ML19317H156
| ML19317H156 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 09/10/1976 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19317H143 | List: |
| References | |
| NUDOCS 8004210622 | |
| Download: ML19317H156 (2) | |
Text
_____ _
.~
r
[ "Dy UNITED STATES Iq NUCLEAR REGULATORY COMMISSION f
S WASHINGTON, D. C. 20565 E
\\...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 14 TO FACILITY LICENSE NO. DPR-51 ARKANSAS POWER & LIGHT COMPANY ARKANSAS: NUCLEAR'ONE - UNIT NO. 1 DOCKET NO. 50-313 INTRODUCTION By letter dated June 28, 1976, Arkansas Power & Light Company (AP&L) requested changes to the Technical Specifications appended to Facility License No. DPR-51 for the Arkansas Nuclear Jne - Unit No.1 (ANO-1) facili ty.
The proposed changes involve establishing a +10 effective full power day (EFPD) band when changing between Figures 3.5.2-18 and 3.5.2-1C (Control Rod Withdrawal Limit curves) at 435 EFPD.
EVALUATION The control rod group withdrawal limits vs power curves (Figures 3.5.2-1B and 3.5.2-lC in the Technical Specifications) exist to assure that the fuel assembly maximum linear heat generation rate is not exceeded as a result of control rod pattern or movement during reactor operations.
The factors governing fuel power density and linear heat generation rate vary as a function of exposure and, hence, it is necessary to redefine control rod withdrawal limits as a function of exposure.
j AP&L is presently operating ANO-1 with control rod group withdrawal vs power limits that vary as a function of exposure.
One set of limits (Figure 3.5.2-1B) is valid for up to 435 and another set of limits is valid after 435 EFPD (Figure 3.5.2-1C). These limits are normally defined in the Technical Specifications such that the change of limits can occur over a time range (e.g., 435 EFPD +10) rather than on a specific EFPD.
'8004210
' This provides the licensee some flexibility in reducing the reactor power and making the change. The analyses which generate the curves in Figures 3.5.2-1B and 3.5.2-1C also considered the effect of such variations in exposure.
In the case of ANO-1, the exposure time range was not included in the original Technical Specifications. However, the analysis had been done to validate that the exposure variation of 110 EFPD for ANO-1 is acceptable and that the existing applicable limits can accomodate this exposure variation. AP&L has now determined that the time for limit change (435 EFPD) may occur at mid-week rather than during a lower power demand period and therefore has requested that the range of time considered in the analysis (110 EFPD) be included in the Technical Specifications to provide operating flexibility.
We have reviewed the original AP&L curves for AN0-1 and the proposed changes to those curves and concur that the exposure variation requested (~+10 EFPD) is consistent with the original analysis and is acceptable.
ENVIRONMENTAL CONSIDERATION We have determined that the amendment 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 impact.
Having made this determination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and pursuant to 10 CFR 551.5(d)(4) that an environmental impact statement, negative declaration, or environmental impact appraisal need not be prepared in connection with the issuance of this amendment.
CONCLUSION We have concluded, based on the considerations discussed above, that:
(1) because the changes do not involve a significant increase in the probability or consequences of accidents previously considered and do not ii;volve a significant decrease in a safety margin, the changes do not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Date: September 10, 1976 i
e
..~--
.