ML17345B317
| ML17345B317 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 10/14/1983 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17345B316 | List: |
| References | |
| NUDOCS 8310270161 | |
| Download: ML17345B317 (7) | |
Text
a+s <<co>C~
0
~
~~ c
'(
I 0
t7 4~*~4 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, O. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT-NO=;96--TO-FACILITY.=OPERATING LICENSE NO.
DPR-31 AND AMENDMENT NO.
90 TO FACILITY OPERATING LICENSE NO.
DPR-41 FL'ORIDA OWER AND 'L'.IGHT COMPANY TURKEY POINT PLANT UNIT NOS.
3 AND 4 DOCKET NOS. 50-250 AND 50-351 Introduction To reflect accumulated experience obtained from operating plants in the past several years the NRC revised the Standard Technical Specifications on the surveillance requirements for safety-related snubbers.
On November 20, 1980, this document was transmitted to operating plants excluding those under SEP along with a request for submittal of appropriate license amendments to incorporate the requirements of this revision within 120 days.
The same request was extended to SEP plants on March 23; 1981.
Florida Power and Light Company letter L-83-454, dated August 19,
- 1983, submitted proposed amendments to the Turkey Point Units 3 and 4 Facility Technical Specifications.
The proposal consists of changes to the Inservice Surveillance Requirements for safety-related snubbers.
These amendments consolidate all previous submittals (L-81-206, dated May 14, 1981 and L-82-244, dated June 10, 1982) regarding safety-related snubbers.
Discussion Numerous discoveries of inoperative snubbers in the period of 1973 to 1975 resulted in their surveillance requirements in the Technical Specifi-cations for operating reactor plants.
However, several deficiencies were identified after the original requirements were in force for several years.
These deficiencies are:
1.
Mechanical snubbers were not included in these-requirements.
2.
The rated capacity of snubbers was used as a limit to the inservice test requirement.
3.
NRC approval was necessary for the acceptance of seal materials.
4.
Inservice test requirements were not clearly defined.
ss>os7oqqz sszo<s ',',;
Q~
PDR* "."'<'".
PDR ADOCK 05000250 J
~ All>>
W
~
+W' 1I
5.
In-place inservice testing was not permitted.
Since mechanical snubbers were not subject to any surveillance require-
- ,.ants, some icensees and permit holders beIieved that mechanical snubbers were preferred by NRC.
Many plants used mechanical snubbers a~ o>>gina]
Gqu,"it<et'it c" ~. !ita!'!y. Qthes rc""osted
.= replace the.ir iiydraulic. snubbers.
with mechanical ones to simplify or avoid a inservice surveillance an unsurv program.
This is directly contradictory to NRC's intent' f
eyed mechanical
- snubber, the most likely failure is permanent,.
lock-up.
This failure mode can be hhrmfuI to the system during normal plant operations.
During the period of 1973-1975, when the first hydraulic snubber surveillance requirements in the Technical Specifications were drafted, a compromise was made to limit the testing of snubbers to those with rated capacity of not more than 50,000 lbs.
This is because of the available capacity of ttfe test equipment and the requirement to test some parameters at the snubber rated load.
Since then, greater equip-ment capacity and'etter understanding of parametric correlation both developed.
To maintain this arbitrary 50,000 lb. limit could mean an unnecessary compromise. on pl.ant safety.
The original hydraulic snubber problem started from leaking seals.
Most seal materials of the 1973 vintage could not withstand the temperature and irradiation environments.
Ethylene propylene was the first material that could offer a reasonable service life for those seals.
In order to discourage the use of unproven'material for those seals, the words "NRC approved material" were used in the Techni.cal Specifications.
Staff members were asked to approve different seal materials on many occasions.
Con'sequently, since the basis for the approval was not defined, the. development of better seal materials by the industry was actually discouraged.
The not-weII-defined acceptance criteria in the earlier version of the t~sting requirements resulted in non-uniform interpretations and implementation.
Acceptance Criteria were set individually at widely different ranges.
Since the rationale of adopting a specific acceptance criteria was not clear, I&E inspectors found it'smpossible to make any necessary corrections.
In some cases, snubbers were tested wi.hout re=erence
'.o acceptance criteria.
Testing of snubbers was usually accomplished by removing snubbers from their installed positions, mounting them on a testing rig, conducting the test, removing them from rig, and reinstalling them to the working position.
Many snubbel.s were damaoed in the removing and reinstallation process.
This defeated the purpose for conducting tests.
Since methods and equipment have been developed to r.ondurt jn-nlace tes+~
on sn"bh.-.rs ta~"'..-.g 'advan':~ge of th&88'evelopments could result in minimizing the damage to snubbers caused by removal a~d reinstallation plus time.,and cost savings to the plants.
From these short-comings it was concluded that the snubber surveillance requirements for the Technical Specificatjons should be revised.
Evaluation The revised surveillance requirements correct these deficiencies in the following manner:
1.
Mechanical snubbers are now inc1uded in the surveillance program.
.P..
No arbitrary snubber capacity is used as a limit to the inservice test requirement.
3.
Seal material no longer requires NRC approval.
A monitoring program shall be implemented to assure that snubbers are functioning within thei r service life.
I 4
4.
Clearly defined inservice test requirements for snubbers shall be implemented:
5.
In-place inservice testing shall be permitted.
The proposed amendmentSto Turkey Point Units 3 and 4 Technical Speci
- cations
'surveillance requirements are in general agreement with the Inservice Surveil-lance Requirements for snubbers as stated in the Standard Technical Specifica-tions with certain exceptions which are as follows:
a.
All surveillance requirements relating only to hydraulic snubbers have been deleted since hydraulic snubbers have been replaced with mechanical snubbers in both Turkey Point Units 3 and 4.
b.
STS Sections 4.7.9.b - The Standard Technical Specifications require that visual inspection shall verify, in those locations where snubbers movement can be manually induced without disconnecting the snubber, that the snubber has freedom of movement and is not frozen up.
This requirement has been deleted from the Turkey Point Technical Specifi-cations since the mechanical snubbers installed cannot be manually moved without disconnecting the snubbers from the pins.
C.
STS Section 4.7.9.c - The Standard Technical Specifications require that if.
any snubber selected for functional testing either fails to lockup or fails to move, i.e., frozen in place, the cause will be evaluated and if caused by manufacturer or design deficiency all snubbers of the same design subject to the. same defect shall, be functional 1>> teste>
The licensee has subs". ted the following in place of the above:
"Should the results of the evaluation indicate that the failure wa."caused by manufacturer or design deficiency, further action shall be taken if needed, based on manufacturer or engineering recommendations".
d.
STS Section 4.7.9.d - the Standard Technical Specifications require that for snubbers specifically required to not displace under continuous load, the ability of the snubber to withstand load without displacement shall be verified.
The licensee has deleted this requirement since "snubbers specifically required to not displace" are not used in Turkey Point Units 3 and 4.
~Summa r Based on our review and the details identified above we find the proposed amendments to Turkey Point Units 3 and 4 Technical Specifications address the safety concerns and are in conformance with the Standard Technical Specifications and are, therefore, acceptable.
'nvi ronmental Consideration Me have determined that the amendmen.s do not authorize a change in effluent types or total amounts nor an increase in power level and wit 1 not result in any significant envir oanental impact.
Having made this determination, we have further concluded that the, amendments involve an action which is insignificant fran the standpoint of envirormental impact and, pursuant to 10 CFR gl.5(d)(4), that an environmental impact statement or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of these amendments.
Conclusion Me have 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 (2) such activities'ill be conducted in compliance with tne Commission's regulations and the issuance of the amendments will not be inimical to the common defense and security or to the hea'Ith and safety of the publ.ic.
Date:
October 14, 1983
C