ML18052B390
| ML18052B390 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 11/25/1987 |
| From: | Berry K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| Shared Package | |
| ML18052B391 | List: |
| References | |
| TAC-M54555, NUDOCS 8711300134 | |
| Download: ML18052B390 (5) | |
Text
consumers Power l'OWERINli MIC.lllliAN'S l'ROliRESS General Offices:
1945 West Parnell Road, Jackson, Ml 49201 * (517) 788-1636 November 25, 1987 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -
TECHNICAL SPECIFICATIONS CHANGE REQUEST REVISION -
CORE EXIT THERMOCOUPLES (TAC NO M54555)
Kenneth W Berry Director Nuclear licensing By letter of November 21, 1985 Consumers Power Company submitted a proposed change to the Palisades Technical Specifications providing operability and surveillance requirements for the qualified core exit thermocouples (CETs).
Subsequent to the submittal we incorporated the proposed Technical Specifications into our administrative procedures which required the proposed changes be met.
We have since determined that the proposed calibration requirements are overly restrictive and are therefore proposing to modify them to be consistent with the incore calibration tequirements.
The core exit thermocouples calibration frequency was proposed as 18 months which we now propose to change to each refueling cycle.
The incores are calibrated per Technical Specification 4.18.1.1 on a refueling cycle basis.
Since the CETs are contained within the same assembly as the incores the CETs are calibrated at the same time. If the refueling cycle were to exceed 18 months, as it presently has, an added radiation dose of about 800 millirem results from performing the calibration separately.
The CETs are not subject to instrument drift since their output is based on a voltage signal generated from two dissimilar metals.
Instead, their typical failure mode is to an open circuit which is easily detectable during the monthly channel check.
OC1187-0206-NL02-NL04
Nuclear Regulatory Commission Palisades Plant TSCR Revision - Core Exit Thermocouples November 25, 1987 2
A check for $150.00 accompanied our previous November 21, 1985 submittal.
We request the amendment to be effective upon issuance.
This proposed change supersedes in its entirety the change request of November 21, 1985.
Revisions are identified in the right hand column in the attachments.
Kenneth W Berry Director, Nuclear Licensing CC Administrator, Region III, NRC NRC Resident Inspector - Palisades Attachment OC1187-0206-NL02-NL04
1 CONSUMERS POWER COMPANY Docket 50-255
____ _:._~-
Request for Change to the Technical Specifications License DPR-20 For the reasons hereinafter set forth, it is requested that the Technical Specifications contained in the Provisional Operating License DPR-20, Docket 50-255, issued to Consumers Power Company on October 16, 1972, fo~ the Palisades Plant be changed as described in Section I below:
I.
Changes
- 1.
- 2.
Add a new item to Table 3.17.4 and add footnote (i) as follows:
No 22 Function Unit Core Exit Thermocouples Minimum Operable Channels 2/Core Quadrant (i)
Minimum Degree of Redundancy l/Core Quadrant Permissible Bypass Conditions Not Required in cold or Refueling Shutdown (i)
The core exit thermocouples in core quadrant locations (H2, G7, J7, JlO), (Q4, R7, RB, Nll), (Ml3, Xl4, Ql6, Rl7) and (Bl3, Hl3, Jl6, Gl7) are to be used in determining the minimum operable equipment.
Add a new item to Table 4.1.3 and add footnote (6) as follows:
No Channel Description Function Frequency Surv Method 23 a) Check a) Comparison I
I I
Core Exit Thermocouples(6) b) Calibrate M
(6) of channels I b) Known voltage sub""."
stituted for thermocouple (6)
Only applicable to core exit thermocouples in core locations H2, G7, J7, JlO, Q4, R7, RB, Nll, Ml3, Xl4, Ql6, Rl7, Bl3, Hl3, Jl6 and Gl7.
These thermocouples will be calibrated on a I
refueling cycle frequency.
I
- 3.
Add new paragraph to 3.17 Basis as shown on page 3-77 of page changes.
II. Discussion The above proposed Technical Specifications changes result from Generic Letter B2-2B which required licensees to submit their plans for OC11B7-0206-NL02-NL04 I
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2 installing instrumentation for the detection of inadequate core cooling.
Palisades has upgraded the range of the subcooling margin monitor, upgraded the qualification and will upgrade the readout capability of the core exit thermocouples and is providing a reactor vessel level monitoring system.
Generic Letter 83-37 provided requirements for Technical Specifications for NUREG-0737 items, including instrumentation for detection of inadequate core cooling.
These proposed changes to the Technical Specifications incorporate the required changes to the core exit thermocouples portion of core cooling instrumentation.
The proposed operational requirements are more restrictive than the Standard Technical Specifications (STS) provided in Generic Letter 83-37.
Section 3.17.2 of the Palisades Technical Specifications requires the reactor be placed in a hot shutdown condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> if the number of channels falls below the "minimum operable channels."
The STS however would allow the plant to remain in power operation for 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> with less than the minimum channels operable or be in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
The proposed calibration frequency of each refueling cycle versus I
18 months as specified in the Standard Technical Specifications is I
requested to be consistent in the incore calibration frequency of each I
refueling cycle in Specification 4.18.1.1.
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are calibrated when the incore calibration is done.
If the surveillance I
frequency is not consistent additional calibrations of the CETs may be I
required to meet the Technical Specifications.
The resulting added I
radiation exposure to workers conducting the calibration is estimated to I
be ab(;>Ut 800 millirem.
Since the CETs are not subject to.instrument
/
drift, as their output is based on a voltage signal generated from two
/
dissimilar metals, the change of calibration frequency will not affect I
performance.
The typical failure mode is an open circuit which is easily I
detectable during the monthly checks.
Also, most refueling cycles will I
not exceed an 18 month interval so the change will typically not involve
/
an actual change in calibration frequency in these cases.
I Analysis of No Significant Hazards Consideration Upgrading of the core exit thermocouples was completed during the I
1985-86 refueling outage.
Presently no Technical Specification for the I
CETs exist.
These proposed changes provide operational requirements I
that are more restrictive than the Standard Technical Specifications I
while the surveillance frequency has been changes from 18 months to each
)
refueling cycle.
The upgrading of the CETs to provide environmentally I
qualified thermocouples and increasing the range of the control room
/
temperature indicator will increase the operators ability to monitor I_
core temperatures following an accident.
The addition of these I
specifications will provide operability and surveillance requirements I
that do not increase the probability or consequences on an accident or I
malfunction of equipment important to safety that has been previously I
evaluated in the FSAR.
OC1187-0206-NL02-NL04
3 The addition of these specifications also do not create the possibility of a new or different type of accident or malfunction than has been previously evaluated.
The environmentally qualified CETs increased range of the temperature indication provide the operator with better monitoring capability.
The Technical Specification require the equipment be operable, calibration will be done in cold shutdown, and no different type of accident or malfunction will be created.
Finally, there is no reduction in the margin of safety produced by the incorporation of these environmentally qualified CETs and wider range temperature indication into the plant and adoption of these proposed Technical Specifications.
The proposed operational requirements are more restrictive than the Standard Technical Specifications.
Although the calibration requirements are different than the Standard Technical Specifications they will normally fall within the same time as a typical refueling cycle will be about an 18 month period.
Since the failure mode is to an open circuit and not through instrument drift the monthly channel check.will verify CET operability.
Calibration on a schedule consistent with incore calibration will also result in less radiation exposure if the 18-month surveillance frequency would require more frequent calibration.
- III. Conclusion The Palisades Plant Review Committee has *reviewed this Technical Specification Change Request.and has determined that this change does not involve an unreviewed safety question and therefore involves no significant hazards consideration.
This change has also been reviewed under the cognizance of the Nuclear Safety Board.
A copy of this Technical Specification Change Request has been sent to the State of Michigan official designated to receive such Amendments to the Operating License.
CONSUMERS POWER COMPANY By~~~~~~-:=:::-:-;--
F Buckman, Vice Pre ent Nuclear Operations Sworn and subscribed to before me this 25th day of November 1987.
Elaine E Buehr4r, Notary Public Jackson County, Michigan My commission expires October 31, 1989 OC1187-0206-NL02-NL04 I
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