ML19345A256
| ML19345A256 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 10/14/1980 |
| From: | Rich Smith VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| WVY-80-146, NUDOCS 8010210336 | |
| Download: ML19345A256 (2) | |
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i.) VERMONT Y AS KEE NUCLEAR POWER CORPOR ATION
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SEVENTY SEVEN GROVE STREET B.3.2.1 WY 80-146 RUTLAND VERF10NT 05701 REPLY TO.
ENGINEERING OFFICE TURNPlKE Ro AD WESTBoRo. M ASS ACHUSETTS 01581 TELEPHONE 61)-366 9011 October 14, 1980 United States Nuclear Regulatory Commission Washington, DC 20555 Attention: Office of Nuclear Reactor Regulation
References:
(a) License No. DPR-28 (Docket No. 50-271)
(b) Letter D. G. Eisenhut to All Operating Boiling Water Reactors, dated July 7,1980
Subject:
Response to NRC Request for Scram Discharge Volume Technical Specification Changes
Dear Sir:
Reference (b) requested that Vermont Yankee amend the station Technical Specifications with respect to control rod drive scram discharge volume (SDV) capability. Guidance was given in the form of model standardized technical specifications (STS) which provided increased surveillance requirements for SDV vent and drain valves and LC0/ surveillance requirements for RPS and Control Rod Block SDIV limit switches. Vermont Yankee has reviewed the proposed amendment with respect to our facility and our current technical specifications. Our positions on the NRC proposals are listed below.
1)
Operability of SDV Vent and Drain Valves Would require the subject valves to be tested and timed:
Model STS a) after every shutdown of greater than 120 days b) every 120 days during normal operation Model STS would also require that the SDV vent and drain valves be verified open at least once per 31 days.
Vermont Yankee The subject valves at Vermont Yankee are tested and timed in accordance with the Vermont Yankee Inservice Position Inspection Program.
The program requires that this testing be done quarterly and is therefore more conservative than the change proposed by the NRC.
Vermont Yankee agrees with the position that the vent and drain valves be verified open at least once per month. This requirement will be administratively enforced until such time as this minor change can be included in another proposed change submittal.
8010210 3 3f
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October 14, 1980 U.S. Nuclstr Rigulatory Commissian Abtn:. Office of Nuclsar Rcnetor Regulation Page 2 2)
Surveillance Requirements for SDIV High Water Level Scram Model STS Would require:
a) channel functional test every 31 days b) channel calibration every 18 months 1
Current Technical Specification requires
-Vermont. Yankee a) channel functional test every 3 monthr; Position b) channel calibration every refueling (12 months)
Vermont Yankee believes that the testing interval for this trip should not be reduced for the following reasons:
- 1) Calibration is done concurrent with the functional
. test on a quarterly basis.
Past functional testing of this trip has been highly successful with no instances of failed SDIV level switches due in any part to float assembly misoperation.
- 2) Tripling the frequency of functional testing in this area would unnecessarily increase personnel exposure.
Technical Specification Requirement for Control Rod Block on SDIV High 3)
Water Level Scram Bypass Contains requirement for this rod block function to be Model STS operable when the mode switch is in Run, Startup/ Hot Standby, or Shutdown or Refuel.
Associated testing and calibration requirements are also provided.
Vermont Yankee does not feel that this requirement is Vermont Yankee j
justified for the following reasons:
Position
- 1) Plant design at Vermont Yankee does not allow the J ~
SDIV high water level scram to be bypassed unless the mode switch is in the shutdown or refuel position.
l In these modes, a low power. rod block is concurrently provided by the IRM system as well as by the high level scram bypass switch.
- 2) At Vermont Yankee the SDIV rod block can only be reset by' draining the SDIV to a point below the 12
' gallon control rod block setpoint. This assures that during the period of time that the SDIV high water level trip is bypassed to allow draining of the SDIV a rod block is present until the water level drops below the rod block setpoint.
We trust the information presented above is satisfactory; however, should you'have any questions, please feel free to contact us.
Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION g4s R. L. Smit Licensing Engineer
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