ML20211N606
| ML20211N606 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 02/20/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20211N605 | List: |
| References | |
| NUDOCS 8703020145 | |
| Download: ML20211N606 (4) | |
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UNITED STATES 0"
i NUCLEAR REGULATORY COMMISSION h
j WASHINGTON, D. C. 20555 s
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.1 TO FACILITY OPERATING LICENSE NO. NPF-55 ILLIN0IS POWER COMPANY S0YLAND POWER COOPERATIVE, INC.
WESTERN ILLIN0IS POWER COOPERATIVE, INC.
DOCKET NO. 50-461 CLINTON POWER STATION, UNIT NO. I
1.0 INTRODUCTION
By letter dated January 20, 1987, Illinois Power Company, Soyland Power Cooperative, Inc., and Western Illinois Power Cooperative, Inc. (the licensees) requested an amendment to Facility Operating License No. NPF-55 for the Clinton Power Station, Unit No. 1.
The proposed amendment would increase the Clinton control room heating ventilating and air conditioning (HVAC) system air flow rate to 64,000 cfm 210% from the currently specified 62,500 cfm 10%. The proposed new air flow rate is based on the pre-opera-tional flow test results with the as-built configuration of the control room HVAC system.
2.0 EVALUATION The control room HVAC system consists of two fully redundant trains of air conditioning units, recirculation filter units, fans, humidifiers, ductwork and isolation dampers. Each train has a parallel 4000 cfm standby makeup air filtration unit containing fans, electric heaters, demisters, high efficiency particulate air filter (HEPA), and charcoal adsorbers. The Control Room HVAC system is designed to maintain the control room under a positive pressure with a suitable environment for equipment operation and safe occupancy of the control room under all plant operating conditions.
In the current version of the Clinton Final Safety Analysis Report (FSAR)
(through Amendment No. 38) the licensee has identified 62,500 cfm as the desion air flow rate throuoh the recirculation air filter unit in the control room HVAC system. 'This air flow rate (62,500 cfm *10%) is based on calculated air flows using expected flow resistance in the system.
This value was subsequently used in the Clinton Technical Specifications as a preliminary value. A measured value was not available, since pre-operational flow tests on the as-built control room HVAC system were not performed prior to issuance of the Low Power Operating License. As indicated in Supplement No. 7 to the Clinton SER, the tests were deferred until prior to initial criticality. The proposed 64,0C0 cfm 10% air flow rate is representative of the as-built configuration of both trains of the control room HVAC system.
It is based on the results of the pre-operational air flow tests that since have been performed.
8703020145 070220 PDR ADOCK 05000461 p
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. The recirculation air flow rate through the filter unit is directly proportional to the iodine protection factor (IPF). The increased air flow rate from 62,500 cfm to 64,000 cfm (at the same inleakage rate and filter efficiency) raises the IPF by approximately 2 percent. Therefore, the proposed increase of recirculation air flow rate is more conservative and does not relax the current requirements for protection of the control room operators as required in General Design Criterion 19 of Appendix A to 10 CFR 50. Hence, we find that the proposed change is acceptable.
3.0 FINAL NO'SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION State Consultation In accordance with the Commission's regulations, con'sultation was held with the State of Illinois, Department of Nuclear Safety by telephone.
The State had no comment on this proposed amendment.
Response to Coments No comments were received in response to the Federal Register Notice of January 27, 1987 (52 FR 2812).
No Significant Hazards Consideration Determination The Commission's regulations in 10 CFR 50.92 state that the Comission may make a final determination that a proposed license amendment involves no significant hazards considerations if operation of the facility in accordance with the proposed amendment would not:
(1)
Involve a significant increase in the probebility or consequences of an accident previously evaluated; or (2) Create the possibility of a new or different kind of accident from any accident previously evaluated; or (3)
Involve a significant reduction in a margin of safety.
The thyroid dose for control room operators resulting from the proposed increase in the control room HVAC flow rate has been recalculated. The proposed increase in the system flow rate results in a slight decrease in calculated thyroid dose to control room operators due to recirculating a higher percentage of control room air through the filter unit (charcoal adsorbers). Therefore, this proposed amendment does not involve a signifi-cant increase in the consequences of an accident previously evaluated.
Since there is no change in equipment or procedures for this system this change does not involve a significant increase in the probability of an accident previously evaluated.
There are no changes to plant equipment or plant procedures, except for procedures test acceptance criteria. The only affect of the change on plant safety is the small improvement in the iodine protectico factor and the slight decrease in chloride removal capability. These affects are enveloped by previously evaluated accidents. The amendment does not create the possibility of a new or different kind of accident from any accident previously evaluated.
. Although the proposed amendment will result in an increase in the control room HVAC system flow rate to 64,000 cfm, the initial control room design I
was for a two unit control room utilizing a recirculation flow rate of l
approximately 71,000 cfm. The increased flow rate will result in an overall decrease in thyroid dose and a slight decrease in chloride removal i
(approximately 2%) from the values described in the Final Safety Analysis Report. The slight decrease in chloride removal capability is still well within acceptable limits. Therefore, this change does not involve a significant reduction in the margin of safety.
The staff has detennined, based on the review of the licensee's submittal that operation of the facility in accordance with the proposed amendment would not involve a significant reduction in the margin of safety and that:
(1) Operation of the facility in accordance with the proposed amendment would not significantly increase the probability or consequences of an accident previously evaluated.
(2) Operation of the facility in accordance with the proposed amendment would not create the possibility of a new or different kind of accident from any accident previously evaluated.
(3) Operation of the facility in accordance with the proposed amendment would not involve a significant reduction in a margin of safety.
Therefore, the staff concludes that this amendment involves no significant hazards considerations.
4.0 ENVIRONMENTAL CONSIDERATION
This amendment involves a change to a requirement with respect to the installation or use of a facility component located witbin the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no significant increase in the amounts, and no signifi-cant 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 made a final no significant hazards consideration finding with respect to this amendment.
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 nor environmental assessment need be prepared in connection with the issuance of this amendment.
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, and 1
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. (2) such activities will be conducted in compliance with the Comission's regulations and the issuance of this amendment will not be inimical to the common defense and the security nor to the health and safety of the public.
Prinicipal Contributor:
J. Lee Dcted: February 20, 1987 i
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