ML20205T168
| ML20205T168 | |
| Person / Time | |
|---|---|
| Site: | FitzPatrick  |
| Issue date: | 11/07/1988 |
| From: | Varga S Office of Nuclear Reactor Regulation |
| To: | POWER AUTHORITY OF THE STATE OF NEW YORK (NEW YORK |
| Shared Package | |
| ML20205T172 | List: |
| References | |
| GL-85-03, GL-85-3, NUDOCS 8811140158 | |
| Download: ML20205T168 (3) | |
Text
7590-1 UNITED STATES NUCLrAR REGULATORY COMMISSION In Patter of
)
POWEP AUTHORITY OF THE Docket No. 50-333 STATE OF NEW YORK i
I (James A. FitzPatrick
)
Nuclear Power Plant)
)
EXEMPTION, I.
Power Authority of the State of New York (the licensee) is the holder of Facility Operating License No. DPR-59, which authorizes operation of the James A.
g FitzPatrick Nuclear Power Plant Ithe facility). The license provides, among other things, that the facility is subiect to all rules, regulations and Orders of the Nuclear Regulatory Com.ission (the Ccmtssion) now or hereafter in effect.
The facility is a boiling water reactor located at f.ne licensee's site in Oswego County, New York.
II.
l 10 CFR Part 50.62(c)/4) requires that each boiling water reactor have a Standby Liquid Contml System (SI.CS) with minimum flow capacity equivalent in control capacity to 86 gallons per minute (gpm) with a boron concentration of 13 weight percent sodium pentaborate. The licensee proposes to use a minimum flow rate of 50 opm and a sodium pentaborate concentration of 11.5 veight percent. Therefore, an exerption from this regulation Os required. The sodium pentaborate solution used by the licensee will be.J:.:. up from boron enriched to 34.7 atom percent Roron 10 isotope.
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1
. The requirement established by the regulation was intended to provide for prompt injection of negative reactivity into a bniling water reactor pressure vessel in the event of an anticipated transient without scram (ATWS) event.
The reactor vessel size used to establish the required flow rate of 86 gpm and the sodium pentaborate concentration of 13 weight percent was the large 251-inch diameter vessel used in the PWR/5 and BWR/6 designs.
The FitzPatrick l
reactor has a much smaller, 218-inch diameter, vessel.
For the FitzPatrick reactor, a lesser flow rate will provide adequate shutdown margin in an ATWS event, equivalent to that called for by the regulation for the lareer 251-inch l
diameter boiline water reactor vessel. The use of enriched boron would allow a concentration lower than 13 weight percent and still provide an equivalent shutdown nargin.
Refer to Generic Letter 85-03 "Clarification of Equivalent Control Capacity for Standby Liquid Control Systems," January 28, 1985.
1 1
111.
l l
In this case, the injection flow rate and boron concentration will l
provide the equivalent level of control capacity for the smaller FitzPatrick l
reactor pressure vessel as that called for by the rule based on larger reactor pressure vessels.
Reouiring FitzPatrick to provide the flow rate-boron concentration capacity specified by the rule would not, in these particular I
ciNumstances, serve the underlying purpose of the rule.
The purpose of the rule is to reduce the risk frnm ATMS events by ensuring adecuate shutdown margin.
Thus, the Comission's staff finds that there are special circumstances in this case which satisfy the standards of 10 CFR Part 50.12(a)(2)(ii).
. IV.
As discussed above, the underlying purpose of the requirements of i
L paragraph (c)(4) of 10 CFR Part 50.62 is to ensure adequate shutdown margin in an ATWS event.
The underlying purpose is chieved and se**ted by an in.iection rate of 50 gpm of 11.5 weight percent sodium pentaborate solution.
Accordimly, the Comission has d: tennined that pursuant to 10 CFR Part 50.12(a), the Exemption, as described in Section III is authorized by law and will not present an undue risk to the public health and safety and is consi tent with common defense and security, and special circumstances are e
present for the Exemption, in that application of the regulation in these particular circumstances is not necessary to achieve the underlying purposes 1
Therefore, the Comission hereby grants the i
Exemption from paragraph (c)(4) of 10 CFR Part 50.62 to allow the use of an SLCS in.iection flow rate of 50 gpm of 11.5 weight percent sodium pentaborate solution, made up from boron enriched to 34.7 atom percent Boron-10 isotope.
j Pursuant to 10 CFR Part 51.32, the Comission has detennined that the i
granting of this Exemption will have no significant impact on the environment f
(53 FR 43954 ).
This Exemption is effective upon issuance.
La*ed at Rockville, Maryland, this 7 thday of November 1988.
FOR THE NUCLEAR REGULATORY COMMISSION O b Wj ' D rect Division of Reactor Pro,etts I/II Office of Nuclear Reactor Regulation