ML15275A143
| ML15275A143 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 10/02/2015 |
| From: | Richard Guzman Plant Licensing Branch 1 |
| To: | Craft W Dominion Nuclear Connecticut |
| Guzman R | |
| References | |
| GL-08-001, TAC MF5715, TAC MF5716 | |
| Download: ML15275A143 (2) | |
Text
1 Guzman, Richard From:
Guzman, Richard Sent:
Friday, October 02, 2015 10:50 AM To:
Wanda D Craft (Generation - 6)
Subject:
Millstone 2&3 TSTF-523, Revision 2, GL 2008-01, Managing Gas Accumulation -
Follow-Up Request for Additional Information
- Wanda, The NRC staff has reviewed the information provided in the subject license amendment request dated January 15, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML15021A128),
as supplemented by letters dated April 15, July 16, and July 30, 2015 (ADAMS Accession No. ML15111A449, ML15202A125 and ML15216A365, respectively), and has determined that additional information is needed to complete its review. Shown below is the NRC staffs follow-up request for additional information (RAI) questions. The information was discussed with your staff on October 1, 2015. As agreed, please provide your formal response by November 2, 2015. Please contact me if you have any questions.
REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO ADOPT TSTF-523, REVISION 2, GL-2008-01, MANAGING GAS ACCUMULATION TAC NOS. MF5715 AND MF5716 The NRC staff transmitted a request for additional information (RAI) to Dominion Nuclear Connecticut, Inc.
(DNC) on June 1, 2015 (ADAMS Accession No. ML15152A532). The NRC staff has reviewed the information provided in DNCs RAI response dated July 16 and 30, 2015, and has determined that additional information is needed to complete its review.
RAI 4 requested a description of the monitoring of system parameters that could identify a change that could introduce gas into piping between surveillance intervals. The July 16, 2015, DNC response addressed accumulators but did not address other potential sources of gas. Please provide the monitoring frequency and the response to a malfunction that could introduce gas into a system that is important to safety for the following systems/equipment during power operation:
- b. Chemical sampling system
- c. Any other equipment where a malfunction could introduce gas into a system that is important to safety RAI 9 requested specified detail regarding the void surveillance history of Millstone Power Station, Unit 2 (MPS2). Please address the following:
- a. DNC identified a void discovery on August 13, 2013, but there is no entry in the table of void discoveries for this date.
- b. 92-day surveillances were identified on May 21, 2013 and May 16, 2014 where the measured void volumes of 6.557 ft3 and 5.286 ft3 exceeded the volume that was predicted to exceed the operable limit of 2.57 ft3. The first was attributed to accumulator leakage and the second to an improper fill and vent after a refueling outage (RFO). Why were these not identified earlier by daily monitoring of accumulator
2 level and immediate follow-up after an outage, respectively? Have DNC procedures been changed to correct these occurrences?
- c. A void volume of 0.122 ft3 was measured versus a 0.129 ft3 criterion during a 92-day surveillance on July 28, 2014. This was attributed to outgassing after shutdown cooling termination following an RFO. All other similar occurrences resulted in smaller volumes. Please provide information to substantiate this large outgassing volume.
RAI 9e requested the MPS2 void surveillance history related to Monitoring of equipment such as accumulators or reactor coolant system leakage and follow-up from outages with respect to void assessment. Please describe the surveillances that have been conducted when exiting an outage and the surveillances that have been conducted prior to a return to power operation.
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RichGuzman Sr.ProjectManager NRR/DORL USNRC 3014151030