ML20070M978
| ML20070M978 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 04/22/1994 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20070M975 | List: |
| References | |
| NUDOCS 9405040267 | |
| Download: ML20070M978 (4) | |
Text
_ f Mate p-.
4 UNITED STATES j
NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20566 4 001
,o
....+
r SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.
58 TO FACIL'ITY OPERATING LICENSE NO. NPF-58 THE CLEVELAND ELECTRIC ILLUMINATING COMPANY. ET AL.
PERRY NUCLEAR POWER PLANT. UNIT NO. 1 DOCKET NO. 50-440
1.0 INTRODUCTION
By letter dated September 28, 1992, the Cleveland Electric Illuminating Company, et al. (the licensee), requested an amendment to Facility Operating License No. NPF-58, for the Perry Nuclear Power Plant (PNPP), Unit 1.
The licensee proposed to eliminate the reactor protection system trip and the main steam line isolation valve (MSIV) closure requirements associated with the main steam line radiation monitors (MSLRM).
This amendment proposed changes to Technical Specification 2.2.1, Reactor Protection System Instrumentation Setpoints, TS 3.3.1, Reactor Protection System Instrumentation, and TS 3.3.2, Isolation Actuation Instrumentation.
2.0 EVALUATION On May 14, 1991, the NRC published a Safety Evaluation Report (SER) entitled
" Acceptance for Referencing of Licensing Topical Report NED0-31400, ' Safety Evaluation for Eliminating the Boiling Water Reactor Main Steam Line Isolation Valve Closure Function and Scram Function of the Main Steam Line Radiation Monitor (May 1987),'" in response to a Boiling Water Reactors Owners Group (BWROG) submittal of the topical report.
The NRC staff has reviewed and accepted Topical Report NED0-31400 on a generic basis provided the licensee satisfies the following three conditions:
1 1.
The applicant demonstrates that the assumptions with regard to input values (including power per assembly, Chi /Q, and decay times) that are made in the generic analysis bound those for the plant.
j 2.
The applicant includes sufficient evidence (implemented or proposed operating procedures, or equivalent commitments) to provide reasonable assurance that increased significant levels of radioactivity in the main steam lines will be controlled ex doses and environmental releases.peditiously to limit both occupational 3.
The applicant standardizes the MSLRM and offgas radiation monitor alarm setpoint at 1.5 times the nominal nitrogen-16 (N-16) background dose rate at the monitor locations. The applicant also commits to promptly sample the reactor coolant to determine possible contamination levels in the plant reactor coolant and the need for additional corrective actions, if the MSLRM or offgas radiation monitors or both exceed their alarm setpoints.
9405040267 940422 PDR ADOCK 05000440 P
j
,, In response to the first condition, the licensee used the PNPP short term (accident) diffusion estimates provided in the Updated Safety Analysis Report (USAR), Table 2.3-24, to determipe their Chi /Q value.
The USAR Chi /Q value of 0.00043 seconds / cubic meter (s/m ) for the PNPP control rod drop agcident (CRDA) was slightly higher than the NED0-31400 value of 0.0003 s/m. The licensee used the PNPP Chi /Q value in combination with PNPP design offgas system retention times and the other NED0-31400 input parameters to calculate doses for the CRDA assuming that the main steam line isolation valves (MSIVs) do not close. The whole body dose at the PNPP Exclusion Area Boundary (EAB) based on the assessment was calculated to be 0.003 rem. This value is significantly lower than the guidelines established in the NRC Standard Review Plan (SRP) Section 15.4.9.
Therefore, this deviation from the NEDO-31400 input values is acceptable.
The licensee also compared the PNPP source terms provided in USAR Table 15.4.13 to determine whether the values were consistent with the 18 source term inputs specified in NED0-31400. Two of the source terms used in NED0-31400 were smaller than the corresponding PNPP USAR source terms. The other 16 NED0-31400 source terms were either the same or a larger value than the corresponding PNPP USAR source terms.
The General Electric Company (GE) and PNPP reviewed all 18 source terms and determined that the overall NEDO source terms do bound the PNPP USAR source terms. Therefore, this deviation from the NED0-31400 input values is acceptable.
The licensee also noted that the power / rod value used in the PNPP USAR is 0.122 megawatts / rod (Mw/ rod) as compared to the value of 0.12 Mw/ rod used in NED0-31400.
The value used in NEDO-31400 is equivalent to the PNPP value rounded off to two significant figures.
This deviation does not invalidate the NED0-31400 analysis because the only use of the power / rod value in NED0-i 31400 was in the determination of the fission product source terms used in the radiological analyses which, as discussed above, bound the values used in the i
Therefore, this deviation from the NED0-31400 input i
values is acceptable.
In response to the second condition, the licensee reviewed the existing PNPP alarm response instructions (ARIs) and off-normal instructions (ONIs) to 4
verify that proper instructions are provided for the operators to respond to high radiation levels detected by the MSLRM and the off-gas pretreatment radiation monitor. The existing instructions for the response to an alarm from the off-gas pretreatment radiation monitor are considered adequate. The existing instructions for the response to an alarm from the MSLRM will be revised to include a requirement to sample the reactor coolant and to check the off-gas pretreatment radiation monitor for trends in radiation levels.
4 In response to the third condition, the licensee has committed to adjust the MSLRM alarm setpoint to 1.5 times the nominal 100 percent background reading at the monitor locations. However, with respect to the alarm setpoint for the off-gas pretreatment radiation monitor, the licensee has provided a technical justification for taking an exception to setting the alarm at 1.5 times the N-16 background level.
Because of the design of PNPP the N-16 levels at the off-gas pretreatment radiation monitor are extremely low. Other longer lived
~
i c e
,, radioactive isotopes provide the majority of the background radiation levels detected by the monitor.
Therefore, the N-16 background level is not an appropriate basis for setting the alarm for detecting fuel failures.
There are presently two alarms that are generated based on signals from the off-gas pretreatment radiation monitor; one alarm generates directly from the monitor and another generates from a recorder in the Control Room. The setpoint for the first alarm is addressed in the TS and is set at less than or equal to 0.358 Curies /second (Ci/sec). NED0-31400 assumed that a change in the off-gas release rate of 1 to 10 Ci/sec would be promptly alarmed.
l Therefore, the existing TS alarm setpoint would satisfy the assumption in NED0-31400.
If the TS alarm setpoint is exceeded, the TS requires the operators to take actions to restore the release rate to within the limit or to shut the plant down.
l The second alarm is typically set at 0.01 Ci/sec above the background dose rate or, if off-gas release rates exceed 0.075 Ci/sec, at 1.15 times the background release rate. This setpoint will cause annunciation of the alarm due to release rate increases much less than those assumed by the NED0-31400 document.
In addition, experience at PNPP has shown that the off-gas pretreatment radiation monitor can accurately detect and trend very minor fuel damage.
The licensee was able to detect leaks from two fuel rods in the first fuel cycle and from one bundle in the second cycle.
Therefore, because the proposed setpoints for the off-gas pretreatment radiation monitor will provide the operators with indications of fuel failures earlier than NED0-31400 assumed, these setpoints are acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Ohio State official was notified of the proposed issuance of the amendment.
The State official hr.d no comments.
4.0 ENVIRONMENTAL CONSIDERATION
This amendment involves a change to a requirement with respect to the instal-lation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 or a change to a surveillance requirement.
The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radiation exposure.
The Commission has previously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment on such finding (58 FR 598). Accordingly, this amendment meets 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 this amendment.
i
1
5.0 CONCLUSION
The staff has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and 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 this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: Andrew J. Kugler Date: April 22, 1994 Y