ML20151X801

Special Rept:On 980622,groundwater Level at Piezometer P-22 Was Again Noted to Be Above Max Water Level by 0.71 Feet. Increased Frequency of Piezometer Monitoring & Installed Addl Piezometers at Toe of Slope Along Southwest Section

ML20151X801
Person / Time
Site:	North Anna
Issue date:	09/10/1998
From:	Matthews W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
98-383, NUDOCS 9809170257
Download: ML20151X801 (2)

Text

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a VIHOINIA ELucTHIC AND Powen COMPANY i

HIcIIMOND, VIRGINIA 20261 September 10,1998 United States Nuclear Regulatory Commission Serial No.98-383 Attention: Document Control Desk MPW Washington, D.C. 20555 Docket Nos. 50-338,339 License Nos. NPF-4,7 Gentlemen:

i VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 SERVICE WATER GROUND WATER SPECIAL REPORT

, North Anna Technical Specifications (TS) Section 6.9.2 requires a Special Report to be i submitted when groundwater levels specified for the service water reservoir have exceeded the current maximum water level. Since December 10,1996, a total of five

! Special Reports have been submitted to document piezometer P-22 exceeding the {

4 maximum water level. On June 22,1998, during the performance of TS surveillance l

tests the groundwater level at piezometer P-22 was again noted to be above the maximum water level by 0.71 feet.

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. Initial corrective actions identified the need to increase the frequency of piezometer monitoring and the installation of additional piezometers at the toe of the slope along l the southeast section to provide additional reference information. Monitoring was increased from semi-annually to monthly to confirm acceptable seerage conditions. To date, two standpipe piezometers, P-23 and P-24, have been instatied at the toe of the slope adjacent to piezometers P-21 and P-22. Measurements are currently scheduled for once a month until it is determined the water levels have stabilized, at which point measurements will revert to the frequency required by the station TS. The measurements taken for piezometer P-24, which is closest to P-22, is below the TS limit of 280 feet.

A change to the Updated Final Safety Analysis Report (UFSAR) has been approved for submittal to reflect the current configuration. A change to the station TS maximum water level requirement is also being pursued. Increased water level has been evaluated and does not indicate a significant reduction of the stability of the service water reservoir dike.

No new commitments are made as the result of this special report.

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9809170257 9'8dsIo PDR t *^ -

S ADOCK 05000338 pg.

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' The Station Nuclear Safety and Operating Committee has reviewed this report. Should you have any questions regarding this report, please contact us.

Very truly yours, l

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i DM% L W. R. Matthews Site Vice President l

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cc: U. S. Nuclear Regulatory Commission Region ll l Atlanta Federal Center 61 Forsyth St., SW, Guite 23T85 Atlanta, Georgia 30303 l

Mr. M. J. Morgan NRC Senior Resident inspector North Anna Power Station l l

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