ML20056A676
| ML20056A676 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 08/03/1990 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20056A673 | List: |
| References | |
| NUDOCS 9008090011 | |
| Download: ML20056A676 (2) | |
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UNITED STATES I
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NUCLEAR REGULATORY COMMISSION a
WASHING TON, D. C. 20555 3
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REAC79R REGULATION RELATED TO AMENDMENT NO. 43 TO FACILITY OPERATING LICENSE NO. NPF-62 ILLIN0IS POWER COMPANY, ET AL.
CLINTON POWER' STATION, UNIT NO. 1 DOCKET NO. 50-461 o
1.0 INTRODUCTION
By. letter dated April 25, 1990, the Illinois Power Company (IP), et al. (tke licensees) requested an amendment to Facility Operating License No. NPF-62 for the Clinton Power Station,, Unit 1.
The proposed amendment would revise
- the SURVEILLANCE REQUIREMENTS to Technical Specification 4.9.6.1 for the t
refueling platform main-hoist, and the SURVEILLANCE REQUIREMENTS of Technical Specification 4.7.4 to apply a consistent methodology for increasing the sample size for snubber functional inspections, for all three types of sampling plans.
2.0 EVALUATION At Clinton, the main hois' installed on the refuelinkst currently consists platform is utilized L
-to move fuel inside the rtactor vessel. The main ho 1
of a three segment, open f rame, triangular mast (General Electric Model
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p NF400). -To-improve contamination control and to increase the rigidity of L
lthe mast, so as to-improve the licensee's ability to precisely locate the i
hoist over the proper fuel assembly, the licensee is replacing the Model NF400 mast with a Model NF500 mast.
The Model NF500 is a three segment, solid, cylindrical telescoping mast.
The utilization of this new mast will not affect the function nor operation 1
L of the main hoist of the refueling pi dform. The auxiliary hoists of' the L
refueling platform will also remain unchanged.
However, the new mast does
- weigh more than the previous mast; consequently, certain overload and interlock
' load limits must be revised,-as these' load limits utilized the weight of the mast in the establishment of the limits.
Three setpoints would be revised. The first setpoint deals with the main hoist. overload cutoff being raised from 1200
- 50 to 1600 50 pounds. This
. increased value is still bounded by the 39 load. limit of 2000 pounds lifting force for fuel bundle damage.
The second and third setpoints deal with main hoist, loaded-interlock. They are being raised from 485 50 and 550 1 50 to 700 50 pcunds. These interlocks are activated when a fuel assembly is suspended from the mast and prevent certain movements of the refueling machine and withdrawal of control rods. These increased values are due to the higher weight of the new mast and the two inter'ocks are being set to the same value as they are both required to be activated when a fuel bundle is grappled to the mast.
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As the design basis fuel handling accident (described in the Clinton USAR, Section 15.7.4) occurs in the spent fuel building, any fuel handling accidents occurring in containment are bounded. The new mast is similar in design and function to the old mast and exceeds all design requirements.
Therefore, this new mest cannot create a new or different kind of accident. Since the overload cutoff and the ionded interlock still perform their design function there is no reduction in the margin of safety.
Consequently, the proposed change is acceptable.
The SURVERLANCE REQUIREMENTS of Technical Specification 4.7.4.e prescribes the sampling plans for snubber functional testing. Three possible plans are listed, which are statistically equivalent.
Plan 1 requires 10% for initial sample size and an additional 10% increase due to failures.
Plans 2 and 3 have an equivalent initial sample size; bnwever, the additional sample size is only one-half of the initial samp1s size.
The reduction in the additional sample size from 10% to 5% would make Plan 1 statistically consistent with Plans 2 and 3 cnd will ensure that each snubber is tested at least once every 15 years. Testing and evaluation of failed snubbers will still be accomplished as required by Technical Specifications 4.7.4.f, g, and h.
The reduction in additional sample size has been incorporated into the 1989 Edition of the ASME Boiler and Pressure Vessel Code,Section XI. Since the reduction in additional sample size will make the three sampling nians statistically equivalent, while still ensuring that all snubbers are tested at least eve y 15 years, the proposed change is acceptable.
3.0 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 Connission has previously issued a proposed finding that thi. amendment involves no significant hazardt consideration and there has been no public comment on such finding.
Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forthin10CFR51.22(c)(9).
Pursuantto10CFR51.22(b),noenvironmental impact statement or environmental assessment need be prepared in connection with the issuance of this amendment.
4.0, CONCLUSION The staff has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and rafety of the wi11 not be endangered by operation in the proposed manner, and (2) public 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.
Principal Contributor:
P. Brochman, R111/DRP Dated: August 3, 1990
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