[*-t*
Rules and Directives Branch Office of Administration U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 31 3;/9/1)
Gentlemen:
NUCLEAR REGULATORY COMMISSION (NRC)
COMMENTS ON PROPOSED GENERIC COMMUNICATION -
CONTROL ROOM ENVELOPE HABITABILITY (CRH)
TAC NO.
MB2788 (VOL.
67 FEDERAL REGISTER 31385, DATED MAY 9, 2002)
TVA appreciates the opportunity to comment on the prpposed generic communication.
The original comment period expired on August 7, 2002; however, the NRC extended the expiration date 60 days after public regional meetings were held by NRC in July and August 2002.
TVA previously provided comments on a series of related draft regulatory guides in letters to NRC dated June 28, 2002 and March 15, 2002.
These included:
"* DG-1114, Control Room Habitability at Light-Water Nuclear Power Reactors
"* DG-1115, Demonstrating Control Room Envelope Integrity at Nuclear Power Reactors
"* DG-IIII, Atmospheric Relative Concentrations for Control Room Habitability Assessments at Nuclear Power Plants, and
"* DG-1113, Methods and Assumptions for Evaluating Radiological Consequences of Design Basis Accidents at Light-Water Nuclear Power Reactors TVA's comments the enclosure.
R. M. Brown at on the subject generic communication are provided in If you have any questions, please contact (423) 751-7228.
Sincerely, l k Burzynski Manager Nuclear Licensing Enclosure cc (Enclosure):
U.S. Nuclear Regulatory Commission ATTN:
Document Control Desk
/
b-Washington, D.C.
20555-0001
, u
ENCLOSURE COMMENTS ON PROPOSED GENERIC COMMUNICATION OMMENT 3
PROPOSED REVISION Revise the draft generic letter to address the bulleted comment items, and add an explanation for concluding that the single volume ASTM E741 test method is appropriate for the complex volume of a control room.
1 gunrp
.graph The draft generic letter states:
"Unlike the DP test, the E741 test measures the total CRE inleakage from all sources. It is well suited for assessing the integrity of positive or neutral-pressure CREs."
Several concerns exist with these statements. They are that ASTM E74 1:
Does not measure inleakage. Inleakage is inferred through a variety of indirect measurements and analyzes.
Determines total inleakage and does not define the method for inferring the spilt between filtered and unfiltered inleakage.
Does not provide guidance on defining the uncertainty associated with the inferred values of filtered and unfiltered inleakage.
Does not provide guidance to ensure that proper test configurations, mixing of tracer gas, or which form of the test should be performed in a given application.
Fails to define how uncertainties should be used in the assessments of control room habitability. For a pressurized control room the uncertainty can be significantly larger than the inferred mean inleakage.
COMMENT FED. REG.
FED. REG.
PARA. # OR COMMENT PROPOSED REVISION NUMBER PAGE COLUMN TITLE
. I
. Does not address application of the test results to meteorological conditions that differ from those occurring at the time of the actual testing.
Does not reflect that verbatim compliance is not possible and has not been achieved in control room tests to date.
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31386 1
Background, 10 The NRC states, "The CRE encompasses the control Revise the text of the draft generic letter to clarify paragraph room and... "
that the CRE encompasses the control room and other rooms and areas within the confines of the The term "control room envelope" is not a term used control room boundary. The control room boundary in previous regulation and is inconsistently used in is the physical surfaces (e.g., ducts, dampers, floors, Draft Regulatory Guides DG-1 114 and DG-1 115.
ceilings, walls, doors) that separate the CRE from The CRE term has the potential to infer that other other plant areas.
areas of the plant are included under GDC 19 which were not previously discussed. GDC 19 refers explicitly to the control room, and the SUP expands this area definition but restricts it based on occupancy.
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31386 3
Background - last ASTM E741 testing alone should not be identified as Revise the first sentence of the paragraph to read as:
paragraph having helped to identify deficiencies. The DP surveillance tests have also helped to identify "Testing has helped to identify a spectrum of potential system deficiencies.
CREHS deficiencies that affect system design, construction, and quality; system boundary ASTM E741 testing does not identify the exact construction and integrity; and technical source of inleakage. In order to identify the actual specification surveillance requirements."
sources of inleakage, a component test might be required. Furthermore, many of the examples that affect CRE and CREHS performance could be areas of exfiltration for positive pressure CREs that would more likely be identified as a result of adverse DP surveillance results rather that E741 testing.
As written, the paragraph overstates E741 testing benefits. Revise the paragraph to delete reference to E741 testing.
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COMMENT FED. REG.
FED. REG.
PARA. # OR COMMENT PROPOSED REVISION NUMBER' PAGE COLUMN TITLE
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31386 2
Background
The text states that:
Revise the sentence to read:
"Plants with a positive-pressure CRE have generally "Most plants with a positive-pressure CRE have a implemented testing programs. These programs technical specification surveillance to verify those verify those ventilation systems serving the CRE can ventilation systems serving the CRE can maintain the maintain the CRE at a positive differential pressure CRE at a positive differential pressure relative to relative to adjacent areas."
adjacent spaces."
These are surveillances, not test or testing program, unless the NRC staff has authorized the licensee to use alternative approach. NRC approved alternatives include pressurization flow rates, DP across filtration banks, etc.
The text should be revised to describe what exists at plants for determining positive pressure.
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31386 3
Background, 3Yd The discussion of the DP surveillance is not Revise the text to accurately describe what the DP paragraph characterized accurately.
surveillance does and does not accomplish.
The paragraph implies the surveillance is deficient.
Delete the first three sentences of the paragraph and This characterization is incorrect. The surveillance change it to read:
correctly determines the ability of the pressurization system to pressurize the control room envelope. This "The DP surveillance only ensures that in-leakage ensures that inleakage is not possible across major does not exist across major portions of the control portions of the control room boundary. However, room boundary."
the assertion that the surveillance cannot measure directly inleakage is correct. But, it is not intended Change fourth sentence to read:
to measure inleakage directly.
"The DP surveillance cannot determine...
The second assertion that the surveillance cannot determine whether there are unrecognized sources of pressurization is correct.
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31387 2
Discussion, 1V The final sentence states:
Revise the first paragraph of the discussion section to paragraph read:
"It is, therefore, imperative to the health and safety of the public that operators are confident of their "The NRC is concerned that some licensees have not safety in the CRE at all times."
maintained adequate configuration control over their CREs and have not corrected identified design and This statement is presented as an opinion. Industry performance deficiencies. Configuration control 3
COMMENT FED. REG.
FED. REG.
PARA. # OR COMMENT PROPOSED REVISION NUMBER PAGE COLUMN TITLE is unaware of any research that demonstrates must be maintained to ensure that operators can instances where an operator's perception of his function in a habitable environment."
safety based on CRH would affect his confidence in his abilities to perform his duties.
Statements of opinion should not be included in regulatory documents.
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31387 3
Discussion, The draft GL states:
Rewrite the sentence to read:
2'd full paragraph "Addressees are encouraged, but not required, to "Coordinating the responses is more efficient with a work closely with industry groups on the uniform approach to demonstrating compliance with coordination of their responses. Coordinating the the design bases of their CREs."
responses is more efficient, and public confidence may ensue from a uniform approach to demonstrating compliance with the design bases of their CREs."
There is no basis for the statement that public confidence will ensue if the licensees coordinate their responses to this draft GL. Furthermore, the phrase addressing public confidence does not add substance to the draft generic letter.
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31388 1
Discussion Editorial Comment Revise "Required" to "Requested."
The last paragraph before the Requested Information section states:
"Licensees unable to confirm item 1 under the Required Information section may also use DG-I 114 to develop and implement corrective actions."
The text should be revised to indicate that it is the "Requested Information."
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31388 1
Required This paragraph states:
Clarify the intent of this paragraph so that proper Information infiltration rates may be used with each type of Paragraph I (b)
"That the most limiting unfiltered inleakage into your assessment. Revise the paragraph to read:
CRE (and filtered inleakage if applicable) is 4
COMMENT FED. REG.
FED. REG.
PARA. # OR "
COMMENT PROPOSED REVISION NUMBER PAGE COLUMN TITLE incorporated into your fire and hazardous chemical
"(b) That the most limiting inleakage into your CRE assessment, and CRE integrity preserves reactor is incorporated into your hazardous chemical control capability or alternate shutdown panel in the assessments. This inleakage may differ from the event of a fire."
value assumed in your design basis radiological analyses. Also confirm that the reactor control This infers that the same limiting unfiltered inleakage capability is preserved from either the Control Room values should be used to assess all events. This may or the alternate shutdown panel in the event of a not be true since systems lineups may differ for a fire."
radiological, fire, and hazardous chemical events.
Furthermore, Draft Regulatory Guide DG-1 114, Regulatory Position 2.6, states:
"No regulatory limit exists on the amount of smoke allowed in the control room. Therefore, the plants ability to manage smoke infiltration is assessed qualitatively."
This Regulatory Position seems to imply that the fire assessment would not need to specify a specific inleakage value.
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31388 1
Required Paragraph L.(c) has extraneous text addressing Revise Paragraph l.(c) to read as:
Information ASTM E741 tracer gas testing as it relates to CRE Paragraph l(c) integrity. The request should focus solely on how
"(c) That if your facility has a technical specification and on what frequency CRE integrity is confirmed.
surveillance requirement for CRE integrity, it remains adequate. If your facility does not currently have a technical specification surveillance requirement for CRE integrity, explain how and on what frequency you confirm your CRE integrity."
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