ML19262A728
| ML19262A728 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/19/1979 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19262A726 | List: |
| References | |
| NUDOCS 7912100427 | |
| Download: ML19262A728 (2) | |
Text
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,,o= u coq'o, tnJITED STATES f '.i -:- ( [ i NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 i#75 iA4,h/jr5 s.'
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REGARDING CEA GUIDE TUBE INTEGRITY FOR CYCLE 3 OPERATION RALTIMORE GAS AND ELECTRIC COMPANY CLAVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO. 2
- DOCKET NO. 50-318 Introduction On October 21, 1978, the Commission is.c.ued Amendment No.18 to Facility Operating License No. DPR-69 for Calvert Cliffs Nuclear Power Plant, Unit No. 2 (CCNPP-2). This amendment authorized operation for Cycle 2 with modified (sleeved and reduced flow) guide tuces for the Control Elemer.t Assemblies (CEAs) and made the necessary changes to the Technical Specifi-cations.
By letter dated July 11, 1979, Baltimore Gas and Electric Company (BG&E or the licensee) notified the NRC staff that the Cycle 3 reload core would be designed to perform within the current Cycle 2 design parameters, Technical Specifications and related bases, and current setpoints and that there will be no unreviewed safety questions as defined by 10 CFR 50.59 involved with the Cycle 3 reload core design. We notified BG&E that since the Safety Evaluation for Amendment No. 18 concluded the CEA guide tube integrity was acceptable for Cycle 2 operation only, a Safety Evaluation for Cycle 3 operation would be required.
The letter transmitting Amendment No.18 documented BG&E's commitment to provide a CEA guide tube evaluation prngram 90 days prior to the shutdown for the Cycle 3 reload outage.
Such a program was submitted on September 7, 1979.
Our review resulted in a request for additional information dated September 20, 1979. The BG&E response was receivad on October 10, 1979.
By letter dated November 12, 1979, BG&E provided the results of the CEA and CEA guide tube inspection program performed during the Cycle 3 reload outage. This Safety Evaluation documents our review.
,rn7 r,
Ciscussion and Evaluation 1J2]
J2 The CEA guide tubes in a total of 128 irradiated fuel assemblies and 5 CEAs were inspected during the Cycle 3 refueling putage.
No significant wear was observe; on any of the guide tu:e sleeves.
The slight burnishings observed on :ne control rods were common to CEAs located in both sleeved and unsleeved fuel assemblies.
The fuel assemblies whien had been irradiated prior to sieeeir.; in tne 1978 Cycle 2 refueling outage exhibited undersized crimos rela:i.e to Comcastion Engineering's (CE's) acceptance criteria.
- However,
.i' : sits en 5 number of these assenblies w"ich were discharged to tne Erte: "
e'.
00; snowed no axial movemen Of :ne sleeves.
Therefore, :nese 7 9121 O p tf.2L J'
tests provided additional confirmation on the conservatism of the acceptance criteria used to determine crimp adequacy.
Those assemblies in this category which were returned to CEA locations were recrimped. Thus, the crimp size for all fuel assemblies returning to CEA locations were determined and found to exceed the CE crimp c iteria.
Based on the magnitude of the crimp size, the licensee nas proposed elimination of the CE recommended restriction on control rod movement below coolant temperatures of 400 F.
We are in agreement with this recommendation.
Based on the results of the CEA guide tube inspection program performed at CCNPP-2 during the Cycle 3. refueling outage, we find continued use of the sleeved guide tubes acceptable for Cycle 3 operation of CCNPP-2.
This approval includes the colitinued use of previously sleeved fuel assemblies and the use of newly sleeved fuel assemblies as descr'Mi in the BG&E submittals.
BG&E and CE have not proposed the use of the reduced flow demonstration assemblies in CEA locations during Cycle 3.
Prior to reuse of these demonstration assemblies in CEA locations, the licensee will further evaluate the inspection results.
We find this approach acceptable.
BG&E has agreed to submit their CEA guide tube evaluation program for NRC review at least 90 days prior to the CCNPP-2 shutdown for the Cycle 4 reload outage.
E nvironmental Consideration We have determined that this evaluation does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental imoact.
Having made this determination, we have further concluded that this action is insignificant from the standpoint of environmental impact and pursuant to 10 CFR 51.5(d)(4) tnat an environmental impact statement or negative declaration and environmental impact appraisal need not be prepared.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the evaluation does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the action does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will net be endangered by speration in the proposed manner, anc (3) such activities will be ccnductec in :ompliance witn the Commissicr's regulations and the action will not be inimical to the commor defense and security or to the health and safety of the public.
Nce-- November 19, 1979 1523 033