ML20205P929

Requests That Rev to NRC 821029 SER for NUREG-0737,Item II.K.3.24,be Issued to Clarify Util Installed RCIC & HPCI HVAC Configuration,As Discovered During Preparation of DBDs for Sys

ML20205P929
Person / Time
Site:	Vermont Yankee
Issue date:	04/14/1999
From:	Sen G VERMONT YANKEE NUCLEAR POWER CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
RTR-NUREG-0737, RTR-NUREG-737, TASK-2.K.3.24, TASK-TM BVY-99-51, NUDOCS 9904210036
Download: ML20205P929 (2)

Text

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VERMONT YANKEE y NUCLEAR POWER CORPORATION ]

• j 185 Old Ferry Road, Brattleboro, VT 05301 7002 (802) 257-5271 April 14,1999 BVY 99-51 United States Nuclear Regulatory Commission ATTN: Document Control Desk Washington,DC 20555

References:

(a) Letter, USNRC to VYNPC,"NUREG-0737 ITEM ll.K.3.24, Adequacy of Space Cooling for HPCI and RCIC Syste,ms,"

NVY 82-180, dated October 29,1982.

(b) Letter, VYNPC to USNRC, " Vermont Yankee Response to NUREG-0737 Items due on January 1,1982," FVY 82-1, dated January 5,1982.

Subject:

Vermont Yankee Nuclear Power Station License No. DPR-28 (Docket No. 50-271)

Clarification to SER for NUREG-0737 Item II.K.3.24 NUREG-0737 Item II.K.3.24 states that the RCIC and HPCI systems should be designed to withstand a complete loss of offsite AC power to their suppon systems, including coolers, for at ,

least 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. l In Reference (a) Vermont Yankee received a Safety Evaluation Report (SER) confirming the adequacy of space cooling for our High Pressure Coolant Injection (HPCI) and Reactor Core Isolation Cooling (RCIC) systems.

l l During preparation of our Design Basis Documents (DBDs) for these systems, it was noted that the wording in the SER did not accurately characterize our facility configuration. Specifically,

the SER identifies "....the licensee has stated that the support systems and space coolers for the HPCI and RCIC systems all receive power from the same essential electrical buses as the equipment they serve which are powered by onsite sources. Therefore, contin'uous power would h

be available for the space coolers following a complete loss of offsite AC power. Since the HPCI and RCIC systems for Vermont Yankee, including their support systems and space coolers will not be affected by a loss of offsite power, we conclude that the requirements of TMI Task Action Plan ll.K.3.24 are satisfied."

The basis cited in the SER for approval was Reference (b), wherein we submitted our position with regard to the adequacy of space cooling for these systems by stating "We have completed our review of these systems at Vermont Yankee and have determined that, as presently designed, they can withstand a complete loss of off site alternating current power to their support systems, including coolers, for at least two hours."

Reference (b) does not contain specific wording describing the existence of space coolers and/or power supplies for space coolers. In fact, the RCIC and HPCI rooms at Vermont Yankee are not provided with space coolers. The RCIC and HPCI rooms are cooled by normal Reactor Building Heating Ventilation and Air Conditioning (HVAC) which would be lost during a postulated loss of offsite AC power. Our internal analysis with regard to this issue at the time acknowledged that 9904210036 990414 ADOCK 05000271 f

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VERMONT YANKEE NUCLEAR POWER CORPORATION

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the only source of room cooling to these areas was normal HVAC airflow to the rooms. The analysis determined however, that the existing design was sufTicient to support RCIC and HPCI operation for at least two hours without offsite AC power available.

As previously stated, this clarification was discovered during DBD development for these systems and is provided now as a clarification of our system configuration with regard to your SER (Reference a). We request that a revision to the SER be issued to clarify our installed RCIC and HPCI HVAC configuration to eliminate any confusion.

Should you have any questions concerning this matter, please contact Mr. Jeffrey T. Meyer at (802) 258-4105.

Sincerely, VERMONT YANKEE NUCLEAR POWER CORPORATION (1hMh '

OGthm Sen /

Licensing Manager cc: USNRC Region 1 Administrator USNRC Project Manager- VYNPS USNRC Resident Inspector-VYNPS Vermont Department of Public Service