ML20133N428
| ML20133N428 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 07/16/1996 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20133N425 | List: |
| References | |
| NUDOCS 9701230288 | |
| Download: ML20133N428 (4) | |
Text
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t UNITED STATES j
NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. anans anni
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT N05.171 AND 175 TO FACILITY OPERATING LICENSE NOS. DPR-24 AND DPR-27 WISCONSIN ELECTRIC POWER COMPANX POINT BEACH NUCLEAR PLANT. UNIT NOS. 1 AND 2 4
DOCKET NOS. 50-266 AND 50-301
1.0 INTRODUCTION
By letter dated February 8,1996, as supplemented August 15, December 2, December 19, 1996, and January 6, 1997, Wisconsin Electric Power Company (WEPC0, the licensee) requested amendments to the Technical Specification (TS) appended to Facility Operating License Nos. DPR-24 and DPR-27 for the Point Beach Nuclear Plant (PBNP), Unit Nos. I and 2.
The proposed amendments would change Section 15.3.10, " Control Rod and Power Distribution Limits," to improve the clarity of this section. The licensee also proposed a surveillance change to Section 15.4.1.
The above referenced changes are carried out in accordance with the guidance provided in NUREG-1431, "The Westinghouse Owner's Group Improved Standard Technical Specifications (ISTS),"
Revision 0.
The staff reviewed the proposed amendment for consistency with NUREG-1431, Revision 1.
References to the licensee's submittal for NUREG-1431 relate to Revision 0 whereas references to NUREG-1431 in staff conclusions relate to Revision 1.
Specification 15.3.10, " Control Rod and Power Distribution Limits," ensures core subcriticality following a reactor trip; it places a limit on possible reactivity insertion due to a hypothetical rod cluster control assembly (RCCA) ejection, and it also ensures an acceptable core power distribution exists i
during normal power operations. The letters dated August 15, December 2, December 19, 1996, and January 6, 1997, provided clarifying information and updated TS pages that were within the scope of the original application and did not change the NRC staff's initial proposed no significant hazards cor. sideration determination.
2.0 EVALUATION The current shutdown margin TS at the Point Beach Nuclear Plant does not stipulate a time limit at which time operators would start to borate as necessary to restore the shutdown margin to the value specified in the TS.
The change requested by WEPC0 would add an action statement to the TS requiring the operators to initiate boration within 15 minutes to restore shutdown margin requirements. This is consistent with NUREG-1431, and the staff finds this administrative change acceptable.
9701230289 970116 PDR ADOCK 05000266 P
. The safety analyses associated with a reactor trip assumes operability of shutdown and control rods.
If one or more of the rods were determined to be inoperable, the possibility exists that the shutdown margin may be affected.
If the shutdown margin requirements are not met, boration is initiated.
However, at the present time, there is no time limit imposed on how long it should take to recover the shutdown margin. The change requested by the licensee would put a 1-hour time limit to accomplish / recover the shutdown margin. The time to recover the shutdown margin did not previously appear in the PBNP TS. However, the proposed 1-hour limit is consistent with NUREG-1431 and is more restrictive than the existing TS. The staff finds this change acceptable.
Rod misalignment is also part of the safety analyses associated with power distributions and shutdown margin. Should a rod misalignment occur, the operators are required to restore the misaligned rod to within the alignment
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limits within 1-hour.
If this is not possible, the thermal power is reduced to less than or equal to 75 percent power within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. This time period is consistent with the existing TS for PBNP.
The F (z) and F( must be verified within their limit during continued operaIionwithamisalignedrod. When a control rod is misaligned, the assumptions that are used to determine the rod insertion limits, axial flux difference limits, and quadrant powcr tilts limits are not preserved.
Conseguently, peaking factor limits may not be preserved.
As a result, F and F" must be verified by incore mapping. These proposed revisions are,(z) consisTentwiththerequirementsofNUREG-1431andwillimposestricter requirements than those imposed by the existing TS.
The licensee also made changes (added additional requirements) to the control 4
rod position indication system to make the specifications consistent with those of NUREG-1431.
The licensee proposed changes associated with bank insertion limits. The licensee proposed that the operator be required to verify that the shutdown a
margin is within limits within the span of an hour or initiate boration to restore the shutdown margin within 1-hour. The licensee also proposed that the shutdown banks be fully withdrawn within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
If these actions cannot be perfoneed, the operator will put the reactor in hot standby within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The staff finds these changes acceptable since they enhance the safety function at P8NP.
Similarly, the licensee proposes to add requirements to the TS concerning operator actions should the control banks insertion limits be violated. The proposed changes would require that the operator restore the control banks to within limits within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. These changes are more restrictive than the existing TS and therefore are acceptable.
The licensee also proposed changes (added actions) when monitoring the heat flux hot channel factor and the nuclear enthalpy hot channel factor.
The j
proposed additional actions would delineate specific operate-action that must be performed, including power reductions and readjustments of any reactor i
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L ED O protection system setpoints. The proposed changes are more prescriptive and will enhance the clarity of the TS. An additional change was required to modify the Note 20 for TS Table 15.4.1-1 to reflect the correct TS reference as 15.3.10.E instead of 15.3.10.B.
The proposed additional actions are consistent with NUREG-1431. The staff finds the proposed changes acceptable.
Current TS are in place at PBNP to prevent the limits on axial flux difference from being exceeded. Operator actions are being rewritten to more clearly define required operator actions.
Changes are proposed regarding the quadrant power tilt.
If the quadrant power tilt exceeds 2 percent with thermal power greater than or equal to 50 percent of rated power, the licensee proposed to reduce power greater than or equal to 2 percent from rated thermal power for each 1 percent of indicated power tilt, reevaluate safety analyses and confirm results remain valid for duration of operation under this condition and within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and once per 7 days g
are with TS 15.3.10.E.1.a limits. This is thereafter, verify F (z) and F, t PBNP and additional actions are being added a
consistent with the current TS a to the TS in accordance with the guidance suggested in NUREG-1431. The limitations imposed en the heat flux hot channel factor and the enthalpy rise hot channel factor will ensure that the core power distributions are maintained within design limits. An administrative change was made to relocate the monthly surveillance requirements for the hot channel factors to TS Table 15.4.1-2.
The proposed chenges are acceptable to the staff.
During pnysics testing, current PBNP TS do not identify the plant conditions that must be maintained during at-power or low-power physics testing. The licensee is proposing to add two sections to TS Section 15.3.10 to specify which conditions must be maintained, and which requirements may be suspended during the performance of these tests, and what actions should be taken should any of these required plant conditions be violated. These additions to the TS will enhance the TS by providing guidance to plant operators in an area where none currently exists. The licensee also added to TS Section 15.4.1-2 a daily surveillance of shutdown margin during the low power physics testing.
The proposed changes are consistent with the guidance contained in NUREG-1431.
The staff finds these changes acceptable.
The licensee has revised TS 15.3.10.H to identify the actual plant conditions when the actual drop times for the RCCAs are performed.
Typically, RCCA drop times must be no greater than 2.2 seconds. The licensee is revising the TS to require actions be taken should a drop exceed 2.2 seconds. These actions are identical to those currently being performed at PBNP.
The staff finds these revisions acceptable.
Finally, the licensee requests a change to the bases of Section 15.3.10 to reflect the modifications made to the TS and incorporate the information associated with the new proposed additions. The added background information is consistent with bases information in NUREG-1431.
The staff agrees with the requested change.
.... 3.0 ETATE CONSULTATION In accordance with the Commission's regulations, the Wisconsin State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
These amendments change a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and change a surveillance requirement.
The staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluent that may be released offsite, and that there is no significant increase in individual or cumulatite occupational radiation exposure. The Commission has previously published a proposed finding that these amendments involve no significant hazards consideration and there has been no public comment on such finding (61 FR 10398). Accordingly, these amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of these amendments.
5.0 CONCLUSION
The staff has concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health ar.a safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the nealth and safety of the public.
Principal Contributor: Anthony Attard Date:
January 16, 1997