ML20247H094
| ML20247H094 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 05/14/1998 |
| From: | Leach D VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Lieberman J NRC OFFICE OF ENFORCEMENT (OE) |
| References | |
| 50-271-97-10, BVY-98-73, NUDOCS 9805210062 | |
| Download: ML20247H094 (20) | |
Text
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VERMONT YANKEE
.- p NUCLEAR POWER CORPORATION 185 Old Ferry Road, Brattleboro, VT 05301 7002 (802) 257-5271 May 14,1998 BVY 98-73 J. Lieberman Director, Office of Enforcement U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Rockville, MD 20852 2738
References:
(a)
Letter, USNRC to VYNPC, Notice of Violation and Proposed imposition of C;vil Penalty, NVY 98-53, dated April 14,1998 (b)
Predecisional Enforcement Conference on March 2,1998 (c)
Letter, VYNPC to USNRC, Reply to inspection Report 97-201, VY Design Inspection, BVY 97-138, dated October 27,1997
Subject:
Vermont Yankee Nuclear Power Station License No. DPR-28 (Docket No. 50-271)
Reply to a Notice of Violation - Inspection Report No. 50-271/97-10 This letter is written in response to Reference (a), which documents the findings of an inspection conducted between September 29 and November 20, 1997. The inspection identified several violations.
The violations revealed two major areas needing improvement: timeliness of corrective action and general process improvement. The timeliness issue is being addressed via a multi-pronged approach that melds human performance improvement initiatives with management expectations and oversight. We believe our recent trends in commitment management and closure coupled with the performance improvement efforts, being led by a senior plant manager, demonstrate that these efforts are having a positive effect. The process improvement issue is being addressed by both a Company-wide Continuous Process Improvement effort, for which virtually all managers and supervisors have received training, and a formal, extensive Configuration Management Improvement Program (CMIP). It should be noted that the CMIP is a rigorous effort spanning 3 years.
Our Design Basis Document (DBD) program was initiated before.the A/E inspection. This program is delivering design basis information to our engineering organization in a carefully prioritized manner while working in concert with the validation effort which utilizes an SSFl type review. Both DBD development and validation have been effectively revealing and j
documenting many design issues with a low threshold for response. These programs are a multi-year effort with a scheduled completion date of December,1999 for the initial effort.
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Our responses to the individual violations are provided below.
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VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98 73 / Page 2 1.
VIOLATIONS ASSOCIATED WITH TORUS TEMPERATURE A.
10 CFR Part 50, Appendix B., Criterion til, Design Control, requires, in part, that l
measures shall be established to assure that applicable regulatory requirements and the design basis, as defined in 50.2 and as specified in the license application, for structures, systems, and components, are correctly translated into specifications, drawings, procedures and instructions and that measures shall be established for the identification and control of design interfaces and for coordination among participating design organizations.
Contrary to the above, in 1982, the licensee failed to control the design interfaces and failed to assure that the design basis for the maximum torus temperature normal operating limit was correctly translated into specifications. Specifically, the analyses to support a 1982 Technical Specification (TS) license amendment request (to increase the normal torus water temperature limit from 90 F to 100 F) did not consider the impact of this change on design basis analyses such as the emergency core cooling system (ECCS) pump net positive suction head (NPSH) margin calculations, loss of coolant accident (LOCA) containment analyses, ECCS piping stress and support load calculations, and equipment qualification. An initial torus temperature of 90*F was assumed in these analyses. (01013) (This violation occurred beyond the five year statute of limitations period for assessing civil penalties; therefore, this violation was not considered for purposes of determining any civil penalty)
(1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation This violation resulted from weaknesses in Vermont Yankee's (VY) configuration management process during the time period when this TS change was submitted. This was apparent by the narrow focus of the submittal and the lack of appropriate interdepartmental reviews of the technical justification supporting the change.
(3)
Corrective Steps Taken and the Results Achieved Conservative administrative controls were implemented to preclude unlimited operation at elevated suppression pool initial temperatures. Administrative limits will remain in place until the TS are revised.
Current analysis supports a return to the original design basis parameters for initial suppession pool temperature. A TS proposed change was submitted on May 8,1998 to revise the maximum normal suppression pool temperature to 90 F.
(4)
Corrective Steps That Will be Taken to Avoid Further Violations The TS change process has improved since this 1982 change. Improvements in the review processes for TS changes would be more likely to prevent a similar occurrence
VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98-73 / Page 3 today. In addition, improvements in the breadth and depth of our Licer. sing Department review of all submittats to the NRC have introduced additional opportunities to identify problems similar to that which occurred in 1982. Similar improvements have occurred
'in design engineering and FSAR procedures.
Additionally, in February 1997, Vermont Yankee (VY) initiated a Configuration i
Management improvement Program (CMIP) to improve our design and configuration control processes. One product of our CMIP effort was the development and issuance of our " Document Change Request" procedure on March 31,1998. This procedure provides the requirements and instructions for controlling changes in plant design that do not result in a physical modification to the plant, such as the subject of this violation.
L This procedure ensures that appropriate multi-disciplined reviews are completed as necessary for non-physical design changes. Additional improvements are planned to more clearly identify how and where Technical Specification setpoints are used in engineering calculations.
l (5)
Date When Full Comofiance Will be Achieved Interim compliance is achieved through our implementation of a conservative administrative limit on the maximum normal suppression pool water temperature. Final resolution of this issue will occur when we receive approval for a revised TS limit for this parameter.
B.
10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action, requires, in part, that measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected. In the case of significant conditions adverse to quality, the measures shall assure that the cause of the condition is determiN und'Eorrective action taken to preclude repetition. The identification of the significant condition adverse to quality, the cause of the condition, and the corrective action taken shall be documented and reported to appropriate levels of management.
Contrary to the above, between May 1994,' and November 20,1997, the licensee failed to properly evaluate and correct,in a timely manner, an identified condition adverse to quality involving the discrepancy between the design basis and the TS limit for maximum normal torus temperature (described in Section 1.A). Specifically, in May 1994, the licensee identified that the TS limit of 100'F for maximum torus normal
. operating temperature (in place as of June 6,1985, when TS Amendment 88 was issued) was not consistent with assumptions made in the Final Safety Analysis Report l
(FSAR) description of LOCA containment response, and did not properly evaluate and correct this condition adverse to quality in a timely manner. Specifically:
j The analyses to support a safety evaluation pursuant to 10 CFR 50.59 were not initiated until November 1995.
The safety evaluation and operability f-determination were not completed until April 8,1996.
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' VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98-73 / Page 4 The nonconformance betwaen the FSAR and the TS was not entered into the licensee's corrective action process until November 2,1995.
Administrative controls to limit normal torus temperature to 90'F, consistent with the design basis, were not established until December 1,1995.
The residual heat removal (RHR) system operating procedure was not revised to reflect the 90 F administrative limit until April 1997.
On March 26, 1996, the licensee initiated an internal event report that questioned the ability to technically Justify plant operation with a torus temperature in excess of 90 F because of concerns associated with the core decay heat model, as well as the need to consider energy introduction into the containment from continued injection of feedwater. Within one hour, the licensee reported the condition to the NRC as potential operation outside of the design basis pursuant to 10 CFR 50.72 however, the licensee only reviewed two years of plant operating logs to determine if torus temperature had actually exceeded 90*F. Since no instances were identified, the licensee incorrectly concluded that the condition was not reportable as a LER, pursuant to 10 CFR 50.73. A comprehensive review of plant operating logs was not performed until May 29,1997.
Although the assessment of the concerns identified in March 1996, determined that maximum torus temperature, as a result of a LOCA, was acceptable only if an initial torus temperature of 90 F was assumed, the licensee had not requested j
a TS change as of November 20,1997. (01023)
(1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation The cause of this violation was a lack of focus on a very complex issue due to a non-integrated corrective action process. This issue pre-dates our Event Report process which was initiated to consolidate our previous multiple corrective action processes and i
provide better tools to investigate and prioritize issues.
I (3)
Corrective Steos Taken and the Results Achieved A self assessment of the timeliness of the suppression pool temperature problem was performed in late 1997. Resulting from this assessment were recommendations to l
establish improved performance indicators for Basis for Maintaining Operation (BMO) tracking and timeliness. Also recommended were continued efforts to refine the BMO process.
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VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98-73 / Page 5 The Event Report (ER) process is our consolidated corrective action program that l
presents such issues to the daily plant meeting for screening. This ensures a multi-l disciplined initial assessment for priority of these issues and appropriate assignment of investigations. This process was not in place at the time of this initial event.
Additionally, we have revised the ER process to simplify and incorporate reduced completion times for event investigations and enhanced operability determinations using our BMO process. The status of outstanding ERs, commitments and BMOs are periodically reviewed by management and our independent review committees.
l Our significant ER backlog for the years 1996 and 1997 has been previously recognized and ER backlog reduction was incorporated into our 1997 company goals. The existing ER backlog was significantly reduced by the end of 1997.
We have also recognized a weakness in our Licensing function and have increased staffing in this area and established a dedicated manager for this group.
(4)
Corrective Steos That Will be Taken to Avoid Further Violations l
In addition to continuing our ER backlog reduction efforts, we have also incorporated a 1998 company goal to reduce the percentage of open, higher level commitment items and ER branch commitments greater than one year old. The purpose of this company goal is to focus management attention and resources on the corrective action backlog and keep it within acceptable limits.
Additionally, the Engineering Organization is currently improving their management of work and open corrective action issues. These improvements in work management are expected be in place by July,1998.
(5)
Date When Full Compliance Will be Achieved The discussion above highlights significant improvements and monitoring of our corrective action process. Further, we are continually striving to improve these processes and their timeliness through lessons learned from events, inspections, audits, self assessments and benchmarking other utilities. As a result of our initiatives, our prioritization, trending and timeliness of response to significant issues is improving.
Therefore, we believe our corrective action process is currently in compliance with requirements.
C.
10 CFR 50.73(a)(2) requires, in part, that licensees shall submit a Licensee Event Report (LER) within L days after the discovery of the event, for any event or condition that resulted in the nuclear power plant being in a condition that was outside the design basis of the plant.
Contrary to the above, between June 28 and November 20,1997, the licensee failed to report a condition that resulted in operation outside the design basis of the plant.
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y VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98 73 / Page 6 Specifically, on May 29,1997, the licensee discovered that the plant had operated with torus temperature above 90*F for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in two instances between 1985 and 1995 (a two-day period in August 1988, and an eight day period in 1993);
h however, as of November 20,1997, the licensee had not reported the condition to the NRC, a period in excess of 30 days. This condition was outside of the design basis of
' the plant in that an initial torus temperature of 90"F was used in design basis analyses j-
- for ECCS pump NPSH margin calculations, LOCA containment _ response, ECCS piping L
stress and support load calculations, and equipment qualification.. Additionally, when -
continued feedwater injection was considered in the LOCA containment analysis, the.
peak torus water temperature was acceptable only if an initial torus temperature of 90'F L
. was assumed. (01033)
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- These violations in the aggregate constitute a Severity Level 111 problem - Civil Penalty l
-$55,000.
. (1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation The VY deportability procedure lacked adequate guidance for application of " engineering judgement" and other terminology necessary for compliance with NUREG 1022 in determining deportability.
(3)'
Corrective Steos Taken and the Results Achieved Vermont Yankee submitted LER 97-20 on November 26,1997 for the suppression pool temperature issue and has subsequently submitted - two supplements, as new information became available.
' Our procedure governing deportability has been revised to include interim' guidance to require deportability decisions to consider the need for added conservatism, especially relating to issues of a complex nature.
(4);
Corrective Steos That Will be Taken to Avoid Further Violations Vermont Yankee has initiated a benchmarking effort to improve our reporting process.
-This effort includes interviews with Licensing and Regulatory Compliance personnel l.
representing numerous BWR plants of comparable vintage. To date, licensing personnel representing 8 operating units have been interviewed to determine the processes, thresholds, and industry guidance considered appropriate when evaluating conditions for deportability requirements subject to 10CFR50.73. The benchmarking survey is expected to be completed by June,1998. The survey results will be assessed in light of BWR Owners Grc,up initiatives and rulemaking efforts by the Commission. The lessons learned from these activities will be factored into our deportability process.
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VERMONT. YANKEE NUCLEAR POWER CORPORATION l
BVY 98-73 / Page 7 l
15)
'Date When Full Comoliance Will be Achieved 1
l Full compliance was achieved on November 26,1997 when LER 97-20 was submittad.
II.
VIOLATIONS NOT ASSESSED A civil PENALTY A.
10 CFR Part 50, Appendix B, Criterion 111, Design Control, requires, in part, that j
measures shall be established to assure that applicable regulatory requirements and the i
design basis, as defined in 50.2 and as specified in the license application, for i
structures, systems, and components, are correctly translated into specifications, drawings, procedures and instructions and that measures shall be established for the selection and review of materials, parts, equipment, and processes that are essential to the safety-related functions of the structures, systems and components. Criterion ill l-also requires that measures shall be established for the identification and control of l
design interfaces and for coordination among participating design organizations and that design control measures shall provide for verifying or checking the adequacy of design.
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Contrary to the above, prior to November 20,1997, the licensee failed to correctly translate the manufacturer's recommendations for RHR motor starting 3
limits into operating instructions considering the expected RHR motor ambient l
temperature. Specifically, the limit for consecutive pump starts (three in five l
minutes) specified in the RHR operating procedure was based on a maximum ambient room temperature of 86*F. However, the maximum normal operating
(
temperature for the RHR corner room is 109 F and the room temperature may l
reach as high as 155*F during accidents. (02014)
This is a Severity Level IV violation.
(1)
Admission or Denial of the Alleaed Violation l
l Vermont Yankee does not contest this violation -
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'(2)~
Reasons for the Violation I
l The reason for this violation was a weakness in our configuration control process in that i
we did not translate the most limiting requirements for RHR pump ressrts into our operating and surveillance procedures.
(3)
' Corrective Steos Taken and the Results Achieved After consultation with the motor manufacturer, we have modified our operating and surveillance procedures for these pumps to correspond to the most limiting pump start conditions.
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VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98 73 / Page 8 14)
Corrective Steos That Will be Taken to Avoid Further V'olations As discussed in the response to 1.A above, Vermont Yankee initiated a Configuration Management improvement Project (CMIP) in February 1997. The objective of the CMIP is to enhance and streamline the configuration management processes at the Vermont Yankee Nuclear Power Station (VYNPS) to establish, f acilitate the use of, and maintain design basis documentation. Several projects have been initiated which will allow for the capture, maintenance, retrieval, and update of design basis information, and the eventual integration of design bases information to allow for accessibility across the organization. These projects, though varied in scope, will establish an integrated VYNPS configuration management plan, and willidentify and bring to resolution similar events in the future.
The CMIP includes:
Design Basis Documents (DBDs) development, Validation of DBDs versua Plant, e
Process improvements in which integrated / streamlined procedures that include the e
integration of the DBDs, improved Technical Specification Program, engineering program documents, and engineering and licensing information into the CM process will be developed and implemented, and
'e F3AR Verification.
The generalintent of the DBD Program is to provide a centrallocation for design basis information with emphasis on design intent or basis. The DBDs are intended to provide a sufficient level of information to support current plant operation, future modifications, or quick response to operating events. The DBDs link all of the design and licensing 4
basis requirements for the specific systems being addressed.
)
The validation process encompasses a review of the design basis requirements identified in the DBDs as well as an SSFl type review of each system to provide reasonable confidence that the system will provide its intended function.
The process improvement element of the project encompasses the development and implementation of integrated and streamlined procedures that include the integration of DBDs, improved Technical Specification Program, engineering program documents, and engineering and licensing information into the configuration management process. The efforts are focusing on the major engineering processes which include drawing control, modification or change control, safet/ evaluations and calculations.
The purpose for performing FSAR verification is to verify that the FSAR accurately reflects the plant configuration and associated design bases. This will be accomplished by identifying any FSAR statements that are incorrect or for which a documented bacis is not available and one is warrantea, and taking the appropriate corrective actions.
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'(5)
Date When Full Comoliance Will be Achieved Full compliance was achieved on August 26, 1997 when the applicable revised operating and surveillance procedures were issued.
2.
Contrary to the above, prior to May 9,1997, the licensee failed to correctly I
select equipment in a subsystem essential to the safety-related function of the emergency diesel generators (EDGs). Specifically, air to the solenoid valves that operated the EDG service water cooling flow control valves (FCVs) was supplied from a nonsafety-related pressure regulator. Failure of the pressure regulator could have resulted in a malfunction of the solenoid valve which could have prevented the FCVs from opening. The failure of the flow control valve could cause a loss of all service water to the EDG which would prevent operation of the EDG. (03014)
This is a Severity Level IV violation.
(1)
Admission or Denial of the Alleaed Violation i
I Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation The cause of this violation was that Piping and Instrumentation drawings and the maintenance database used to determine component / safety classification were inadequate in that they did not identify these regulators and consequently were not appropriately categorized as safety-related.
(3)
Corrective Steos Taken and the Results Achieved Safety classification worksheets were initiated to verify the safety classification for each of the air regulators. Drawings were revised to show the correct type and model i
of SOV. In addition, individual air regulators were added to the drawings. The MPAC database was also revised to include the air regulators as subcomponents of the air i
controller.
A review for similar conditions was performed and two other air regu!ators were found to be similar and a separate ER initiated. These regulators were appropriately isolated and the procedures changed, thus completing the required actions for this item.
(4)
Corrective Stoos That Will be Taken to Avoid Further Violations As discussed in ll.A.14 above, the CMIP Program will address a number of design basis and configuration controlissues. Those aspects of the program that apply specifically I
to the issue identified in this violation include validation and process improvements. The validation effort will continue to review for similar events and identify and correct them f
VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98 73 / Paga.10
' when discovered. : Validation team orientation and training focuses the validation effort -
to look for similar issues to those raised during the AE Inspection as well as significant issues identified in previous validations on a system by system basis. The changes being i
made to the drawing process will include identifying expectations relative to the type and extent of information that will be shown on a P&lD. This should ensure consistency in the information'added to the drawings in the future.
(5)
Date When Full Comoliance Will be Achieved Full compliance was achieved on 5/23/97 when all four air regulators (two for each EDG service water valve) were replaced with qualified components.
3.
Contrary to the above, prior to November 20,1997,' the licensee failed to correctly translate RHR flow specifications into procedures. Specifically, the
- flow limitations specified in RHR operating procedure for minimum pump flow requirements did not consider instrument uncertainty in the specified limit. The RHR procedure included a minimum flow precaution of 2700 gpm. However, considering uncertainty of the flow instrument, an indicated flow rate of 3920 gpm was required to ensure that the vendor recommended minimum flow of 2700 gpm was established. - (04014)
This is a Severity Level IV violation.
(1)
Admission or Denial of the Alleoed Violation i
Vermont Yankee does not contest this violation.
.(2)
Reasons for the Violation Instrument uncertainty was not consistently addressed during original plant design.
-(3)
Corrective Steos Taken and the Results Achieved Following identification of this issue, operating and surveillance procedures were revised and training was provided to operators on this issue. The procedure revisions and training combined to emphasize tne following:
A detailed description of the concern e
Emphasis was placed on minimizing pump operation in minimum flow conditions e
Securing pumps when not required e-l insfrument uncertainties e
Our review of other plant systems pertaining to this issue identified that the Core Spray system instrumentation also had an issue resulting from instrumentation uncertainty.
. The same. corrective actions were implemented for both the RHR and Core Spray systems.
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VERMONT YANKEE NUCLEAR POWER CORPORATION
' BVY 98-73 / Page 11 14)
' Corrective Steos That Will be Taken to Avoid Further Violations The RHR and CS flow instrumentation design is being upgraded during our current outage. Procedure changes will be implemented prior to startup that reflect the updated minimum flow requirements based upon vendor input and the new instrumentation installed, with instrument uncertainties taken into consideration.
Vermont Yankee is engaged in a' comprehensive instrument setpoint program. The program will address normal, accident and surveillance uncertainty in the monitored parameters. This is expected to be complete by December 31,1999.
The. validation of DBDs versus the plant element of the CMIP has found and will continue to investigate similar issues in other systems.
(5)
Date When Full Comoliance Will be Achieved Vermont Yankee will achieve full compliance prior to startup from our current refueling outage with the installation of new RHR flow instrumentation and corresponding procedure changes.
4.
Contrary to the above, on December 6,1995, the licensee used incorrect design inputs in the calculation of NPSH margin for the RHR pumps in calculation VYC-808, Rev. 2.
Specifically, the licensee used a curve fit of the vendor's pump test data in calculating the required NPSH values rather than actual test data.
Use of the curve fit data resulted in a nonconservative NPSH required value.
(05014)
This is a Severity Level IV violation.
(1)
Admission or_ Denial of the Alleoed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation The reason for this violation was a personnel error in a calculation such that there was an error in developing a curve fit equation from the vendors plotted pump test curve (vs.
tabulated data) which resulted in a reduction of the minimum required NPSH of about 0.5 ft for these pumps.
(3)
Corrective Steos Taken and the Results Achieved As an immediate action, an assessment was performed which identified that there was sufficient conservatism in the calculation to offset the curve-fit error; documentation was included in the calculation file.
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VERMONT. YANKEE NUCLEAR POWER CORPORATION
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BVY 98-73 / Page 12.
l The NPSH calculation was revised (VYC-808, Rev.3) on January 13,1998 to correct l-this error.
Training, via meetings with the engineering organization, was provided to design engineering personnel on this issue einphasizing the need for attention to detail and l.
verifying the validity of calculation inputs.
l (4)
,Qorrective Steos That Will be Taken to Avoid Further Violations The validation of DBDs versus the plant element of the CMIP includes a review of critical l-system calculations for the important safety systems and initiates additional corrective actions as necessary.
l lt should be noted that a calculation revision is being processed to coincide with the installation of our new ECCS suction strainers for RHR and CS systems. These new suction strainers are being installed during our current refueling outage
.(5)
Date When Full Comoliance Will be Achieved Full compliance was achieved on January 13,1998 when calculation VYC-808 was
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revised.
5.
Contrary to the above, prior to November 20,1997, the licensee failed to update l
the heat exchanger fouling assumption used in RHR service water (RHRSW) room cooler thermal performance calculations after an inspection of cooler unit coils in April 1995 indicated that the assumption was incorrect.
Specifically, Calculation VYC-1329 was not changed to reflect micro-fouling as the likely cause of the fouling, rather than tube plugging due to silt, after no evidence of silt fouling was found during the inspection. (06014)
This is a Severity Level IV violation.
(1)
Admission or Denial of the Alleoed Violation Vermont Yankee does not contest this violation.
-(2)
. Reasons for the Violation This event resulted from a weakness in our configuration control process, since the assumption in the calculation was not updated following the coil inspection. Note that although the field condition did not match the analyzed condition, at that time the.
calculation was reviewed and it was concluded that the original results were conservative and bounded the results for the as found configuration.
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VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98-73 / Page 13
'(3)
Corrective Steps Taken and the Results Achieved Engineering management has reinforced expectations to maintain the calculations such that they reflect actual plant conditions.
Vermont Yankee developed a new thermal performance test method that eliminated the need for calculation VYC-1329. VYC-1340-A Rev.1, RRU-7/8 Thermal Performance Acceptance Criteria, was approved on March 11,1998 and acceptable tests were performed on both coolers using the revised methodology by March 20,1998.
(4)
Corrective Steos That Will be Taken to Avoid Further Violations As discussed in ll.A.1.4 above, the process improvement element of the CMIP will incorporate those changes necessary to strengthen both the design change and calculation processes in the areas identified. In addition, the System Engineering Department now ensures that these types of issues remain valid relative to assumptions in calculations.
(5)
Date When Full Comoliance Will be Achieved Full compliance was achieved on March 20, 1998 when acceptable tests were completed for both coolers using a revised methodology that did not rely on VYC-1329.
(6)
Engineering Instruction WE-103, " Engineering Calculations and Analyses," Rev.
15, dated October 14,1994, section 4.1.4.2, stated that, when information from quality assurance (QA) design records was required, the licensee must ensure that the appropriate (governing) documents were used and that such documents were the latest approved revision obtained from the appropriate source.
Contrary to the above, in April 1997, the licensee failed to assure correct references and inputs were used in design calculations. Specifically:
Calculation VYC-1349, Rev.1, dated April 30, 1997, referenced drawing G-191372, Rev. 41; however, engineering had approved Rev.
42 of the drawing G-191372 on December 20,1996.
Calculation VYC-298, Rev.10, dated April 22, 1997, referenced various drawings as listed in Section 3.0.5 (a) through (I), which were superseded by a later revision before the licensee issued Calculation VYC-298, Rev.10. The latest revisions of the drawings indicated j
some de load changes. (07014)
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This is a Severity Level IV violation, j
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BVY 98 73 / Page 14
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(1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation l
The reason for this violation was a failure to follow procedures.
(3)
Corrective Steos Taken and the Results Achieved 1
An evaluation was performed on 8/11/97 and no technical issues with calculation i
VYC-1349 Rev.1 were identified. This calculation is currently being revised and is the I
final review process.
Calculation VYC-298 was revised on 3/18/98.
Engineering has reinforced procedure compliance expectations, through presentations to the engineering organization, that when revising calculations, all references must be verified current or appropriate actions taken to evaluate and include updated references.
(4)
Corrective Steps That Will be Taken to Avoid Further Violations Calculation VYC-1349 is currently being revised. This revision is expected to be complete by May 18,1998.
As discussed in ll.A.1.4 above, the process improvement element of the CMIP will include revisions to our drawing and calculation control processes based upon these and 1
other similar issues.
In addition to the corrective actions the DBD generation and validation elements of the CMIP is also evaluating the adequacy and accuracy of the critical system calculations and drawings and initiating corrective actions where concerns are identified.
(5)
Date When Full Comoliance Will be Achieved Full compliance will be achieved when calculation VYC-1349 is revised. This is currently expected to be complete by May 18,1998.
j B.
10 CFR Part 50 Appendix B, Criterion XVI, Corrective Action, requires, in part, that measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected. in the case of significant conditions adverse to quality, the measures shall assure that the cause of the condition is determined and corrective action taken to preclude repetition. The identification of the significant condition adverse to quality, the cause of the condition, and the
VERMONT YANKEE NUCLEAR POWER CORPORATION 4
BVY 98-73 / Page 15
' corrective action taken shall be documented and reported to appropriate levels of management.
1.
Contrary to the above, between November 13, 1986, and May 1997, the licensee failed to properly evaluate and correct the nonconformance between the vendor recommended RHR pump minimum flow requirement of 2700 gpm and the installed minimum flow capacity of 350 gpm. Specifically, in a letter dated November 13,1986, the vendor notified the licensee that the minimum flow for the RHR pumps should be increased to 2700 gpm for continuous operation (more than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> of operation in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) and to 2075 gpm for intermittent operation.
However, the licensee failed.to adequately correct this nonconformance, despite prior opportunities, namely:
The licensee's response, dated May 8,1989, to IE Bulletin 88-04, which requested licensees to determine (and correct) whether the installed minimum flow capacity was adequate for pump operation, lacked the technical basis to conclude ^. hat the existing RHR pump minimum flow would be adequate during postulated accident scenarios during which the i
pump would operate for several hours under minimum flow conditions.
The licensee's response did not provide either verification from the 1
vendor or test results to demonstrate that minimum flow rates were adequate during the postulated accident scenarios. The vendor was unable to support the licensee's assertion that a cumulative arithmetic j
series of minimum flow events over the life of the plant (29,200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br />) had the same relationship to pump degradation as the length of a specific event (4 to 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> of minimum flow operation during an accident).-
The licensee added a precaution to the RHR operating and surveillance procedures, in 1987, to minimize operation of the RHR pumps in the minimum flow mode. These instructions did not adequately reflect the vendor recommendations, provided in November 1986, to increase the minimum flow to 2700 gpm. Although, the RHR operating procedure was revised in May 1997, and additional instructions were provided to reflect the vendor recommendations, these instructions did not reflect the recommendation, provided in May 1997, that RHR pump operation should not be sustained at a flow rate of 350 gpm for rrore than 30 seconds during surveillance tests. (08014) l This is a Severity Level IV violation.
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(1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation, t
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'.-VERMONT YAt0KEE NUCLEAR POWER CORPORATION I
I BVY 98-73 / Page 16
.k2)
Reasons for the Violation
- The Vermont Yankee personnel involved failed to understand and correctly implement the vendors pump minimum flow requirements using engineering interpretation of the L
vendors data, a GE evaluation, and the results of visual examination of the VY pump.
' impellers to correlate previous service time at the reduced minimum flows.
(3)
Corrective Steos Taken and the Results Achieved Following' identification of this issue, additional manufacturer and engineering input was sought. During this period operating and surveillance procedures were revised and I
training was provided to all operators on this issue. The procedure revisions and training r
combined to emphasize the following:
A' detailed description of the concern Minimizing pump operation in minimum flow conditions e
Securing pumps when not required e
Instrument uncertainties
'e These same controls were implemented for both RHR and CS systems.
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- Tests were performed on an RHR and' CS pump to measure pump vibration and
. performance at the originally specified minimum flow values. The pumps operated L satisf actorily with ' acceptable vibration levels at these flows. This information was transmitted to the pump vendor who provided us with unambiguous minimum flow
. requirements which indicate that the RHR pumps can operate for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> at the original minimum flow of 350 gpm. RHR minimum flow operation beyond 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> requires a flow of 2700 gpm.
L (4)
Corrective Steos That Will be Taken to Avoid Further Violations The pump flow instrumentation is being upgraded as part of our current refueling outage j
i to assure pump operation within the envelope currently endorsed by the pump vendor, Procedural changes are being made to ensure that the required pump minimum flow values (with vendor concurrence), including instrument uncertainty are implemented.
This type of issue has been and 'will continue to be discovered as part of the DBD preparation and validation, elements of the CMIP.
- (5)
Date When Full Compliance Will be Achieved Full compliance will be achieved by startup from our current refueling outage when our procedures are revised to incorporate the final vendor guidance and including the new instrumentation.
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VERMONT YANKEE NUCLEAR POWER' CORPORATION BVY 98-73 / Page 17 2.
Administrative Procedure (AP) 0009, " Event Reports," a measure established by the licensee to implement the requirements of 10 CFR Part 50, Appendix B, Criterion XVI, requires, in part, that event reports be initiated for unanalyzed conditions or potential conditions outside the design basis, and that the event be reviewed against the requirements of the Basis for Maintaining Operation (BMO) Guideline to determine if a BMO is required.
The BMO Guideline states, in part, that if a safety-related component or system is degraded relative to the Final Safety Analysis Report (FSAR) or other licensing commitment, then a BMO should be prepared.
Contrary to the above, prior to November 20,1997, the licensee failed to take appropriate measures to assure that a condition adverse to quality involving the service water (SW) and emergency diesel generator (EDG) support systems was appropriately evaluated and corrected. Specifically, the S'N supply line to the circulating water and SW traveling screens, SW piping to the diesel generators outside the diesel generator rooms in the turbine building, fuel oil transfer lines routed on the exterior of the pump house, and the diesel exhausts,'were not adequately protected from the effects'of tornadoes, including tornado missile strikes. This constituted a degraded condition relative to commitments in the Preliminar*/ Design Assessment Report (PDAR); however, no BMO was prepared.
(09014)
This is a Severity Level IV violation.
(1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation The reason for this violation was the initial assessment that protection of external piping
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was not a licensing basis requirement. This issue was recognized as a generic issue for
.VY vintage plants that was to be dispositioned as part of our IPEEE evaluation and submittal. Based upon this, no BMO was written.
(3)-
Corrective Steps Taken and the iesults Achieved r
The Event Report for this issue was re-screened to require a BMO, and BMO 97-44 was approved and issued on 11/3/97. Corrective actions from this BMO, which include procedure changes, analytical solutions, development of an external events DBD and l
preparation of VY's IPEEE report are all currently underway.
BMO training was given to department managers on the expectations and requirements of the BMO process and Generic Letter 91-18.
1 Vermont Yankee has lowered the threshold for initiating the BMO process.
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VERMONT YANKEE NUCLEAR POWER CORPORATION l
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BVY 98-73 / Page 18 (4)
' Corrective Steos That Will be Taken to Avoid Further Violations
'We will continue to monitor the BMO process through self-assessments and audits.
An External Events Topical Design Basis Document is being prepared to capture those external events that are within Vermont Yankees licensing and design basis..This will address events such as tornadoes, flooding, hurricanes, etc.
'(5)
Date When Full Compliance Will be Achieved Full compliance was achieved on 11/3/97 when BMO 97-44 was approved.
C.
10 CFR 50.73(a)(2) requires, in part, that licensees shall submit a Ucensee Event Report (LER) within 30 days after the discovery of the event, for any event or condition that alone could have prevented the fulfillment of the safety function of systems that are needed to remove residual heat.
L Contrary to the above, between June 6 and November 20,1997, the licensee failed to report a condition that alone could have prevented the fulfillment of the safety function of the RHR system, a system needed to remove residual heat. Specifically, on June 6, 1997,' the NRC identified - that instrument uncertainty was not included in the specification of RHR pump minimum flow requirements in system procedures and as of November 20,1997, the licensee had not submitted a LER, a period in excess of 30 days. 'The failure to provide adequate instructions for RHR pump minimum flow requirements could have resulted in failure of the RHR pumps which would have prevented the fulfillment of a safety function of a system required to remove residual heat. (10014)
This is a Severity Level IV violation.
(1)
Admission or Denial of the Alleaed Violation Vermont Yankee does not contest this violation.
(2)
Reasons for the Violation i
i The Vermont Yankee deportability procedure lacked guidance for conservative application of the term "retsonable expectation".
l NUREG 1022, Section 3.3.3 states:
"The level of judgement for reporting an event or condition under this criterion is a reasonable expectation of preventing fulfillment of a safety function" I
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VERMONT. YANKEE NUCLEAR POWER CORPORATION BVY.'98-73 / Page 19 l
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(3).
' Corrective Steos Taken and the Results Achieved j
Vermont Yankee submitted LER 98-02 for this issue on February 27,1998.
q Our procedure governing deportability has been revised to include interim guidance -
relating to the application of the term " reasonable expectation".
(4) forrective Steos That Will be Taken to Avoid Further Violations Vermont Yankee has initiated a benchmarking effort'to improve our reporting process.
This effort includes' interviews with Licensing and regulatory Compliance personnel l
representing numerous BWR plants of comparable vintage.' To date, licensing personnel representing 8 operating units have been interviewed.to determine the processes, thresholds, and industry guidance considered appropriate when evaluating conditions for deportability requirements subject to 10CFR50.73. The benchmarking survey is expected to be completed by June,1998. The survey results will be assessed in light of BWR Owners Group initiatives and rulemaking efforts by the Commission. The-l lessons learned from from these activities will be factored into our deportability process.
I l-(5)'
~ Date When Full Comoliance Will be Achieved l'
t-l Full compliance was achieved on February 27,1998 when LER 98-02 was submitted.
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VERMONT YANKEE NUCLEAR POWER CORPORATION BVY 98-73 / Page 20 As instructe'd in the Notice of Violation enclosed with Reference (a), an electronic transfer in the amount of $55,000 was completed on May 14,1998.
We trust that the information provided is acceptable. However, should you have any questions or desire any additionalinformation, please contact this office.
Sincerely, VERMONT YANKEE NUCLEAR POWER CORPORATION
/
(
Don M. Leach Vice President, Engineering
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4 > O'U!O&
Vg 4
s STATE OF V ERMONT
)
NOTAR's 1
)ss WINDHAM COUNTY
)
d FUBUC A
h Then personally appeared before me, Don M. Leach, who, being duly sworn, gtate that Vice President, Engineering of Vermont Yankee Nuclear Power Corporation, 100Uti authorized to execute and file the foregoing document in the name and on tDi.1...
f Vermont Nuclear Power Corporation, and that the statements therein are true to the best of his knowledge and belief.
>L h Ja {
5'alfy A/ Sands'trum, N'otary Public My Commission Expires February 10,1999 cc USNRC Region 1 Administrator USNRC Project Manager - VYNPS USNRC Resident inspector - VYNPS Vermont Department of Public Service I
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