ML102861724
| ML102861724 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 10/13/2010 |
| From: | Kalyanam N Plant Licensing Branch IV |
| To: | David Bice, Clark R Entergy Nuclear Operations |
| Kalyanam N, NRR/DORL/LPL4, 415-1480 | |
| References | |
| TAC ME4563 | |
| Download: ML102861724 (3) | |
Text
From:
Kalyanam, Kaly Sent:
Wednesday, October 13, 2010 12:28 PM To:
BICE, DAVID B; CLARK, ROBERT W Cc:
Lent, Susan; Burkhardt, Janet
Subject:
Request for Additional Information - LAR Regariding Completion Times for One Inoperable Reactor Coolant System Cooling Loop, ANO-1
SUBJECT:
Changes to Technical Specification Related to Completion Times for One Inoperable RCS Cooling Loop - Request for Additional Infoemation.
TAC No.: ME4563 LICENSEE: Entergy Operations Inc.
PLANT: Arkansas Nuclear One, Unit 1 DOCKET NO.: 50-313 Dave/Bob, By letter dated August 24, 2010, Entergy Operations, Inc. (Entergy) made application to amend the Technical Specifications (TS) of the Arkansas Nuclear One, Unit 1 (ANO-1).
The proposed amendment would revise several Technical Specifications (TS) 3.4.6, RCS Loops - Mode 4, TS 3.4.7, RCS Loops - Mode 5, Loops Filled, TS 3.4.8, RCS Loops - Mode 5, Loops Not Filled, and TS 3.9.5, Decay Heat Removal (DHR) and Coolant Circulation - Low Water Level. to permit a greater time period for one of two required Reactor Coolant System (RCS) cooling loops to be inoperable. The affected TSs are applicable in lower Modes of Operation (Modes 4, 5, and 6).
The NRC Staff has reviewed the amendment request and determined that we require additional information to complete our review. A request for additional information appears below.
The staff requests you to provide a response to the RAI within 30 days from the date of this email. If this is not feasible, please let me know, in advance, when the response will be sent.
Thanks Kaly REQUEST FOR ADDITIONAL INFORMATION ENTERGY OPERATIONS, INC.
ARKANSAS NUCLEAR ONE, UNIT 1 DOCKET NO. 50-313
LICENSE AMENDMENT REQUEST REGARDING COMPLETION TIMES FOR ONE INOPERABLE REACTOR COOLANT SYSTEM COOLING LOOP
- 1. Discuss plant procedures and operator training programs to show that the in-service reactor coolant system (RCS) loop or decay heat removal (DHR) loop, as applicable, will not be adversely affected by outage activities and surveillance tests in Modes 4, 5, and 6.
- 2. Discuss alternate core cooling (ACC) methods that can be used for DHR and RCS inventory control during a total loss of the RCS loops and DHR loops event for the following applicable plant conditions: (1) the plant is in Mode 4 (TS 3.4.6 conditions); (2) the plant is in Mode 5 and the RCS loops are filled with water (TS 3.4.7 conditions); (3) the plant is in Mode 5 and the RCS loops are not filled with water (such as mid-loop operations - TS 3.4.8 conditions); and (4) the plant is in Mode 6 with the water level less than 23 feet above the irradiated fuel seated in the reactor pressure vessel (TS 3.9.5 conditions). The requested information should show that: (1) the ACC methods are effective to remove the decay heat and maintain the plant in safe and stable conditions for an extended period of time; (2) the associated operating procedures are available; and (3) the procedures are technically sound and provide clear guidance to the operator for applying the methods. In addition, provide a discussion of plant administration controls, programs or procedures to assure that the equipment (pumps, valves, and instrumentation) needed for the ACC methods is operable.
- 3. Discuss the method used for the time-to-boil calculations and address the acceptability of the method used. If the method used was previously approved by the NRC, address the compliance with the conditions and restrictions specified in the NRC safety evaluation report approving the method. The requested information should include the plant parameters considered in the calculations for Modes 4, 5 and 6 conditions, identify the major input initial conditions, discuss the bases used to select the numerical values of the input parameters and demonstrate that the numerical values (with consideration of the uncertainties and fluctuation around the nominal values) are conservative, resulting in a minimum time-to-boil. For TS 3.9.5 - Mode 6 conditions, specify and provide the bases for the amount of the water in the refueling pool cavity above the reactor vessel used in the time-to-boil calculation considering that the refueling cavity water may not be completely mixed. Also, provide the results of the calculated time-to-boil as a function of the key parameters that will have an effect on the calculated time-to-boil for use in implementation of the proposed changes to TSs 3.4.7, 3.4.8 and 3.9.5.
E-mail Properties Mail Envelope Properties (94A2A4408AC65F42AC084527534CF41618633228C0)
Subject:
Request for Additional Information - LAR Regariding Completion Times for One Inoperable Reactor Coolant System Cooling Loop, ANO-1 Sent Date: 10/13/2010 12:28:15 PM Received Date: 10/13/2010 12:28:15 PM From: Kalyanam, Kaly Created By: Kaly.Kalyanam@nrc.gov Recipients:
DBICE@entergy.com (BICE, DAVID B)
Tracking Status: None RCLARK@entergy.com (CLARK, ROBERT W)
Tracking Status: None Susan.Lent@nrc.gov (Lent, Susan)
Tracking Status: None Janet.Burkhardt@nrc.gov (Burkhardt, Janet)
Tracking Status: None Post Office:
HQCLSTR01.nrc.gov Files Size Date & Time MESSAGE 20205 10/13/2010 Options Expiration Date:
Priority: olImportanceNormal ReplyRequested: False Return Notification: False Sensitivity: olNormal Recipients received: