ML18153C568
| ML18153C568 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 03/14/1991 |
| From: | Saunders R, Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF ENFORCEMENT (OE) |
| References | |
| 91-087, 91-87, GL-89-13, NUDOCS 9103200186 | |
| Download: ML18153C568 (8) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 March 14, 1991 Director, Office of Enforcement United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 REPLY TO A NOTICE OF VIOLATION Serial No.
SPS/JWH Docket Nos.:
License Nos.:
NRG INSPECTION REPORT NOS. 50-280/90-36 & 50-281/90-36 91-087 RS 50-280 50-281 DPR-32 DPR-37.
We have reviewed your letter of February 12, 1991 in reference to the N RC inspection conducted October 28 to November 11, 1990 and reported in Inspection Report Nos.
50-280/90-36 and 50-281 /90-36. Our response to the Notice of Violation enclosed with your letter is provided in Attachment 1. Payment of the assessed civil penalty is enclosed as Attachment 2.
We have no objection to making this response a matter of public disclosure.
Should you have any questions, please contact us.
Very truly yours, i?I J~
D rr-v"* L. Stewart Attachments 1. Reply to a Notice of Violation
- 2. Voucher Check cc:
U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N. W.
Suite 2900 Atlanta, Georgia 30323 Mr. W. E. Holland
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NRG Senior Resident Inspector f\\ tc W.
1.... /-le( /c Surry Power Station I So, o c c. oo 9103200186 910?14 fDR ADOCK b56602eo Tt3:l 1f
- W PDR l i )"
COMMONWEAL TH OF VIRGINIA )
)
COUNTY OF HENRICO
)
The foregoing document was acknowledged before me, in and for the
- County and Commonwealth aforesaid, today by R. F. Saunders, who is Assistant Vice President - Nuclear Operations, for W. L. Stewart who is Senior Vice President - Nuclear, of Virginia Electric and Power Company.
He is duly authorized to execute and file the foregoing document in behalf of that Company, and the statements in the document are true to the best of his knowledge and belief.
Acknowledged before me this /Lf TJ' day of vdtt2A,cA, My Commission Expires:
L!/&"fj 3/
, 1921:...
, 199}__.
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Notary fki"ic (SEAL)
ATTACHMENT 1 REPLY TO A NOTICE OF VIOLATION NRC INSPECTION CONDUCTED OCTOBER 28, 1990 -
NOVEMBER 11, 1990 INSPECTION REPORT NOS. 50-280/90-36, 50-281 /90-36
REPLY TO A NOTICE OF VIOLATION NRC INSPECTION CONDUCTED OCTOBER 28, 1990 -
NOVEMBER 11, 1990 INSPECTION REPORT NOS. 50-280/90-36, 50-281 /90-36 NRC COMMENT "During an NRC inspection conducted on October 28 - December 15, 1990, a violation of NRC requirements was identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," 1 O CFR Part 2, Appendix C (1990), the Nuclear Regulatory Commission proposes to impose a civil penalty pursuant to Section 234 of the Atomic Energy Act of 1954, as amended (Act), 42 U.S.C. 2282, and 10 CFR 2.205. The particular violation and associated civil penalty are set forth below:
Technical Specification 3.4.A.2 requires that four Recirculation Spray Subsystems including coolers (heat exchangers) shall be operable whenever the unit's Reactor Coolant System temperature or pressure exceeds 350 degrees F. or 450 psig, respectively.
Technical Specification 3.0.1 requires that, in the event a Limiting Condition for Operation cannot be satisfied because of circumstances in excess of those addressed in the specification, the unit shall be placed in at least hot shutdown within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in at least cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
Contrary to the above, prior to October 6, 1990 for Unit 1 and October 23, 1990 for Unit 2, all of the Unit 1 and 2 Recirculation Spray Heat Exchangers (eight total) were inoperable for a period greater than 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> without the units being placed in hot shutdown.
This is a Severity Level Ill violation (Supplement I), Civil Penalty - $50,000" Page 1 of 4
REPLY TO A NOTICE OF VIOLATION NRC INSPECTION CONDUCTED OCTOBER 28. 1990 -
NOVEMBER 11. 1990 INSPECTION REPORT NOS. 50-280/90-36. 50-281 /90-36 1.
Admission or Denial of the Alleged Violation The violation is correct as stated.
- 2.
Reason for the Violation
- 3.
The direct cause of the violation was macroscopic fouling (macrofouling) of the Service Water (SW) side of the Recirculation Spray Heat Exchangers (RSHXs),
which resulted in SW flow being reduced to less than design flow.
The.
macrofouling was caused by debris, which was initially resident in the SW supply piping, being swept into the RSHXs by the high velocity inrush during SW flow initiation. The debris consisted primarily of hydroids which detached from the interior of the SW supply piping. In addition, some shellfish and small pieces of coal tar epoxy pipe coating were found in the debris.
The root cause of the macrofouling blockage was inadequate consideration of the consequences of marine growth in SW piping.
The previous focus was on microfouling and on macrofouling blockage issues related to transport of marine life into the SW system from the James River.
This SW piping had been inspected and cleaned during the 1988 and 1989 outages.
Therefore, the magnitude of in-plant marine growth which occurred and the degree to which it was dislodged by SW inrush were not previously anticipated or detected. This is in contrast to macrofouling experienced in other heat exchangers cooled by SW which was believed to be caused by transport from the river. The performance of the RSHXs was considered unlikely to be affected by either transport macrofouling because of the lower steady-state SW system flow rates and lower intake velocities which would exist during design basis accident conditions, or microfouling because the RSHXs are maintained in dry layup.
Corrective Steps Which Have Been Taken and the Results Achieved Based on the reduced SW flows observed during flow testing of the Unit 1 "B" and "C" RSHXs, the Unit 1 and Unit 2 RSHXs were declared inoperable at 0103 hours0.00119 days <br />0.0286 hours <br />1.703042e-4 weeks <br />3.91915e-5 months <br /> on October 23, 1990. Unit 2 was placed in hot shutdown at 061 O hours on October 23, 1990 and in cold shutdown at 0830 hours0.00961 days <br />0.231 hours <br />0.00137 weeks <br />3.15815e-4 months <br /> on October 24, 1990. Unit 1 was already in refueling shutdown when the RSHXs were declared inoperable.
The flow test results indicated that it was desirable to operate with the SW inlet piping to the RSHXs partially filled with water to reduce SW inrush velocity and turbulence. Following cleaning of the SW supply piping, additional flow testing of the Unit 1 "B" and "C" RSHXs was performed with the SW system initially in this partially filled configuration. The steady-state SW flow rates exceeded design requirements and no indication of significant macrofouling was present during the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> duration of the test. No undesirable hydraulic effects were observed.
Post-test inspection of the RSHXs revealed an insignificant amount of entrained debris. Based on the success of this test, the Unit 1 SW system was placed in this partial wet layup configuration prior to restart. Following cleaning, the Unit 2 SW Page 2 of 4
$ystem was placed in this partial wet layup configuration as well. The wet layup
. portions of the SW systems (downstream from the SW-MOV-103/203 valves to the top of the 36" header) are being chemically treated to provide both biological and pipewall corrosion control.
To reduce the potential for the return of hydroids, SW flow is being periodically alternated between the supply headers (which also provide cooling for the Bearing Cooling subsystem) thereby limiting the supply of oxygen and nutrients available for hydroid growth in the stagnant header.
- 4.
Corrective Steps That Will Be Taken to Avoid Further Violations An enhanced SW inspection and maintenance program is being implemented in response to Generic Letter 89-13. This program is intended to ensure that corrosion, erosion, protective coating failure, silting, and biofouling will not degrade the performance of safety-related. systems cooled by SW.
Initial.
- activities in accordance with our response to the Generic Letter were implemented for Unit 1 during the 1990 refueling outage and will be implemented for Unit 2 during the 1991 refueling outage. Inspection and cleaning activities will continue during future refueling outages.
During a meeting with NRC management on February 6, 1991, additional planned activities pursuant to Generic Letter 89-13 were presented in response to the RSHX macrofouling issue. These additional activities will be confirmed in a supplemental response to Generic Letter 89-13 which will be provided to the NRC in April, 1991. The following items specifically represent corrective steps to avoid further violations in the area of RSHX SW macrofouling:
Modifications to provide chemical treatment to control hydroid growth in the 48" SW headers to the RSHXs will be implemented. (Currently scheduled by March 31, 1991.)
SW monitoring and sampling programs will be initiated.
(Currently scheduled by March 31, 1991.)
The SW supply will be monitored for temperature, salinity, pH, conductivity; dissolved oxygen, chlorine, and ammonia and the results correlated with visual inspection results.
During the 1991 Unit 2 refueling outage, a flow test will be conducted on one Recirculation Spray SW subsystem to assess the effectiveness of the macrofouling control techniques. A post test inspection of the flow tested SW subsystem will be performed. An .as-found" inspection will also be performed on the other *Recirculation Spray SW subsystem. Similar testing and inspection will be performed again for Unit 1 during its 1992 refueling outage. A determination as to whether any further flow testing is required will then be made.
An ecosystem study has been initiated to support a long-term biological control strategy. This study will involve documentation search, temperature and salinity profiles for growth, flow testing, coupon testing, chlorine tolerance testing, and evaluation of the results from the SW monitoring program.
In addition to the Generic Letter 89-13 activities, a SW pipe repair and recoating project is also in progress. This project involves cleaning, repair of corrosion Page 3 of 4
damage, and recoating with a more durable material. Portions of the Unit 1 RSHX SW supply piping were recoated during the 1990 refueling outage.
Recoating of the Unit 2 RSHX SW supply piping will commence during the 1991 refueling outage.
The activities commited to as part of our response to Generic Letter 89-13 are adequate to prevent recurrence of any significant RSHX macrofouling. In a letter dated February 20, 1991, the NRC concurred that. the testing and inspection outlined in the February 6, 1991, management meeting were "sufficient to warrant continued operation of both units."
- s.
The Date When Full compliance Was Achieved Full compliance was achieved for Unit 2 on November 11, 1990, when Reactor Coolant System temperature was increased to above 350 degrees Fahrenheit with the RSHXs restored to operable status.
Full compliance was simila,rly achieved for Unit 1 on December 15, 1990.
Continued compliance will be assured by implementation of the modifications and enhanced Generic Letter 89-13 SW inspection and maintenance program described herein.
Page 4 of 4
ATTACHMENT 2 VOUCHER CHECK