ML100610057
| ML100610057 | |
| Person / Time | |
|---|---|
| Issue date: | 03/02/2010 |
| From: | Office of Nuclear Regulatory Research |
| To: | |
| Orr, Mark 301-251-7495 | |
| Shared Package | |
| ML100610025 | List: |
| References | |
| DG-1236 RG-1.068, Rev 2 | |
| Download: ML100610057 (4) | |
Text
3/2/2010 Response to Public Comments for Draft Regulatory Guide DG-1236, Initial Startup Test Program to Demonstrate Remote Shutdown Capability for Water-Cooled Nuclear Power Plants Proposed Revision 2 to Regulatory Guide (RG) 1.68.2 A notice that DG-1236 (proposed Rev. 2 to RG 1.68.2) was available for public comment was published in the Federal Register ( 74 FR 40629) on Wednesday, August 12, 2009. Consolidated industry comments were received in a letter from the Nuclear Energy Institute (NEI) signed by Mr. Russell Bell dated October 9, 2009. The U.S. Nuclear Regulatory Commission (NRC) has reviewed NEIs comments and prepared the following table of responses. The final version of revision 2 of RG 1.68.2 has been revised to address the comments as stated below.
Comments received from:
Russell J. Bell, Director, New Plant Licensing Nuclear Energy Institute 1776 I Street, NW Washington, DC 20006-3708 Phone: 202-739-8139 Comment No.
NEI Comment NEI Proposed Resolution NRC Resolution 1 - Sect. A, 3rd paragraph 1st sentence Criterion 1, Quality Standards and Records, is called out. This is really General Design Criterion 1.
For clarity, reword as General Design Criterion (GDC) 1, "Quality Standards and Records," of Appendix A to 10 CFR Part 50..."
Accepted. Sentence reworded.
2 - Sect. A 4th paragraph, 1st sentence Criterion XI, Test Control, is called out.
This is a Quality Assurance Criterion from 10 CFR Part 50, Appendix B.
For clarity, reword as Quality Assurance (QA) Criterion XI, Test Control, of Appendix B...
Accepted. Sentence reworded.
3 - Sect. A 4th paragraph, 2nd sentence This sentence starts with General Design Criterion (GDC) 19, Control Room...
This should be reworded to be consistent with changes above.
Reword as GDC 19, Control Room, of Appendix A to 10 CFR Part 50...
Accepted. Sentence reworded.
Response to public comments on DG-1236 3/2/2010 2
Comment No.
NEI Comment NEI Proposed Resolution NRC Resolution 4 - Sect. A 4th paragraph, 2nd sentence.
Revision 1 of RG 1.68.2 contains a footnote explaining that the term "hot shutdown" in GDC 19 corresponds to "hot standby" as defined in the Standard Technical Specifications (Mode 3 conditions). The term "hot standby" is then used throughout Rev. 1 of the regulatory guide. DG-1236 does not include that footnote and, instead, repeatedly uses the term "hot shutdown."
Use of the term "hot shutdown" without further explanation would create confusion since the Technical Specifications use "hot shutdown" for either Mode 3 or Mode 4.
To avoid confusion, the regulatory guide should specify that the first two objectives (shutdown and maintain the plant in hot shutdown) should be accomplished by demonstrating remote shutdown to Mode 3 conditions (reactor shutdown, but cooldown not required).
Then, to accomplish the third objective (cooldown), plants should show that they have the capability to achieve cold shutdown conditions (Mode 5 for most plants) from outside the control room.
This clarification could be achieved by adding the following footnote: "The term
'hot shutdown' used in GDC 19 and throughout this Regulatory Guide corresponds to Mode 3 conditions as described in the Standard Technical Specifications."
No change made to guide.
GDC 19 states: "Equipment at appropriate locations outside the control room shall be provided (1) with a design capability for prompt hot shutdown of the reactor, including necessary instrumentation and controls to maintain the unit in a safe condition during hot shutdown, and (2) with a potential capability for subsequent cold shutdown of the reactor through the use of suitable procedures."
GDC 19 is the regulation. The regulatory guide must be consistent with the regulation. The footnote in Revision 1 of RG 1.62.2 stating that the term "hot shutdown in GDC 19 corresponds to "hot standby" is not consistent with the regulation. It would create confusion with the standard technical specification definition on Mode 3 "Hot Standby" and Mode 4 "Hot Shutdown." The distinguish difference between Mode 3 and Mode 4 is the average reactor coolant temperature. Revision 2 of RG 1.62.2 is following the regulation and not trying to create confusion.
5 - Sect. C 1st Sentence The sentence starts with: The regulations in GDC 19 and Criterion XI require... This should be reworded to be consistent with changes above.
Reword as GDC 19 and QA Criterion XI require....
Accepted. Sentence reworded.
Response to public comments on DG-1236 3/2/2010 3
Comment No.
NEI Comment NEI Proposed Resolution NRC Resolution 6 - Sect. C.4, Demo. item d, 2nd sentence The sentence reads: This cooldown test should show that cold shutdown can be achieved from outside the control room.
This wording is not consistent with GDC 19 or Rev. 3 of RG 1.68, both [of] which address the potential capability for subsequent cold shutdown following a shutdown outside the control room to hot shutdown.
Reword to read: This cooldown test should show that the potential exists to achieve cold shutdown from outside the control room.
Accepted. Sentence reworded.
7 - Sect. C.4, Demo Item a.
Cooldown from Hot Shutdown to the point where core decay heat removal system (Residual Heat Removal in BWRs) from the remote shutdown system is accomplished using Safety Relief Valves. The vendor for these valves does not recommend operation of these valves at low pressure due to the potential for damage to the seating surface, which would require maintenance prior to the next startup. This recommendation is incorporated in the testing requirements for these valves in the plants Technical Specifications and should also be incorporated in this guidance.
Rewrite as follows:
- 4. The test should demonstrate that:
- a. The reactor coolant temperature and pressure can be lowered sufficiently to permit the operation of the core decay heat removal system that is to be ultimately used to place the reactor in a refueling shutdown mode. This demonstration should be performed with adequate steam pressure available to perform this test and avoid damaging equipment (e.g., Safety Relief Valves).
Acceptable. The following sentence has been added in parentheses:
(This demonstration should be performed with adequate steam pressure available to perform this test and avoid damaging equipment (e.g.,
Response to public comments on DG-1236 3/2/2010 4
Comment No.
NEI Comment NEI Proposed Resolution NRC Resolution 8 - Sect. C.4.
Last sentence This sentence reads: Personnel in excess of the minimum requirements may be present, provided the additional personnel perform only nonsafety-related activities that would not be required during an actual emergency shutdown.
This sounds like additional qualified operators could not be used during a real emergency even if they were present.
Revise the last sentence to read:
Personnel in excess of these identified in the remote shutdown procedure may be present during the demonstration, provided they do not perform activities needed to demonstrate the remote shutdown capability.
Agreed. Wording in guide revised.
However, NEIs proposed revision could create confusion or change the interpretation of the activities that the additional personnel may perform during the demonstration. NRC revised the sentence to read:
Personnel in excess of the minimum requirements may be present during the demonstration, provided that during the demonstration the additional personnel perform only nonsafety-related activities that would not be required during an actual emergency shutdown.
Because this same sentence appears as the last sentence to Section B.
Background and Section C.3, revise these sentences consistent with the above.
9 - Sect. C.5.
1st paragraph 2nd sentence This sentence refers to RG 1.16, Reporting of Operating Information, Appendix A, Technical Specifications. That RG was withdrawn on August 11, 2009 per 74 FR 40244. As an additional comment, the reporting guidance is not specific to the tests performed in DG-1236, but rather applies to all tests performed in the Startup Test Program (Post Fuel Load).
Replace with appropriate reference.
Agreed. The reference to RG 1.16 has been removed. The section is revised to read:
The licensee should retain the testing procedures and results from the hot and cold shutdown demonstration as part of the plants historical record. In addition, the historical record should include a summary of the testing in a startup report. This is consistent with RG 1.68 (Ref. 3).