RBG-46314, Supplement to Amendment Request for a One Time Extension of the Drywell Bypass Test, Response to Request for Additional Information 2, River Bend Station, Unit 1
| ML042440634 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 08/26/2004 |
| From: | King R Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RBG-46314 | |
| Download: ML042440634 (5) | |
Text
-- Entergy Entergy Operations, Inc.
River Bend Station 5485 U. S. Highway 61 N St. Francisville, LA 70775 Fax 225 635 5068 RBG-46314 August 26, 2004 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Supplement to Amendment Request for a One Time Extension of the Drywell Bypass Test, Response to Request for Additional Information #2, River Bend Station, Unit 1 Docket No. 50-458 License No. NPF-47
REFERENCES:
- 1. Letter from Paul D. Hinnenkamp to USNRC Dated February 16, 2004 One-time Extension of the Drywell Bypass Test Interval, River Bend Station, Unit 1 (TAC No. MC2071)
- 2.
Supplement to Amendment Request Dated June 8, 2004, for a One Time Extension of the Drywell Bypass Test, Response to Request for Additional Information (TAC No. MC2071)
Dear Sir or Madam:
By the letter referenced above, Entergy Operations, Inc. (Entergy) proposed a change to the River Bend Station, Unit 1 (RBS) Technical Specifications (TSs) to extend the Drywell Bypass Test interval on a one-time basis.
On July 14, 2004, Michael K. Webb forwarded a Request for Additional Information to Entergy. There were 2 questions. Entergy's response is contained in Attachment 1.
There are no technical changes proposed. The original no significant hazards consideration included in the above reference is not affected by any information contained in the supplemental letter. There are no new commitments contained in this letter.
If you have any questions or require additional information, please contact Bill Brice at 601-368-5076.
- D.) 0
RBG-46314 Page 2 of 2 I declare under penalty of perjury that the foregoing is true and correct. Executed on August 26, 2004.
Sincerely, Rick J. King Director, Nuclear Safety Assurance River Bend Station, Unit 1 RJKIWBB Attachments:
- 1. Response to Request For Additional Information cc:
Dr. Bruce S. Mallett U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011 NRC Senior Resident Inspector P. 0. Box 1050 St. Francisville, LA 70775 U.S. Nuclear Regulatory Commission Attn: Mr. Michael K. Webb MS O-7D1 Washington, DC 20555-0001 Louisiana Department of Environmental Quality Office of Environmental Compliance Attn: Mr. Prosanta Chowdhury Surveillance Division P. 0. Box 4312 Baton Rouge, LA 70821-4312
Attachment I To RBG-4631 4 Response to Request for Additional Information to RBG-46314 Page 1 of 2 Response to Request for Additional Information Related to a One-Time Extension of the Drywell Bypass Test Question 1:
Section 5.0 of the Attachment to the February 16, 2004, submittal discusses a qualitative assessment of the leaktightness of the drywell that is performed each cycle. The assessment involves trending the drywell and containment pressures. Provide a description of the assessment, including the differential pressures, hold times, and leakage acceptance criteria.
Response 1:
The Drywell (DW) Leak Tightness Assessment is performed once each operating cycle during plant operation to satisfy commitment 13949 in an RBS Letter to the NRC, RBG-42264 dated 12/12/95. Because of normal air system leakage in containment, RBS must periodically purge the containment. The DW Leak Tightness assessment is performed following a containment purge. Venting is secured at a DW to containment differential pressure of 0.26 PSID. The differential pressure is then recorded at 5 minute intervals for at least 35 minutes.
The differential pressure drop vs. time test result is then evaluated against the acceptable pressure drop versus time curve used for the DW Bypass Leakage Rate Test.
Question 2:
The drywell bypass tests and inspections complement each other in ensuring the structural and functional integrity of the drywell and containment. The amendment request does not provide information related to the structural and functional integrity of the drywell. Describe the results of the most recent inspections of the drywell boundary, including the type of inspections and description of any significant degradations, the root cause(s), and corrective actions taken.
Response 2:
A walk down and visual inspection of the interior and exterior is done to verify the structural integrity of the DW. This is done to satisfy Technical Specifications SR 3.6.5.1.4. The inspection is done during shutdown and immediately prior to the Integrated Primary Containment Leak Rate Test (ILRT). The procedure used to perform the walk down gives specific instructions and acceptance criteria. The inspection includes wall, coatings, concrete damage, penetrations, imbedded steel anchor plates, welds, access hatches, etc. The results are recorded including a general appearance description. The results are also reviewed by Civil Structural Engineering. The last walk down was performed during shutdown in October 1997. The ILRT was not performed during this outage (RF-07).
In addition to this inspection, a Drywell Coating Inspection is done every outage. An engineer from the Piping/Civil group participates in the task to perform on the spot characterization of findings and to update the coatings tracking log in accordance with the protective coatings to RBG-46314 Page 2 of 2 procedure. It is not unusual to find failed coating or light rust during this inspection. Work orders are initiated to repair these problems.
No structural integrity concerns have been identified during any of these inspections.