ML20133H633
| ML20133H633 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 10/04/1985 |
| From: | Domer J TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8510180048 | |
| Download: ML20133H633 (4) | |
Text
--
1-TENNESSEE VALLEY AUTHORITY CH ATTANOOGA. TENNESSEE 37401 b gy,
400 Chestnut Street Tower II
'/ [
4 n: y October 4, 1985
{
~
g U.S. Nuclear Regulatory Commission Region II ATTN:
Dr. J. Nelson Grace, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
Dear Dr. Grace:
SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 - NRC-OIE REGION II INSPECTION REPORT 50-327/85-24 AND 50-328/85 SUPPLEMENTAL RESPONSE TO VIOLATION l'
Enclosed is our supplemental response to R. D. Walker's August 7,198#, letter to H. G. Parris transmitting IE Inspection Report Nos. 50-327/85-24 and 50-328/85-24 for our Sequoyah Nuclear Plant which cited TVA with two Soverity Level IV Violations.
As requested in R. D. Walker's September 25, 1985 letter to H. C. Parris, we are providing a specific explanation and documentation to support our position that the requirements of LCO 3.6.5.3 for intermediate deck doors were met during the period in question.
If you have any questions, please get in touch with R. E. Alsup at FTS 858-2725.
To the best of my knowledge, I declare the statements contained herein are complete and true.
Very truly yours, TENNESSEfVALLEYAUTHORITY
. /$dyrtul
. A. Domer, Chief Nuclear Licensing Enclosure cc:
Mr. James Taylor, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Conunission Washington, D.C.
20555 8510180048 851004 PDR ADOCK 05000327 PDR g
An Equ11 Opportunity Employer i
gg
i i
REVISED RESPONSE - NRC-01E INSPECTION REPORT NOS.
50-327/85-24 AND 50-328/85-24 R. D. WALKER'S LETTER TO H. G. PARRIS DATED AUGUST 7, 1985 Violation 50-328/85-24-03 Technical Specification 3.6.5.3 states that, the ice condenser inlet doors, intermediate deck doors, and top deck doors shall be closed and operable for modes 4 through 1.
Additionally, with one or more ice condenser doors inoperable, power operations may continue for up to 14 days provided the ice bed temperature is monitored once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and the maximum ice bed temperature is maintained less than or equal to 27 F.
Technical Specification 4.6.5.3.2 states, in part, that each intermediate deck door shall be verified closed and f ree of f rost accumulation by visual inspection at least once per 7 days.
Contrary to the above, on June 10, 1985, ice buildup was observed on the intermediate door and ice bed temperature was recorded once per eight hour shif t vice the required once per four hours due to a lack of adequate post maintenance criteria.
This is a Severity Level IV violation (Supplement 1).
1.
Admission or Denial of the A11 edged Violation TVA admits a violation occurred.
2.
Reason for the Violation The alleged violation states that the ice bed temperature must be recorded once per four hours if ice is observed on the intermediate deck doors.
Technical Specification 3.6.5.3 actually allows the ticxibility, in lieu of recording the ice bed temperature, to ".
. otherwise, restore the doors to their closed positions or OPERABLE status (as applicable) within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
On June 19,1985, at 0900 CST, a routine inspection of the unit 2 ice condenser revealed ice buildup on several intermediate deck doors. At 1331 CST on June 10, 1985, employees entered the unit 2 containment to remove the ice. This action was verified by reviewing the radiation work permits (RWP) and Administrative Instruction (A1)-8, " Access to Containment," data sheets which document names, dates, times, and purpose of containment entry. Verification of ice removal was documented by performance of Surveillance Instruction (SI)-3, " Daily, Weekly, and Ebnthly Logs," which was started at 1700 CST on June 10, 1985, and com-pleted on June 11, 1985, at 2015 CST.
SI-3 is the procedure used to fulfill the weekly Technical Specification Surveillance Requirement
~~
4.6.5.3.2.a which requires the intermediate deck doors be free of frost accumulation. The cited documentation provides positive assurance that the ice was removed and operability verified within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> allowed f
by Technical Specification 3.6.5.3.
The NRC inspection report stated that additional icing was observed on June 16, 1985, during containment entry to complete maintenance request (MR) A-553690. As a result of a review of the completed MR, RWPs, and AI-8 data sheets, it was discovered that this containment entry was actually made at 1024 CST on June 19, 1985. Through dis-cussion with the NRC resident inspector, it was verified that the June 16,1985 date referenced in the inspection report was in error.
The inspection report stated that this ice buildup was caused by inleakage of humid air through torn insulating tape on the overhead upper ice condenser doors. TVA has evaluated this condition and determined that the torn insulating tape does not constitute a signii-icant contribution to the buildup of ice.
Unit 2 has experienced a history of ice condenser inleakage, primarily through the existing vent blankets, which in conjunction with the high humidity, has resulted in additional ice accumulation. To address this problem, maintenance personnel established a routine of periodically entering the ice con-denser and removigg the ice buildup. This was in addition to perfor-cance of the weekly surveillance instruction required to meet Technical Specification Surveillance Requirement 4.6.5.3.2.a.
The periodic main-tenance routine was considered to be acceptable because the ice removal activity was the same as that performed for any ice buildup discovered during the weekly surveillance. A further review shows that RWPs and AI-8 data sheets document containment entry on June 19, 1985, to remove additional ice buildup.
Door operability was verified by performance of a pull test in accordance with SI-108, " Ice Condenser Doors," on the affected doors at 1600 CST on June 20, 1985.
SI-108 is the p ro-cedure used to comply with the 18-month Technical Specification Surveil-lance Requirement 4.6.5.3.2.b.
The cited documentation provides positive assurance that the doors were returned to operabic status within the 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> allowed by Technical Specification 3.6.5.3.
As locumented above, TVA couplied with all action requirementa for both events on June 10 and June 19, 1935.
During dis-cussion of these findings with the NRC resident ' inspector at Sequoyah
~
and the cognizant NRC Region II inspector, it was ascertained that the principal NRC concern resulted f rom performance of ice removal activities without formal procedures needed for work on safety-related equipment.
Af ter reevaluation of the periodic ice removal routine, TVA agrees that the potential for problems may exist due to the fact that this practice may not always be controlled by formal procedures.
3.
Corrective Steps Which Will Be Taken and the Results Achieved With respect to the two incidents of ice buildup found on June 10 and June 19, 1985, the only corrective step needed was the removal of the ice.
This was completed, and the intermediate deck doors returned to operable status within the 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> prescribed by technical specifi-cations.
N
s.
The cause of the increased containment humidity has been determined to be steam leakage through the steam generator manway. This problem is expected to be corrected during the current outage.
4.
Corrective Steps Which Have Been Taken to Avoid Further Violations To address the potential problems associated with periodic ice removal, TVA is preparing a Sequoyah Nuclear Plant surveillance instruction to provide specific instructions. These instructions will require that when ice or frost is discovered on the intermediate deck doors, Surveil-lance Requirement 4.6.5.3.2.b will be performed for those doors. This will determine the ef fect of the ice or f rost accumulation on door operability.
If the force required to lif t the subject door exceeds the values specified by 4.6.5.3.2.b, the door will be deemed inoperable, and Technical Specification actions of 3.6.5.3 will be met.
If the l
iced door passes the pull test, the door will be considered operable, and ice will be removed as work schedules allow. Af ter ice removal, the test will also be conducted to verify that the door has been returned to an operable condition.
5.
Date When Full Compliance Will Be Achieved Full compliance was achieved with removal of ice on June 10 and June 19, 1985, for each respective incident of ice buildup.
The surveillance instruction for periodic ice removal will be impicmented before entry into mode 4 following the current outage. A firm date for restart has not yet been established.
.